A case-control study of asthma and ovarian cancer.

Epidemiologic studies have found inverse associations between allergy and the development of certain tumors. The authors sought to determine if there was an association between asthma and ovarian cancer. A case-control study was conducted using Florida hospital data (year 2001). Discharge diagnoses were coded using the ICD-9-CM (International Classification of Diseases, Ninth Revision, Clinical Modification). Cases were 1,582 women whose principal discharge diagnosis was a malignant neoplasm of the ovary. Two control series were used: 4,744 women whose principal diagnosis was an upper limb bone fracture, and 21,830 women whose principal diagnosis was an acute myocardial infarction. Odds ratios (ORs) adjusted for age, race-ethnicity, Medicaid status, obesity, and smoking were calculated. Cases were 30% less likely than fracture control to be asthmatics (adjusted OR = 0.70, 95% confidence interval [CI]: 0.49-0.99, p = .04). Similarly, cases when compared to acute myocardial infarction controls were significantly less likely to have asthma (adjusted OR = 0.62, 95% CI: 0.45-0.87, p = .005). The results of this statewide exploratory study suggest that individuals with asthma may have a lower risk of developing ovarian cancer than nonasthmatics.