Anthropometric measures of obesity and risk of venous thromboembolism: the Tromso study.

OBJECTIVE The purpose of this study was to assess the impact of various obesity measures on identification of subjects at risk and their respective risk estimates for VTE in a prospective population-based study. METHODS AND RESULTS Measures of body composition such as body mass index (BMI), waist circumference (WC), hip circumference (HC), and waist-hip ratio (WHR) were registered in 6708 subjects aged 25 to 84 years, who participated in the Tromsø Study (1994-1995). Incident VTE-events were registered during follow-up until September 1, 2007. There were 222 VTE-events during a median of 12.3 years of follow-up. All measures of obesity exhibited significantly increased HR for VTE in multivariable models with highest risk estimates for WC in both genders. The risk of VTE increased across quartiles of BMI, WC, and HC in both genders, but not for WHR. WC identified more subjects at risk using established criteria for obesity. WC had the highest area under the curve in both genders in ROC analysis, and WC above ROC-derived cut-off values (WC > or =85 cm in women and > or =95 cm in men) were associated with HRs of 1.92 (95% CI: 1.05 to 3.48) in women and 2.78 (95% CI: 1.47 to 5.27) in men. CONCLUSIONS Our findings indicate that WC is the preferable anthropometric measure of obesity to identify subjects at risk and to predict risk of VTE.