Gallstone disease : Population based studies on risk factors, symptomatology and complications

Abstract: Background & aims: Gallstone disease is common, costly and its complications are sometimes life threatening. The aim of this thesis is to determine the prevalence and incidence in relation to putative risk factors in the general population. Furthermore, to identify individuals with asymptomatic gallstones who are at risk of developing complications and, finally, to identify those who are at risk of an unsatisfactory outcome after cholecystectomy.Material & methods: A sample of the adult (35-85 y.) general population was screened with ultrasound examination, blood tests and a questionnaire regarding digestive symptoms, life-style and quality of life. After excluding 115 subjects, who previously had a cholecystectomy, 739 participated. The examination was repeated after a minimum of five years. The individuals who were shown to have gallstones were followed in order to identify risk factors for developing complications. 200 consecutive symptomatic patients were operated with cholecystectomy on defined indications. They completed a questionnaire regarding digestive symptoms, life-style and quality of life before and three and twelve months after surgery.Results: The crude prevalence of gallstone disease was 17.2 % for women and 12.4% for men. It increased with age and was higher among women. Symptoms did not differ between subjects with and without gallstones, but those previously operated with cholecystectomy did worse both regarding symptoms and quality of life. The estimated crude annual gallstone incidence was 1.5%. This increased with age, but did not differ between the sexes. Gallstone development was positively related to elevated blood lipids and negatively related to alcohol consumption. Fourteen of 120 subjects with gallstones at the primary screening developed a complication demanding treatment during a follow-up interval of 87 (3-146) months. In the patient series operated on strict indications, 91.3 % of those who had reported typical gallstone related pain preoperatively, experienced total or partial pain relief 3 months postoperatively. With atypical pain preoperatively, the corresponding figure was 77.1 %. The findings 12 months postoperatively were similar. In the logistic regression analysis, young age, frequency of pain episodes, atypical pain, specific food intolerance and disturbing abdominal gas were positively related to the frequency of abdominal pain 12 months after surgery.Conclusion: The prevalence of gallstones was positively related to age and female gender. Previous cholecystectomy was associated with more symptoms and worse quality of life. The annual gallstone incidence of 1.5 % was high in comparison with other studies, but our population was older. In general, neither prevalent nor incident gallstones in the general population were associated with specific symptoms. The cumulative risk of developing a complication to gallstone disease during a 5-year followup interval was 7.6 % with no tendency to level off.Patients with typical pain had a better outcome after cholecystectomy. Young age, atypical pain and frequent pain episodes before surgery were major risk factors for a worse outcome in terms of persistent pain.