Long-term impact of Medicare managed care on patients treated for coronary artery disease

Abstract

Background: Planned health insurance reform promises and has started to cut reimbursement to Medicare managed care (MMC) plans. If such plans provide better care, adjusting for possible better health of their enrollees, then such reimbursement changes may have unforeseen quality consequences.

Objectives: To examine whether long-term follow-up outcomes of patients who receive intensive interventional care for coronary artery disease differed by Medicare plan type.

Research design: Patient-level postdischarge outcomes were multivariate adjusted logistic functions of a patient's insurance type at time of index admission. Data were retrospective secondary percutaneous coronary intervention data from Pennsylvania with 35,417 index admissions in 2004 to 2005 and in-state follow-up hospitalizations within 12 months and in-state death within 3 years of discharge.

Results: MMC insured patients had a consistently estimated 3-year survival benefit (relative risk of death 0.91; P value 0.003) compared with traditional Medicare traditional fee for service patients. Results were robust to propensity score stratification, subset analyses, and rich controls for observed confounders. Implausibly large associations (between an unmeasured confounder and both insurance status and outcomes) would have to be hypothesized to fully explain the observed survival benefit.

Conclusions: Among a large number of Pennsylvanian elderly patients, receiving a very common therapeutic procedure for highly prevalent disease, being insured with MMC was associated with a clinically meaningful long-term survival benefit. Impending health insurance reform that changes the relative attractiveness of MMC plans may have unintended consequences on outcome quality.