Disease outcome in workers with occupational skin disease

Journal of the American Academy of Dermatology Volume 30, Number 4

cluster at the cleft edge of the cleft lip suggests that cleft lip formation precedes the arrival of dermal melanocytes. Thus the cleft lip itself might interfere with migration of dermal me1anocytes into the epidermis, which leads to dermal melanocytosis. Inoue et al. 2 observed alterations in cleft lip mongolian spots similar to those found in naturally regressing mongolian spots, that is, a thin, irregular extracellular melanocyte sheath and the appearance of vacuoles in the cytoplasm of dermal melanocytes and me1anophages. Electron microscopy in our patients showed no evidence of degenerative changes suggesting fading of the mongolian spots.

Nethercott and Holness 2. Inoue S, Kikuchi I, Ono T. Dermal melanocytosis associated with cleft lip. Arch DermatoI1982;118:443-4. 3. Kurata S, Ohara Y, Itami S, et al. Mongolian spots associated with cleft lip. Br J Plast Reconstr 1989;42:625-7. 4. Johnston MC, Hassell JR, Brown KS. The embryology of cleft lip and cleft palate. Clin Plast Surg 1975;2:195-203. 5. Johnston MC, Sulik KK. Some abnormal patterns of development in the craniofacial region. Birth Defects 1979;15:23-42. 6. Noden OM. The migration and cytodifferentiation of cranial neural crest ceUs. In: Pratt RM, Christiansen RL, eds. Current research trends in prenatal craniofacial development. New York: Elsevier/North-Holland, 1980:3-25. 7. Slavkin He. Craniofacial morphogenesis. In: Developmental craniofacial biology. Philadelphia: Lea & Febiger, 1979:235-97.

REFERENCES I. Mori T, Onizuka T, Akagawa T, et al. Cleft lip nevus. Jpn J PlaSl Reconstr Surg 1975;18:526-7.

Disease outcome in workers with occupational skin disease James R. Nethercott, MD,a and D. Linn Holness, MDb Baltimore, Maryland, and

Toronto, Ontario, Canada Background: Occupational contact dermatitis (OeD) contributes significantly to the burden of occupational disease, but there is little known about prognostic factors. Objective: The study was designed to determine the health status of workers with OCD at least 2 years after diagnosis and to identify risk factors related to prognosis. Methods: A questionnaire study was conducted of workers with a diagnosis of work-related skin disease. Results: Of the 201 workers with OeD, 76% noted improvement and 40% reported that they were currently free of any eruption. Approximately one third noted that their skin disease interfered with household, work, or recreational activities. The key prognostic factor appeared to be sex because women reported a better outcome. Diagnosis and atopic status tended to be related to some outcomes, whereas age was not. Conclusion: Examination of other possible factors, some of which may be associated with sex, that might affect outcome should be undertaken to gain a better understanding of possible management strategies. A retrospective study has methodologic limitations and a prospective intervention trial should yield more information. (J AM ACAD DERMATOL 1994;30:569-74.)

From the Department of Environmental Health Sciences, School of Hygiene and PublicHealth, The Johns Hopkins University, Baltimore"; and the Department of Occupational and Environmental Health, St. Michael's Hospital, University of Toronto," Supported by grant 229/R by the Ontario Ministry of Labour. Accepted for publication Oct. 9, 1993.

Reprintrequests: D. Linn Holness, MD, Dept.of Occupational & Environmental Health, St. Michael's Hospital, 30 Bond St., Toronto, Ontario,Canada M5B IW8. Copyright © 1994 by the American Academy of Dermatology, Inc. 0190-9622/94 $3.00 + 0 16/1/52042

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Journal of the American Academy of Dermatology April 1994

570 Nethercott and Holness Table I. Characteristics and outcome by age

I

<35 yr 79)

=

35-55 yr (11=97)

>55 yr (11=25)

