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Hypertension control: The role of screening and referral to community physicians
PREVENTIVE
MEDICINE
9, 569-577
Hypertension
(1980)
Control:
Referral
The Role of Screening
to Community
and
Physicians
CHARLES A. NUGENT",' AND BARBARA A. GERLACH~ *Section of Endocrinology, Department of Internal Medicine, University o./’ Arizona College of Medicine, Tucson, Arizona 85724, and tAmerican Heart Association, Southern Arizona Division, Tucson, Arizona 85716 In this trial of one method to control hypertension, adults in a community were screened and those with elevated pressures were referred to their local physicians for management. On a follow-up survey 1 year later blood pressure measurements were obtained on 73% of the patients originally identified as hypertensive. In those rescreened there had been an increase in the proportion of subjects receiving drug treatment for hypertension from onethird to three-quarters. Also, systolic and diastolic pressures were significantly lower. HOWever, the degree of control of hypertension was often inadequate. Of those subjects who initially had disatolic pressures of 10.5 mm Hg or more, only 42% could be classified as having fair to good control of their pressure. Screening patients in a community and referring them to their physicians for management was shown to be a relatively ineffective method for controlling hypertension. Expanded or alternative screening and referral programs need to be developed or increased emphasis placed on prevention to improve on these results.
INTRODUCTION
The American Heart Association, Southern Arizona Division, has a simple goal: to decrease morbidity and mortality due to cardiovascular disease in Southem Arizona. In 1976 we selected control of hypertension as the most practicable method to achieve this goal. Hypertension is a major contributor to the development of cardiovascular diseases and procedures for detection, management, and follow-up seem to be available (24). Before starting a hypertension control program, a trial was undertaken to test one method. Screening was done by the Heart Association. Subjects with elevated blood pressures were told the results, were given pamphlets on the problem, and were referred to their local physicians for management. One year later those patients who had been identified as hypertensive were interviewed and screened again for hypertension. The results of the trial are reported here. POPULATION
AND METHODS
Screening was conducted over 2 days in the city of Yuma (population 30,081) (4). Using figures for the age distribution in the nonmetropolitan counties of the state, the estimate was made that 19,550 of the inhabitants of Yuma were 17 years of age or older (4). The free screening program was publicized by television, radio, and newspaper. The county medical society was told about our program. Screening was conducted by Heart Association employees and trained volunteers. All subjects sat for 2 to 5 min while completing their questionnaire before their blood pressure was ’ To whom reprint requests should be addressed at: 1501 N. Campbell Ave., Tucson, Ariz. 85724. 569 0091-7435/80/040569-09$02.00/0 Copyrisbt All d&s
@ 1!%30by Academic Press. Inc. of reproductionin any f,mn reserved.
570
NUGENT
AND
GERLACH
measured in the right arm of the seated subject. The onset of the fifth Korotkoff phase was used for estimating diastolic pressure. If the blood pressure was elevated above 159 mm Hg systolic or 94 mm Hg diastolic, they were asked to rest for lo- 15 min and a second determination was made. Subjects who were taking antihypertensive drugs, but had borderline or no elevation of their blood pressure, were not classified as having definite hypertension in this study. Subjects less than 17 years old were excluded. Screenees with final pressures exceeding 159 mm Hg systolic or 94 mm Hg diastolic were told that they had high readings and were urged to see a physician promptly. Those who could not afford private care were referred to a public health clinic where charges were adjusted to income and service was free to those eligible. Each person with hypertension was also given two information booklets on hypertension (14, 21). At the time of the screening, hypertensive subjects were also asked if they were taking antihypertensive medicine or birth control pills and if they usually added salt to their food. Subjects were also asked if they were willing to participate and only those who agreed and who signed permission for their physicians to release medical information were included. One year after the initial screening, announcements of the rescreening for those with hypertension were made over television, radio, and in the newspaper. All subjects with pressures exceeding 159 mm Hg systolic or 94 mm Hg diastolic on the initial screening were contacted by mail and telephone and asked to return. At the time of the follow-up blood pressure determinations, subjects were asked if they were taking antihypertensive medications, or birth control pills, or using salt at the table. Hypertensive subjects who did not appear for the follow-up examination were contacted by letter and phone or their physicians’ offices were telephoned in the attempt to obtain follow-up information. RESULTS
Fourteen percent of the adult population of Yuma was screened. After excluding out-of-town visitors, who were unlikely to be available for follow-up examinations, 9% of those screened were hypertensive (Table 1). Analysis of the 226 hypertensive subjects is confined to the 219 who were willing to participate in the study. This segment of the population was predominantly white and included similar numbers of men and women; 89% were more than 44 years old. Sixty-three percent of the subjects usually added salt to their food. None were taking oral contraceptives. The pressures on the initial visit are displayed in Fig. IA and are separated into four degrees of severity of hypertension in Fig. 2A. Of the 219 subjects identified as having systolic or diastolic hypertension, the systolic elevation was definite (2180 mm Hg) or moderate (160- 179 mm Hg) in 70% while diastolic elevations were definite (2 105 mm Hg) in 22% and moderate (95- 104 mm Hg) in 42% (Fig. 2A). One-third of the subjects were taking antihypertensive drugs at the time of their initial screening (Fig. 2A and Table 1). At the l-year follow-up visit, information on blood pressure was available on 160 of the hypertensive subjects (Table 2). Seventy-two percent of the subjects questioned on salt intake said they used salt at the table. Three-quarters of the subjects on whom information was available were on drug treatment for hypertension (Table 2). Again, none took oral contraceptives.
