title: Increased Risk of Depressive Disorder following Cholecystectomy for Gallstones.
abstract: BACKGROUND
  Prior studies indicate a possible association between depression and cholecystectomy, but no study has compared the risk of post-operative depressive disorders (DD) after cholecystectomy. This retrospective follow-up study aimed to examine the relationship between cholecystectomy and the risk of DD in patients with gallstones in a population-based database.
  
  
  METHODS
  Using ambulatory care data from the Longitudinal Health Insurance Database 2000, 6755 patients who received a first-time principal diagnosis of gallstones at the emergency room (ER) were identified. Among them, 1197 underwent cholecystectomy. Each patient was then individually followed-up for two years to identify those who were later diagnosed with DD. Cox proportional hazards regressions were performed to estimate the risk of developing DD between patients with gallstone who did and those who did not undergo cholecystectomy.
  
  
  RESULTS
  Of 6755 patients with gallstones, 173 (2.56%) were diagnosed with DD during the two-year follow-up. Among patients who did and those who did not undergo cholecystectomy, 3.51% and 2.36% later developed depressive disorder, respectively. After adjusting for the patient's sex, age and geographic location, the hazard ratio (HR) of DD within two years of gallstone diagnosis was 1.43 (95% CI, 1.02-2.04) for patients who underwent cholecystectomy compared to those who did not. Females, but not males, had a higher the adjusted HR of DD (1.61; 95% CI, 1.08-2.41) for patients who underwent cholecystectomy compared to those who did not.
  
  
  CONCLUSIONS
  There is an association between cholecystectomy and subsequent risk of DD among females, but not in males.
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Cathay General Hospital, Taipei, Taiwan; School of Health Care Administration, Taipei Medical University, Taipei, Taiwan.
authors.forename: Ming-Chieh
authors.initials: MC
authors.lastname: Tsai
authors.affiliation: Department of Cosmetic Applications and Management, Mackay Junior College of Medicine, Nursing, and Management, Taipei, Taiwan; Department of Thoracic Surgery, MacKay Memorial Hospital, Taipei, Taiwan.
authors.forename: Chao-Hung
authors.initials: CH
authors.lastname: Chen
authors.affiliation: Sleep Research Center, Taipei Medical University Hospital, Taipei, Taiwan; Department of Psychiatry, Taipei Medical University Hospital, Taipei, Taiwan.
authors.forename: Hsin-Chien
authors.initials: HC
authors.lastname: Lee
authors.affiliation: School of Health Care Administration, Taipei Medical University, Taipei, Taiwan; Sleep Research Center, Taipei Medical University Hospital, Taipei, Taiwan.
authors.forename: Herng-Ching
authors.initials: HC
authors.lastname: Lin
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan.
authors.forename: Cha-Ze
authors.initials: CZ
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D002763:Cholecystectomy / Q000009:adverse effects*; D003866:Depressive Disorder / Q000453:epidemiology* / Q000209:etiology*; D005260:Female; D042882:Gallstones / Q000150:complications* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012306:Risk