Racial differences in osteoarthritis pain and function: potential explanatory factors

SummaryObjectiveThis study examined factors underlying racial differences in pain and function among patients with hip and/or knee osteoarthritis (OA).MethodsParticipants were n=491 African Americans and Caucasians enrolled in a clinical trial of telephone-based OA self-management. Arthritis Impact Measurement Scales-2 (AIMS2) pain and function subscales were obtained at baseline. Potential explanatory variables included arthritis self-efficacy, AIMS2 affect subscale, problem- and emotion-focused pain coping, demographic characteristics, body mass index, self-reported health, joint(s) with OA, symptom duration, pain medication use, current exercise, and AIMS2 pain subscale (in models of function). Variables associated with both race and pain or function, and which reduced the association of race with pain or function by ≥10%, were included in final multivariable models.ResultsIn simple linear regression models, African Americans had worse scores than Caucasians on AIMS2 pain (B=0.65, P=0.001) and function (B=0.59, P