OBJECTIVES: Inflammation and increased blood viscosity are associated with increased risk of cardiovascular mortality. Erythrocyte sedimentation rate (ESR) and hematocrit both influence blood viscosity whereas the first also is a marker of inflammation. We aimed to investigate ESR, hematocrit and the interaction between them as predictors of cardiovascular mortality during 26 years follow-up among healthy middle aged men. DESIGN: Four hundred and eighty eight men aged 40-59 were extensively examined in 1972-1975 and followed over a period of 26 years. Risk estimation was made in Cox proportional hazards and adjusted for age, smoking, systolic blood pressure, total serum cholesterol, and physical fitness. RESULTS: A 2.44-fold (95% CI 1.37-4.35) adjusted risk of cardiovascular mortality was found in the highest quartile of hematocrit compared to the lowest. Among the 265 men who had an ESR
