To examine use of complementary and alternative medicine (CAM) among individuals with radiographic-confirmed osteoarthritis (OA) of the knee.
We included 2679 participants of the Osteoarthritis Initiative with radiographic tibiofemoral knee OA in at least one knee at baseline. Trained interviewers asked a series of specific questions relating to current OA treatments including CAM therapies (seven categories - alternative medical systems, mind-body interventions, manipulation and body-based methods, energy therapies, and three types of biologically based therapies) and conventional medications. Participants were classified as: (1) conventional medication users only, (2) CAM users only; (3) users of both; and (4) users of neither. Polytomous logistic regression identified correlates of treatment approaches including sociodemographics and clinical/functional correlates.
CAM use was prevalent (47%), with 24% reporting use of both CAM and conventional medication approaches. Multi-joint OA was correlated with all treatments (adjusted odds ratios (aOR) conventional medications only: 1.62; CAM only: 1.37 and both: 2.16). X-ray evidence of severe narrowing (OARSI grade 3) was associated with use of glucosamine/chondroitin (aOR: 2.20) and use of both (aOR: 1.98). The Western Ontario and McMaster Universities (WOMAC)-Pain Score was correlated with conventional medication use, either alone (aOR: 1.28) or in combination with CAM (aOR: 1.41 per one standard deviation change). Knee Outcomes in Osteoarthritis Survey (KOOS)-Quality of Life (QOL) and Short Form (SF)-12 Physical Scale scores were inversely related to all treatments.
CAM is commonly used to treat joint and arthritis pain among persons with knee OA. The extent to which these treatments are effective in managing symptoms and slowing disease progression remains to be proven.