COMMUNITY
HYPERTENSION
571
CONTROL
TABLE 1 POPULATIONON INITIAL SCREENING Number Composition Out-of-town residents Normotensive subjects Borderline hypertensive subjects Hypertensive subjects Refused to participate Signed up to participate
Percentage
118 1,583 799 7 219 2,726
Characteristics Subjects Race White Black Other Sex Men Age (years) 44 45-54 5.5-64 65-74 375 Information on salt Usually add salt to food Information on drug treatment On treatment for hypertension
219 206
216 219
160 173
100 100 83 15 2 100 49 100 11 12 28 35 14 loo 63 100 34
The mean systolic/diastolic pressures of the 160 patients with follow-up data were 177.7/97.5 mm Hg on the initial visit and 153.2/86.8 mm Hg on the l-year follow-up (p < 0.001 for both systolic and diastolic pressures). The severity of hypertension and the proportion of patients treated with antihypertensive drugs are shown in Fig. 2B. At the time of the l-year follow-up, 40% of these subjects now had definite or moderate diastolic elevations. Furthermore, 86% of those with moderate or definite systolic elevations were on drug therapy for hypertension and this was true in 80% of those with elevations of diastolic pressure (Fig. 2B). Of those individuals with definite diastolic hypertension on the initial visit, at the time of the l-year visit, fair or good control of diastolic pressure was achieved in 55%, while for systolic pressure the figure was 42% (Table 3). DISCUSSION Indications
for Drug Therapy for Hypertension
The decision in this hypertension control program to refer all screenees with pressures greater than 160 systolic or 95 mm Hg diastolic to their physicians for management is arguable. Mortality rates do rise with increases in systolic and in diastolic blood pressure (6). But this is not sufficient evidence that treatment
572
NUGENT
1---‘I I I I I I 30 f I 20 -
i I I L-1
rI .--A
o--i
i I
I
’
Data on All Subjects
-7
1
-
htiil
GERLACH
I I-
I J 10
AND
’
’
’
L’ 1
40 c I---I , i
lnitiil
Data on Subiects
Diastolic
B.
for
Systolic BP in mmlig
FIG. 1. Percentage of patients as a function of the levels of systolic and diastolic blood pressure. The results in the total population of 219 subjects initially identified as hypertensive are displayed in (A). The results in the subjects for whom both initial and l-year follow-up blood pressures are available are displayed in (B). Data on the initial and final blood pressures are recorded as dashed and continuous lines, respectively.
would necessarily improve the outcome. The VA Cooperative Study convincingly demonstrated the effectiveness of drug therapy for hypertension in decreasing morbidity and mortality in men with initial diastolic pressures greater than 104 mm Hg (28). In this study it was assumed that physicians should treat all patients with diastolic pressures greater than 104 mm Hg and that most compliant patients would be able to reduce their diastolic pressure to less than 90 mm Hg. Admittedly, not all would agree with our assumptions on the indications for treatment (1, 7, 8) or the goal for therapy (11). Reduction of diastolic pressure, even though levels as low as !I0 mm Hg are not attained, is also of value in reducing morbidity (11). The National Committee on Detection, Evaluation, and Treatment of High Blood Pressure recommends that antihypertensive drug treatment for subjects
COMMUNITY
HYPERTENSION
573
CONTROL
lnitiil Visit
Svstolic
Diastolic A.
BP mmHg
180 or>
160-179
140-159
Absent cl40 r I, resow
Def. 105 or> up Visit
MOI 95-104
Bord. 90-94
Absent ~90
Systolic
0 BP mmHg
Def. l&I or>
Mod.
Bard.
160-179 140-159
Absent 440
Def.
Mod.
Bord.
Absent
105or>
95104
so-94
c9l
FIG. 2. The heights of the columns indicate the percentage of subjects with different degrees of
hypertension. Blood pressures at the time of the initial visit are shown in (A) and at the time of the first year follow-up visit in (B). The shaded areas are the percentage of subjects on drug treatment for hypertension at the time they were seen.
