A survey of respiratory disease among New York City postal and transit workers

ESVIROSMEiYTAL

1, 265-286

RESEARCH

A Survey

(1967)

of Respiratory City

Postal

and

I. Prevalence PAUL The

New

nl.

DES~EN,

I’ork

City Health n.f h’ew York

ELLEN

W.

,JOXES,

Disease

Among

Transit

Workers

New

York

of Symptoms’ HWAN

E. BASS,

ANI,

JOHEPH

Department and the Afeclical and Health Research City, Inc., 125 Worth Slrer,t. New York, N.Y. 10013 Rrceilvd

SPptenaber

I~RIXXH Association

90, 10%

The New York City Health Departmc~nt has conducted a survey of respiratory symptoms among postal and transit workers as a part of ongoing epidemiologic studies of chronic respiratory disease. This report, the first of a series on the survey findings, presents the study design together with data on prevalence of symptoms. A total of 12,604 men were interviewed, using the British Medical Research Council’s questionnaire, and were tested with the McKesson Vitalor. The study covered all men in specified job categories and included white and non-white men ranging in age from 20 to 70. The prevalence of chronic bronchitis was found to be 15% for white and 10% for non-white postal workers, compared with rates of 12 and 9%, respectively, among transit workers. Respiratory disease symptom prevalence rates are reported according to age, race, smoking habits, job classification, and area of residence. A g ,suhgroups identified by the prevalence follow-up of 2,000 transit workers representin survey is now in progress.

In this survey of respiratory disease symptoms among New York City postal and transit workers 12-15% of the white men and g-10% of the non-white men were found to have chronic bronchitis as defined by the American Thoracic Society, (“persistent cough on most days for 3 months of the year for at least 2 years”) (American Thoracic Society, 1962). These figures take on added significance when viewed against the background of increasing mortality from chronic bronchitis and emphysema. In 1950, the New York City death rate from these causes combined was about 10 per l,OOO,OOO population; by 1965, the rate had increased sevenfold. During this same period the United States as a wholr also experienced a marked increase in mortality from these two causes. If the upward trend of these mortalit,y rates is to be altered, knowledge of the nature and extent of the problem in the population, and identification and follow-up of individuals at risk of developing obstructive lung disease is essential. The New York City Health Department is engaged in a long-term study of the respiratory disease problem. Because of the paucity of morbidity data on chronic respirat.ory diseases the init.ial problem was to obtain a measure of the preralence of respiratory disease symptoms in the population. Two working populations, postal and transit workers, were sclectcd for study, and during the period 1961-1963 a survey of respiratory discasc symptoms was conducted among ’ This

study

was made

possible

by USPHS

grant 262

OH-00013.

RESPIRATOR\-

DISEASE

IN

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CITY

263

these men. The findings of the survey provided data confirming the existence of a respiratory disease problem in the population and also delineated certain highrisk groups. They also pointed to the need for a more precise definition of characteristics of high-risk groups, not only from the standpoint of risk of developing the disease, but also from the standpoint of risk of progressive deterioration. It n-as with t,his object in view that the second or follow-up part of the investigation was launched in 1964. Work continuea on the follow-up of some 2,000 men selected for study on the basis of significant, charact’eristics revealed in the initial survey. The present report is the first of a series projected for these studies. It dcscribcs in detail the methods and procedures of the initial survey, from which the followup study has been developed, and presents the basic survey findings wit.h regard to the prevalence of symptoms. Subsequent reports from the survey will offer clutn on vcntilatory function tests and prerwlcnce of symptoms, a detailed examamong transit ination of apparent race differences, and n study of absrntccism workers related to the survey findings of symptoms of respiratory disease. The specified aims of the New York City survey of postal and transit workers Tvcre to determine the prevalence of symptoms of chronic respiratory disease :mong two defined industrial groups and to relate these findings and the results of pulmonary function tests to specific occupatiou, place of residence, age, race, :md other environmental or demographic factors. A unique feature of this survey i:: its size. Over 12,600 adult males were interviewed, covering a somewhat wider :~gc range than other studies ancl including white and non-white men. An ndvautage of starting with large numbers is particularly evident when an attempt is made to isolate the effect of smoking on respiratory disease symptoms because o\-cn in large population samples the numbers of non-smokers available for study :\rc’ relatively small. The large number;; in this initial survey also provided a Inroad base for selection of men on whom the concrentratc~rl efforts of follow-up c~)uld be expected to be most productive. METHODS

.iND

PROCEDURES

Postal workers included in the study were defined as all letter carriers, including ~pccial delivery carriers, collectors and parcel postmen, and all full-time mail truck drivers working out of postal stations in the boroughs of Manhattan and the the Bronx. Since the rate of personnel turnover in these Post Office stations was reportedly high, particularly in the lower grades of the Civil Service system, and since the survey was carried out on different dates in the 57 stations covered, the study population was further defined as including those men in the specified occupational categories who were currently employed on the survey dates in the respective stations. The total number thus defined was 6,077, of whom 5,381 were carriers and 696 were full-time truck drivers. Transit workers included in the survey were all employees of the Xew York City Transit Authority in the payroll titles of Motorman, Surface Line Operator, or Surface Line Dispatcher on February 10, 1962. These men numbered 8,440, of whom 3,135 were motormen. 4,822 were surface line operators and 483 were dispatchers. Records of illness absenteeism of three work days or longcr for all transit

264

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BREUER

workers in the defined population provided additional information on occurrence of respiratory diseases in this survey group, and a means of evaluating surf?: findings for t’he group. Instruments of the New York City survey were an adaptation of the British lledical Research Council’s questionnaire (Appendix A) and the McKesson Vitalor (McKerrow, 1961). Choice of these instruments for determining prevalcncc of respiratory symptoms and measuring pulmonary ventilatory function was dictated by the desire to obtain data which, insofar as possible, would be comparable with data obtained in field surveys in Great Britain, To this end, the British recommendations for training and supervising interviewers by means of tape-recorded interviews which could then be monitored for errors or inconsistencies were followed scrupulously’. All of t,he interviews obtained in the Post Office stations were taped, monitorecl, and corrected where necessary. The first, 2,000 interviews of transit workers were taped and handled similarly; subsequently, interviewer technique was re-evaluated through taping spot samples of intervielvs. A total of 12 interviewers, in addition to the authors and two guest trainees, conducted the interviews throughout the 2 years of field work on the survey. Three of thcsc worked in the Post Office phase exclusively, and one worked only in the early months of the survey among transit workers; the remaining eight interviewers worked with both study groups, and four of t,hese interviewed large numbers of both postmen and transit workers. The measurement of pulmonary function obtained with the 3IcKesson Vital01 was the l-second forced expiratory volume (FET’,.,), defined as the volume of air which, after maximum inspiration, is forcibly expired in 1 second. For each study participant, an attempt was made to get two ‘Lsuccessful” tests after one practice attempt. The result recorded for study purposes was the maximum volume obtained, regardless of sequence of attempts. Other details of the preliminary organization of the survey have been described in a previous report (Densen et al., 1962). To summarize the logistical arrangemen& : the Post Office survey was conducted in each of 55 postal stations and the t,wo garages in Manhattan and the Bronx; transit worker interviews and tests were carried out. in space allotted by the Transit Authority Medical Department in each of its three medical clinics. All of the survey interviews were done during the participants’ official duty hours. Postmen were interviewed usually at the beginning of their working day or when they returned from their routes. Transit workers were seen at the time they reported to Transit Authority medical clinics for compulsory periodic medical examinations. Since all transit workers in the occupat’ional categories with which t,he survey was concerned are required to have annual examinations if 50 years of age or over, or biennial examinations if under 50, this meant that the entire transit populat’ion would bc expected to pass through the clinics in a a-year period. Of prime importance among activities preliminary to initiation of the study procedures, was that of securing the approval and cooperation of the employers concerned-the Postmaster General’s Office, Regional and New York City offices 2For the initial intensive Department staff were most srhool, Department of Social

training fortunate Medicine,

in the use of the British questionnaire the Health in having Dr. Walter Holland of St. Thomas’ Mrdical London, England, as a mentor.

