Effect of bee food supplement propolis on food intake, severity of disease and quality of life in patients with irritable bowel syndrome (based on ROME IV criteria): a randomized double-blind clinical trial

Abstract

Background: Due to the high prevalence of irritable bowel syndrome (IBS), a chronic and recurrent gastrointestinal disease, and the fact that no specific drug has been approved for the treatment of IBS, it seems that the design of adjunctive therapy programs to improve the clinical condition of these patients are required. With the emphasis on the role of inflammation in the pathogenesis of this disease, a new perspective emerged on the role of antioxidant and anti-inflammatory compounds in IBS treatment. Among these substances, propolis is a natural resin prepared by bees from the petals and buds of plants. Studies have shown that propolis has biological properties including antioxidant, anti-inflammatory, prebiotic, antibacterial and immune modulating. Considering the effects of propolis, it seems that this substance can be effective in improving the clinical condition of patients with IBS. Since no human studies have been performed to evaluate the effects of propolis supplementation on IBS, the present study was designed for the first time to investigate the effects of propolis supplementation on the severity, quality of life and dietary intakes in patients with IBS. Methods: In this clinical trial study, 56 patients with IBS diagnosed by Rome IV criteria were assigned for 6 weeks randomly to the intervention and control groups (28 patients in each group). At the baseline and the endpoint of the study, anthropometric indices, level of physical activity, anxiety status and quality of life, as well as IBS severity before and after supplementation were assessed. Dietary intakes were also evaluated in the baseline, middle and the endpoint of the study. Patients in the intervention group received two tablets of propolis (450 mg) daily and in the control group they received the same amount of placebo for 6 weeks. Independent t-test, paired t-test, Mann-Whitney U test, Wilcoxon, Fisher's exact test, repeated measures analysis of variance and logistic regression test were used for analyzing the data. To adjust the effect of confounders, covariance analysis was used. Results: The results of this study showed that after modulating the effect of potential confounders, propolis supplementation increased the chance of improving IBS severity by 6.22 (with a confidence interval of: 1.33 - 1.14 and P = 0.035). A significant abdominal pain improvement, anxiety state, and bowel habits dissatisfaction reduction was observed within- and between-group differences in propolis group compared to the placebo group (P = 0.040, P = 0.035, P = 0.029, retrospectively). The overall score of quality of life and its domains in the propolis group was statistically significant, but in comparison between the two groups, this difference was not significant. Also, regards to the food intakes and anthropometric indices, there were no significant differences between and within the two study groups. Conclusions: This study illustrated that propolis supplementation could be used as adjunctive therapy in IBS disease to reduce abdominal pain and modulate the anxiety state of patients.