with diastolic pressure of 90 to 104 mm Hg should be individualized with consideration given to other risk factors (24). There are many reasons for believing that the goal of treatment in hypertension should be to reduce mean arterial pressure to normal, not just to reduce the diastolic pressure to normal (17, 18). However, in the absence of evidence from prospective randomized trials that treatment of systolic hypertension is effective in reducing morbidity and mortality, there can be TABLE 2 STATUS OF POPULATION AT I-YEAR FOLLOW-UP VISIT
Characteristics
Number
Percentage
Subjects Follow-up at American Heart Association rescreening site Follow-up direct or by local M.D. Information on salt Use salt at table Information on drug treatment On treatment for hypertension
160
100 67 33
132
100
136
100
72 16
574
NUGENT
AND
GERLACH
TABLE 3 DEGREE OF CONTROL AT 1 YEAR OF PATIENTS WITH DIASTOLIC PRESSURESr 104 mm Hg AT THE TIME OF THE INITIAL SCREENING
Control at 1 year (% of subjects)
Criteria for control (mm Hg)
Good Fair Poor
Very poor
Systolic
Diastolic
Systolic
Diastolic
<140 140- 159 160- 179 2180
40 90-94 95-104 2105
0 42 33 25
37 18 16 29
no generally accepted level of systolic pressure which, when observed, should lead to treatment with antihypertensive drugs. Programs for Controlling Hypertension Community programs in this country and in Canada for controlling hypertension (2, 9, 15, 19, 26, 27, 29) usually share certain characteristics. Management of treatment has not been centralized, but has usually been the responsibility of numerous physicians, either in private practice or in university hospital clinics, who followed no single treatment protocol. Langfeld (19) examined hypertension control in a community and concluded that hypertension frequently was unrecognized or untreated and even that when treatment was initiated, it frequently was ineffective or was discontinued by the patient or the physician. A number of large programs have been successful in controlling hypertension with drugs in a high proportion of subjects (3, 10, 12,13, 15,23,28), but characteristically these are not community programs. They have usually recruited subjects from work sites, conducted treatment at the work sites, used simple treatment protocols, and employed mainly personnel other than physicians for managing patients. The subjects in these work site programs differ from those recruited in community programs in that they are all healthy, competent, and employed. The greater success achieved in work site in contrast to community programs may be attributable to differences in the populations rather than differences in the management programs. Part of the Hypertension Detection and Follow-up Program (15) has centralized management features similar to those outlined above and has been relatively successful in controlling hypertension in a large group of patients, many of whom were recruited from the community. Present Program We examined what a community could do in managing hypertension with its existing facilities for medical care. Our participation was limited to identifying the patients, providing them with some information on hypertension, referring them to their physicians for care, and examining the results after 1 year. It was encouraging that the program resulted in an increase in the proportion of subjects receiving drug treatment for hypertension from an initial level of about one-third to a l-year level of three-quarters. In the 73% of subjects for whom
COMMUNITY
HYPERTENSION
575
CONTROL
follow-up blood pressures were available, the mean decreases in systolic and diastolic pressure (24.5 and 10.7 mm Hg, respectively) were substantial. Initially, 70% of the subjects had systolic hypertension and 64% diastolic hypertension (definite or moderate) while at 1 year only 40% had systolic hypertension and 24 had diastolic hypertension. In terms of community resources, the program was not expensive. On the other hand, it is discouraging that we do not have information on 27% of the hypertensive subjects lost to follow-up within the first year. This low proportion of patients available for follow-up examination is not peculiar to this study (29). Although an increased proportion of hypertensive subjects were on antihypertensive drugs at the time of the follow-up visit, not all were on the drugs and not all those on the drugs were well controlled. Almost half of the patients with definite diastolic hypertension (105 mm Hg or more) in the initial screening for whom follow-up information was available had very poor (105 mm Hg or more in 29%) or poor control (955 104 mm Hg in 16%). Even though there is considerable evidence (a) that excessive sodium intake is a major factor responsible for the current high incidence of hypertension in developed countries (22) and (b) that even moderate salt restriction is of some value in decreasing elevated blood pressure (16), 72% of the subjects were using salt at the table at the time of the l-year follow-up examination. While mean systolic and diastolic pressures decreased significantly during the year, part of this improvement could have been attributable to regression toward the mean. We cannot claim that we screened a representative sample of the population or that we identified the characteristics of the unscreened 86% of the adult population of Yuma. General Criteria for Hypertension
Detection
and Treatment
Programs
