THE BOSTON AIDS SURVIVAL SCORE (BASS) - A MULTIDIMENSIONAL AIDS SEVERITY INSTRUMENT

Objectives. This study developed a new acquired immunodeficiency syndr ome (AIDS) severity system by including diagnostic, physiological, fun ctional, and sociodemographic factors predictive of survival. Methods. Three-hundred five persons with AIDS in Boston were interviewed; thei r medical records were reviewed and vital status ascertained. Results. Overall median (+/-SD) survival for the cohort from the first intervi ew until death was 560 +/- 14.4 days. The best model for predicting su rvival, the Boston AIDS Survival Score, included-the Justice score (st age 2 relative hazard [RH] = 1.25, 95% confidence interval [CI] = 0.80 , 1.96; stage 3 RH = 1.76, 95% CI = 1.15, 2.70), a newly developed opp ortunistic disease; score (Boston opportunistic Disease Survival Score ; stage 2 RH = 1.35, 95% CI = 0.90, 2.02; stage 3 RH = 2.10, 95% CI = 1.38, 3.18), and measures of activities of daily living (any intermedi ate limitations, RH = 1.84, 95% CI = 1.05, 3.21; any basic limitations , RH = 2.60, 95% CI = 1.44, 4.69). This model had substantially greate r predictive power (R-2 = .17, C statistic = .68) than the Justice sco re alone (R-2 = .09, C statistic = .61). Conclusions. Incorporating da ta on clinically important events and functional: status into a physio logically based system can-improve the prediction of survival with AID S.