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.