Low vegetable intake is strongly associated with venous thromboembolism in Thai population.

Recent studies have demonstrated a much higher incidence of venous thromboembolism (VTE) among Asian patients compared with previous studies. This study aims to determine dietary and behavioral factors that may have contributed to this increase. A case-control study was conducted. Cases were objectively confirmed VTE between 2006 and 2009 at King Chulalongkorn Memorial Hospital. Patients with underlying cancer, antiphospholipid syndrome and arterial thrombosis were excluded. Controls were age and sex-matched healthy volunteers. Food consumption was assessed using a food frequency questionnaire modified from the Thailand National Health Examination Survey III previously validated in the Thai population. There were 97 cases and 195 controls. The mean age was 54.6 years and 70% were women. VTE patients consumed significantly less vegetable, fish and spicy food compared with normal individuals with an odds ratio (OR) for venous thrombosis of 3.74 [95% confidence interval (CI) 2.24-6.26, P < 0.001], 2.05 (95% CI 1.24-3.41, P = 0.005) and 2.30 (95% CI 1.29-4.11, P = 0.01), respectively. Additionally, thrombosis was associated with overweight (OR 2.1, 95% CI 1.21-3.62, P = 0.002), obesity (OR 3.1, 95% CI 1.46-6.74, P = 0.001) and estrogen uses (OR 3.7, 95% CI 1.05-13.2, P = 0.02), but not with smoking or lack of exercise. A multivariate analysis showed that low vegetable consumption (OR 3.74, 95% CI 1.85-7.55, P < 0.001), female hormones (OR 5.80, 95% CI 1.51-22.22, P = 0.011) and body mass index (BMI, P = 0.048) were independently associated with VTE. Low vegetable intake, hormonal use and high BMI are the risk factors for noncancer-related VTE in Thai population.