Pemphigus variant associated with penicillin use: a case-cohort study of 363 patients from Israel.
OBJECTIVE
To determine whether medication use is associated with the development of a pemphigus variant.


METHODS
Population-based case-cohort study.


METHODS
Health maintenance organization in Israel.


METHODS
All incident pemphigus variant cases diagnosed from January 1, 1997, through December 31, 2001, among 1.5 million members were identified. A cohort of 150,000 was randomly selected from the health maintenance organization population as the control group. Data on case patients and control subjects, including all medication purchased during the 6 months before the diagnosis, were obtained using the health maintenance organization's central database.


RESULTS
We identified a total of 363 case patients diagnosed as having pemphigus during the 5-year study (6,961,853 person-years of follow-up). The mean age at diagnosis was 49.8 (SD, 22.7) years, and 53% of the cases were women. Results of a multivariate analysis showed that increased risk for pemphigus was associated with purchasing penicillin during the 6 months before the diagnosis (odds ratio, 2.03; 95% confidence interval, 1.56-2.64). Compared with individuals with no penicillin purchases, we calculated increased risks of 1.84 (95% CI, 1.36-2.49) and 3.02 (95% CI, 1.41-6.49) in those with 1 and 3 or more purchases, respectively. None of the other examined medications, including cephalosporins, angiotensin-converting enzyme inhibitors, dipyrone, anticonvulsants, and nonsteroidal anti-inflammatory drugs, showed similar risks.


CONCLUSIONS
To our knowledge, the present research is one of the largest published epidemiological studies on pemphigus variant. The use of computerized medical and administrative databases allowed the detection of case patients in the community, resulting in a higher calculated incidence rate than previously reported. The findings suggest a relationship between the use of penicillin and pemphigus variant. Further studies to assess the nature of this statistical association are warranted.
Heymann
Anthony D
AD
Medical Division, Maccabi Healthcare Services, and Sackler Faculty of Medicine, Tel Aviv University, Israel. Heymann_t@mac.org.il
Chodick
Gabriel
G
Kramer
Eyal
E
Green
Manfred
M
Shalev
Varda
V
D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D016208:Databases, Factual; D005260:Female; D006279:Health Maintenance Organizations; D006801:Humans; D015994:Incidence; D007557:Israel / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010392:Pemphigus / Q000139:chemically induced / Q000453:epidemiology* / Q000473:pathology; D010406:Penicillins / Q000009:adverse effects*; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D018570:Risk Assessment
D010406:Penicillins