Sackett reported (25) a set of criteria that should be met before initiating screening programs for any disease. Briefly, (a) treatment must improve survival or function, (b) diagnosis and treatment must be adequate, (c) compliance must be adequate, and (d) the disease must be a serious burden. In the case of patients with diastolic blood pressures greater than 104 mm Hg, substantial (I), though not complete (1, 7, 8), agreement might be reached that these patients meet the first and fourth of Sackett’s criteria. From our experience and that of others (2, 9, 15, 19, 26, 27, 29) the generalization can be made that referral of patients to physicians in the community has not resulted in a high degree of control of hypertension. Deficiencies in treatment and compliance (see Sackett’s second and third criteria) may be the basis for this limited performance. To improve on these results, community programs for control of hypertension might consider expanding programs such as that tried in Yuma, developing alternative approaches to management, or adopting programs emphasizing prevention. Screening with referral to community physicians might give better results if more elements in the community were involved than in the Yuma trial. This might include an educational program on hypertension management organized by a medical society, and involvement of pharmacists in monitoring drug compliance. An alternative would be to centralize management of hypertensive patients cur-
576
NUGENT
AND
GERLACH
rently receiving care from public facilities. If successful, this could be expanded to include a larger proportion of the community but only at a substantial cost in community resources and in disturbing existing systems of medical practice. The report of the Hypertension Detection and Follow-up Program (15) should be examined to see the success that has been achieved by centralized treatment of community patients. Finally, instead of expanding medical management programs, a preventive approach should be considered. Blackburn (5) has presented an incisive analysis of the limited value of screening and treatment programs for hypercholesterolemia as a method for controlling coronary heart disease in the United States. Similar arguments could be developed for hypertension screening and referral programs and cardiovascular disease. Morbidity and mortality attributable to hypertension might be more favorably altered by decreasing sodium chloride consumption in the whole population than by increasing efforts to identify and to treat with drugs those persons with the highest pressures (5). REFERENCES 1. Alderman, M. H. High blood pressure: do we really know whom to treat and how? New Engl. J. Med. 296, 753-755 (1977). 2. Alderman, M. H., and Ores, 0. S. Treatment of hypertension at the University Medical Center. Arch. Intern. Med. 137, 1707-1710 (1977). 3. Alderman, M. H., and Schoenbaum, E. E. Detection and treatment of hypertension at the work site. New Engl. J. Med. 293, 65-68 (1975). 4. “Arizona Statistical Review,” 33rd ed. Valley National Bank of Arizona, Phoenix, 1977. 5. Blackbum, H. Progress in the epidemiology and prevention of coronary heart disease. Progr. Curdiol. 3, l-36 (1974). 6. “Build and Blood Pressure Study.” Society of Actuaries, Chicago, 1959. 7. Chasis, H. Premature screening for hypertension. New Engl. J. Med. 291, 258-259 (1974). 8. “Diuretics in the Elderly” (Editorial). Bit. Med. J. 1, 1092- 1093 (1978). 9. Engelland, A. L., Alderman, M. H., and Powell, H. B. Blood pressure control in private practice: a case report. Amer. J. Publ. Health 69, 25-29 (1979). 10. Finnerty, F. A., Jr., Shaw, L. W., and Himmelsbach, C. K. Hypertension in the inner city, II. Circulation 47, 76-78 (1973). 11. Fries, E. D. How far should blood pressure be lowered in treating hypertension? JAMA 232, 1017-1018 (1975). 12. Hames, C., Kwiatkowki, J., Heyden, S., and Tyroler, H. Hypertension intervention in a biracial community. Circulation 52 (Suppl. 2), 193 (1973). 13. Haynes, R. B., Sackett, D. L., and Gibson, E. S. Improvement of medication compliance in uncontrolled hypertension. Lancer 1, 1265- 1268 (1976). 14. “High Blood Pressure.” Amer. Heart Assoc., Dallas. 15. Hypertension Detection and Follow-up Program Group. Therapeutic control of blood pressure in the hypertension detection and follow-up program. Prev. Med. 8, 2- 13 (1979). 16. Joossens, J. V. Salt and hypertension, water hardness and cardiovascular death rate. Triangle 12, 9-16 (1973). 17. Koch-Weser, J. Correlation of pathophysiology and pharmacotherapy in primary hypertension. Amer. J. Cardiol. 32, 499-510 (1973). 18. Koch-Weser, J. The therapeutic challenge of systolic hypertension. New Engl. J. Med. 289, 481-483 (1973). 19. Langfeld, S. B. Hypertension: deficient care of the medically served. Arm. Intern. Med. 78, 19-23 (1973). 20. Morgan, T., Carney, S., and Wilson, M. Interrelationship in humans between sodium intake and hypertension. Clin. Exp. Pharmacol. Physiol. 2 (Suppl.), 127- 129 (1975). 21. Moser, M. “How you can help your doctor treat your high blood pressure.” Amer. Heart Assoc., Dallas, 1974.
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HYPERTENSION
CONTROL
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22. Nugent, C. A. Salt and essential hypertension. Ariz. Med. 34, 29-32 (1977). 23. Podell, R. N., and Gary, L. R. Hypertension and compliance: implications for the primary physician. New Engl. J. Med. 294, 1120-1121 (1976). 24. Report of the joint national committee on detection, evaluation, and treatment of high blood pressure: a comparative study. JAMA 237, 255-261 (1977). 25. Sackett, D. L. Cardiovascular diseases. Lancer 2, 1189-1191 (1974). 26. Sackett, D. L., Gibson, E. S., Taylor, D. W., Haynes, R. B., Hackett, B. C., Roberts, R. S., and Johnson, A. L. Randomized clinical trial of strategies for improving medication compliance in primary hypertension. Lancet 1, 1205- 1207 (1975). 27. Schoenberger, J. A., Stamler, J., Schekelle, R. B., and Shekelle, S. Current status of hypertension control in an industrial population. JAMA 222, 559-562 (1972). 28. Veterans Administration Cooperative Study Group on Antihypertensive Agents. Effect of treatment on morbidity and mortality. II. Results in patients with diastolic pressures averaging 90 through 114 mg Hg. JAMA 213, 1143-1152 (1970). 29. Wilbur, J. A. and Barrow, J. G. Hypertension: a community problem. Amer. J. Med. 52,653-663 (1972).
