High white blood cell and neutrophil counts identify patients at increased cardiovascular risk in various clinical settings. However, the prognostic value of white blood cell and neutrophil counts in hypertensive postmenopausal women is unknown. We tested the independent prognostic value of total white blood cell and neutrophil counts for cardiovascular events in hypertensive postmenopausal women. We examined 298 initially untreated postmenopausal women with essential hypertension who were part of Progetto Ipertensione Umbria Monitoraggio Ambulatoriale (PIUMA). Mean duration of follow-up was 8 years (range 1-20 years). Treatment was tailored to each individual. Mean age at entry was 59 years. Diabetic women comprised 9.1% of the group, and current smokers comprised 17.5% of the group. During follow-up, 31 new major cardiovascular events occurred. In univariable analyses, age, diabetes, serum creatinine, blood pressure, left ventricular hypertrophy, and neutrophil count showed an association with the risk of events (all P<.05). In a multivariable Cox analysis, after adjustment for traditional cardiovascular risk factors, for each 1.25x10 (1 standard deviation) increase in neutrophil count there was a 67% higher risk of cardiovascular events (hazard ratio 1.67, 95% confidence interval 1.32-2.07; P<.001). Furthermore, neutrophil count showed robust incremental predictive value for cardiovascular events, in addition to traditional risk factors. Total white blood cell count did not show any association with cardiovascular events. A high peripheral neutrophil count identifies postmenopausal hypertensive women at increased risk of cardiovascular disease. Such relation appears to be independent of traditional risk factors. III.