The elderly group was more likely to have an American Society of Anesthesiologists score of 3 or greater ( 62 % vs 23 % , P < .001 ) , higher serum creatinine ( 103 vs 74 mol/L , P < .001 ) , and more-severe ACC ( moderate ACC ( 62 % vs 50 % , P = .05 ) , gangrenous cholecystitis ( 38 % vs 15 % , P = .001 ) ) on preoperative imaging and confirmed intraoperatively .