ObjectivesAcute cholecystitis is one of the most common surgical presentations in Australia and increases with age. Guidelines recommend early laparoscopic cholecystectomy (within 7 days), as it results in shorter length of stay, reduced costs and readmission rates. Despite this, there is a perception that early cholecystectomy may result in higher morbidity and conversion to open surgery in older patients. Our objective is to report the proportion of early versus delayed cholecystectomy in older patients in New South Wales (NSW), Australia, and to compare health outcomes and factors influencing variation.DesignThis is a retrospective population-based cohort study of all cholecystectomies for primary acute cholecystitis in NSW residents aged >50, between 2009 and 2019. The primary outcome was the proportion of early versus delayed cholecystectomy. We used multilevel multivariable logistic regression analyses adjusted for age, sex, comorbidities, insurance status, socio-economic status and hospital characteristics.ResultsA high rate (85%) of the 47,478 cholecystectomies in older patients were performed within 7 days of admission. Delayed surgery was associated with increasing age and comorbidity, male sex, Medicare-only insurance and surgery in low- or medium-volume centres. Early surgery was associated with shorter overall length of stay, fewer readmissions, less conversion to open surgery and lower bile duct injury rates.ConclusionA high proportion of adults with cholecystitis are undergoing early cholecystectomy in NSW. Our results support the efficacy of early cholecystectomy in older patients and identify potentially modifiable factors relevant to health care professionals and policymakers.