Obesity Not Necessary, Risk of Symptomatic Cholelithiasis Increases as a Function of BMI

Introduction: Obesity is a well-established risk factor for cholelithiasis. But most of the studies have actually tried to establish the risk of cholelithiasis in overweight and obese people. Very few studies have addressed the issue of cholelithiasis in patients with otherwise normal Body Mass Index (BMI). In this study we have tried to establish if there is any relationship between increasing BMI and cholelithiasis. Aim: To establish a relationship between increasing BMI and risk of cholelithiasis. Materials and Methods: Retrospective analysis was carried out after doing a prospective pilot study. Ten years data of patients admitted to surgery ward with complaints of pain abdomen was reviewed. Patients with cholelithiasis were segregated as cases and patients with some other diagnosis were selected as controls. Patients with incidental diagnosis of cholelithiasis were excluded. Appropriate analytical tools were used to draw the results using SPSS (c) 20. Results: Over 11,000 patients data was reviewed and 7,182 patients were selected for inclusion into the study. Major exclusion was due to incomplete availability of data. Cholelithiasis group had 2,872 patients and rest of the patients served as controls against them. Female patients outnumbered their male counterparts in cholelithiasis group. Mean age of the gallstone patients was 37.09 years, almost 2 years younger than their controls. Mean BMI of all patients was 23.55 kg/m(2) and in cholelithiasis and control group was 24.93 and 22.62, respectively (df=1, F>1635.395, p<0.001). Gender specific comparison also yielded a significant difference df=3, F=547.238, p<0.001). The difference in the way the patients were distributed among the ethnic groups (Nepalis, Bhutias, Lepchas and others) was also significant (df=3, F=34.234, p<0.001). Most important outcome was that the majority of the patients in the cholelithiasis group were within the normal BMI range. Conclusion: We concluded that it's not only the overweight or obese patients who develop symptomatic cholelithiasis but also the individuals with normal BMI. The risk of symptomatic cholelithiasis increases with every increase in BMI. Risk of symptomatic cholelithiasis also increases in women and as the age advances.