Little information is available on the prevalence and determinants of valvular regurgitation in the general population. This study sought to assess the prevalence and clinical determinants of mitral (MR), tricuspid (TR), and aortic (AR) regurgitation in a population-based cohort. Color Doppler echocardiography was performed in 1,696 men and 1,893 women (aged 54 +/- 10 years) attending a routine examination at the Framingham Study. After excluding technically poor echocardiograms, MR, TR, and AR were qualitatively graded from trace to severe. Multiple logistic regression analysis was used to examine the association of clinical variables with MR and TR (more than or equal to mild severity) and AR (more than or equal to trace severity). MR and TR of more than or equal to mild severity was seen in 19.0% and 14.8% of men and 19.1% and 18.4% of women, respectively, and AR of more than or equal to trace severity in 13.0% of men and 8.5% of women. The clinical determinants of MR were age (odds ratio [OR] 1.3/9.9 years, 95% confidence interval [CI] 1.2 to 1.5), hypertension (OR 1.6; 95% CI 1.2 to 2.0), and body mass index (OR 0.8/4.3 kg/m2; 95% CI 0.7 to 0.9). The determinants of TR were age (OR 1.5/9.9 years; 95% CI 1.3 to 1.7), body mass index (OR 0.7/4.3 kg/m2; 95% CI 0.6 to 0.8), and female gender (OR 1.2; 95% CI 1.0 to 1.6). The determinants of AR were age (OR 2.3/9.9 years; 95% CI 2.0 to 2.7) and male gender (OR 1.6; 95% CI 1.2 to 2.1). A substantial proportion of healthy men and women had detectable valvular regurgitation by color Doppler echocardiography. These data provide population-based estimates for comparison with patients taking anorectic drugs.