(P11-005-25) Effectiveness of Diet Quality on Fatigue, Physical Function, and Inflammation in Older Adults With Long-COVID: LongCOVIDiet Study Protocol for RCT

Objectives: The Long-COVIDiet Study is a virtual dietary intervention designed to mitigate Long-COVID symptoms and promote recovery. As of 2024, approximately 17 million U.S. adults experience Long-COVID, with fatigue being the most prominent symptom, significantly impacting quality of life and physical function capacity. Residual pro-inflammatory cytokine responses following COVID-19 and a diet high in pro-inflammatory foods may exacerbate these conditions and impede recovery. The primary objective is to evaluate the effectiveness of the Long-COVIDiet intervention in improving diet quality, alleviating fatigue, and preserving physical function in older adults with Long-COVID. Secondary objective includes exploring potential mechanisms by analyzing biomarkers and their relationships to symptom improvement.

Methods: A randomized controlled trial with 56 participants aged 50+ years with Long-COVID symptoms of, moderate-to-severe fatigue (Brief Fatigue Inventory, BFI≥4), with poor diet quality (Mini-EAT < 60). Participants will be randomly assigned (1:1) to:

1. The intervention includes weekly group consultations with a registered dietitian, guided by the U.S. Healthy Style Diet as outlined in the recent Dietary Guidelines for Americans 2025-2030 (DGA). The program prioritizes the inclusion of anti-inflammatory nutrients and incorporates daily supplementation with vitamin D (2000 IU), omega-3 fatty acids (1000 mg), and sufficient whey protein to achieve an overall daily protein intake of 1.2–1.5 g/ body weight kg.

2. Attention Control includes education on healthy aging, excluding nutrition advice, with a similar frequency of meetings.

Primary outcome measurements at baseline, 4, 8, 12, and 16 weeks include diet quality (HEI-2020 via ASA24), fatigue (BFI), physical function (SPPB), and quality of life (SF-36). Pre- and post-trial nutritional and inflammatory biomarkers will assess mechanisms of such diet. Recruitment is via advertisements, primary care practices and EMR.

Results: N/A

Conclusions: We anticipate that the intervention will be effective in changing dietary intake and thereby reducing prominent Long-COVID symptoms compared to control. This study has the potential to provide a scalable approach and lay the groundwork for future precision or personalized nutrition research.

Funding Sources: National Institute on Aging, K01AG078545