RESPIRATORY

DISEASE

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CITT

of the Post Office Department, and the New York City Transit Aut’hority, and tllc lahor unions of which the study participants are members--the New York Local of the Kational AssociaGon of Lc$ter Carriers, Local 100, Transport Workers Union, AFL-CIO, and the Amalgamated Association of Street Electric Railway and ;1Iotor Coach Employees of America. Without the approval and actire cooperation of these organizations there could have hccn no surety. In presenting the prevalence survey to both cinploycr and member union groupq the confidentiality of the information was cmphasizecl, as was the fact, that participation was on a voluntary basin. Efforts to enlist the cooperation of the indiriduals selected for study included, in addition to the moral suasion of the employer-organization, distribution of informational leaflets, both to individuals and for posting in work places and locker rooms. Survey procedure:: were begun in the Transit .duthority clinics in Kovcmbcl 1961 and concluded in August 1963. Post Office interviews wcrc begun on May 1, 1962 and completed in November 1962. The numbers of men interviewed in these t.wo groups are shown in Table 1. Attention is called to the 427 “additional”

NUXIRERS

TABLE I OF POSTAL AND TRANSIT WORKERS OF CHRONIC RESPIRATORY DISEASE, NOVEMBER 1961-AmusT

Total in survey groups Interviewed Not interviewed Additional interviews” Total number interviewed

SURVEYED FOR PREVALENW NEW YORK CITY 1963

Postal workers

Transit workers

6,077

8,440 6,864 1,576 427

5,313 764

5,313

7,291

a Post office: Total defined as carriers and chauffeurs on the employment rosters of the respective stations and available for study on the survey dates in the respective stations, including men off sick or refusing interview, and those missed for other reasons; excludes men on annual or compensatory leave or on temporary assignment elsewhere. Transit: Total defined as all in payroll t,itles of Motorman, Surface Lines Operator and Surface Lines Dispatcher as of February 10, 196’2. h Number (in transit group) represents men in specified occupational categories at time trf interview but who were newly employed (or acquired the title) after February 10, 1962.

interviews among the transit workers. These represent men who were either newly employed or acquired the specified payroll titles after the study definition date of February 10, 1962. They were interviewed along with their senior COworkers as they appeared at the Transit Authority clinics for their scheduled medical examinations in the period from February 10, 1962 through August 1963, when the survey was terminated. As would be expected, this newest cohort among the transit workers differed from workers of longer tenure in certain basic population characteristics. However, it was found that among this relatively small group of men, differences, particularly in reference to symptom prevalence rates, were not of an order to have a marked effect on the rat,es for the total group and information on these men has been included in t,he data presented for “interviewed” transit workers.

266

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RESULTS

Percentage

of Populations

Interviewed

The percentages of men reached by survey procedures in each of the specified work groups are shown in Table II. The overall percentage of defined postal population interviewed was 87.4. A higher percentage of carriers were included (88.7%) than of drivers (77.6%). Outright refusals were rarely encountered in either major study group; they RWC recorded in fetter than lo/O of the Post Office SUNBER

AND PERCENTACE

TABLE II OF POSTAL AND TRANSIT BY AGE AND BY OCCUPATION Postal

WORKERS

INTERVIEWED,

workers

Transit

Interviewed

Age in years and occupation All ages, all rategories

workers Interviewed

s nmh available fol survey

Xumber available for survey

Sumber

Number

6,077

.i,313

s,440

6,864”

s1 3

2,601 2,275 1,03s 146

2,271 2,02i 895 120

Si.3

3,050

89.1 86.2 82.2

3,163 2,532 665 10

1,674 2,546 2,169 475 -

80.9 80.5 il.4 -

4,ii3

88.i ii.6 -

4,145 357 2,382

S6.0 73.9 75.3

Percent ages of available s7.4

Percentage of available

Age Under 40 40-49 5&59 60 and ovel Unknown Occupation Letter carriers Drivers Surface line operalors Dispatchers Motormen

17 5,381 696 -

540

-

-

4,832 483 3,135

85.i

p Includes 3 men with incomplete histories; they are excluded from detailed tables following. b Includes 5 men with incomplete histories; they are excluded from detailed tables following, Does not include 427 interviews of men newly employed in specified categories after February 10, 1962.

population. To what extent unwillingness actually accounted for the deficit of 11.3% of carriers and 22.4% of drivers is unknown. It is believed that shortterm absenteeism plus lack of complete synchronization of survey work hours with postal work shifts were the principal reasons for lossesto the survey. Although survey work hours were for the most part tailored to fit the Post Office carrier schedules (beginning about 7 AM) it was impossible to staff throughout the 24 hours the large Post Office garage, which housed 668 of the 696 drivers available for survey, and whose work shifts began every 15 minutes around the clock. The possible bias in findings about respiratory disease symptoms that results

RESPIRATORY

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267

from 111~11 &ent from work because of ilhlcaa could not be nsse~sd for the Post Office population because of lack of relevant information about men not interv&-cd. In the transit group, however, records of illness absenteeism will give information on this subject. of the total transit worker population :LS originally defined, 81.3c/, WJY: interviewed and tested in the survey. For bus drivers (Surface Line Operators), the ‘q similar to that achieved in the Post Office. Among perccntagr was 86.0, which 1, tiispatclicr~ and motormen, pcrccntagcs included were 73.9 and 75.3, rcepcctivcly. The reason for these differenrcs among occupational groups in the transit population is largely an administrative one. Since the 2-year cycle of periodic medical csxlninations in t.he Transit -4uthority hogan September 5, 1961, the PU~‘VQ’, which A:likd nearly 3 moiith~ lat(lr, misxtl men reporting for exnmiuntione on :l I)ic~nllial schedule during that Scptcmber to November 1961 period. It w:~s potisil)l
The numbers of men designated for study and the numbers and percents of t’hese participating are shown in Table III for the New York City groups and for other U.S. urban areas from which surveys have been reported.

268

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TABLE NUMBER

AKD

group

New York City: Post office New York City: Transit San Francisco: Telephone workers (a) Los Angeles: Telephone workers (a) Kearney, N.J.: Cable shop (6) East Coast: Telephone plant men (“)

Symptoms

E. B.4SS,

AKD

J.

BREUER

III

PERCEKTAGE PARTICIPATING IN IN OTHER UKITED ST.~TES

Survey

n Deane, 1965. * Gocke, personal c Holland. 1965.

H.

THE NEK YORK URB.4N SURVEYS

Total designated for study 6,077 s,440 264 Y87 452 678

CITY

GROUPS

A?*',)

Participating n’umber 5,313 6,864 202 306 418 625

Percentage 87.4 51.:: 76.3 83.4 92 .5 92.2

communication.

by Swvey

Group and Race

The New York City adaptation differed from the 1960 Revision of the British Medical Research Council’s questionnaire principally in the omission of questions about occurrence of cough and phlegm in the summer (MRC questionnaire items 2, 4, 7, and 9). Prevalence of cough and phlegm in this report, therefore, is specifically that reported for the “winter” months. hlthough this difference should not affect comparability (between geographic areas) of data on “winter” questions, 1, 3, 6, and 8, it could make some slight differeuce in comparabilit,y of data on questions 5 and 10 (when not linked with that on foregoing questions), since items 5 and 10, according to the standardized interview procedure, arc asked only after an affirmative reply is obtained to one or more of questions l-4 and 6-9. This should be borne in mind in studying results of surveys in different. areas. The perccnbages of Kcw York City’s postmen and transit workers, white and non-white, reporting specified symptoms arc shown in Table IV and percentages of those reporting various combinations of symptoms appear in Table V. Of primary interest here are comparisons between postal and transit groups and between white and non-white groups. Looking at the results for the two indust.ries, it is apparent that the percentages with symptoms arc of the same general order of magnitude for almost all the questionnaire items, although the percentages of postmen with specified symptoms are consistently higher, numerically, t.han comparable percentages for t,ransit workers. Most marked differences, proportionately, between the two groups are in the rcportcd prevalence of dyspnca (question 14), wheezing apart from colds (15bj and the effect of weather (17 and 17f). Data for white and non-white men in these two industrial populations show t,hc same pattern of differences bet.ween postal and transit, workers within each racial group t.hat was observed for the combined races. Comparison of white and non-white rates within each survey group shows that racial differences observed in one group are similar to those in the other, both as to direction and magnitude of difference. An interesting pattern of answers to questions on cough and phlegm emerges.

RESPIRATORY

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CITY

TABLE IV PREVALENCE OF RESPIRATORY SYXPTOJIS AMONG POSTAL AND TRANSIT WORKERS, PERCENTAGE OF ALL INTERVIEWS WITH POSITIVE RESPONSES TO QUESTIONNAIRE Postal

Symptoma Total

number

interviewedb

Cough, &43x (1) Cough, day/night (3) Persistent cough (5) Phlegm, AM (6) Phlegm, day/night (8) Persistent phlegm (10) Exacerbations (12b,c) Dyspnea 2f (14a) Dyspnea 3f (14b) Wheezing (15) JYheezing with colds (15a) IVheezing apart from colds (151,) Persistent wheezing (15~) R’enther affects chest (17) Weather causes dyspnea (lif) Kasal catarrh (18) Persistent nasal catarrh (20) Chest illnesses past 3 years (‘31) ,\sthma (22) 1I:ty fever (23) CLNumbers following sympt,oms b Three postal interviews and I~ccnnse of incomplete information.

