How relational continuity shapes recommended chronic disease management: analysis of population-based administrative health data in British Columbia

Relational continuity, or the ongoing therapeutic relationship between patient and clinician, has been associated with improved outcomes among people with chronic disease and emphasized in primary care policy. It has not yet been studied how relational continuity shapes recommended chronic disease management and whether this relationship is modified by patient complexity. We used linked administrative health data to conduct a retrospective, population-based cohort study among residents of British Columbia, Canada with diabetes and/or hypertension between April 1, 2020 to March 31, 2023. Modified-Poisson regression models were used to calculate adjusted risk ratios (aRR) between relational continuity and a composite outcome of recommended management (including monitoring and prescribing for diabetes or hypertension) and included interaction terms to examine subgroup-specific associations among those treated for serious mental illness, substance use disorder, or with a higher overall burden of comorbidity. Compared to those with low relational continuity, those with complete relational continuity had slightly more recommended management for both diabetes (20.4% vs. 19.2%) and hypertension (28.4% vs. 26.8%). However, when adjusting for other patient characteristics, there was a null association between relational continuity and recommended management overall (aRR: 1.00, 95% confidence interval [CI] 0.99 to 1.01). We note significant inverse associations among those treated for serious mental illness (SMI) or with high comorbidity, particularly with high primary care use (12 + visits and SMI aRR: 0.64 [0.52–0.80]; 12 + visits and Charlson comorbidity score > 1 aRR: 0.91 (0.86–0.96)]). Relational continuity was not associated with recommended chronic disease management processes. Inverse associations observed among patient subgroups with more complex needs suggests that emphasis on visit-based measures of relational continuity has been ineffective at facilitating complex care. Improving other aspects of continuity, like management and informational continuity, may be important to providing comprehensive and equitable primary care.