OVERWEIGHT, GENDER AND KNEE OSTEOARTHRITIS

A 10-year follow-up study was carried out among 6647 farmers aged 40-6 4 y to investigate associations between age, gender. body mass index ( weight/height(2)) and the incidence of disabling knee osteoarthritis. After the follow-up (1980-1990) a record linkage with the Social Insur ance Institution's register was made to identify disability pensions. All the medical certificates for the disability pensions (N = 965) wer e reviewed to find out the incident cases (N = 126). Age, female gende r and body mass index were all independent predictors of disabling kne e osteoarthritis. The relationship between body mass index and the inc idence of disabling knee osteoarthritis was linear. the adjusted relat ive risk was 1.4 (95% CI, 1.2-1.5) per standard deviation of the index (3.8 kg/m(2)). In women. as compared with men. the adjusted relative risks (95% confidence intervals) of right unilateral, left unilateral and bilateral knee osteoarthritis were 7.0 (2.5-19.7). 3.3 (1.1-9.8) a nd 4.8 (2.4-9.3), respectively. Overweight is a strong risk factor for disabling knee osteoarthritis.