BY RACE: ITEMS

Transit

Total

White

Nonwhite

Total

White

Nonwhite

6,510

4,107

1,203

7,286

6,355

1,951

18.6

20.0

2.5 3 19..5 26.4 28.3 23.1 11.4 28.7 2.4 26.5 21.1 12.9 4,s IO.7 5.1 31.5 15.2 17.6 3 5 9.6

24.7 20.9 27.1 28.0 24.4 11.7 30.7 2. i 26.3 20.1 13.9 4.9 11.3 5.5 32.5 19.i 17.5 3.1 9.3

13.7 27.4 14.8 24.1 29.6 18.6 10.6

16.2 20.5 16.9 21.5 23.3

IS.1 19,s 18.2 22.4 22.8

11.0 22.7 13.4 19.1 24.5

1X.4

19.6

16.7

8.1

7.8

9.0

21.9

18.:i

19.9

11.8

1 3 27.4 24.5 9.6 4.4 8.7 3.9 28.3 13.3 18.0 4.9 10.3

1.3 25.0 22.0 8.6 3 .8 7.0 2.8 24.6 13.5 15.8 2.7 7.3

1.5 23.7 20.3 9 3 4.1 7.6 3 .‘)24.7 13.8 15.9 2.3 5.3

0’7 28.4 26.6 65 3.0 5.1 t

are questionnaire item numbers. 5 t,ransit interviews were excluded

from

detailed

1.8

24.3 12.6 15.5 3.9 7.5

tabulations

Cough and production of phlegm first thing on arising (questions 1 and 6) were reported more frequently by white than by non-white men, but cough and/o! phlegm later in the day or at night (questions 3 and 8) were reported by about the same percentages in the two racial groups, with the numerical edge in the non-white. Affirmative answers to questions about, chronicity (5 and lo), at eitller or both times of day, were given more frequently, however, by the white men interviewed. The British Medical Research Council’s Commit.tee on the Aetiology of Chronic Bronchitis summarizes severity of cough and phlegm as elicited by the MRC questionnaire according to the following scheme (British Medical Research Council, 1960) : Cough (or phlegm) grade 0 = negative to question 5 (or Cough (or phlegm) grade (‘ough

1

= affirmative

(or phlegm) grade 2 = affirmative 5 (or 10)

10)

to 1 OT3 (6 or 8) and to 5 (or 10) to both 1 and 3 (6

and

8) a&

to

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TABLE PREVALENCE

H.

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J. BREUER

V

OF VARIOUS COMBINATIONS OF RESPIRATORY SYMPTOMS AMONG TRANSIT WORKERS, BY RACE: PERCENTAGE OF ALL INTERVIEWS WITH POSITIVE R.ESPONSES TO QUESTIONNAIRE ITEMS

POSTAL

.&SD

Transi tJ

Postal Total

White

Nonwhite

Total

White

white

Total number interviewedb

,5,510

.$,107

l$OS

7,.??86

5,555

1,951

Persistent cough and phlegm (5, 10) Exacerbations, dgspnea 3 + (12b, c, 14b) Persistent cough and phlegm, exacerbations (5, 10, 12b, c) Persistent cough and phlegm, dyspnea 2+ (5, 10, 14a) Persistent cough and phlegm, dyspnea 3+ (5, 10, 14b)

113.4 0 ,8

14.6 I .I)

9 .5 0.2

10.8 0 .4

11.6 I) 4

0 3

:; ‘).

4.1

3.4

2.7

2,s

2.; i

7.4

s 0

5 :3

4. 5

5.1

2 s

1.0

1 .o

0.8

0.6

0,s

0.2

2. 6

25

I.9

1.4

1 ..i

1 .o

0.5

0 .5

0.2

0.3

0 .3

0. 1

Phlegm, AM, exacerbations, dyspnea 2 $ (6, 12b, c, 14a)

3 n

3 6

2 4

1.8

2. 0

1.4

Persistent cough and phlegm, chest illnesses (5, 10, 21) Persistent cough and phlegm, dyspnea 3+, rhest. illne.qses, (5, 10, 14b, 21)

:;.9

4.0

3 ,5

3.1

:; .3

2. 4

0.6

0.6

0.5

0.3

‘I O..J

0 ,2

Symptom”

Persistent cough and phlegm, excerbations, dyspnea 2 + (5, 10, 12b, c, 14a) Per&tent coughand phlegm, exacerbations, dyspnea 3 + (5, 10, l%, c, 14b)

NOW

8.S

‘I Numbers following symptoms are questionnaire item numbers. * Three postal interviews and five transit interview8 were excluded from detailed tabulations because of incomplete data.

Data for New York City postmen arranged in this way, Table VI, show a widening difference between the races with increasing severity of the symptonparticularly in the case of chronic cough. Returning to other prevalence data in Table IV for white and non-white men in both postal and transit groups, it is seen that white rates exceed non-white for shortness of breath, both when all grades arc considered (question 14, grades 2 or more) and when more severe grades arc considered (grade 3, shortness of breath when walking with others on level ground, or worse) and for noticcablc effect of weather on chest symptoms (questions 17 and 17f). In the Post Office, the white rate also exceeds t,he non-white for nasal catarrh of any degree (18 and 20). On the other hand, non-white pates in bot,h industrial groups are slightly higher than white for wheezing (item 15)) wheezing with colds (15a) and asthma

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(22). To the question on wheezing apart from colds (15b), however, white men in both groups ,answered “yes” more frequently than did the non-white, and the prevalence of persistent or chronic wheezing (15~) was not greatly different fol the two races. The combinations of symptoms shown in Table V include combinations that have been variously considered indicative of “chronic bronchitis,” or “chronic bronchitis syndrome,” or other clinical entities. The first combination listed ((IUWTABLE VI NUMBER AND PERCENTAGE OF WHITE AND Nos-WHITE POSTAL WORKERS REPORTING COUGH AND PHLEGM IS DIFFERENT GRADES OF SEVERITY All postmen

FVhite

Non-white -__---.---

Symptom and grade of severitya

Number

Total number interviewed

Percentage

Number

Percentrage

Number

Percentage

5,310

100.0

4,107

100.0

1,203

100.0

Cough Grade Grade Grade

0 1 2

4,273 544 493

SO.5 10.2 9.3

3,248 446 413

i9.0 10.9 10.1

1,025 9s so

85.2 8.1 G i

Phlegm Grade Grade Grade

0 1 2

4,083 509 718

iG.9

3,104 412 591

75.6 10.0 14.4

979 97 127

SL.4 8.0 10.G

9.6 13.5

* Cough (or phlegm) grade 0 = negative affirmative to 1 OT 3 (6 OT 8) and to 5 (or 1 and 3 (6 and 8) and to 5 (or 10).

to question 5 (or 10). Cough 10). Cough (or phlegm) grade

(or phlegm) grade 1 = 2 = affirmat,ive to both

Cons 5 and 10) is that which, by definition of survey procedures, is very nearly synonymous with the American Thoracic Society’s definition of chronic bronchitis. As pointed out in t’he introductory statement, 12-15s of the white and g-10% of the non-white men in these employed populations have chronic bronchitis. Percentages for all combinations are slightly higher for white men than for nonwhite men, since the individual questions contributing most heavily to the combinations arc those for which white rates esrced non-white. Syntpto~~~~s

and

Smoking

Anderson and Ferris (1962) have pointed out the importance of current cigarette smoking in the production of symptoms of chronic respiratory disease and the necessity for adjusting for smoking habits when the effects of other irritants are to be examined. It follows that comparisons of symptom prevalence in different population groups must, be made within specific smoking-habit, categories of the groups or after suitable adjustments for this variable have been made. In this study a smoker is defined as one who reports current consumption of tobacco at the rate of 1 gm (or one cigarette) per day, and a non-smoker is one who ha?; never smoked tobacco at, this rate for as long as 1 year. T}lc s:mokille

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categories that could be defined with relative precision were: cigarettes only (about 50% of the men interviewed) ; cigar and/or pipes only (10%) ; and nonsmokers (15%). Men in the “mixed” category (8%) are less readily described because of differences in relative proportions of tobacco consumed in different ways. Ex-smokers (about 17%), who by definition must have abstained from smoking for at least 1 month, are another heterogeneous group, ranging from men who smoked very little many years ago to those who recently stopped after smoking heavily over a long period of time. TABLE VII PREVALENCE OF RESPIRATORY SYMPTOMS AMONG POSTAL AND TRAXSIT WORKERS IN THREE SPECIFIED SMOKING CATEGORIES: PERCENTAGE OF ALL INTERVIEWS WITIT POSITIVE RESPONSES T O QUESTIONNAIRE ITEMS Postal

