Exploratory study of predictors of decreased ability to perform activities of daily living in people living with hand osteoarthritis

OBJECTIVE: People with hand osteoarthritis (OA) report decreased ability to perform activities of daily living (ADL). However, few are referred to occupational therapy by their general practitioner. This study aimed to identify clinical predictors of decreased ADL ability in people with hand OA as markers of the need for referral to occupational therapy.

METHOD: A cross-sectional study was conducted as an independent add-on to a randomized controlled trial of adults with hand OA (the COLOR trial). Measures of self-reported (ADL Interview) and observed (Assessment of Motor and Process Skills) ADL ability were collected. Data representing potential predictors identified by stakeholders were extracted from the COLOR trial: age, sex, symptom duration, hand OA type, grip strength, pain, stiffness, function, illness perception, and health-related quality of life. Correlational analyses and prediction models were used.

RESULTS: Correlations between ADL ability and potential predictors in the 62 participants were low to negligible (r < 0.5). Based on root mean square error (RMSE) estimates, prediction models for observed ADL motor (RMSE = 0.3) and ADL process (RMSE = 0.2) ability were more accurate than for self-reported ADL ability (RMSE = 0.6). However, these variables only predicted observed ADL motor and ADL process ability with 16% (adjusted Rs = 0.163) and 12% (adjusted Rs = 0.120) accuracy, respectively.

CONCLUSION: The findings suggest that variables representing body functions, perceived health, and quality of life do not predict ADL ability among people living with hand OA. An adequately powered study is recommended to explore this topic further.