Prevalence rates for and predictors of self-reported adherence of oncology outpatients with analgesic medications

Objectives: Inadequate adherence with an analgesic regimen may be a reason why oncology patients experience unrelieved pain. However, only a limited number Of Studies have evaluated the prevalence rates for adherence and no studies have attempted to determine predictors of adherence in patients with cancer pain. On the basis of concepts from the Health Belief Model, the purposes of this study were to describe oncology Outpatients' level of adherence with an analgesic regimen and to evaluate the direct and indirect effects of selected demographic variables, pain characteristics, barriers to pain management, and self-efficacy (SE) on adherence with an analgesic regimen. Methods: A descriptive, cross-sectional Study recruited outpatients from oncology clinics in a large, tertiary referral cancer hospital in Norway. A sample of 174 oncology Outpatients completed a demographic questionnaire, the Brief Pain Inventory, 2 self-reported adherence measures, the Barriers Questionnaire, and a SE questionnaire. Results: Only 41% of the patients were adherent with their analgesic regimen. In the regression analysis, 29.9% of the variance in adherence was explained. Higher adherence scores were associated with male sex, and also lower SE for physical function scores, higher average pain intensity scores, higher pain relief scores, and the use of strong opioid analgesics. Conclusions: Improvements in pain management may occur if clinicians routinely assessed patients' level of adherence with their analgesics regimen.