Callhoff J, Albrecht K, Redeker I, et al. - Through a random sample of 8,995 persons with OA from German statutory health, researchers investigated factors correlated with the burden of OA, considering the pattern of joint involvement. Persons with knee (n = 1,448), hip (n = 959), knee and hip (n = 399) or polyarthritic (n = 758) OA were involved. Concomitant knee and hip OA was supplemented by the highest Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) values, common impairment of personal life and the highest use of analgesics. In the regression analyses, BMI per 5 units and WHO-5 per 10% worsening were related to an elevation in WOMAC values of 4-5 points, despite the joint manifestations. Thus, in persons with concomitant knee and hip OA, the disease burden is high going along with the regular prescription of analgesics. Moreover, when using the WOMAC as an outcome instrument, the involvement of several joints, BMI and depressive symptoms require to be acknowledged.