General practitioners retiring or relocating and its association with healthcare use and mortality: a cohort study using Norwegian national data.

Background: Continuity in the general practitioner (GP)-patient relationship is associated with better healthcare outcomes. However, few studies have examined the impact of permanent discontinuities on all listed patients when a GP retires or relocates.

Aim: To investigate changes in the Norwegian population's overall healthcare use and mortality after discontinuity due to Regular GPs retiring or relocating.

Methods: Linking national registers, we compared days with healthcare use and mortality for matched individuals affiliated with Regular GPs who retired or relocated versus continued. We included list patients 3 years prior to exposure and followed them up to 5 years after. We assessed changes over time employing a difference-in-differences design with Poisson regression.

Results: From 2011 to 2020, we identified 819 Regular GPs retiring and 228 moving, affiliated with 1 165 295 people. Relative to 3 years before discontinuity, the rate ratio (RR) of daytime GP contacts, increased 3% (95% CI 2 to 4) in year 1 after discontinuity, corresponding to 148 (95% CI 54 to 243) additional contacts per 1000 patients. This increase persisted for 5 years. Out-of-hours GP contacts increased the first year, RR 1.04 (95% CI 0.99 to 1.09), corresponding to 16 (95% CI -5 to 37) contacts per 1000 patients. Planned hospital contacts increased 3% (95% CI 2 to 4) in year 1, persisting into year 5. Acute hospital contacts increased 5% (95% CI 3 to 7), primarily in the first year. These 1-year effects corresponded to 51 (95% CI 18 to 83) planned and 13 (95% CI 7 to 18) acute hospital contacts per 1000 patients. Mortality was unchanged up to 5 years after discontinuity.

Conclusion: Regular GPs retirement and relocation were associated with small to moderate increases in healthcare use among listed patients, while mortality was unaffected.