Hispanics may carry a similar burden of increased left ventricular mass (LVM) as non-Hispanic blacks but whether LVM portends a worse outcome among Hispanics is largely unknown. We prospectively evaluated 1081 Hispanics enrolled in the Northern Manhattan Study during the period of 1993 to 2001. Subjects were aged > or =40 years and free of prior myocardial infarction or stroke. LVM was defined echocardiographically and indexed for height(2.7). Cox proportional hazards models were used to assess the risk of vascular events with adjustments for age, gender, systolic blood pressure, diabetes, and smoking. LVM averaged 48.4+/-15 gm/ht(2.7) and on multivariate analysis was significantly associated with the combined end point of myocardial infarction, stroke, or vascular death (adjusted hazard ratio 1.34 per SD change in LVM [95% CI 1.10 to 1.63]). During a mean of 57 months of follow-up, 74 vascular events occurred. The annual rate of vascular events was 21.8 per 1000 patient-years in the highest quartile of LVM and 8.6 per 1000 patient-years in the lowest quartile (P=0.007). These data demonstrate in a large population-based sample that increased LVM yields independent prognostic information among Hispanics, predicting a higher incidence of events attributable to vascular disease in this understudied population. Our findings identify the Hispanic population with increased LVM as a high-risk subgroup.