| Introduction: Considering the link between vitamin A deficiency and disease activity in ulcerative colitis (UC)
and also the association between dietary intake of vitamin A and gastrointestinal symptoms in these patients,
this study aimed to investigate the effect of vitamin A supplementation on disease activity in patients with UC.
Method: In the present double-blind randomized controlled clinical trial, one hundred and fifty patients with
Mayo score of 6–12 were randomly assigned to receive 25,000 IU/day vitamin A supplements or placebo for two
months. The disease activity was calculated by the Mayo clinic score. Within groups and between groups
comparisons were performed using paired sample t-test and one-way ANCOVA respectively. For measuring the
treatment effect, the response ratio and number needed to treat (NNT) was calculated for the rate of clinical
response and mucosal healing.
Results: One hundred and forty three patients completed the study. After two months of supplementation, significant
decreases in Mayo clinic score (p < 0.001) and subscores (p < 0.001) was observed in the intervention
group. There were significant differences between the two groups regarding Mayo clinic score and subscores
after adjusting for age, sex, BMI, disease duration and baseline values (P < 0.05). Moreover, there were significant
differences between two groups regarding clinical response ratio (P < 0.001) and mucosal healing ratio
(P < 0.001). The NNT [95%CI] values for the clinical response was 3 [2–40] and for the mucosal healing was 5
[2.90–10.4].
Conclusion: Although according to the results, daily dose of 25,000 IU vitamin A had positive clinical and endoscopic
effects, considering the limitations, further studies with longer duration and larger sample size and
considering dietary intake are needed to confirm these preliminary results. |