Does Obesity Effect the Gastric Emptying or Small Bowel Transit Times of Capsule Endoscopy

Abstract

Purpose: Capsule endoscopy is increasingly used for the evaluation of the small bowel. However, there are no reported studies evaluating the impact of body mass index (BMI) on capsule transit times. This study evaluated the gastric emptying time (GET) and small bowel transit time (SBTT) of capsule endoscopy in overweight and obese patients. Methods: This retrospective study evaluated the medical records and capsule endoscopy reports of consecutive patients who underwent small bowel capsule endoscopy at a university gastroenterology practice. The medical records were reviewed to determine the Body Mass Index (BMI) of each patient. Patients with a BMI <25 were considered to be at a desired weight, between 25 and 29.9 were considered to be overweight, and ≥30 were considered to be obese. All patients in whom a BMI could be determined were included in the study. The capsule endoscopy reports of patients in whom a BMI was determined were evaluated for GET and SBTT. A database was created using Microsoft Excel. Statistical analysis was performed using t-test. The study was approved by the university IRB. Results: Medical records and capsule endoscopy reports of 186 patients were reviewed. Patients who were of desired weight (BMI<25) had an average GET of 59.88 minutes and SBTT of 289.37 minutes. Patients who were overweight (BMI 25–29.9) had an average GET of 60.65 minutes and SBTT of 248.97 minutes. Patients who were obese (BMI ≥30) had an average GET of 69.77 minutes and SBTT of 226.73 minutes. There was no statistically significant difference in the GET between the desired weight group compared to the overweight (p= 0.96) and obese groups (p= 0.66). There was also no statistically significant difference in the SBTT between the desired weight group and overweight group (p= 0.11). There was a statistically significant difference in the SBTT between the desired weight group and obese group (p= 0.02). Conclusions: There are no published reports on BMI and capsule endoscopy determined transit times. This study revealed that BMI has no impact on GET. However, BMI had a significant effect on the SBTT. The results suggest a patient's BMI influences small bowel transit, with obese patients having a more rapid SBTT. However, it is unclear if the increased transit time in obese patients impacts upon small bowel mucosal visualization. Additional investigations should be performed to determine if BMI influences capsule endoscopy results.