Comparison of the American Society of Anesthesiologists Physical Status classification with the Charlson score as predictors of survival after radical prostatectomy

Abstract

Objectives: To compare the American Society of Anesthesiologists Physical Status (ASA) classification with the Charlson score in the radical prostatectomy setting. The ASA classification is a widely accepted way to evaluate perioperative risk. At present, the Charlson score is probably the most frequently used comorbidity measure to predict long-term survival after radical prostatectomy.

Methods: A total of 444 consecutive patients were enrolled in this study. The ASA classification was obtained from the anesthesia chart, and the Charlson score was assigned based on conditions noted during the preoperative cardiopulmonary risk assessment or mentioned on the discharge document. Kaplan-Meier time-event curves and Mantel-Haenszel hazard ratios were estimated for comorbid (noncancer) and overall survival.

Results: After a mean follow-up of 5.9 years, both classifications were able to predict comorbid and overall survival in dose-response patterns. The ASA classification was superior in terms of a clearer discrimination of the survival curves (lower P values, higher hazard ratios). Both classifications identified a high-risk group (ASA 3 and Charlson score 2 or more), but only the ASA classification sufficiently defined a low-risk group (ASA 1).

Conclusions: In experienced hands, the ASA classification is a promising tool to improve the classification of prognostic comorbidity in the radical prostatectomy setting and may be used as an alternative to the Charlson score.