Influence of shunt surgery on healthcare expenditures of elderly fee-for-service Medicare beneficiaries with hydrocephalus.

Object: The goal in this study was to determine the percentage of patients with hydrocephalus who were treated with shunt surgery and to assess Medicare expenditures for those with and without shunt surgery.

Methods: Retrospective cost analyses were performed using the Standard Analytic Files of paid claims for beneficiaries enrolled in both Parts A (Inpatient) and B (Outpatient) of the Medicare program for 1997 through 2001. The main outcome measures were 5-year total payments and 5-year payments for separate types of service; for example, acute hospital (inpatient and outpatient), skilled nursing facility, home health, and physician/supplier services.

Results: Of 1441 patients with hydrocephalus, 25.1% underwent shunt surgery during the study period. The effect of a shunt procedure on 5-year Medicare expenditures is a cost difference of $25,477 (p < 0.0001) less per patient, which is equal to a potential -$184.3 million difference in 5-year Medicare expenditures. The following three factors had a negative association with whether shunt surgery was performed: (1) age 80 to 84 years (odds ratio [OR] 0.619, confidence interval [CI] 0.390-0.984); (2) age 85 years or older (OR 0.201, CI 0.110-0.366); and (3) African-American race (OR 0.506, CI 0.295-0.869). The effect of age on the likelihood of shunt surgery persisted after adjusting for the propensity to die score.

Conclusions: Medicare expenditures for patients with hydrocephalus treated with shunt surgery are significantly lower than expenditures for untreated patients. Research to improve the diagnosis and treatment of hydrocephalus has the potential to improve outcomes and reduce health care expenditures further.