Using the common sense model of illness to examine interrelationships between symptom severity and health outcomes in end-stage osteoarthritis patients

Abstract

Objective. The aim was to evaluate the utility of the common sense model (CSM) in characterizing contributors to psychological well-being and quality of life (QoL) in patients with end-stage OA. Methods. One hundred and twenty patients [34 males, 86 females; mean (S.D.) age 65.52 (9.14) years] with end-stage OA (57.5% hip, 42.5% knee) were recruited. OA symptom severity was evaluated according to the WOMAC; coping styles were assessed with the Carver Brief COPE scale illness perceptions were explored with the Brief Illness Perceptions Questionnaire; self-efficacy was assessed with the Arthritis Self-efficacy scale anxiety, depression and overall distress were measured using the Hospital Anxiety and Depression Scale and QoL was assessed using the WHO Quality of Life-short version. The CSM was used to explore the interrelationships between OA symptom severity, illness perceptions and coping strategies in patients. Results. Two structural equation models were developed, with both found to have good fit. Consistent with the CSM, the standard model indicated that self-reported OA symptom severity directly influenced illness perceptions, which in turn had direct impacts upon maladaptive coping, distress and QoL. The addition of self-efficacy to the CSM resulted in a complex interaction, with OA severity directly influencing self-efficacy and self-efficacy influencing maladaptive coping, distress and QoL. Conclusion. We found interrelationships amongst OA activity, illness perceptions, coping strategies, selfefficacy, psychological distress and QoL broadly consistent with the CSM. The CSM may help inform the approach to the psychological support that patients with end-stage OA often require.