MEDICINE
9, 569-577
Hypertension
(1980)
Control:
Referral
The Role of Screening
to Community
and
Physicians
CHARLES A. NUGENT",' AND BARBARA A. GERLACH~ *Section of Endocrinology, Department of Internal Medicine, University o./’ Arizona College of Medicine, Tucson, Arizona 85724, and tAmerican Heart Association, Southern Arizona Division, Tucson, Arizona 85716 In this trial of one method to control hypertension, adults in a community were screened and those with elevated pressures were referred to their local physicians for management. On a follow-up survey 1 year later blood pressure measurements were obtained on 73% of the patients originally identified as hypertensive. In those rescreened there had been an increase in the proportion of subjects receiving drug treatment for hypertension from onethird to three-quarters. Also, systolic and diastolic pressures were significantly lower. HOWever, the degree of control of hypertension was often inadequate. Of those subjects who initially had disatolic pressures of 10.5 mm Hg or more, only 42% could be classified as having fair to good control of their pressure. Screening patients in a community and referring them to their physicians for management was shown to be a relatively ineffective method for controlling hypertension. Expanded or alternative screening and referral programs need to be developed or increased emphasis placed on prevention to improve on these results.
INTRODUCTION
The American Heart Association, Southern Arizona Division, has a simple goal: to decrease morbidity and mortality due to cardiovascular disease in Southem Arizona. In 1976 we selected control of hypertension as the most practicable method to achieve this goal. Hypertension is a major contributor to the development of cardiovascular diseases and procedures for detection, management, and follow-up seem to be available (24). Before starting a hypertension control program, a trial was undertaken to test one method. Screening was done by the Heart Association. Subjects with elevated blood pressures were told the results, were given pamphlets on the problem, and were referred to their local physicians for management. One year later those patients who had been identified as hypertensive were interviewed and screened again for hypertension. The results of the trial are reported here. POPULATION
AND METHODS
Screening was conducted over 2 days in the city of Yuma (population 30,081) (4). Using figures for the age distribution in the nonmetropolitan counties of the state, the estimate was made that 19,550 of the inhabitants of Yuma were 17 years of age or older (4). The free screening program was publicized by television, radio, and newspaper. The county medical society was told about our program. Screening was conducted by Heart Association employees and trained volunteers. All subjects sat for 2 to 5 min while completing their questionnaire before their blood pressure was ’ To whom reprint requests should be addressed at: 1501 N. Campbell Ave., Tucson, Ariz. 85724. 569 0091-7435/80/040569-09$02.00/0 Copyrisbt All d&s
@ 1!%30by Academic Press. Inc. of reproductionin any f,mn reserved.
570
NUGENT
AND
GERLACH
measured in the right arm of the seated subject. The onset of the fifth Korotkoff phase was used for estimating diastolic pressure. If the blood pressure was elevated above 159 mm Hg systolic or 94 mm Hg diastolic, they were asked to rest for lo- 15 min and a second determination was made. Subjects who were taking antihypertensive drugs, but had borderline or no elevation of their blood pressure, were not classified as having definite hypertension in this study. Subjects less than 17 years old were excluded. Screenees with final pressures exceeding 159 mm Hg systolic or 94 mm Hg diastolic were told that they had high readings and were urged to see a physician promptly. Those who could not afford private care were referred to a public health clinic where charges were adjusted to income and service was free to those eligible. Each person with hypertension was also given two information booklets on hypertension (14, 21). At the time of the screening, hypertensive subjects were also asked if they were taking antihypertensive medicine or birth control pills and if they usually added salt to their food. Subjects were also asked if they were willing to participate and only those who agreed and who signed permission for their physicians to release medical information were included. One year after the initial screening, announcements of the rescreening for those with hypertension were made over television, radio, and in the newspaper. All subjects with pressures exceeding 159 mm Hg systolic or 94 mm Hg diastolic on the initial screening were contacted by mail and telephone and asked to return. At the time of the follow-up blood pressure determinations, subjects were asked if they were taking antihypertensive medications, or birth control pills, or using salt at the table. Hypertensive subjects who did not appear for the follow-up examination were contacted by letter and phone or their physicians’ offices were telephoned in the attempt to obtain follow-up information. RESULTS
Fourteen percent of the adult population of Yuma was screened. After excluding out-of-town visitors, who were unlikely to be available for follow-up examinations, 9% of those screened were hypertensive (Table 1). Analysis of the 226 hypertensive subjects is confined to the 219 who were willing to participate in the study. This segment of the population was predominantly white and included similar numbers of men and women; 89% were more than 44 years old. Sixty-three percent of the subjects usually added salt to their food. None were taking oral contraceptives. The pressures on the initial visit are displayed in Fig. IA and are separated into four degrees of severity of hypertension in Fig. 2A. Of the 219 subjects identified as having systolic or diastolic hypertension, the systolic elevation was definite (2180 mm Hg) or moderate (160- 179 mm Hg) in 70% while diastolic elevations were definite (2 105 mm Hg) in 22% and moderate (95- 104 mm Hg) in 42% (Fig. 2A). One-third of the subjects were taking antihypertensive drugs at the time of their initial screening (Fig. 2A and Table 1). At the l-year follow-up visit, information on blood pressure was available on 160 of the hypertensive subjects (Table 2). Seventy-two percent of the subjects questioned on salt intake said they used salt at the table. Three-quarters of the subjects on whom information was available were on drug treatment for hypertension (Table 2). Again, none took oral contraceptives.
