Autoimmune diseases in asthma

Background: Previous research has suggested an inverse relationship between T-helper 2-related atopic disorders, such as asthma, and T-helper 1-related autoimmune diseases. One controversial hypothesis postulates that asthma provides a protective effect for the development of autoimmune-related disorders. Objective: To assess the rate of newly diagnosed. autoimmune disorders in a large cohort of young adults. Design: Using cross-sectional data from the Israeli Defense Force database, the authors analyzed the prevalence of auto immune disorders in asthmatic and nonasthmatic military personnel between 1980 and 2003. A follow-up study traced newly diagnosed auto-immune disorders among asthmatic and nonasthmatic individuals from the time of enrollment in military service until discharge (22 and 36 months for women and men, respectively). Setting: General community Patients: 307 367 male and 181 474 female soldiers in compulsory military service who were between 18 and 21 years of age. Measurements: Cases of type 1 diabetes mellitus, vasculitis, immune thrombocytopenic purpura, inflammatory bowel disease, rheumatoid arthritis, and the antiphospholipid syndrome. Results: Of 488 841 participants at enrollment, significantly more women than men had autoimmune disorders. Compared with asthmatic women, nonasthmatic women had a significantly higher prevalence of all autoimmune disorders except for the antiphospholipid syndrome. Type 1 diabetes mellitus, vasculitis, and rheumatoid arthritis were less prevalent in men with asthma than in those without. During the follow-up period, vasculitis and rheumatoid arthritis were more frequently diagnosed in nonasthmatic persons of both sexes. There was a significantly higher incidence of immune thrombocytopenic purpura, inflammatory bowel disease, and the anti phospholipid syndrome in nonasthmatic women and a statistically significantly higher incidence of type 1 diabetes mellitus in nonasthmatic men. Limitations: The study was limited to a population of young military recruits; therefore, its findings are not necessarily applicable to the general population. Because of the noninterventional nature of the study, it describes associations but cannot prove causality. Conclusions: Asthma status may affect the prevalence of. major autoimmune disorders. Preexisting asthma seems to protect against the development of autoimmune disorders to varying degrees in men and women.