P Value*

39

28

16

0.061

49 11

45 0

52 0

0.784 0.001

92 5 24 4

o

84 6 18 8 8

92 0 16 8 0

0.157 0.447 0.488 0.464 0.011

42 41

18 24

20 12

0.001 0.006

39 28 24 32 84

34 30 21 40 78

26 30 17 44 60

0.488 0.962 0.750 0.385 0.046

68 20 9 3

60 18 19 4

56 12 24 8

(n

Sex (% female) Diagnosis (%) Allergic contact dermatitis Atopic dermatitis Location of eruption (%) Hands Feet Arms Face General Atopic status (%) Personal history of atopy Family history of atopy Current status (%) Skin problem interferes with (%) Work Home activities Recreational activities Skin eruption currently (%) Eruption improved since assessed (%) Eruption currenLly (%) Nil Mild Moderate Severe

0.330

*Value of p calcula ted from chi-sq ua re a nalysis.

Occupational contact dermatitis (OeD) constitutes a significant portion of occupational illness, accounts for chronic morbidity in some of those affected, and contributes a significant proportion of paid workers' compensation claims.' The problem of persistence of the skin disease, particularly hand dermatitis, is a vexing one. Although there is clear understanding of the clinical features and mechanism of acute allergic and irritant contact dermatitis, and normally avoidance of exposure in these instances leads to resolution ofthe problem, in the case of chronic dermatitis, whether allergic or irritant, the outcome is less predictable. Studies of prognosis in different groups with contact dermatitis report differing disease outcomes.v" Hogan et al. 16 have recently reviewed the prognosis of contact dermatitis. Although there is information concerning the possible risk factors in the development of contact dermatitis, there is little consistent information that provides insight about risk factors for various outcomes. Thus chronic occupational skin disease is a significant problem for which there is little information to assist the clinician or the compensation

authorities in determining whether the chronic state will persist. The objectives of the study were to determine the present state of health of workers with OCD at least 2 years after diagnosis and to determine which risk factors, if any, are associated with differences in disease outcome. MATERIAL AND METHODS

From a computerized database that contains the records of all patients patch tested between 1980 and 1988 , those workers who were seen between 1980 and 1986 and had a diagnosis of work-relatedcontact dermatitis wereidentified. A letter outlining the purposeof the study and seekingtheir participation was sent to each of these workers. Several weeks later the workers were called. If no response was obtained, other persons identified on the clinic registration sheet (relative, family physician) were contacted to try to locate the worker. When the worker was contacted, any questions they had about the study wereansweredand their consentto completethe questionnairewas obtained verbally. The caller who was unaware of all information about the worker, then administered the questionnaire.

Journal of the American Academyof Dermatology Volume 30, Number 4

Nethercott and Holness 571

Table II. Characteristics and outcome by sex Age at initial assessment (yr) Diagnosis (%) Allergic contact dermatitis Atopic dermatitis Location of eruption (%) Hands Feet Arms Face General Atopic status (%) Personal history of atopy Family history of atopy Current status (%) Skin problem interferes with: Work Home activities Recreational activities Eruption currently (%) Eruption improved since assessed (%) Eruption currently (%)

Male (n = 139)

Female (n = 62)

P Value'

40.8 ± 13.1

34.9 ± 12.1

0.003

41

63 6

0.004 0.366

4

88 5 5

87 2 13 10 2

23 25

38 39

0.035 0.035

33

40 33 17 24 87

0.333 0.552 0.348 0.010 0.040

76 13

0.072

6 23

28 24 43 74

Nil

57

Mild Moderate Severe

20 19

4

0.779

0.143 0.097

0.217 0.252

8 3

*Value of p calculated from chi-square analysis.

