Continuity of care and mortality in patients with type 2 diabetes.

Background: How continuity of general practitioner care (GP-CoC) affects mortality in patients with type 2 diabetes (T2D) is unclear.

Aim: The aim of this study was to examine the effect of having no continuity of care (CoC) and GP-CoC on mortality in primary health care (PHC) patients with T2D.

Design & setting: Cohort study in patients aged 60 years or older with T2D within the public PHC of the city of Vantaa, Finland.

Method: Inclusion period was between 2002-2011 and follow-up period between 2011-2018. Six groups were formed (no appointments, one appointment and Modified, Modified Continuity Index [MMCI] quartiles). Mortality was measured with standardized mortality ratio (SMR) and adjusted hazard ratio (aHR). GP-CoC was measured with MMCI. Comorbidity status was determined with Charlson comorbidity index (CCI).

Results: In total 11,020 patients were included. Mean follow-up time was 7.3 years. SMRs for the six groups (no appointments, one appointment, MMCI quartiles) were 2.46 (95%CI: 2.24-2.71), 3.55 (3.05-4.14), 1.15 (1.06-1.25), 0.97 (0.89-1.06), 0.92 (0.84-1.01) and 1.21 (1.11-1.31), respectively. With continuous MMCI, mortality formed a u-curve. The inflection point was at a MMCI value of 0.65 with corresponding SMR of 0.86. Age and CCI adjusted HR for death between men and women was 1.45 (1.35-1.58).

Conclusions: Patients with no CoC had the highest mortality. In patients having care over time, the effect of GP-CoC on mortality was minor and mortality turned to rise with high GP-CoC.