Coffee consumption and the risk of venous thromboembolism: the Tromsø study

Abstract

Background: Several studies have investigated the association between coffee consumption and cardiovascular disease, but little is known about coffee intake and the risk of venous thromboembolism (VTE).

Objective: The aim of this prospective cohort study was to investigate the association between coffee consumption and the risk of incident VTE in a general population.

Methods: Information about coffee consumption habits was obtained with a self-administered questionnaire in 26, 755 subjects, aged 25-97 years, who participated in the fourth survey of the Tromsø study (1994-1995). Incident VTE events were registered until the end of follow-up, 1 September 2007.

Results: There were 462 incident VTE events (1.60 per 1000 person-years, 95% confidence interval [CI] 1.46-1.75) during a median of 12.5 years of follow-up. A daily consumption of three to four cups was borderline associated (hazard ratio [HR] 0.70; 95% CI 0.48-1.02) and a daily consumption of five to six cups (HR 0.67; 95% CI 0.45-0.97) was significantly associated with reduced risk of VTE as compared with coffee abstainers in multivariable analysis adjusted for age, sex, body mass index (BMI), smoking status, physical activity, diabetes, history of cardiovascular disease and cancer. Similar risk estimates were found for provoked and unprovoked VTE, and in sex-stratified analyses.

Conclusion: Our findings suggest a possible U-shaped relationship between coffee consumption and VTE, and that moderate coffee consumption may be associated with a reduced risk of VTE. However, more studies are needed to establish whether moderate coffee consumption is inversely associated with the risk of VTE.