The resultswere coded and a data set created. This data set was merged with our main patch test data set to provide information from the worker's assessment and his or her patch test results. The analysis was carried out with the Statistical Analysis System (SAS)P Comparisons between binary variables used chi-square analysis. Comparisons between continuous variables were conducted with t tests. The effects of possibleconfoundingvariables were accounted for in logistic regression analyses. Odds ratios (ORs) were calculated from the logisticregression results. A p value of 0.05 was considered to be statistically significant. RESULTS Three hundred fifty-one workers with a diagnosis of work-related skin disease who were seen between 1980 and 1986 were identified as eligible for the study. Two hundred forty-seven were successfully traced. Of these, 12 were eliminated from the possible study population including two who had died, five who had moved out of North America, one who could not speak English, and four who had no telephones. Five refused to participate. Two hundred thirty (68%) of the 339 possible workers completed

the questionnaire, of whom 201 had either allergic contact dermatitis (ACD) or irritant contact dermatitis (ICD). The responders and nonresponders were compared to determine whether there were any differences between them. The nonresponders had been seen earlier (p = 0.001), were on average 3 years younger (p = 0.028), and had a higher prevalence of ACD (60%vs 48%,p = 0.044) than the responders. There were no differences in their patch test responses. The 201 workers were assessed on average 4 years after diagnosis. The current mean age of the workers assessed was 43.2 years (standard deviation 13). Ten (5%) were older than 65 years of age at the time of the follow-up assessment. Thirty-one percent were women. Forty-eight percent had a diagnosis of ACD, 52% had lCD, 5% had atopic dermatitis, and 2% had psoriasis. Twenty-eight percent and 29%, had a past or family history, respectively, of atopic disease (allergy, hay fever, asthma, or eczema). Currently, 63% had no eruption, 18% reported their eruption to be mild, 15% to be moderate, and

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Journal of the American Academy of Dermatology April 1994

Nethercott and Holness

Table III. Characteristics and outcome by diagnosis of allergic contact dermatitis

I

Non-ACD (11 = lOS)

Age at initial assessment (yr) Sex (% female) Diagnosis (%) Atopic dermatitis Location of eruption (%) Hands Feet Arms Face Generalized Atopic status (%) Personal history of atopy Family history of atopy Current status (%) Skin problem interferes with: Work Home activities Recreational activities Eruption currently (%) Eruption improved since assessed (%) Eruption currently (%) Nil Mild Moderate Severe

38.9 ±a 12.7 22

I

ACD(n= 96)

p Value·

39.1 ± 13.4 41

0.910 0.004

8

0.024

3

86 5 19 7 5

0.503 0.884 0.696 0.650 0.394

28 27

27 31

0.866 0.528

37 32 24 45 77

33 27 19 29 79

0.582 0.523 0.424 0.022 0.729

55 25 17 3

71 10 14 5

90 5 21 6

0.032

·Value of p calculated from chi-square analysis.

4% to be severe. Seventy-eight percent noted that their skin was better than it was at the time of their initial presentation to the clinic, 17% thought it was unchanged, and 5% reported it to be worse. Thirtyfive percent noticed their skin eruption had interfered with the performance of their work, 30%stated it had interfered with household activities, and 22% with recreational activities. Age tended to be related to the distribution of men and women in the group, in that a decreasing proportion of the group was women in the older age categories (Table I). The younger workers had a higher incidence of atopic dermatitis and atopy. Workers between 35 and 55 years of age had a higher prevalence of generalized dermatitis. Those in the older age category were less likely to note that their eruption was improved. A comparison of men and women revealed several differences (Table II). Women were younger and were more likely to have ACD. The women reported an increased prevalence of a family or personal history of atopy. Women were less likely to report a current eruption and more likely to have noticed improvement.