Transit

Smokers of cigarettes

Smokers of pipes, cigars

Symptom”

onty

only

interviewed

2,687

628

90s

3,745

Cough, AM (1) Cough, day/night (3) Persistent cough (5) Phlegm, AM (6) Phlegm, day/night (8) Persistent phlegm (10) Persistent cough and phlegm (5, 10) Exacerbations (12b, c) Dyspnea 2 + (14a) Dyspnea 3 + (14b) Wheezing (15) Wheezing with colds (15a) Wheezing apart from colds (15b) Persistent wheezing (15~) Weather affects chest (17) Weather causes dyspnea (17f) Nasal catarrh (18) Persistent nasal catarrh (20) Chest illnesses past 3 years (21) Asthma (22) Hay fever (23)

26.4 33.7 27.0 33.3

9.4 16.7 12.4

6.9 11.6 7.0

15.5

15.8

34.9

22.8 17.4 7.3 8.9 24.8 2.1 22.0 17.2 10.5 2.5 10.4 4.9 28.2 15.4 16.9 3.5 10.5

16.8 13.1 4.0 8.7

23.4 26.5 23.5 27.7 27.8 23.7 15.2 9.1 21.9 1.4 31.3 27.6

Total

number

28.9

19.0 13.0 31.7 2.3 32.7 26.0 16.1 6.3 11.2 5.4 33.5 21.0 18.6 3.2 8.3

a Numbers following symptoms are questionnaire

Nonsmokers

19.8 1.8 14.2 12.0 6.4 1.7 8.7 4.0 27.4 13.7 15.1 4.0 12.1

Smokers of cigarett,es only

11.1 5.3 7.9 2.8 27.7 15.4 17.5 2.5 5.3

Smokers of pipes, cigars Nononly smokers

-

765

1,012

8.0

4.9 10.7 6.4 10.3 14.1 9.5 2.6 6 0 11.7 0.7 13.7 11.8 4.2 0.7 5.4 2.6 18.1 8.7 12.0 3.4 13.3

14.9 10.5 15.8 18.8 14.1 7.2 5.9 14.2 0.5

19.2 16.9 5.4 2.7 5.5 2.1 18.3 10.3 14.5 2.4 9.0

item numbers.

The prevalence of respiratory symptoms is shown in Table VII for the present smokers of cigarettes only, the present smokers of cigars and/or pipes only and t’he non-smokers among the postal and transit workers. The outstanding evidence here is the excessive prevalence of symptoms of cough, phlegm, shortness of breath, wheezing, and nasal catarrh among cigarette smokers as compared with non-smokers, and even as compared with cigar or pipe smokers. Cigarette smokers

RESPIRATORY

DISEASE

IN

XEW

YORIi

273

CITY

also report more frequently than others the occurrence of recent exacerbations of cough and phlegm and one or more chest illnesses requiring cessation of usual activities within the past 3 years. Only asthma and hay fever, among the listed single items, were reported with greater frequency by non-smokers than by smokers; there may be a selective factor here in that asthmatics and hay fcrcl victims may refrain from smoking because of the nature of their complaint. Symptoms

and Amount

Smoked

The significance of the different patterns of symptom prevalence with respect to smoking habits can be tested by analysis of prevalence of symptoms with respect to amount smoked. Tables VIII-XI show prevalence of selected sympt.oms among cigarette smokers and cigar or pipe smokers who reported using fewer than 15 gm of tobacco each day, 15-24 gm each day, and 25 or more each day. Since one gram of tobacco is the equivalent of one cigarette, these categories rcprcsent groups averaging less than one package per day, “about one package” TABLE: VIII PREVALEXCE OF SPECIFIED RESPIRATORY SYXPTOMS ~~091; \~HITE POSTAL $YORKSRS: NON-SMOKERS COMPARED WITH SXOKERS OF CIGARETTES ONLY AND SMOKERS OF CIGARS AND/OR PIPES ONLY, BY AMOLXT POKED PER DAY: PERCENTAOE OF POSITIVE RESPONSES TO QVESTIOSSAIRE ITEMS Smoking Nonsmokers <15 gm

Symptoma Total

number

interviewed

Persistent cough (5) Persistent phlegm (10) Exacerbations (12b, c) Dyspnea 2 + (14a) Dyspnea 3 + (14b) Persistent wheezing (15~) Persistent nasal catarrh (20) Chest illnesses past 3 years (21) Asthma (22) Persistent cough and phlegm (5, 10) Persistent cough, phlegm and exacerbations (5, 10, 12b, c) Persistent cough, phlegm and dyspnea 3+ (5, 10, 14b)

Cigarettes

category

0nlybJ

15-24 gm

864

Cigars

and/or

pipesd

<15 P

15-24 gm

25+

855

221

116

lY4

39.2 39.3 13.9 41.2 3.8 9.7 27.4 19.4 2.6 29.0

9.5 17.7 10.0 21.4 2.3 0.9 15.0 18.2 2.7 3-9

13.8 15.5 10.3 31.9 1.7 3.4 17.2 19.0 3.4 6.9

18.1 “2.6 9.6 29.4 2.3 3.4 19.2 13.6 2.3 10.7

25+ ml

gm

697

SO6

6.5 13.3 9.2 19.5 1.9 1.3 15.5 16.1 3.3 3.9

13.2 16.5 9.2 23.4 2.3 2.6 17.8 19.8 3.0 9.6

1.4

3.3

.i 3

8.2

0.9

2.6

2.3

0.1

1.3

1.1

1.6

-

-

0.6

25.9 27.2 12.9 31.3 2.1 5.0 19.2 16.2 2.7 17.6

‘I Numbers following symptoms are quest.ionnaire item numbers. h Excludes 2 smokers of cigarettes only with amount smoked unknown. c Since 1 gram of tobacco is the same as 1 cigarette, these amounts refer to less than cigarettes per day, 15-24 cigarettes per day, and 25+ cigarettes per day, respectively. d Excludes 2 smokers of cigars/pipes only wit,h amount smoked unknown.

1.5

274

P. M.

PREVALENCE

OF

DENSEN,

SPECIFIED

E. W.

JONES,

H.

E. BASS,

AND

J. BREUER

TABLE IS SYMPTOMS AMONG SON-WHITE POSTAL WORKERS: WITH SMOKERS OF CIGARETTES ONLY AND SMOKERS ONLY, BY AMOUNT SMOKED PER DAY: PERCENTAGE RESPONSES TO QUESTIONNAIRE ITEMS

RESPIRATORY

NON-SMOKERS COMPARED OF CIGARS AND/OR PIPES OF POSITIVE

Smoking CigareUes

Iion-

category

only6

Cigars

and/or

pipes

only

smokers <15 gm

Symptoma Total

number

innterviewed

Persistent cough (5) Persistent phlegm (10) Exacerbations (12b, c) Dyspnea 2 + (14a) Dyspnea 3+ (14b) Persistent wheezing (15~) Persistent nasrtl catarrh (20) Chest illnesses past 3 years (21) Asthma (22) Persistent cough and phlegm (5, 10) Persistent cough, phlegm and exacerbations (5, 10, 12b, c) Persistent cough, phlegm and dyspnea 3f (5, 10, 14b)

1524 gm

324

25+ gm

<15 gm

15-24 gm

‘J5+ gm

111

64

39

22

18.3 23.9 14.9 25.8 0.6 3.7 15.5 19.9 5.3 12.1

33.0 35.7 19.1 36.5 1.7 9.6 27.0 24.3 4.3 20.9

5.6 9.3 3.7 13.0 1.9 1.9 5.6 16.7 5.6 1.9

10.3 10.3 2.6 18.0 2.6 5.1 15.4 20.5 7.7 10.3

13.6 13.6 9.1 27.3 -

‘2 i

3.i

9.6

1.9

1 .:5

0.3

1.i

-

206

227

8.5 12.1 7.3 22.4 1.5 2.9 7.8 11.7 6.3 4.4

11.6 15.6 8.4 14.2 1.8 5.3 12.0 18.7 3.6 7.6

2. 4 1.0

4.5 4.5 13.6 9.1 4.5 4 5

‘1 Numbers following symptoms are questionnaire item numbers. * Since 1 gram of tobacco is the same as 1 cigarette, these amounts refer to less than cigarettes per day, 15-24 cigarettes per day, and 25f cigarettes per day, respectively.

