Abdominal obesity is essential for the risk of venous thromboembolism in the metabolic syndrome: the Tromsø study.

Abstract

The metabolic syndrome is a cluster of cardiovascular risk factors, including abdominal obesity, hypertension, dyslipidemia and insulin resistance, associated with increased risk of cardiovascular diseases and all cause mortality. The purpose of the study was to assess the impact of the metabolic syndrome, and its individual components, on the risk of venous thromboembolism (VTE) in a prospective population-based study. Individual components of the metabolic syndrome were registered in 6170 subjects aged 25-84 years in the Tromsø Study in 1994-1995, and first ever VTE events were registered until 1 September 2007. The metabolic syndrome was present in 21.9% (1350 subjects) of the population. There were 194 validated first VTE events (2.92 per 1000 person-years) during a mean of 10.8 years of follow-up. Presence of metabolic syndrome was associated with increased risk of VTE (HR, 1.65; 95% CI, 1.22-2.23) in age- and gender-adjusted analysis. The risk of VTE increased with the number of components in the metabolic syndrome (P < 0.001). Abdominal obesity was the only component significantly associated with VTE in multivariable analysis including age, gender, and the individual components of the syndrome (HR, 2.03; 95% CI, 1.49-2.75). When abdominal obesity was omitted as a diagnostic criterion, none of the other components, alone or in cluster, was associated with increased risk of VTE. Our study provides evidence for the metabolic syndrome as a risk factor for TE. Abdominal obesity appeared to be the pivotal risk factor among the individual components of the syndrome.