Association Between Team-Based Continuity of Care and Risk of Cardiovascular Diseases Among Patients With Diabetes: A Retrospective Cohort Study

Cardiovascular diseases (CVD) are a long-term sequela of diabetes. Better individual-based continuity of care has been reported to reduce the risk of chronic complications among patients with diabetes. Maintaining a one-to-one patient-physician relationship is often challenging, especially in public health care settings. This study aimed to evaluate the relationship between higher team-based continuity of care, defined as consultations provided by the same physician team, and CVD risks in patients with diabetes from public primary care clinics. This was a retrospective cohort study in Hong Kong of 312,068 patients with type 2 diabetes and without any history of CVD at baseline (defined as the earliest attendance at a doctor's consultation in a public-sector clinic between 2008 and 2018). Team-based continuity of care was measured using the usual provider continuity index (UPCI), calculated by the proportion of consultations provided by the most visited physician team in the 2 years before baseline. Patients were divided into quartiles based on their UPCI, and the characteristics of the quartiles were balanced using propensity score fine stratification weights. Multivariable Cox regression was applied to assess the effect of team-based continuity of care on CVD incidence. Patient demographics, smoking status, physiological measurements, number of attendances, comorbidities, and medications were adjusted for in the propensity weightings and regression analyses. After an average follow-up of 6.5 years, the total number of new CVD events was 52,428. Compared with patients in the 1st quartile, patients in the 2nd, 3rd, and 4th quartiles of the UCPI had a CVD hazard ratio (95% CI) of 0.95 (0.92-0.97), 0.92 (0.89-0.94), and 0.87 (0.84-0.89), respectively, indicating that higher continuity of care was associated with lower CVD risks. The subtypes of CVD, including coronary heart disease and stroke, also showed a similar pattern. Subgroup analyses suggested that patients