15

per day, or more than one package per day. Percentages of non-smokers with the specified symptoms are also shown in these tables, for ready reference. The association of increased prevalence of persistent cough and phlegm with increased numbers of cigarettes used daily is very evident. The relationship is observed in both survey groups, both races, and both types of smokers. Among cigarette users, even t.he “light” smokers (under 15 gm/day) report prevalence of cough and phlegm greater than that reported by non-smokers. In the cigarette smoking group also, cough and phlegm prevalence is more than twice as high (in some instances, even three times as high) among “heavy” smokers (25 or more grams per day) as it is among light smokers. It is also of interest that, even when amounts of tobacco used arc comparable, cigarette smokers generally reported grcat,er prevalence of persistent, cough and phlegm than did cigar and pipe smokers. Figure 1 pictures the dramatic rise in prevalence of chronic productive cough with increasing amounts smoked. In this graph, data for ex-smokers are shown also, and are observed to fall between the prevalence figures for non-smokers and those for smokers. III all four categories of rntln (white and non-white, postal and transit workers),

RESPIRATORY

DISEASE

IN

NEW

YORK

275

CITY

TABLE s PREVALESCE OF SPECIFIED RESPIRATORY SYMPTOMS AMONG WHITE TRANSIT WORKERS: XON-SMOKERS COMPARED WITH SMOKERS OF CIGARETTES ONLY AND SMOKERS OF CIGARS AND/OR PIPES ONLY, BY AMOUNT SMOKED PER DAY: PERCENTAGE OF POSITIVE RESPONSES TO QUESTIONNAIRE ITEMS Smoking Cigarettes

X011-

category

onl+

Cigars

and/or

pipes

only

smokers Symptom” T’olnl slumber

interviewed

666

Persistent cough (5) 6.2 Persistent phlegm (10) 9.5 Exacerbations (12b, c) 5 0 Dyspnen 2 + (14s) 12.8 Dyspnea 3+ (14b) 0.6 Persistent wheezing (15~) 0.6 Persistent nasal catarrh (20) 8.4 Chest illnesses past 3 years (21) 11.6 Asthma (22) 2.1 l’ersistent cough and phlegm 2.3 (5, 10) Persistent, cough, phlegm and 0.5 exacerbations (5, 10, 12b, c’l I’rrsistent cough, phlegm and 0.2 dyspnea 3+ (5, 10, 14b)

< 15 gm

15-24 w

25+ iP

<15 f4m

15-24 gm

25f gm

&!I

1,401

862

861

182

168

22.5

39.4

‘L2.6 9.1 22.2 1.1 4.9 14.7 18.1 2.3 14. I

35.6 10.3 32.3 2.8 9.0 22.0 18.4 2.3 27.0

6.5 11.1 3.1 11.8 1.1 1.1 8.4 12.3 2.3 4.2

11.0 18.1 6.6 17.0 -

16.7 16.1 10.1 14.9 0.6 5.4 14.3 14.9 1.S 10.1

1.4

3 .2

6.4

1.1

0 5

0.6

2.0

0.4

12.8 14.8 6.4 15.5 1.4 3.0 9 .3 16.4 ‘2 3 6 X

3.3 10.4 13.2 2.2 9 .3 ‘2 ‘2

4.2

U IUumbers following symptoms are questionunire item numbers. b Excludes 1 smoker of cigarettes only with amount smoked unknown. c Since 1 gram of tobacco is the same as 1 cigarette, these amounts refer to less lhau cig:Irctirs prr day, 15-24 cigarettes per day, and 25+ cigarettes per day, respectively.

POSTAL

Fro. 1. Percentage (Q5j-(110). arcording

of postal to smoking

WORKERS

TRANSlT

and transit workers reporting catrgory, hy race and amount

WORKERS

persistent cough smoked per do?.

and

phlegm

1.5

276

I'. >I. DESSEN,

E. W. JONES,

H. E. BASS,

ASD

J. BREUER

TABLE XI PREVALENCE OF SPECIFIED RESPIRATORY SYMPTO.~~ ,431:)~~ NOS-WHITE TR.4NSIT WORKERS: NON-SMOKERS COMPARED WITH SMOKERS OF CIKARETTES ONLY AND SMOKERS OF CIGARS AND/OR PIPES ONLY, RY Abf~~~~ &OILED PER DAY: PERCENTAGE OF POSITIVE RESPOXSES TO @JESTIONSAIRE ITEMS Smoking Nonsmokers Symptoma -~

Total

number

inter&wed

346

Persistent cough (5) 6.9 Persistent phlegm (10) 9.5 Exacerbations (12b, c) 8.1 Dyspnea 2f (14a) 11.6 Dyspnea 3+ (14b) 0.9 Persistent wheezing (15~) 0.9 Persistent nasal catarrh (20) 9.2 Chest illnesses past 3 years (21) 12.7 Asthma (22) 5.8 Persistent cough and phlegm 3.2 (5, 10) Persistent cough, phlegm and 1.2 exacerbat.ions (5, 10, 12b, c) Persist,ent cough, phlegm and dyspnea

3+

Cigarettes

category

only*~c

Cigars

and/or

pipes

only

<15 gm

15-24 gm

25f fm

91

41

26

32.8 28.6 12.6 25 ‘2 0.8 6.7 23.5 13.4 3 .4 “1.0

8.8 9.9 3.3 14.3 1.1 6.6 11.8 4.4 5 .5

4.9 9.8 7.3 14.6 2.4 12.2 12.2 2.4 4.9

22. 7 27.3 9.1 13.6

2.4

.j 9

1.1

2.4

4.5

0.5

-

<15 gm

lP24 P

“5+ w

359

574

118

7.5 13.1 7.0 10.6 0.3 1.7 8.4 12.8 3.1 5.0

15.8 20.7 10.3 16.8 0.9 4.2 14.8 19.0 3.0 12.4

1.9 -

4.5 13.6 3 .2 13.6

-

(5, 10, 14b)

n Kumbers following symptoms are questionnaire item numbers. * Excludes 1 smoker of cigarettes only with amount smoked unkllown. c Since 1 gram of tobacco is the same as 1 cigarette, these amounts cigarettes per day, 15-24 cigarettes per day, and 25+ cigarettes per day,

refer to less than respectively.

15

increasing symptom prevalence is also aysociatcd with increased numbers of cigarettes smoked when t,he symptom reported is recent, exacerbations of cough and phlegm, any degree of dyspnea, or persistent nasal catarrh. For other symptoms and for these and other symptoms reported by cigar and pipe smokers, the association between prevalence level and amounts smoked is less marked, or in some cases (notably ast,hma) nonexistent. -4 further important point in this set, of four tables is that the excess prevalcncc of cough, phlegm, and shortness of breath among white cigarette smokers as compared with non-white cigarette smokers, which was observed previously, is still evident when groups of white and non-white men averaging like numbers of cigarettes are compared.

The age distributions of men in the two study City survey are very different. Although 43% of under 40 years of age, and a total of 8170 were cent.ages of transit’ workers interviewed were only

populations of the New Tork the postmen interviewed were under 50, the comparable per24 and 61, respectively. Within

RESPIRATORY

DISEASE

IX

NEW

YORK

277

CITY

t8hcac two groups different. age distributions were found for white and non-white men. Age patterns were also different for men in the various smoking categories with, for example, a notable lack of young men among cigar and pipe smokers. Therefore, age-specific rates are necessary not only to examine the relationship of age to t,he prevalence of respiratory symptoms but to evaluate the possible influence of age difference on pattern s already described for postal and transit, white and non-white worker? within specific smoking categories. Such rates for cough and phlegm prevalenrc (Q5 and QlO) are shown in Table XII and Fig. 2. All along the age scale, percentages of men with cough and phlegm remain higher among cigarette smokers than among other groups, with the percentages only slightly higher for cigar and/or pipe smokers than for non-smokers. Also, among cigarette smokers in each age group the higher rates for postal than transit workers , and for white than non-white in the respective work groups, were still obstr\.td. Although there is a suggestion of an increase in cough and phlegm prcvalcncc l)c+ween the age groups under 35 and those over 35 who arc cigarette smokers, the pictures presented for the other smoking categories arc either of no increase with age or of a decreasing prcvalrncc with age. Caution must bc cxcrcised here because of possible cohort effects. SclcctiT-c removals from each category, and possibly Wlectivc admissions to Wch, might also combine to produce a complex sit,uation. The picture of prevalcncc of cxncerhations of cough and phlegm lasting thr(te TABLE PERCENTAGE PHLEGM

OF POSTAL

(Q5

AND QlO):

AXI)

TRANSIT

XII

WORKERS

AWORDING

TO

SMOKING

Percentage

REPORTING PERSISTENT CATEGORY, RY RACE with

SUIW

,Smoking category, work group, and race

her interviewed

All ages

I’nder 35

persistent cough (Q5 and QlO)

COUGH AND

ASI)

