Oral contraceptives, smoking, and other factors in relation to risk of venous thromboembolic disease
Petitti, D.B.; Wingerd, J.; Pellegrin, F.; Ramcharan, S.
American Journal of Epidemiology 108(6): 480-485
1978
ISSN/ISBN: 0002-9262 PMID: 736027 DOI: 10.1093/oxfordjournals.aje.a112646Document Number: 437283
Analysis of data from the Walnut Creek Contraceptive Drug Study [California, USA] showed a significant increase in risk of venous thromboembolic disease in the absence of surgery, trauma, malignancy, pregnancy and the puerperium for women with a previous history of thromboembolism, hypertension, diabetes, varicose veins, gallbladder disease and cigarette smoking. Education, marital status, parity, use of noncontraceptive estrogens and obesity were not associated with an increase in risk of the disease. When only cases of the disease in the absence of all known predisposing causes (idiopathic cases) were analyzed, oral contraceptive use and smoking remained as independent risk factors; there was no evidence of a positive interaction between them.