Are aggressive treatment strategies less cost-effective for older patients? The case of ventilator support and aggressive care for patients with acute respiratory failure.

OBJECTIVES: A common assumption is that life-sustaining treatments are much less cost-effective for older patients than for younger patients. We estimated the incremental cost-effectiveness of providing mechanical ventilation and intensive care for patients of various ages who had acute respiratory failure.
DESIGN: Retrospective analysis of data on acute respiratory failure from Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments (SUPPORT).
SETTING: Acute hospital. PARTICIPANTS: 1,005 with acute respiratory failure; 963 received ventilator support and 42 had ventilator support withheld. MEASUREMENTS: We studied 1,005 patients enrolled in a five-center study of seriously ill patients (SUPPORT) with acute respiratory failure (pneumonia or acute respiratory distress syndrome and an Acute Physiology Score > or = 10) requiring ventilator support. For cost-effectiveness analyses, we estimated life expectancy based on long-term follow-up of SUPPORT patients and estimated utilities (quality-of-life weights) using time-tradeoff questions. We used hospital fiscal data and Medicare data to estimate healthcare costs. We divided patients into three age groups (< 65, 65-74, and > or = 75 years); for each age group, we performed separate analyses for patients with a < or = 50% probability of surviving at least 2 months (high-risk group) and those with a > 50% probability of surviving at least 2 months (low-risk group).
RESULTS: Of the 963 patients who received ventilator support, 44% were female; 48% survived 6 months; and the median (25th, 75th percentile) age was 63 (46, 75) years. For the 42 patients for whom ventilator support was withheld, the median survival was 3 days. For low-risk patients (> 50% estimated 2-month survival), the incremental cost (1998 dollars) per quality-adjusted life-year (QALY) saved by providing ventilator support and aggressive care increased across the three age groups ($32,000 for patients age < 65, $44,000 for those age 65-74, and $46,000 for those age > or = 75). For high-risk patients, the incremental cost-effectiveness was much less favorable and was least favorable for younger patients ($130,000 for patients age < 65, $100,000 for those age 65-74, and $96,000 for those age > or = 75). When we varied our assumptions from 50% to 200% of our baseline estimates in sensitivity analyses, results were most sensitive to the costs of the index hospitalization.
CONCLUSIONS: For patients with relatively good short-term prognoses, we found that ventilator support and aggressive care were economically worthwhile, even for patients 75 years and older. For patients with poor short-term prognoses, ventilator support and aggressive care were much less cost-effective for adults of all ages.