Effectiveness of probiotic Bifidobacterium animalis DN-173010 in the management of constipation-predominant irritable bowel syndrome in black South African women

MSc (Dietetics), North-West University, Potchefstroom Campus, 2014Background - Irritable bowel syndrome (IBS) is a poorly understood functional gastrointestinal disorder and is a major cause of abdominal discomfort and gut dysfunction. IBS symptoms encompass abdominal pain, bloating, flatulence and irregular bowel movements such as constipation, diarrhoea and alternating bowels, bloating, flatulence and irregular bowel movements. Physiological studies have shown that manipulation of the intestinal microbiota by antibiotics, prebiotics or probiotics can affect intestinal functions in the pathogenesis of IBS. The probiotic concept suggests that supplementation of the intestinal microbiota with the right type and number of live microorganisms can improve gut microbiota composition and promote health in IBS sufferers. Aim - The aim of the main clinical trial is to determine whether ingestion of fermented milk containing Bifidobacterium animalis DN-173010 is associated with improved defecation frequency, stool consistency and quality of life in black South African females with constipation-predominant IBS (IBS-C). Methods - A pilot and process evaluation approach was employed during the current study to examine and understand the feasibility of implementing the study and to explore the facilitating implementation of the main clinical trial. Twenty black female participants, aged 18-60, with IBS-C were recruited from the practices of gastroenterologists, specialist physicians and medical doctors in Soweto. Participants fulfilling the Rome III criteria for IBS-C and inclusion criteria were randomized into two groups to participate in a 4-week, double blind, placebo controlled study. The placebo group received unflavoured sweetened, white base yoghurt and the intervention group received similar yoghurt with the probiotic, Bifidobacterium animalis DN-173010 [>3,4X10⁷ CFU/g]. Participants were required to record their bowel movements daily and IBS symptoms weekly in questionnaires during the four-week study period. Quality of life was assessed at baseline and at the end of the treatment period. Participants visited the study unit weekly to collect the placebo or probiotic study products and return the completed questionnaires during the study period. Results - Seventeen participants completed the study (eight intervention and nine placebo). There were not significant differences in IBS symptoms between the two groups, but differences were observed overtime within groups. The severity of abdominal pain score within both groups was statistically significant (p=0.004), and the number of days with pain was also statistically significant (p=0.00001). The frequency of normal stools reported was statistically significant different compared to all the other stool types (constipation and loose stools) throughout the four-week study period in both the intervention and placebo group. There was no significant difference in the quality of life between the intervention group compared to the placebo group. Conclusion - Process evaluation allows for the monitoring of a programme and corrections of problems as they occur. The intervention is feasible to implement, acceptable and safe to participants. The study indicates that consumption of the probiotic Bifidobacterium animalis DN-173010 for four weeks is not superior to the placebo in relieving IBS symptoms.Master