Dr. Lee L. Swanstrom (Portland, OR): Dr. Franceschilli and her colleagues present an interesting study on the prevalence and effect of bariatric surgery on the incidence of defaecatory disorders (DD)—namely constipation or faecal incontinence. Both problems were quantified using validated scoring systems although it should be mentioned that neither system was specifically validated in the morbidly obese population.
Two populations were studied: 143 patients waiting for bariatric surgery and 44 patients who had bariatric surgery and had follow-up questionnaires to determine the effect on the surgery on their problem. They found, as have many others, that DD is very prevalent in the morbidly obese (61% in their population with one third constipated and about one third with faecal incontinence). The second group showed little effect on constipation but did show improvement in faecal incontinence; a change which correlated with the amount of weight lost. The report is weakened by the fact that we are not given a clue as to why the patients of either group had DD before surgery—how many had diarrhea? Both to start with and after surgery.
How valid is the FISI score for the morbidly obese? Is it possible that their complaints of “faecal soilage” are more related to mechanical and ergonomic issues than to a true DD?
The authors declare that faecal incontinence is progressively improved with weight loss—but is it not equally possible that the improvement seen is due to a change in their eating habits and that better eating leads both to weight loss and to better bowel function?
In light of their results, I might suggest to the authors that a better title for their report is “Fecal incontinence is improved following gastric sleeve resection.”
Dr. Pierapolo Sileri: Prof. Swanstrom, thank you for your questions and comment.
Regarding the first question, in our study, we did not include patients with history of chronic diarrhea, inflammatory bowel disease, major non-obstetric anal sphincter trauma, or previous anorectal surgery (other than uncomplicated hemorrhoidectomy).
Fecal Incontinence Severity Index is based on a type-by-frequency matrix with four types of leakage (gas, mucus, liquid stool, and solid stool) and five frequencies (one to three times per month, once per week, twice per week, once per day, twice or more per day). We believe that faecal incontinence is related to the increased intra-abdominal pressure, diabetes, nerve conduction damage and generalized weakness and sagging of the pelvic floor. In our study, FI progressively improved with weight loss but we agree that the improvement seen might be also due to a change in eating habits and a better eating.
This study aims at assessing the effect of morbid obesity on DDs and to evaluate FI and constipation pattern in patients who underwent sleeve gastrectomy thus excluding other bariatric procedures such as gastric bypass which may lead to bowel symptoms as diarrhoea due to malabsorption of micro- and macronutrients and changes in bacterial flora of the bowel. Sleeve gastrectomy counts the major number of bariatric procedure in our facility and, as a restrictive procedure, does not change the physiology of the bowel thus with neglectable effects on defaecation.