AGE

and phlegm

35-39

40-44

45-49

50-54

,x-59

60 and over

14.3 10.2 10.8 i ~3

23.0 13.9 17.1 11.4

24.5 12.4 17.0 13.6

“3.S 12.7 19.2 1'2.0

23.9 15.4 17.6 14.6

23.8 17.9 14.8 15.6

(35.(l),’ NS’J 19.6 xs

C!ignret,te smokers Postal White Xon-white ‘I’r:ulri( White Son-white

2 , o”5 6;” 2,693 1,062

(‘&r/pipe smokers Post:11 White Xon-white ‘I’ransi t White Non-white

513 115 611 154

7,s 5 ,2 7.4 6.5

2.6 NS NS ?;S

10.3 (6.7) 16.7 7.7

7.2 SS 5.6 X.8

5.3 19.5) 4.x 8.1

10.6 (8.7) 5.3 4.0

11.6 (0.0) 7.9 cO.Oj

(G .3) KS 7.6 NS

69i 20G 666 346

4 0 4.4 2.3 3 2

2.3 2.2 2.2 2.9

7.2 i.7 1.5 1.2

4.4 6.9 1.8 2.7

4.0 NS 3.1 4.7

2. 6 (4.3) 1.9 3.4

5.9 NS 2.9 NS

(0.0) (0.0, 1.5 NS

Sever

smoked Postal Transit

White Non-white White Non-white

21.:; 12.1 Ii.0 10,s

a Parentheses indicate that rates are baaed on only * NS, rates based on fewer than 15 men not shown.

15-24

men.

278

P. M.

60,

DENSEN,

CIGARETTE

E. W.

JONES,

SMOKERS I

H.

E. BASS,

PIPE AND CIW 7-

AhiD

J.

SMOKERS

BREUER

NEVER

SMOKED I

. . . . ..-... .---.,_.” _

POSTAL WORKERS WHITE POSTAL WORKERS NON-WHITE TRANSIT WORKERS WHITE TRANSIT WORKERS NON- WHITE

.____

240

I

0

30

35 40 45 50 55 60

30 35 40

AGE

45 50 55

60 30 35

40 45

AGE

FIG. 2. Percentage of postal and transit (Q5 + &IO), according to smoking category, with total frequently less than 15 men.)

workers by rare

50

55 60

AGE

reporting and agr.

persistent (Data not

cough and phlrgm shown for age group*

weeks or more in the last three years (questionnaire it.em 12b, c) (Table XIII, Fig. 3) is quite different from that of habitual cough and phlegm. As previously noted, the difference in rates among the three smoking categories is small. There is also little difference from one age group to another, and differences between postal and transit, white and non-white, show no consistent pattern. Age-specific findings on prevalence of shortness of breath (item 14, 2+) TABLE PERCENTAGE

OF POSTAL ACCORDING

Smoking category, work group, and rare

AND

!~ANSIT TO SMOKING

Number interviewed

XIII

WORKERS

REPORTING

Percentage All ages

ITndcr 35

X-39

with

40-44

(&12a,c):

EXACERBATIONS

RY RACE

CATEGORY,

AND

AGE

exacerbations

45-49

(&12b,

50-54

c) 60 and over

55-59 ___-

Cigarette smokers Postal White

12.8 13.4 9.0 9.4

12.0 14.3 6.4

1.5.X 18.0

14.3 11.5

White Xon-white

2,025 662 2,693 1,052

12.2

10.2

8.0

10.7

smokers White Non-white White Non-white

513 115 611 154

9.9 4.3 6.1 5.2

10.3 NS SS NS

697 206 666 346

9.2 7.3 5 .o

11.6 6.7 3.2

Non-white

Transit

Cigar/pipe Postal Transit

Sever

smoked Postal Transit

White Non-white White Son-white

X.1

9 s

a Parentheses indicate that rates are based on 15-24 h NS, rates hascd on fewer than 15 men not shown.

15.0

(15.O)U

11.1

6.2 8.2

9.6 9.6 9.7 6.7

3.6 7.3 12.5

SSb 13.2 ss

11.5 (0.0) 16.7 :3 Y

14.4 NS 5.6 5.9

9.6 (4.8) 7.1 5.1

6.4 (4.3) 9.2 0.0

i.0 (10.5) 2.Q (12.5)

(0.0) NS 2.2 NS

11.7 15.4 10.6 7.3

8.8 10.3 4.4 6.8

8.7 X-3 4.6 7.0

5.2 (4.3) 2.8 6.9

5.Q NS 5.1 NS

(0.0) (0.0) 6.0 NS

men.

10.0 11.3

RESPIRATORY

6.

CKXRETTE

DISEASE

SMDKERS

IX

NEW

YORK

279

CITY

NEVER

PIPE AND CIGAR SMOKERS

SMOKED

‘i 0’

” 30. 35

” 40 45 50 AGE

” 55

60

3Ok40 ’

45 50 AGE

55

60 30

35

40

45 50 AGE

55

60

FIG. 3. Percentage of postal and transit workers reporting exacerbations (Q12 b, c), a~cording to smoking category, by race and age. (Data not shown for age groups with total frequency Icss than 15 men.)

(Table XIV, Fig. 4) are markedly different from those of other symptoms clicitcd by the questionnaire. White cigarette smokers in both postal and transit groups and non-(white cigarette smokers in the Post Office, reported marked increase in prevalence of dyspnea at older ages. White postmen smoking pipes and/or cigars reported a similar age differentiation but with age-specific rates below those for their cigarette-smoking counterparts. Age-specific rates for non-smoking white TABLE I%R~ENTAGE