Several differences were found between those with and without ACD (Table III). Those with ACD were more often women and were less likely to have atopic dermatitis. More workers with ACD reported that they were presently free of dermatitis or that it was mild. When the variables of personal and family history of atopic status were examined separately, the results were similar, so these two variables were grouped for the analysis. Those with a personal or family history of atopy were younger and were more likely to be women and to have atopic dermatitis (Table IV). There were no associations with outcome. To control for the possible confounding effects of the various risk factors, logistic regression analysis was carried out. The results for the presence of CUfrent eruption at the time of follow-up and improvement are presented in Table V. The main explanatory variable for both outcomes was gender, with women having a better result. Workers with ACD were less likely to have a current eruption, whereas those with an atopic history tended to be more likely. Neither of these factors was related to noting

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Nethercott and Holness 573

Table IV. Characteristics and outcome by history of atopy

Age at initial assessment (yr) Sex (% female) Diagnosis (%) Allergic contact dermatitis Atopicdermatitis Location of eruption (%) Hands Feet Arms Face General Current status (%) Skin problem interferes with: Work Home activities Recreational activities Eruption currently (%) Eruption improved since assessed (%) Eruption currently (%)

No atopy (n = 118)

Atopy{n = 83)

P Value·

41.9 ± 12.7

23

34.8 ± 12.4 42

0.001 0.004

46 0

51 8

0.499 0.001

85 5

93 5 16 6 1

0.084 0.932 0.207 0.830 0.091

37 32 26 41 77

0.655 0.605 0.219 0.369 0.773

59 25

0.079

23 7 6 34

28 19 35 79

Nil

65

Mild Moderate Severe

13

11 5

19

3

·Value of p calculated from chi-square analysis.

Table V. Results of logistic regression analysis Emption lessened

Current eruption Factor

Odds ratio

Age Sex (female) Historyof atopy Allergic contact dermatitis

1.01 0.45 1.33 0.55

improvement in their skin condition. In this analysis age was not related to either outcome. DISCUSSION

The workers who participated in the study were generally similar to the overall study population . Those who were not seen tended to have been seen earlier or were younger, both factors that led to increased difficulty in tracing these persons. With respect to the overall outcome it is notable that 37% of this group still had ongoing problems with their skin at the time of follow-up. Several studies have reported the outcome of contact dermatitis in various groups. Sixty-nine percent of workers with ICD2 and 77% of workers with industrial dermatitis- were

I

p Value

Odds ratio

0.237 0.028 0.082 0.055

0.98 2.27 0.82 1.02

I

pValue

0.127 0.066 0.283 0.958

reported to have continuing problems. Results of follow-up studies of persons with positive patch test responses to specific agents revealed that between 33%6 and 75%15 with a positive response to nickel, 44% with rubber sensitivity.'' and 71 % who were dichromate positive 15 had continuing dermatitis. Continuing problems with dermatitis at follow-up were also reported in 75%10 and 79%9 of hospital workers with occupational dermatitis, and 40% of workers with dermatitis related to oils." Of our group 78% reported improvement in their skin disease. This is similar to the 67% of persons with dermatitis and a positive response to nickel. 14 Periodic or permanent problems were reported in 44% of hospital workers with occupationally related dermatitis.f

574

Nethercott and Holness

More than one third of our patients reported that their dermatitis interfered with work activities. Approximately 30% noted that it interfered with household activities. These results are similar to those of Meding and Swanbeck!' who studied persons with hand eczema and reported 44% noted interference with work activities and 32% who had had to change their daily activities. Jowett and Ryan l 8 found that, in general, 38% of patients with eczema noticed interference in their social life. Although age appeared to be associated with a lack of improvement on simple analysis, this relation was not confirmed on logistic regression analysis when other confounders were included in the model. Few others have examined the effect of age. Previous studies by Johnson and Wilson 4 and Burrows? noted no effect of age on outcome. There has not been much study of the effect of sex on outcome. This was the main predictor associated with outcome in our group; men fared worse than women. Hellier also noted that men tended to do worse than women (80% recurrence in men, 67% in womenj.? In contrast, Fregert 10 noted that there was no difference in outcome between male and female workers with dermatitis (21 % of the women and 28% of the men were clear of disease). The difference in outcome between men and women may reflect some biologic or behavioral differences. These include compliance with treatment or degree to which the person modified activities, such as use of cutaneous protection or avoidance of other irritants that might contribute to the dermatitis. Those with ACD reported fewer current problems than those with, ICD. This agrees with the findings of several others. Hellier s concluded that those with ACD did better, with 32% clear of dermatitis at follow-up compared with only 14% with ICD. Morgan and Davies 12 noted that 65% of persons with ACD were clear compared with only 33% of those who did not have ACD. In contrast, Fregert!" found that those with ACD tended to do worse; only 24% of men and 26% of women with ACD were completely clear at follow-up compared with 31% and 26%, respectively, of those with ICD. A significant proportion of workers with contact dermatitis continue to have active disease that causes interference in their life despite treatment and other therapeutic interventions. The outcome does not appear to have changed significantly in the past 30 years despite improvements in methods of

