Continuity of Care and Risks of Hospitalization and Mortality in COPD: A Nationwide Cohort Study.

PURPOSE: Chronic obstructive pulmonary disease (COPD) is characterized by unpredictable patterns of exacerbations, making continuity of care (CoC) a critical component in disease management. CoC influences COPD exacerbation-related hospitalization and mortality. Therefore, we assessed the impact of CoC levels on subsequent hospital admissions and all-cause mortality among individuals with COPD. PATIENTS AND METHODS: This retrospective nationwide cohort study utilized National Health Insurance Service-Senior cohort data (2002-2019) and included 29,316 patients newly diagnosed with COPD. The primary exposure was longitudinal CoC level categorized as low (<0.7) or high (≥0.7). Alternative continuity indices (usual care provider, sequential continuity, and modified continuity indices) were also evaluated. Outcomes were COPD exacerbation-related hospitalization and all-cause mortality within 1 year of diagnosis. Cox proportional hazards models estimated hazard ratios (HRs), Kaplan-Meier curves, and cumulative incidence rates were used to assess outcomes, and the Log rank test was used for between-group comparisons. RESULTS: Low CoC level were associated with an increased risk of 3-year COPD exacerbation-related hospitalization (HR 1.63, 95% CI 1.45-1.83) and all-cause mortality (HR 1.25, 95% CI 1.11-1.40) compared with high CoC level. Intermediate (0.4-0.7) and low (<0.4) CoC level showed progressively increased hospitalizations (HR 1.61, 95% CI 1.40-1.86 vs HR 1.65, 95% CI 1.38-1.97), and mortality (HR 1.24, 95% CI 1.07-1.43 vs HR 1.26, 95% CI 1.05-1.51), respectively. These findings remained consistent across alternative continuity indices. Low CoC level were associated with an increased risk of emergency (HR 1.48, 95% CI 1.19-1.83) and general hospital admissions (HR 1.70, 95% CI 1.47-1.95). CONCLUSION: Lower CoC scores level consistently associated with higher risks of COPD hospitalization and all-cause mortality across multiple continuity indices. Subgroup and sensitivity analyses indicated that fragmented outpatient care increased adverse outcomes. Strengthening longitudinal patient-provider relationships may reduce preventable hospitalizations and premature deaths in patients with COPD.