(B-218) The Inclusion of Dietary Data in Real-World Gastroenterology Studies: Insights from a Literature Review on Crohn’s Disease

Background: In gastroenterology (GI)-related diseases, nutrition is pivotal in understanding treatment outcomes. However, collecting dietary data in observational studies can be both burdensome and costly.

Objectives: Using Crohn’s Disease (CD) as an example, the objective was to describe dietary data collection methods in identified observational CD studies, and to provide considerations for future studies that are applicable across different indications.

Methods: A targeted literature review in Embase and MEDLINE was conducted to identify observational CD studies that collected dietary data. Dietary data collection methods of studies are described, and recommendations for future observational studies are presented.

Results: 220 study abstracts were identified and screened, with 129 observational studies including patients with CD that collected dietary data. 89 studies (69.0%) focused on adults, while the remainder included children or both age groups. Data collection methods included food frequency questionnaires (FFQs) (49 [38.0%]), food diaries (46 [35.7%]), both (15 [11.6%]), or other methods (19 [14.7%]). Thirteen studies (10.1%) investigated outcomes of diet-based therapies, while only 2 studies (1.6%) collected dietary data when assessing drug treatment outcomes, highlighting a gap in integrating dietary data with treatment outcomes.
Considerations for collecting dietary data:
• Retrospective studies: Cross-sectional data may be gathered using validated FFQs, which require minimal patient effort and cover a 30 day to 1 year recall period. Despite potential limitations (recall bias, not covering the entire follow-up period, need for consent), FFQs can provide valuable insights and be administered/analyzed electronically, offering efficiencies in completion and analytics.
• Prospective studies: FFQs or tailored questionnaires at multiple timepoints can provide generalized intake data (e.g., usual nutrient intakes). For detailed dietary information during specific timeframes (e.g., macro/micronutrients), food diaries are recommended despite their higher burden. Food diaries can reduce patient burden and improve data quality when patients are given proper instructions and data is collected through structured electronic dietary platforms.
• Method selection: When selecting the appropriate data collection method and technologies, factors such as geographic location, age, and cultural background should also be considered.

Conclusions: Dietary data collection methods were highly varied among observational CD studies, with few collecting dietary data when evaluating drug treatment outcomes. Future methodological selection should consider objectives, patient burden, data quality, and population appropriateness.