Journal of the American Academy of Dermatology April 1994

diagnosis and treatment of contact dermatitis. Few specificfactors have so far been identifiedthat affect outcome. This suggests that other factors such as methods of contactant avoidance, patient understanding of the disorder, 19 aggressivereturn-to-work programs, and attention to nonoccupational aggravating factors may be important to outcome. These have, by and large, not been as closelyexamined as they should be and probably bear further investigation in carefully controlled clinical studies if improvement in the prognosis in such patients is to be achieved. REFERENCES 1. Mathias CGT. Prevention of occupational contact dermatitis. JAM ACAD DERMATOL 1990;23:742-8. 2. Keczkes K, BhateSM, WyattEH. The outcome of primary irritant contact dermatitis. Br J DermatoI1983;109:665-8. 3. Breit R, Turk RBM. The medical and social fate of the dichromate anergic patient. Br J Dermatol 1976;94:349-51. 4. Johnson ML, Wilson HTH. Oil dermatitis: an enquiry into its prognosis. Br J Ind Med 1971;28:122-5. 5. Hellier FF. The prognosis in industrial dermatitis. Br Med J 1958;1:196-8. 6. Rhodes EL, Warner J. Contact eczema: a follow-up study. Br J Dermatol 1966;78:640-4. 7. Harrison PV. A postal survey of patients with nickel and chromate dermatitis. Contact Dermatitis 1979;5:229-32. 8. Lammintausta K, Kalimo K, Aantaa S. Course of hand dermatitis in hospital workers. Contact Dermatitis 1982;8:327-32. 9. Burrows D. Prognosis in industrial dermatitis. Br J DermatoI1972;87:145-8. 10. Fregert S. Occupational dermatitis in a 100year material. Contact Dermatitis 1975;1:96-107. 11. Meding B, Swanbeck G. Consequences of having hand eczema. Contact Dermatitis 1990;23:6-14. 12. Morgan J K, Davies JHT. The influence of attitudes in the rehabilitation of industrial cases. Br J DermatoI1956;68:4151. 13. Williamson KS. A prognostic study of occupational dermatitis cases in a chemical works. Br J Ind Med 1967; 24:103-13. 14. Christensen OB. Prognosis in nickel allergy and hand eczema. Contact Dermatitis 1982;8:7-15. 15. Dooms-Goossens A, Ceuterick A, Vanmaele N, et al. Follow-up study of patients with contact dermatitis caused by chromates, nickel, and cobalt. Dermatologica 1980; 160:249-60. 16. Hogan OJ, Dannaker CJ, Maibach HI. The prognosis of contact dermatitis. J AM ACAD DERMATOL 1990;23:300-7. 17. SAS Institute Inc. SAS user's guide: statistics. Cary, NC: SAS Institute, 1985. 18. Jowett S, Ryan T. Skin disease and handicap: an analysis oftheimpactofskin conditions.Soc Sci Med 1985;20:425-9. 19. Holness DL, Nethercott JR. Is a worker's understanding of their diagnosis an important determinant of outcome in occupational contact dermatitis? Contact Dermatitis 1991; 25:296-301.