Medicare's new restrictions on rehabilitation admissions: impact on the elderly.

Objective: To measure the impact of Medicare's "75% rule" on readmission and death rates in elderly patients affected by the rule.

Design: Retrospective study of two cohorts, both aged > or =65, discharged from a single medical center, from acute care with diagnoses excluded by the 75% rule. Group 1 (n = 4107) represented discharges in the year before the rule's enforcement and group 2 (n = 3893) for the rule's inaugural year. Logistic regression was used to compare mortality and readmission rates, and Cox regression was used for time to event data.

Results: Overall, patients were readmitted and died relatively sooner in group 2. Mortality and readmission rates were significantly associated with an age and group interaction, with higher rates in group 2 among older patients. The increase in readmissions was greatest for pain syndromes (from 33 to 55%). In patients older than 85 with orthopedic diagnoses, the mortality rate increased from 25 to 54%. Cardiac patients died and were readmitted sooner in group 2 and pulmonary patients also died sooner. The largest subgroups, miscellaneous and lower limb joint replacement/osteoarthritis, did not show significant differences in readmission rates and mortality.

Conclusions: Restricting access to inpatient rehabilitation on the basis of diagnosis alone is associated with increased readmission and mortality, particularly in the very old. Comprehensive, evidence-based guidelines are needed to allocate rehabilitation services to those who need them most.