Association between different obesity measures and the risk of stroke in the EPIC Spanish cohort.

Introduction: There is still a scientific debate on the exact role played by obesity on stroke risk.

Objective: The aim of the study was to analyze the association between obesity, measured by different indices such as body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR) and a new one called A Body Shape Index (ABSI) and the risk of total and ischemic stroke.

Subjects/methods: A total of 41,020 subjects (15,490 men and 25,530 women) aged 29-69 years participated in the study. All participants were recruited between 1992 and 1996 and followed up until 2008 to ascertain incident cerebrovascular disease events. Cox proportional hazards models were designed to estimate the relative risk and 95% CI between obesity and cerebrovascular disease incidence.

Results: After 13.8 years of follow-up, a total of 674 stroke cases (55.3% in men) were registered (531 ischemic, 79 hemorrhagic, 42 subarachnoid hemorrhage and 22 unspecified). WC fourth quartile (HR 1.95; 95% CI 1.20-3.19) and WHR fourth quartile (HR 1.58; 95% CI 1.12-2.25) were positively associated with total stroke only in men. BMI was not associated with stroke incidence. The new index, ABSI, was significantly associated with total stroke incidence only in men (HR 1.54; 95% CI 1.06-2.23).

Conclusions: Data from the Spanish EPIC cohort study show a strong association of WC and WHR with the relative risk of suffering a stroke only in men, while no associations were found for BMI. It supports the suggestion of other authors of using more than one obesity index in the study of stroke risk prediction.