Assessing the dose-response relationship between number of office-based visits and hospitalizations for patients with type II diabetes using generalized propensity score matching

Background: Whether inpatient services can be successfully substituted by office-based services has been debated for many decades, but the evidence is still inconclusive. This study aims to investigate the effect of office-based care on use and the expenditure for other healthcare services in patients with type II diabetes (T2D). Methods: A generalized propensity score matching approach was used on pooled Medical Expenditure Panel Survey (MEPS) data for 2000–2012 to explore a dose-response effect. Patients were matched by using a comprehensive set of variables selected following a standard model on access to care. Findings: Office-based care (up to 5 visits/year) acts as a substitute for other healthcare services and is associated with lower use and expenditure for inpatient, outpatient and emergency care. After five visits, office-based care becomes a complement to other services and is associated with increases in expenditure for T2D. Above 20 to 26 visits per year, depending on the healthcare service under consideration, the marginal effect of an additional office-based visit becomes non-statistically significant. Conclusions: Office-based visits appear to be an effective instrument to reduce use of inpatient care and other services, including outpatient and emergency-care, in patients with T2D without any increase in total healthcare expenditure.