Patients’ Perceived Continuity of Care and Adherence to Oral Anticancer Therapy: a Prospective Cohort Mediation Study

Background: Oral anticancer therapy (OACT) poses adherence-related challenges to patients while generating a setting in which both primary care physicians (PCPs) and oncologists are involved in the active treatment of cancer. Continuity of care (COC) was shown to be associated with medication adherence. While maintaining COC is a central role of the PCP, how this affects continuity with oncologists, and jointly affects OACT adherence, is yet unknown. Objectives: To explore how aspects of COC act together to promote OACT adherence. Specifically, to examine whether better personal continuity with the PCP leads to better personal continuity with the oncologist, which together lead to better cross-boundary continuity between the oncologist and the PCP, jointly leading to good adherence to OACT. Design and Setting: A prospective cohort study conducted in five oncology centers in Israel. A bootstrapping method was used to test the serial mediation model. Participants: Adult patients (age > 18 years) receiving a first OACT prescription (n = 119) were followed for 120 days. Main Measures: The Nijmegen Continuity Questionnaire was used to assess patients’ perceived personal and cross-boundary continuity. The medication possession ratio was used to measure adherence. Key Results: Better personal continuity with the PCP was associated with better personal continuity with the oncologist (B = 0.35, p < 0.001), which was associated with better cross-boundary continuity (B = 0.33, p < 0.001), which, in turn, was associated with good adherence to OACT (B = 0.46, p = 0.03). Additionally, the indirect effect of personal continuity with the PCP on adherence to OACT through the mediation of personal continuity with the oncologist and cross-boundary continuity was found to be statistically significant (B = 0.053, 95% CI 0.0006–0.17). Conclusions: In a system where the PCP is the case manager, cancer patients’ perceived personal continuity with the PCP has an essential role for initiating a sequence of care delivery events that positively affect OACT adherence.