INCREASED RISK FOR TYPE-I (INSULIN-DEPENDENT) DIABETES IN RELATIVES OF PATIENTS WITH ALOPECIA-AREATA (AA)

The prevalence of various chronic diseases was compared in 517 individ uals with alopecia areata, and 2,969 of their first degree relatives. As previous reports have suggested an increased incidence of diabetes in relatives of patients with alopecia areata, special attention was g iven to the prevalence of Type 1 and Type 2 diabetes in the patients a nd in their relatives. Several immunologic diseases were increased in alopecia probands and relatives. Thyroid disease, vitiligo, Addison di sease, and pernicious anemia were more prevalent in probands and in th eir relatives than in the general population. Specifically, a high rat e of thyroid disease was found in probands (14.7%) and in their first degree relatives (4.2%). Only one proband had Type I diabetes, yet the re were 14 sibs with Type 1 diabetes. Thus, Type 1 diabetes was signif icantly more prevalent in the sibs (1.2%) than in either the probands with alopecia (0.2%), or the general population (0.12-0.25%) (P < 0.05 )). In contrast, Type 2 diabetes was not more common in probands or in sibs than in the general population. These data suggest that alopecia areata protects against Type 1 diabetes in predisposed individuals. T he high rate of thyroid disease suggests that screening probands and f irst degree relatives for thyroid disease should be considered. (C) 19 94 Wiley-Liss, Inc.