OF

SIT

POSTAL AND TRASSIT WORKERS REPORTING BREATHLESSNESS ACCORDING TO RMOKlSG %TEGORY. RY RACE AND AGE

(Ql4,2+):

~~~ ~

~

Smoking category, work group, and race

Kumber interviewed

AI1 Under ages 35 35-39 4&44

45-49 50-54 55-59

60 and over

Cigarette smokers Postal White Non-white Trarrsitj White Non-white

2,025 662 2,693 1,052

34.4 2’7.4 23.7 18.5 24.3 14.7 1.5.6 14.2

38.4 22.5 25.5 20.3

(55.0)~ N&Y 27.9 3-S

Cigar/pipe smokers Postal White Non-white Transit White iSon-white

513 115 611 154

26.5 17.4 14.2 14.3

12.8 24.4 26.1 25.8 30.9 37.2 NS (13.3) NS (23.8) (21.7) (15.8) NS 26.7 16.7 11.9 18.3 11.4 NS 1.5.4 14.7 13.5 16.0 (6.3)

(25.0) NS 9,s ss

697 206 666 346

19.5 20.9 12.2 1o.i

16.8 15.6 4.3 4.9

(25.0) (26.7) 14.9 NS

Sever smoked Postal Transit,

White Non-white White Non-white

Percentage wit’h breathlessness (Q14, 2 f)

33.3 31.1 22.6 14.8

15.3 15.4 13.6 11.0

a Parentheses indicate that rates are based on 15-24 men. b NS, rates based on fewer than 15 men not. shown.

34.0 21.2 23.8 16.6

24.1 24.1 14.2 15.1

42.1 23.1 24.2 11.2

20.8 23.4 NS (26.1) 12.3 11.2 16.3 10.3

48.5 46.4 27.8 15.6

11.8 NS 11.7 h-s

280

P. M.

60

’ 30

FIG.

4. Percentage to smoking frequency less than

cording

DENSEN,

CIGARETTE

35

40

E. W.

SMOKERS

45 50 AGE

55

JONES,

H.

E. BASS,

AND

PIPE AND CIGAR SMOKERS

60

30

of postal and transit category, by raw and 15 men.)

35

40

45 50 AGE

55

M,

J. BREUER

NEVER

30

35

40

SMOKED

45 50 AGE

workers reporting breathlessness age. (Data not shown for age

55

60

(Q14, 2+), groups with

actotal

postmen and transit wokrs are generally lower than comparable rates in other smoking categories, and among these non-smokers the prevalence level changes very little across the age scale. Non-white transit workers fit none of these descriptions. In this group, except for a low rate of dyspnea among non-smokers under 35 years of age, the prevalence of the symptom is very little affected by either smoking category or age. Numbers of non-white transit workers in specified age groups among non-smokers, and also pipe smokers, however, NC relatively small. The effect of a multiplicity of variables, such as age, race, and smoking charncteristics, is to make comparisons between survey groups difficult. In TtLble XV, the data are given for postal and transit survey groups adjusted for differences in the distributions of the respective populations on these variables. The effect of the calculation (comparing the “adjusted” rates with the observed prevalence data in Table IV) is to widen the difference between Post Office and Transit rates for all questionnaire it’ems except phlegm during the day or night (8), exacerbations of cough and phlegm in past 3 years (12b, c) wheezing with colds (15a), chest illnesses causing absence from work in past 3 years (21), asthma (22) and history of hay fever (23). Thus, the observed differences between the two survey groups in prevalence of all other symptoms as defined by questionnaire items (with the Post Office rates consistently higher than the Transit) are not due to differences in composition of the st,udy populations, with respect to age, race, or broad smoking category. Symptoms

and Occupation

The relationship between the working environment and respiratory disease symptomatology is a matter of concern to all of the agencies cooperating in this st.udy. The general nature of the working environment of the men included can be described as follows. Letter carriers in Manhattan and the Bronx spend a relatively small fraction of their working day in postal stations and the remainder on their respective

CITY

281

routes in the two boroughs. Routes vary even within a Manhattan! a single large building may be the locale of route. All but about 30 of the mail truck drivers in this single large garage. The majority of the letter carriers (7 AM-3 PM are hours frequently encountered) ; mail truck starting every 15 minutes around the clock.

borough; in midtown more than one entire study work out of a work daytime shifts drivers work on shifts

RESPIRATORY

DISEASE

TABLE ~EV.~I.ENCE

IN

NEW

YORK

XV

OF RESPIRATORY SYMPTOMS AMONG POSTAL .4iw TRASSIT PERCENTAGES WTA SPECIFIED SYXPTOMS, ADJUSTED FOR .-ICE. RAPE, ANT) SXOKIXG CATEGORY

WORKERS:

Adjusted percentages* Sympt0m.s~ Number observed

in

each

group

Cough, AM (1) Cough, day/night (3) Persistent cough (5) Phlegm, AM (6) Phlegm, day/night (8) Persistent phlegm (10) Exacerbations (12b, r) Dyspnea 2 + (14a) Dyspnea 3+ (14b) Wheezing (15) Wheezing with colds (15a) Wheezing without colds (15b) Wheezing most days (15~) Weather affects chest (15) Weather causes dyspnea (17E) Kasal catarrh (18) Persistent nasal catarrh (20) Chest illnesses past 3 years (‘2 1 I Asthma (22) Hay fever (‘13)

Postal workers 6,310

19.8 25.5 20.7 27.2 28.3 24.0 11.0 30.3 2.9 26.i

21.1 13.1 5.4 10.9 5.1 31.7 18.4 17.6 :3.6 9.1

a Numbers following symptoms are questionnaire item numbers. 6 Adjusted to the a,ge-race-smoking category distribution of the rombined population groups.

Transit workers r,186 15.6 20.3 16.4 21.4 23.4 18.7 3.2 18.0 1.2 25.0 21.9 8.5 3 5 6.7 2.i 24.5 13.6 16.6 ‘2 .8 7 .5 postal and transit

Bus drivers in the survey population work out of 10 depots which are located in -Manhattan (l), Brooklyn (6), Queens (2), and Staten Island (1). Bus routes are circumscribed only in that they tend to be contained within the borough of origin. Most of the drivers are on the city streets during periods of heaviest traffic concentration, since the system is designed to move passengersduring morning and evening rush hours. Subway motormen have the specific environment of the subway tunnel; their runs, like the subway lines themselves, may extend from one geographic extremity of the city to another. In Table XVI, the prevalence of cough and phlegm is shown for two distinct srnol\-ing categories (non-smokers and cigarette smokers) for white men and non-

282

P. AI.

DENSEN,

E. W.

JONES,

K.

TABLE

E. BASS,

AND

J.

BREUER

XVI

PREVALENCE OF PERSISTENT COUGH AND PHLEGM AMONG POSTAL AND TRANSIT WORKERS 35 YEARS OF AGE OR OLDER, BY OCCUPATIOX .IND R.~cE IN Two SMOKING CATEGORIES

White Postal

Symptom”

Non-white Transit*

Letter Truck car- drivriers ers

Bus tlrivers

Postal

Mot,ormen

Transith

Letter Truck car- drivriers ers

Bus drivers

RIotormen

Percentage of non-smokers with specified symptom Number qf men

508

Persistent, cough (5) 7.5 Persistent phlegm (10) 13.6 Persistent cough and phlegm (5 and 10) 4.5

16

33.3

228

84

52

158

93

10.7 10.7

9.4

15.6

14.0

4.8

9.4

8.0 8.7 3.6

NS

5 1

7.5

NS SS

7.2 1.5

12.7 3.1

6.5 3.2

Percentage of cigarette smokers’ wit.h specified symptom Number

of men

1,698

128

1,782

90s

Persistent cough (5) 32.2 Persistent phlegm (10) 33.7 Persistent cough and phlegm (5 and 10) 23.4

32.0 34.4 25.0

27.9

25.8

24.4 24.7

17.6

16.4

3.46 1x3 19.7 24.3 13.9

554

279

21.1

16.8

21.2

22.6 12.0

21.1 11.6

23.4 14.7

a Numbers following symptoms are questionnaire item numbers. * Does not include interviews of men newly employed in specified categories after February 10, 1962. c KS, percentages not shown because of small number in category. *’ Includes smokers of mixed types (cigarettes plus pipes and/or cigars). 113en, 35 years of age or older, in t.lle occupational groupa tlcscribecl. (Bus dispatchers are not shown becauseof their relatively small number.) Among cigarette smokers, prevalence of cough and phlegm is very similar for the two different occupations within each industry; this is true for white and non-white men alike. In this smoking category also, racial differences observed previously are maintained within specific occupational groups. Non-smoking postal truck drivers arc too few in number to permit comparison with non-smoking letter carriers. In the non-smoking transit group, however, phlegm production was reported slightly more frequently by motormen than by bus drivers. Since the average age of motormen is older than that of bus drivers, a special analysis was made of symptom prevalence among white transit workers in these two occupational groups adjusted for both age and smoking category. In this analysis the adjusted percent,agesfor individual symptoms were very similar throughout, although percentages for motormen were still slightly higher for phlegm production, especially during day or night, (motormen 26.570, bus drivers 21.3%). and recent exacerbations of cough and phlegm (9.1 and 6.870, respectively). White

RESPIRATORY

DISEASE

IN

XEWT

YORK

CITY

283

crnd Residence In view of currcllt intcrcst in t,hc possible relationship between rcsi+atorY disease illnesses and ambient air pollution, analysis of prevalence data by Illacc of residence as well as by occupation was one of the objectives of the survey. A logical CIassification wound be based 011 Icvels of pollution within the city and other arcas of rcsidcncc. Such d&a on air pollution; liowcver, were unfortunately lacking. Plncc of rcsidencc at the time of intcrvic1v, therefore, was the only criterion a~ailahlc for catcgorizin, v environment, a~vay from t.he job. The study of respiratory symptom prevalence according to borough of rcklencc and for combined residences outside tllc city by race, smoking patterns anti :I@, revealed no cvidcncc of a consistent pattern of differcnccs among the geographic areas selected. Thcrc was little variat#ion from one area to another; furthermore, within cnch area, both high and low ratre wcrc ObscrVCtl.

Synzptonas

DISCUSSION