COMMUNITY
HYPERTENSION
571
CONTROL
TABLE 1 POPULATIONON INITIAL SCREENING Number Composition Out-of-town residents Normotensive subjects Borderline hypertensive subjects Hypertensive subjects Refused to participate Signed up to participate
Percentage
118 1,583 799 7 219 2,726
Characteristics Subjects Race White Black Other Sex Men Age (years) 44 45-54 5.5-64 65-74 375 Information on salt Usually add salt to food Information on drug treatment On treatment for hypertension
219 206
216 219
160 173
100 100 83 15 2 100 49 100 11 12 28 35 14 loo 63 100 34
The mean systolic/diastolic pressures of the 160 patients with follow-up data were 177.7/97.5 mm Hg on the initial visit and 153.2/86.8 mm Hg on the l-year follow-up (p < 0.001 for both systolic and diastolic pressures). The severity of hypertension and the proportion of patients treated with antihypertensive drugs are shown in Fig. 2B. At the time of the l-year follow-up, 40% of these subjects now had definite or moderate diastolic elevations. Furthermore, 86% of those with moderate or definite systolic elevations were on drug therapy for hypertension and this was true in 80% of those with elevations of diastolic pressure (Fig. 2B). Of those individuals with definite diastolic hypertension on the initial visit, at the time of the l-year visit, fair or good control of diastolic pressure was achieved in 55%, while for systolic pressure the figure was 42% (Table 3). DISCUSSION Indications
for Drug Therapy for Hypertension
The decision in this hypertension control program to refer all screenees with pressures greater than 160 systolic or 95 mm Hg diastolic to their physicians for management is arguable. Mortality rates do rise with increases in systolic and in diastolic blood pressure (6). But this is not sufficient evidence that treatment
572
NUGENT
1---‘I I I I I I 30 f I 20 -
i I I L-1
rI .--A
o--i
i I
I
’
Data on All Subjects
-7
1
-
htiil
GERLACH
I I-
I J 10
AND
’
’
’
L’ 1
40 c I---I , i
lnitiil
Data on Subiects
Diastolic
B.
for
Systolic BP in mmlig
FIG. 1. Percentage of patients as a function of the levels of systolic and diastolic blood pressure. The results in the total population of 219 subjects initially identified as hypertensive are displayed in (A). The results in the subjects for whom both initial and l-year follow-up blood pressures are available are displayed in (B). Data on the initial and final blood pressures are recorded as dashed and continuous lines, respectively.
would necessarily improve the outcome. The VA Cooperative Study convincingly demonstrated the effectiveness of drug therapy for hypertension in decreasing morbidity and mortality in men with initial diastolic pressures greater than 104 mm Hg (28). In this study it was assumed that physicians should treat all patients with diastolic pressures greater than 104 mm Hg and that most compliant patients would be able to reduce their diastolic pressure to less than 90 mm Hg. Admittedly, not all would agree with our assumptions on the indications for treatment (1, 7, 8) or the goal for therapy (11). Reduction of diastolic pressure, even though levels as low as !I0 mm Hg are not attained, is also of value in reducing morbidity (11). The National Committee on Detection, Evaluation, and Treatment of High Blood Pressure recommends that antihypertensive drug treatment for subjects
COMMUNITY
HYPERTENSION
573
CONTROL
lnitiil Visit
Svstolic
Diastolic A.
BP mmHg
180 or>
160-179
140-159
Absent cl40 r I, resow
Def. 105 or> up Visit
MOI 95-104
Bord. 90-94
Absent ~90
Systolic
0 BP mmHg
Def. l&I or>
Mod.
Bard.
160-179 140-159
Absent 440
Def.
Mod.
Bord.
Absent
105or>
95104
so-94
c9l
FIG. 2. The heights of the columns indicate the percentage of subjects with different degrees of
hypertension. Blood pressures at the time of the initial visit are shown in (A) and at the time of the first year follow-up visit in (B). The shaded areas are the percentage of subjects on drug treatment for hypertension at the time they were seen.
