Giving Voice to Low-Income Older Adults with T2DM: Design and Evaluation of the JTG Dietary Management System in a Carbohydrate-Centric Culture (Preprint)

BACKGROUND Background: Dietary management is central to T2DM care, yet low-income older adults in northern China face cultural, economic, and literacy barriers. Digital tools rarely reflect carbohydrate-centric eating patterns or the usability needs of this population. OBJECTIVE Objective: To design and evaluate Jintang Weishi (JTG), a culturally tailored dietary management system for low-income older adults with T2DM in Shanxi. METHODS Methods: We conducted a 90-day randomized controlled trial (N=40; age ≥55 years) in Shanxi, China, enrolling participants from low-income households, defined as monthly household income <¥3,000 for urban residents and <¥1,750 for rural residents. Participants were randomized to receive JTG plus standard care or standard care alone. Primary outcomes were diabetes knowledge (DKT), daily carbohydrate intake, and HbA1c, assessed at baseline, intervention completion, and follow-up. Usability was evaluated through a 10-item user survey. Randomization balanced baseline knowledge. RESULTS Results: The intervention group showed large gains in DKT (mean ΔT2–T0=+9.3 vs +0.1 in controls; P<.001), substantial reductions in daily carbohydrate intake ( – 414.1 Kcal vs –13.2 Kcal; between-group difference –400.9 Kcal, 95% CI –506.4 to – 295.4; t₃₈=–7.45; P<.001), and a greater HbA1c decline (–1.18 percentage points from 8.02% to 6.84% vs –0.01 in controls; P<.001). Usability ratings indicated high acceptability among older users CONCLUSIONS Conclusions: In a setting where staple diets are carbohydrate-heavy and digital literacy varies, a culturally adapted, patient-centered system improved knowledge, diet, and short-term glycemic control. Future work should evaluate durability and mechanisms of change over longer follow-up and examine implementation pathways that integrate multidisciplinary support and community-based services to sustain engagement and scale impact