Objectives: This study aimed to examine the relationship between diet and cholecystectomy risk, using three approaches, in a large French cohort.
Methods: In a prospective cohort study in French women who completed a food-frequency questionnaire at baseline, we analyzed diet with three approaches: food groups, dietary patterns obtained by factor analysis, and the Mediterranean diet score. The primary outcome was cholecystectomy. We used Cox proportional hazards regression to assess the relationship between diet and cholecystectomy risk, adjusting for the main potential confounders.
Results: During 1,033,955 person years of follow-up, we identified 2,778 incident cases of cholecystectomy. Higher intakes of legumes, fruit, vegetable oil, and wholemeal bread were associated with decreased cholecystectomy risk. Two dietary patterns were identified by factor analysis: "Western" (essentially processed meat, pizza, pies, high-alcohol beverages, French fries, sandwiches…) and "Mediterranean" (essentially fruits, vegetables, seafood, and olive oil). The "Mediterranean" pattern was inversely associated with cholecystectomy risk in the subgroup of postmenopausal women who ever used menopausal hormone therapy (hazard ratio for quartile 4 vs. 1=0.79, 95% confidence interval (CI): 0.65-0.95; P for linear trend=0.008). High adherence to the Mediterranean diet was associated with decreased risk of cholecystectomy (hazard ratio for a 6-9 score vs. 0-3=0.89, 95% CI: 0.80-0.99; P for linear trend=0.02).
Conclusions: Adherence to a diet rich in fruit, vegetables, legumes, and olive oil was associated with a reduction in cholecystectomy risk in French women. Further studies in different settings are requested.