Total and Segmental Colonic Transit Time in Patients with Constipation Attending in Dhaka Medical College Hospital: A Case Control Study.

Constipation is a regular medical sickness all over the world. Primary constipation may by normal transit constipation, slow transit constipation and fecal evacuation disorder. Categorization into these types is important for subsequent management. Among the methods of measurement of colonic transit time radiopaque marker study is simple and easy to perform. This case control observational study was conducted in the department of Gastroenterology, Dhaka Medical College and Hospital, Bangladesh from March 2018 to March 2019 to measure the colonic transit time of patient of constipation and to compare it with healthy control. Constipation can be sub-classified with colonic transit time. Patient of chronic constipation were divided into functional constipation and constipation predominant irritable bowel syndrome according to symptoms based diagnostic criteria. Patients with constipation underwent routine investigation including colonoscopy to exclude organic disease. Two gelatin capsules (each containing 10 radio-opaque markers) were ingested by patient at 0, 12 and 24 hours. At 36 hours from the time of taking of first dose of markers abdominal radiograph was taken to calculate retained marker and colonic transit time in each segment of colon. Colonic transit time calculated using, Colonic transit time (or segmental transit time) = 12/20 × (n) hours, where n is the sum of the markers on the X-ray film (or in the delineated segment) this formula. Healthy control undergone same procedure. Comparison of results was done using paired and unpaired 't'-test. In this study with this method, mean total Colonic transit time of healthy participant found 9.98 hours (min 1.8, max 18) and patient with constipation is 11.5 hours (min 0.0 hour, max 23.4 hour). The difference is not significant. Total colonic transit time in "slow transit time" patients is 22 hours (min 20, max 23.4) and 8.87 hours (min 0, max 16.2) in normal transit time patients. Segmental colonic transit of case group are right segment 4.7 hours (min 0, max 3.6), left segment 3.1 hour (min 0, max 10.2) and rectosigmoid segment 3.8 hour (min 0, max 14). The corresponding value in healthy control are 3.3 hour (0.6 min, max 7.2), 2.2 hour (min 0.6, max 4.8) and 4.3 hour (min 0, max 12) respectively. In real life colonic transit time can not be 0 hour, but with this method it can be 0, if the number retained marker is 0 then calculated colonic transit time can be 0 hour. No significant difference found between male and female, smoker and non-smoker of both groups.