Abnormally high prevalence of major components of the metabolic syndrome in subjects with early-onset idiopathic venous thromboembolism

Background: Although patients with idiopathic VTE are at higher than normal risk of asymptomatic atherosclerosis and of cardiovascular events, the impact of cardiovascular risk factors on VTE is poorly understood.

Objective: To assess the prevalence of the metabolic syndrome and of its components in patients with early-onset idiopathic VTE.

Methods: As many as 323 patients referred to our Thrombosis Ward for a recent (<6-months) early-onset idiopathic venous thromboembolism (VTE), were compared with 868 gender- and age-matched subjects, in whom a history of venous thrombosis had been excluded, referred during the same period time to our Ward. All had undergone a clinical assessment for smoking habits and for the presence of the components of the metabolic syndrome.

Results: The metabolic syndrome was detected in 76/323 cases (23.5%) and in 81/868 controls (9.3%) (p<0.001; OR:2.990; 95%C.I.:2.119-4.217). Smoking was more common in patients with idiopathic VTE than in controls. In addition to the metabolic syndrome as a whole, its major individual determinants (arterial hypertension, impaired fasting glucose plasma levels, abdominal obesity, hypertriglyceridemia, low HDL-cholesterol) significantly correlated with idiopathic VTE (p always <0.05). The prevalence of thrombotic events was lower in females than in males (p=0.000; OR:2.217), the latter being most often hypertensives, smokers, hypertriglyceridemics, carriers of a metabolic syndrome and of impaired fasting glucose than females. In a multivariate analysis, arterial hypertension, impaired fasting glucose, abdominal obesity, and hypercholesterolemia independently predicted idiopathic venous events.

Conclusions: Both metabolic syndrome as a whole and its major components individually considered, independently predict early-onset idiopathic VTE.