Commentary: the rising tide of cholecystectomy for biliary dyskinesia – author's reply

Abstract

Bj€orck and colleagues raise an important point by discussing the potential impact of obesity on gall-bladder structure and/or function, which could contribute to increased cholecystectomy rates. 2 Administrative data banks such as the National In-patient Sample cannot directly address this interesting point. However, several findings argue against obesity as the primary culprit. First, obesity rates in children and adolescents are comparable for boys and girls, while cholecystectomies are preferentially performed in girls and women. Second, time trends in the United States show a relatively stable obesity rate with only minor increases for boys and no significant changes for girls between 1999 and 2010. The data stand in stark contrast to cholecystectomies for biliary dyskinesia, which increased more than sixfold within the same time, again mostly for girls. Third, large epidemiological studies have demonstrated that obesity is a major risk factor for gallstone formation and cholecystectomy in men and women. However, admission rates for acute complications of cholelithiasis decreased between 1997 and 2010, while obesity rates unfortunately did not decline, remaining well above 30% for women and men within the United States. Lastly, if obesity indeed caused clinically relevant gallbladder dysfunction, similar trends should be seen in Sweden where the prevalence of overweight children and adults is admittedly lower than in the United States, but has been climbing within the last decade. Yet, the data presented by Bj€orck and colleagues show a stable and low number of cholecystectomies for presumed functional gall-bladder disorders, thus lending additional support to the conclusion that socio-economic factors play an important role in decisions about gall-bladder surgery.