Abstract
Background: People with inflammatory bowel disease (IBD) are at higher risk of metabolic diseases that may respond to changes in diet and physical activity. Whether these lifestyle changes are possible and effective in IBD is unclear. This study aims to investigate the effectiveness of personalised diet and physical activity advice on metabolic disease risk factors in adults with inactive IBD.
Methods: A randomised controlled trial was conducted at three hospitals in New Zealand (NZ) from May 23 to August 24. Eligible participants (aged >18 years, body mass index (BMI) ≥ 25 kg/m2, low fibre intake (<25g/day), stable medical therapy, and could exercise) were randomised to one of two 6-month interventions: dietitian-delivered generic or personalised physical activity and heart-healthy diet advice. The primary outcome was body fat change and secondary outcomes included disease activity, faecal calprotectin, self-reported physical activity, and dietary intake (3-day food diaries). Multivariable regression models investigated between group differences adjusted for age, sex, and baseline values (significance p<0.05). Dietary intake and physical activity were adjusted for seasonality and disease activity. The study was approved by the NZ Health and Disability Ethics Committee (ref 2022 EXP 13602).
Results: A total of 64 participants were randomised and 51 (80%) completed the 6-month intervention and had complete datasets. Participants were median age 47 (LQ, UQ 37, 55), 59% female, 91% NZ European ethnicity, 61% had Crohn’s disease, 75% had faecal calprotectin < 100µg/g, 80% were non-smokers, and 81% on maintenance medical therapy including 44% on biologics. The intervention group had a non-significant decrease in fat mass (-188g; 95%CI: -1606, 1230) compared to the control group and statistically significant changes in dietary intake: increased fruit (0.5 serves/day; 95%CI: 0.1, 1.0) and dietary fibre (3.1 g/1000kcal/day; 95%CI: 1.1, 5.1), and reduced discretionary food and drink (-1.7 serves/day; 95%CI: -3.0, -0.3) and sodium (-911 mg/day; 95%CI: -1783, -40). Physical activity increased non-significantly by 188 total MET-mins/week (95%CI: -3336, 3711). Disease activity indices and faecal calprotectin did not significantly alter.
Conclusion: Dietitian-delivered personalised compared to generic advice, led to significant changes in dietary intake associated with reduced metabolic disease risk in patients with inactive IBD. However, the lack of significant changes in fat mass between groups is likely due to the absence of increased physical activity or reduced energy intake. Nonetheless, this study shows that adults with inactive IBD can make lifestyle changes without worsening disease activity.
Poster presentation.