RT Journal Article SR Electronic T1 Risk of emergency admission while awaiting elective cholecystectomy JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP 662 OP 665 VO 169 IS 7 A1 Boris Sobolev A1 Dale Mercer A1 Peter Brown A1 Mark FitzGerald A1 Diederick Jalink A1 Ralph Shaw YR 2003 UL http://www.cmaj.ca/content/169/7/662.abstract AB Background: There is uncertainty regarding the frequency of adverse events while on a surgical waiting list. We assess the relationship between the duration of wait for cholecystectomy and the risk of emergency admission. Methods: We analyzed time to emergency admission in a group of 761 patients who underwent cholecystectomy after being seen in clinic for biliary colic and placed on waiting lists at 2 acute care centres in Ontario, from 1997 to 2000. Results: Emergency admissions due to worsening symptoms occurred in 51 patients (6.7%) waiting for elective cholecystectomy. The weekly rate of emergency admission was low during the first 19 weeks on the list, but increased almost by a factor of 3 after 20 weeks (rate ratio 2.7; 95% confidence interval 2.0–3.7). Relative to the first 4 weeks on the list, the rate was 1.6 times higher after 20 weeks, 2 times higher after 28 weeks and 7 times higher after 40 weeks. Interpretation: The probability that a patient on a waiting list will be admitted for emergency cholecystectomy consistently increases with the duration of wait, particularly after 20 weeks.