Background: Risk factors for deep vein thrombosis and pulmonary embolism are mostly derived from case-control studies of hospitalized patients, and there are few long-term population-based studies.
Objective: To study the long-term risk factors for deep vein thrombosis and pulmonary embolism among middle-aged men.
Design: A prospective cohort study.
Setting: General community, "The Study of Men Born in 1913."
Subjects: A random population sample of 855 men, all aged 50 years at baseline.
Main outcome measures: Eight-hundred fifty-five men participated in a screening examination in 1963 at the age of 50 years, and 792 of these men were reexamined in 1967 at the age of 54. All the men were followed up with periodic examinations until the age of 80. Objective methods were used to ascertain a diagnosis of deep vein thrombosis or pulmonary embolism.
Results: Waist circumference (P=.004) and smoking (P = .02) predicted a venous thromboembolic event in multivariate survival analysis. Men in the highest decile of waist circumference (> or =100 cm) had an adjusted relative risk of 3.92 (95% confidence interval, 2.10-7.29; P<.001) compared with men with a waist circumference of less than 100 cm. For men who smoked 15 g of tobacco (15 cigarettes) a day or more, the adjusted relative risk was 2.82 (95% confidence interval, 1.30-6.13; P= .009) compared with nonsmokers.
Conclusions: Smoking and abdominal obesity were independent risk factors for venous thromboembolic events during follow-up. In addition to the prevention of smoking and obesity, a more aggressive strategy regarding the use of prophylactic agents among smokers and obese patients, in various risk situations, may be justified.