Influence of general health and degree of surgical insult on long-term survival.

Abstract

This study investigated the relationship of American Society of Anesthesiologists Physical Status (ASA-PS) grade and degree of surgical insult to long-term postoperative survival. National death records to June 2007 were matched against records of patients undergoing elective surgery between January 1997 and December 2001. Stratified survival analysis was performed to allow baseline hazard functions to vary among four patient groups (15-64 years with no malignancy, at least 65 years with no malignancy, 15-64 years with malignancy and at least 65 years with malignancy). Of 8134 patients, 6185 (76.0 per cent) were alive after a median follow-up of 7.1 (range 0-10.5) years. The overall mortality rate was 3.62 (95 per cent confidence interval (c.i.) 3.46 to 3.78) per 100 person-years. The 10-year probability of survival was significantly higher in ASA-PS I or II for minor or intermediate surgery (90.7 (89.1 to 92.1) per cent) than in ASA-PS I or II for major or complex major surgery (79.6 (77.5 to 81.6) per cent), ASA-PS III or IV for minor or intermediate surgery (41.2 (36.2 to 46.7) per cent) and ASA-PS III or IV for major or complex major surgery (44.6 (41.4 to 47.7) per cent) (P < 0.001). Priority of admission modified survival probabilities. Adjusted survival probabilities were lowest in the elderly with malignancy. ASA-PS grade has a more significant and persistent effect on long-term survival than degree of surgical insult.