Association of General Practice Continuity With Hospital Admissions and Costs: A Retrospective Study

PURPOSE: Continuity of care has been associated with lower health care use and costs. When general practitioners (GPs) serve as gatekeepers to hospital care, having an ongoing relationship with a GP may promote more efficient care and reduce urgent referrals, thereby lowering costs. We examined the association of 2 conceptually distinct measures of continuity in general practice with both urgent hospital admissions and hospital costs. METHODS: We conducted a retrospective cohort study using routinely collected health care data from 100,450 adults in 48 Dutch general practices (2013-2018) who were linked to national hospital admission and cost records (2019). Continuity was separately measured by duration of GP-patient relationship (time registered with the practice) and by density of GP contacts (Herfindahl-Hirschman index). We assessed associations with urgent admissions and log-transformed hospital costs using multilevel logistic and linear models, adjusting for sex, age, comorbidity, migration background, and income. RESULTS: Compared with individuals registered with their practice for 0 to 5 years, those registered longer had 9% to 21% lower odds of urgent hospital admission, with the lowest odds seen in the group registered 15 to 20 years (adjusted odds ratio = 0.79; 95% CI, 0.70-0.88). No significant association was found between higher density of GP contacts and urgent admissions. All groups registered longer than 5 years had significantly lower hospital costs, with the largest model-based reduction (-39.7%) in the group registered 10 to 15 years. Higher density of GP contacts was also associated with lower costs, with an adjusted relative reduction of 6% to 7% in total hospital costs. CONCLUSION: Long-standing continuity of care in general practice among adult patients is associated with reduced urgent hospital admissions and health care costs in the Netherlands. These findings highlight the potential value of sustained GP-patient relationships in improving hospital outcomes.