The primary purpose of t,his survey of rcnpiratory cliscasc symptoms among New I’ork transit and postal workers was to obtain a measure of the extent of the problem of respiratory disease among t.hcsc working populations, and to search for characteristics of high risk individuals. Most descriptive of the o~rall findings of the tstcnt of the respiratory discasc problem is the fact that 12-15% of the white and 9-10% of tlic non-white nicn reported persistent productive cough in terms that arc consistent with clinically Mined chronic bronchitis. Contributing to the identification of intlividual~ ill high-risk categories was the for certain subgroups of finding of distinctive pattern P of syn~ptoiii prcvalcnrc the populations survcyctl. Thr widest r:rngc I)c%x‘ccn higIl a~1 low ~~rc~~~al~~.~r:itcs was found whrn the data wcrc analyzccl according to smoking pattcrllr. Cigarette smokers rcportcd 1iaCng chronic rough and phlegm about. fi\c timcls iis frcqucntly as men who had ncvcr smoked. .\inong postmen, t’hc pcrccntagt 1s with cough and phlegm wcrc 19 for cigarcttc smokers and 4 for non-smoker’. q , among transit workers, comparable pcrcrnt;~g~s uxw 1.5 and 3. Furtllcrmorc, prevaltnce of symptoms increased with inerrasing amounts smoked. Cough and phlegm were present more than twice as frequently among heavy bmokcrs (mow than two l~ckagcs per day) :ts among light smokers (less than one package per day). Apparent tliffercnccs in preralencc of symptoms wcrc also found in comparisons of white men ancl non-white men, almost at1 of whom are Negroes. In the Post C)ffirc, 15% of the lvhitc men had chronic bronchitis, but, only loo/, of the non-white men were in this category. Liken-kc, among transit workers 12% of the white alld 9% of the non-white had symptoms of chronic bronchitis. In this connection it is interesting to note that the combined death rates from chronic fxonchitis and cmphyscma in New York City in 1964 were 14.1 per ~OO,CQO population for white males and 8.9 per 100,000 population for other males, a ratio of 1.6 to 1.” ~Vhcthcr prcvalcncc data and mortality rates indicate a rliffcr3Deatl~ rates 1964 by the 1960

lvere calculatedby dividing the number of deathsfrom specifiedcauacsin population.

284

P. M. DENSEN,

E. W. JOKES,

H. E. BASS,

AND

J. BREUER

ence of this magnitude in actual occurrence of chronic obstructive lung disease in the two populations is not known since each of these rates is dependent on a number of variables. Detailed study of the data on cough and phlegm (for postmen) showed a widening difference between the two races with increasing severity of symptom. The differences as described were due largely to differences among cigarette smokers of the two racial groups; furthermore, the increased presence of cough and phlegm among white cigarette smokers as compared with non-white, was still evident when men of t,he two racial groups averaging the same amounts smoked were compared. Among non-smokers, however, symptom prevalence was similar for white and non-white men. The significance of these apparent racial differences in respiratory disease symptoms merits further study. Comparisons of the data for white and nonwhite men will be presented in grent,er detail in a later report on data from this survey. Determination of prevalence of respiratory disease symptoms among groups of men with different environmental exposures was another aim of this study. Occupational categories examined included letter carriers and mail truck drivers in the Post Office and subway motormen, bus drivers, and bus dispatchers in the Transit Authority. blthough the differences in percentages of men reporting specified symptoms among the combined postal workers and among the combined transit workers were not large, the percentages of postmen with specified symptoms \vere consistent,ly higher than comparable percentages of transit u-orkers. Also, although the two employed groups differed markedly in their age distribution, the prevalence rates adjusted for differences in age, smoking category, and race were still higher for the postal group than for the transit. Within each of the employee groups, howevrr, no significant difference between occupational categories was discernible. Taking into account these two findings, that the two major study groups differed slightly but consistently in prevalence of symptoms, but that occupational groups within each major study group did not differ from each other, it is our impression that the increased prevalence of symptoms among postal workers is not attributable to differences in the occupational environment but could be due to factors of selection of the employed populations. It is not possihlc! for example, to rule out the effects of differences in personnel management relating to pre-employment and periodic medical examinations or of selective remoyalr for other reasons from the employed populations. Cohort effects are cxt,remely difficult to estimat.e without detailed analysis of factors inrolved in initial selection of employees and subsequent withdrawals from the groups under study. The question of possible differences in occurrence of symptoms among men with different residential environments was also examined. In the absence of data on air quality for different sections of New York City, analysis of prevalence data was made by borough of residence. No consistent pattern of differences, which could be related to these large geographic areas, was observed. The lack of findings here, of course, does not mean that the association was nonexistent, but that. the means for tcst.ing it were.

RESPIRATORY

DISEASE

IX

SEW

YORK

CITY

285

The experience of t,his survey has revealed two problem arcas of importance in the planning of future studies such as this. First, because smoking has proved to be the most important factor in delineating high- and low-risk groups, the total number of persons to be examined should be large enough to supply adequat’c numbers of nor\-smokers to permit the further subgrouping that the analysis will require. In t,his study it was found that only 157:: of the total sample were nonsmokers. Although 12,604 mrn were intervicwtd thcrc wert, for example, 0111~’ among the non-white postal workers. Further subdivision on 206 non-smokcrr parameters of niultil~lc categories, such as age, $0 dccimatcs the group that analysis beyond this point is difficult,. Since non-smokers, as representatives of the “low-risk” groupt play a vital part in comparisons of relative risks, a lack of sufficient numbers of non-smokers ran prcsrnt :I serious handicap in Ardics of respiratory disease. A second problem is posed by the riced for more prrcisc measure+ of cnvironmental exposures, t)oth as related to pollution of the ambient air an(l to in~lividualized pollution by cigarette-smoke inhalation. In this Amy, hccau~c of tlic 1nVli of specific mrasurcs for air pollution factors tither on the job or at home, c~nvironnrcnt could be described only in terms of jot, classification or broad :(rca of rcsidcncc. The fart that no correlation could bc ticmonstrntetl clock riot llIc:111 t 112 t, c~nvironmcnt l~laps no part in respiratory tlisctase in the pol)rrlations &iclic[l. Itatllcr it pointa up the need for tlic tlcvclol~n~cnt of inore prrcise mcasllrts Of indi1.itlual csl)Osurc to specific pollutants. The clcmonstration of rigrrificfi:ult r~~lationrhil~s l)ctwccn tlisease in the ~on~niunity ant1 air r~nvironruc~rit will tlcpcW(l 01) ~~1’0~1~cas ton:lrtl solution of tllis l~rob1~~m.

The cl:(t:i in this rchl)ort. on the preval~~nc~c of rc~~~l~ir;ctory tliscase symptoms arc 11asc~l 011 intcrl-icns with 4,107 white an11 1.203 non-white postal workers, 5,335 mhitc and 1,951 non-Ivhitc transit workcr~. Of mien tl~~frnctl as eligible for inclusion in the survey, intcrviclws were obtainccl for 87.472: of postmen and 81.3% of t#ransit, workers. Chronic bronchitis, clcfinctl as “pcrsistcnt cough on most days for 3 months of t.hc year for :\I least 2 years,” was reported among 15% of white compared with 10% of non-~llitc postal workers, and among 127:, of white compared with 9cjo of non-whitr transit, w~rkcrs. Chronic cough ant1 phlegm in combination were tepot.tt(l five times more frccluently by rigarcttc smokers than by non-smokers. Rates for bc:\vy amolrcrs (more than two packages per day) were more th:rrr twicp thos;c for light smokers (less than 011~p:~clr:tge prr day). The higher pre\-alrrrc~s rates for wllitc :IS romparcd with non-wbitc men were found to occur l~rinlurily among cig:(rcttc smokers. The differcnccs held true when lvhite and non-whit r nicn smoking similar amomit’s WI’C compared. But rams: for rlonstnokccific job category or place of rcsidcnce and symptom prevalence point:: up the neetl for more refined measures of individual exposurr5 to specific dcgrccs and kinds of air pollution than are now available. Furthrr reports on data from thi- cc survey will cOTw pulmonary function t(+,

286

P. M.

DENSEN,

E. \I-.

JONES,

H.

E. BASS,

AND

J.

BRECER

a more detailed study of apparent race differences, and an analysis of absenteeism records of transit workers correlated with survey findings. Follow-up studies of high risk and other sub-groups from this survey are now in progress. ACIiNOW-LEDGMENTS The authors wish to rxprrss their for valuable assistance in this study.

gratitude

to Mrs.

Gloria

Block

and

Miss

Elizabeth

Rerd

REFERENCES THORACIC SOCIETY, Committee on Diagnostic Standards for Nontuberculous Rrspiratory Disease. (1962). Definitions and classification of chronic bronchitis, asthma, and pulmonary emphysema. Amel. Rec. RPSP. Dis. 85, 762. AXDERSOK, D. O., AND FERRIS, B. G., JR. (1962). Role of tobacco smoking in the causation of respiratory disease. New Eng. J. Ned. 267, 787-794. BRITISH MEDICAL RESE.~R~II Conscrr., Committee on thr~ Aetiology of Chronic Bronchitis. (1960). “Instructions for the VW of the Questionnaire on Respiratory Symptoms.” Pamphlet published by the British Mediva Rr~nrch Council. D~.i,v, M., GOLDSMITH, J., .4NL) Tr.xr.1, D. (1965). Respiratory conditions in otit~itlt~ \borkcrs Arch. Enz,iron. IIealth 10, 323-331. DENSEX, P. M., BREUER, J., B.wB, H. 15.. ASD JOSES, E. W’. (1962). Organizational problems in the New York City s:ul’\-cxy for vhroniv rcqkltor)disrnar,. drnt~,~. Hrcl. l/(‘.s/). Dis. 86, 855-857. HOLL~XD, Iv’. u’., AND f+roxl<. 1~. ly. (1965). Rrspirntory disorders in Ihitrd Statvs ~sl c.o:l*t t.t+phone men. J. Epidem. 82, 92-101. MCKERROW, C. B., AXD EDWARDS, P. (1961). The McIirsson Vitalor. J. -4nz. Xcti. Assoc~. 177, 865867. A~muc.4~