Knee pain prevalence and associated factors in a Brazilian population study

To estimate the association among knee pain and central obesity.

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, sociodemographic characteristics and abdominal circumference measurement. Unadjusted (bivariate analysis) and adjusted odds ratio (OR) and 95%CI were estimated by using backward stepwise logistic regression.

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, CI [confidence interval] 2.01-3.63), older age (OR 2.98, CI 1.89-4.42), and obesity (OR 1.62, CI 1.22-2.15). Adjusted ORs (P<0.05) were found for obesity-married individuals (OR 4.69, CI 1.09-20.11), separated (OR 11.03, CI 2.09-58.20) or widowed (OR 7.17, CI 1.40-36.61), and male (OR 2.35, CI 1.25-4.41). The OR of nonobese men was 2.66, CI 1.74-4.06, but being married seems to protect them of knee pain (OR 0.66, CI 0.45-0.96).

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.