Is survival better at hospitals with higher "end-of-life" treatment intensity?

BACKGROUND

Concern regarding wide variations in spending and intensive care unit use for patients at the end of life hinges on the assumption that such treatment offers little or no survival benefit.

OBJECTIVE

To explore the relationship between hospital "end-of-life" (EOL) treatment intensity and postadmission survival.

RESEARCH DESIGN

Retrospective cohort analysis of Pennsylvania Health Care Cost Containment Council discharge data April 2001 to March 2005 linked to vital statistics data through September 2005 using hospital-level correlation, admission-level marginal structural logistic regression, and pooled logistic regression to approximate a Cox survival model.

SUBJECTS

A total of 1,021,909 patients > or =65 years old, incurring 2,216,815 admissions in 169 Pennsylvania acute care hospitals.

MEASURES

EOL treatment intensity (a summed index of standardized intensive care unit and life-sustaining treatment use among patients with a high predicted probability of dying [PPD] at admission) and 30- and 180-day postadmission mortality.

RESULTS

There was a nonlinear negative relationship between hospital EOL treatment intensity and 30-day mortality among all admissions, although patients with higher PPD derived the greatest benefit. Compared with admission at an average intensity hospital, admission to a hospital 1 standard deviation below versus 1 standard deviation above average intensity resulted in an adjusted odds ratio of mortality for admissions at low PPD of 1.06 (1.04-1.08) versus 0.97 (0.96-0.99); average PPD: 1.06 (1.04-1.09) versus 0.97 (0.96-0.99); and high PPD: 1.09 (1.07-1.11) versus 0.97 (0.95-0.99), respectively. By 180 days, the benefits to intensity attenuated (low PPD: 1.03 [1.01-1.04] vs. 1.00 [0.98-1.01]; average PPD: 1.03 [1.02-1.05] vs. 1.00 [0.98-1.01]; and high PPD: 1.06 [1.04-1.09] vs. 1.00 [0.98-1.02]), respectively.

CONCLUSIONS

Admission to higher EOL treatment intensity hospitals is associated with small gains in postadmission survival. The marginal returns to intensity diminish for admission to hospitals above average EOL treatment intensity and wane with time.