Knee Pain Prevalence and Associated Factors in a Brazilian Population Study

Objectives. To estimate the association among knee pain and central obesity. Methods. A cross-sectional study was carried out in Salvador, Brazil, with a sample of 2,297 individuals >= 20 years of age. A standardized questionnaire was applied at home to collect data about pain, socio-demographic characteristics and abdominal circumference measurement. Unadjusted (bivariate analysis) and adjusted odds ratio (OR) and 95%Cl were estimated by using backward stepwise logistic regression. Results. The prevalence of knee pain was found in 11.2% of the studied sample. Unadjusted OR associations (P < 0.1) were found for male (OR 2.70, Cl [confidence interval] 2.01-3.63), older age (OR 2.98, Cl 1.89-4.42), and obesity (OR 1.62, Cl 1.22-2.15). Adjusted ORs (P < 0.05) were found for obesity-married individuals (OR 4.69, Cl 1.09-20.11), separated (OR 11.03, CI 2.09-58.20) or widowed (OR 7.17, C11.40-36.61), and male (OR 2.35, Cl 1.25-4.41). The OR of nonobese men was 2.66, Cl 1.74-4.06, but being married seems to protect them of knee pain (OR 0.66, Cl 0.45-0.96). Conclusion. In this study, we found a knee pain prevalence of 11.2% and positive association with the male gender, married, separated or widowed, and a protective association for knee pain in nonobese married male. Aging, obesity, and excessive alcohol consumption were independent correlates of knee pain in the studied population sample.