with diastolic pressure of 90 to 104 mm Hg should be individualized with consideration given to other risk factors (24). There are many reasons for believing that the goal of treatment in hypertension should be to reduce mean arterial pressure to normal, not just to reduce the diastolic pressure to normal (17, 18). However, in the absence of evidence from prospective randomized trials that treatment of systolic hypertension is effective in reducing morbidity and mortality, there can be TABLE 2 STATUS OF POPULATION AT I-YEAR FOLLOW-UP VISIT
Characteristics
Number
Percentage
Subjects Follow-up at American Heart Association rescreening site Follow-up direct or by local M.D. Information on salt Use salt at table Information on drug treatment On treatment for hypertension
160
100 67 33
132
100
136
100
72 16
574
NUGENT
AND
GERLACH
TABLE 3 DEGREE OF CONTROL AT 1 YEAR OF PATIENTS WITH DIASTOLIC PRESSURESr 104 mm Hg AT THE TIME OF THE INITIAL SCREENING
Control at 1 year (% of subjects)
Criteria for control (mm Hg)
Good Fair Poor
Very poor
Systolic
Diastolic
Systolic
Diastolic
<140 140- 159 160- 179 2180
40 90-94 95-104 2105
0 42 33 25
37 18 16 29
no generally accepted level of systolic pressure which, when observed, should lead to treatment with antihypertensive drugs. Programs for Controlling Hypertension Community programs in this country and in Canada for controlling hypertension (2, 9, 15, 19, 26, 27, 29) usually share certain characteristics. Management of treatment has not been centralized, but has usually been the responsibility of numerous physicians, either in private practice or in university hospital clinics, who followed no single treatment protocol. Langfeld (19) examined hypertension control in a community and concluded that hypertension frequently was unrecognized or untreated and even that when treatment was initiated, it frequently was ineffective or was discontinued by the patient or the physician. A number of large programs have been successful in controlling hypertension with drugs in a high proportion of subjects (3, 10, 12,13, 15,23,28), but characteristically these are not community programs. They have usually recruited subjects from work sites, conducted treatment at the work sites, used simple treatment protocols, and employed mainly personnel other than physicians for managing patients. The subjects in these work site programs differ from those recruited in community programs in that they are all healthy, competent, and employed. The greater success achieved in work site in contrast to community programs may be attributable to differences in the populations rather than differences in the management programs. Part of the Hypertension Detection and Follow-up Program (15) has centralized management features similar to those outlined above and has been relatively successful in controlling hypertension in a large group of patients, many of whom were recruited from the community. Present Program We examined what a community could do in managing hypertension with its existing facilities for medical care. Our participation was limited to identifying the patients, providing them with some information on hypertension, referring them to their physicians for care, and examining the results after 1 year. It was encouraging that the program resulted in an increase in the proportion of subjects receiving drug treatment for hypertension from an initial level of about one-third to a l-year level of three-quarters. In the 73% of subjects for whom
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follow-up blood pressures were available, the mean decreases in systolic and diastolic pressure (24.5 and 10.7 mm Hg, respectively) were substantial. Initially, 70% of the subjects had systolic hypertension and 64% diastolic hypertension (definite or moderate) while at 1 year only 40% had systolic hypertension and 24 had diastolic hypertension. In terms of community resources, the program was not expensive. On the other hand, it is discouraging that we do not have information on 27% of the hypertensive subjects lost to follow-up within the first year. This low proportion of patients available for follow-up examination is not peculiar to this study (29). Although an increased proportion of hypertensive subjects were on antihypertensive drugs at the time of the follow-up visit, not all were on the drugs and not all those on the drugs were well controlled. Almost half of the patients with definite diastolic hypertension (105 mm Hg or more) in the initial screening for whom follow-up information was available had very poor (105 mm Hg or more in 29%) or poor control (955 104 mm Hg in 16%). Even though there is considerable evidence (a) that excessive sodium intake is a major factor responsible for the current high incidence of hypertension in developed countries (22) and (b) that even moderate salt restriction is of some value in decreasing elevated blood pressure (16), 72% of the subjects were using salt at the table at the time of the l-year follow-up examination. While mean systolic and diastolic pressures decreased significantly during the year, part of this improvement could have been attributable to regression toward the mean. We cannot claim that we screened a representative sample of the population or that we identified the characteristics of the unscreened 86% of the adult population of Yuma. General Criteria for Hypertension
Detection
and Treatment
Programs
