Impact of continuity of care on preventable hospitalization of patients with type 2 diabetes: A nationwide Korean cohort study, 2002-10

Objective: To determine whether patients with greater continuity of care (COC) have fewer preventable hospitalizations.Design: We conducted a cohort study using a stratified random sample of Korean National Health Insurance enrollees from 2002 to 2010. The COC index was calculated for each year post-diagnosis based on ambulatory care visits. We performed a recurrent event survival analysis via Cox proportional hazard regression analysis of preventable hospitalizations.Study participants: A total of 5163 patients newly diagnosed with type 2 diabetes mellitus in 2003-6 and receiving oral hypoglycemic medication.Main outcome measure: Preventable hospitalization.Results: Of 5163 eligible participants, 6.4% (n = 328) experienced a preventable hospitalization during the study period. The adjusted hazard ratio (HR) was 8.69 (95% CI, 2.62-28.83) for subjects with a COC score of 0.00-0.19, 7.03 (95% CI, 4.50-10.96) for those with a score of 0.20-0.39, 3.01 (95% CI, 2.06-4.40) for those with a score of 0.40-059, 4.42 (95% CI, 3.04-6.42) for those with a score of 0.60-0.79 and 5.82 (95% CI, 3.87-8.75) for those with a score of 0.80-0.99. The difference in cumulative incidence of preventable hospitalizations in patients with COC scores of 0.00-0.19 relative to those with COC scores of 1.00 was the greatest, at 0.97% points.Conclusions: Greater COC was associated with fewer preventable hospitalizations in subjects with type 2 diabetes.