The Cost of Transferring Dialysis Care From the Employer-Based Market to Medicare

This cohort study investigates the frequency and characteristics of patients with end-stage kidney disease receiving dialysis who prematurely transition from their employer-based group health plan to Medicare.


Introduction
Many patients with end-stage kidney disease (ESKD) retain their employer-based group health plan (EGHP) when they start dialysis. 1 Patients with EGHPs may obtain Medicare as a secondary payer, but the EGHP remains the primary payer for 30 months during what is known as a coordination period. 2 If patients prematurely drop their EGHPs (eg, if they become unemployed or if their employers or payers stop offering favorable plans), Medicare becomes the primary payer, which frees the EGHPs of their financial obligations. This cohort study investigated the frequency of premature switches, the characteristics of patients switching early, and the resulting Medicare spending. Premature switches to Medicare (ie, before the end of the EGHP coordination period) were identified, and the extra months of Medicare use were totaled. Patients were stratified into hospitalization probability quartiles to proxy for severity of illness. To estimate hospitalization probabilities, regression coefficients were applied from a multivariable logistic regression in adults aged 62 or younger who started dialysis with fee-for-service Medicare as the primary payer. The dependent variable was whether the patient was hospitalized in a 12-month period, and independent variables were patient characteristics and comorbidities, facility characteristics, and zip code sociodemographics (eTable in the Supplement).

Methods
A Cox proportional hazards model was used to estimate the likelihood of premature switching by hospitalization probability quartile. Ordinary least squares were used to compare total Medicare spending (as the primary or secondary payer) when switching prematurely, switching at the coordination period, and switching after the coordination period or never. Statistical significance was set at P = .05, and tests were 2-sided. Statistical analysis was performed using SAS version 9.4 (SAS Institute) and Stata version 14.0, MP edition (StataCorp).  Table 1). Patients with a higher hospitalization risk were more likely to switch from their EGHP to Medicare prematurely. For example, the third quartile of illness severity was 49% (95% CI, 45%-53%) more likely to switch relative to the quartile that included the patients least likely to be hospitalized within 12 months ( Table 2).

Discussion
Nearly one-third of adults 62 years or younger who began dialysis with an EGHP switched to Medicare prematurely, resulting in more than $3 billion of additional Medicare spending from 2007  Abbreviations: HR, hazard ratio; NA, not applicable.
a Quartiles for 12-month probability of hospitalization. The probability of hospitalization among patients with an employerbased group health plan was estimated via a Cox proportional hazards model, modeling the association between premature switching from an employer-based group health plan to Medicare and probability of being hospitalized in 12 months. Estimated probabilities were obtained using multivariable logistic regression in patients with traditional Medicare.
Data System. The interpretation and reporting of these data are the responsibility of the author and in no way should be seen as an official policy or interpretation of the US government.