Sackett reported (25) a set of criteria that should be met before initiating screening programs for any disease. Briefly, (a) treatment must improve survival or function, (b) diagnosis and treatment must be adequate, (c) compliance must be adequate, and (d) the disease must be a serious burden. In the case of patients with diastolic blood pressures greater than 104 mm Hg, substantial (I), though not complete (1, 7, 8), agreement might be reached that these patients meet the first and fourth of Sackett’s criteria. From our experience and that of others (2, 9, 15, 19, 26, 27, 29) the generalization can be made that referral of patients to physicians in the community has not resulted in a high degree of control of hypertension. Deficiencies in treatment and compliance (see Sackett’s second and third criteria) may be the basis for this limited performance. To improve on these results, community programs for control of hypertension might consider expanding programs such as that tried in Yuma, developing alternative approaches to management, or adopting programs emphasizing prevention. Screening with referral to community physicians might give better results if more elements in the community were involved than in the Yuma trial. This might include an educational program on hypertension management organized by a medical society, and involvement of pharmacists in monitoring drug compliance. An alternative would be to centralize management of hypertensive patients cur-
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rently receiving care from public facilities. If successful, this could be expanded to include a larger proportion of the community but only at a substantial cost in community resources and in disturbing existing systems of medical practice. The report of the Hypertension Detection and Follow-up Program (15) should be examined to see the success that has been achieved by centralized treatment of community patients. Finally, instead of expanding medical management programs, a preventive approach should be considered. Blackburn (5) has presented an incisive analysis of the limited value of screening and treatment programs for hypercholesterolemia as a method for controlling coronary heart disease in the United States. Similar arguments could be developed for hypertension screening and referral programs and cardiovascular disease. Morbidity and mortality attributable to hypertension might be more favorably altered by decreasing sodium chloride consumption in the whole population than by increasing efforts to identify and to treat with drugs those persons with the highest pressures (5). REFERENCES 1. Alderman, M. H. High blood pressure: do we really know whom to treat and how? New Engl. J. Med. 296, 753-755 (1977). 2. Alderman, M. H., and Ores, 0. S. Treatment of hypertension at the University Medical Center. Arch. Intern. Med. 137, 1707-1710 (1977). 3. Alderman, M. H., and Schoenbaum, E. E. Detection and treatment of hypertension at the work site. New Engl. J. Med. 293, 65-68 (1975). 4. “Arizona Statistical Review,” 33rd ed. Valley National Bank of Arizona, Phoenix, 1977. 5. Blackbum, H. Progress in the epidemiology and prevention of coronary heart disease. Progr. Curdiol. 3, l-36 (1974). 6. “Build and Blood Pressure Study.” Society of Actuaries, Chicago, 1959. 7. Chasis, H. Premature screening for hypertension. New Engl. J. Med. 291, 258-259 (1974). 8. “Diuretics in the Elderly” (Editorial). Bit. Med. J. 1, 1092- 1093 (1978). 9. Engelland, A. L., Alderman, M. H., and Powell, H. B. Blood pressure control in private practice: a case report. Amer. J. Publ. Health 69, 25-29 (1979). 10. Finnerty, F. A., Jr., Shaw, L. W., and Himmelsbach, C. K. Hypertension in the inner city, II. Circulation 47, 76-78 (1973). 11. Fries, E. D. How far should blood pressure be lowered in treating hypertension? JAMA 232, 1017-1018 (1975). 12. Hames, C., Kwiatkowki, J., Heyden, S., and Tyroler, H. Hypertension intervention in a biracial community. Circulation 52 (Suppl. 2), 193 (1973). 13. Haynes, R. B., Sackett, D. L., and Gibson, E. S. Improvement of medication compliance in uncontrolled hypertension. Lancer 1, 1265- 1268 (1976). 14. “High Blood Pressure.” Amer. Heart Assoc., Dallas. 15. Hypertension Detection and Follow-up Program Group. Therapeutic control of blood pressure in the hypertension detection and follow-up program. Prev. Med. 8, 2- 13 (1979). 16. Joossens, J. V. Salt and hypertension, water hardness and cardiovascular death rate. Triangle 12, 9-16 (1973). 17. Koch-Weser, J. Correlation of pathophysiology and pharmacotherapy in primary hypertension. Amer. J. Cardiol. 32, 499-510 (1973). 18. Koch-Weser, J. The therapeutic challenge of systolic hypertension. New Engl. J. Med. 289, 481-483 (1973). 19. Langfeld, S. B. Hypertension: deficient care of the medically served. Arm. Intern. Med. 78, 19-23 (1973). 20. Morgan, T., Carney, S., and Wilson, M. Interrelationship in humans between sodium intake and hypertension. Clin. Exp. Pharmacol. Physiol. 2 (Suppl.), 127- 129 (1975). 21. Moser, M. “How you can help your doctor treat your high blood pressure.” Amer. Heart Assoc., Dallas, 1974.
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22. Nugent, C. A. Salt and essential hypertension. Ariz. Med. 34, 29-32 (1977). 23. Podell, R. N., and Gary, L. R. Hypertension and compliance: implications for the primary physician. New Engl. J. Med. 294, 1120-1121 (1976). 24. Report of the joint national committee on detection, evaluation, and treatment of high blood pressure: a comparative study. JAMA 237, 255-261 (1977). 25. Sackett, D. L. Cardiovascular diseases. Lancer 2, 1189-1191 (1974). 26. Sackett, D. L., Gibson, E. S., Taylor, D. W., Haynes, R. B., Hackett, B. C., Roberts, R. S., and Johnson, A. L. Randomized clinical trial of strategies for improving medication compliance in primary hypertension. Lancet 1, 1205- 1207 (1975). 27. Schoenberger, J. A., Stamler, J., Schekelle, R. B., and Shekelle, S. Current status of hypertension control in an industrial population. JAMA 222, 559-562 (1972). 28. Veterans Administration Cooperative Study Group on Antihypertensive Agents. Effect of treatment on morbidity and mortality. II. Results in patients with diastolic pressures averaging 90 through 114 mg Hg. JAMA 213, 1143-1152 (1970). 29. Wilbur, J. A. and Barrow, J. G. Hypertension: a community problem. Amer. J. Med. 52,653-663 (1972).