Does diet influence the risk of venous thromboembolism?

The results of the first prospective study on diet and the risk of venous thromboembolism (VTE) were recently reported by Steffen and colleagues. The bottom line: higher consumption of fish, fruit, and vegetables and lower consumption of red meat and processed meat are associated with reduced risk of VTE.

Their study included close to 15,000 middle-aged adults who were participating in the Atherosclerosis Risk in Communities Study. Over 12 years, 196 cases of VTE were validated by chart review. A questionnaire was used to assess dietary intake at baseline and at year 6. Proportional hazards regression analyses were performed, with adjustment for demographic and lifestyle variables, body mass index, and diabetes.

Hazard ratios across quintiles of intake for different food groups demonstrated a reduced risk of VTE with higher intake of fruits and vegetables and an increased risk with higher intake of red meat and processed meat. There appeared to be a threshold effect for fish consumption; for quintiles 2 through 5, eating fish 1 or more times per week was associated with a 30% to 45% lower incidence of VTE, compared with quintile 1. The hazard ratios were affected only slightly after adjustment for factors VIIc and VIIIc and von Willebrand factor.

The finding that increased dietary intake of vitamin B₆ and folate is associated with reduced risk of VTE supports the contention that homocysteine is a risk factor. An unexpected finding was that consumption of whole grain foods was not associated with reduced risk.