Cost and quality impacts of treatment loci for type 2 diabetes patients with moderate disease severity: Hospital- vs. GP-basedmonitoring

Objectives:This study investigates cost and quality implications of pushing regular monitoring of moderateseverity type 2 diabetes (T2D) patients away from specialized hospital clinics into general practice(GP).Methods:152,630 hospital- and 21,361 GP-monitored T2D patients with moderate disease severity werealgorithmically identified in Danish administrative databases in 2016. Total annual healthcare costis decomposed into GP, medication, nonhospital-specialist, hospital outpatient and inpatient costs.Emergency hospitalizations are used to proxy for quality of care. Cost and quality impacts oftreatment loci are assessed using an instrumental variable (IV) analysis. A wide range of patientconfounders are used to reduce selection bias, with distance to nearest hospital diabetes clinic usedas an instrument to control for remaining endogeneity of treatment locus. Two-part models areused for zero-inflated outcomes.Results:Hospital monitoring is associated with higher total annual healthcare costs (64.0%, p<0.05). Wefind no difference in emergency hospitalizations from our IV analysis. OLS regression modelsindicate only slightly lower rates of emergency hospitalizations for hospital-monitored patients.Conclusion:For type 2 diabetes patients with moderate disease severity, IV analysis controlling for treatmentlocus endogeneity bias identifies an expected efficiency improvement (average cost reductionwithout reduction of quality) of moving regular disease management from hospital-based settingto primary care.