Life Course Change Towards a Plant-Centered Diet and Incidence of Type 2 Diabetes: The Coronary Artery Risk Development in Young Adults (CARDIA) Study (OR33-03-19)

Abstract

ObjectivesThere has been limited study of long-term change towards a plant-centered diet in relation to incident type 2 diabetes (T2DM). We examined this question in the Coronary Artery Risk Development in Young Adults (CARDIA) cohort. MethodsAnalyses included 2717 participants in CARDIA, a US multicenter, community-based prospective cohort study, currently with 30 years of follow-up. Participants were free of diabetes through year 20, with follow-up for incident T2DM through year 30. Dietary intake at years 0 and 20 was assessed by interviewer-administered diet history; overall dietary quality was assessed using a hypothesis-driven index based on 46 food groups, the A Priori Diet Quality Score (APDQS). The APDQS has possible scores 0 to 132 and increasing score is largely led by consumption of nutritionally rich plant foods–fruits and vegetables and plant-derived fats (e.g., seeds, nut, vegetable oils) and proteins (e.g., avocado, legume, soy). Change in diet quality (year 20 – year 0) and its quintiles were calculated. Diagnosis of T2DM was based on self-reported use of antidiabetic medication treatment or lab tests (fasting glucose, 2-hour glucose, or glycated hemoglobin). In proportional hazards regression, covariates included sociodemographics, baseline APDQS, and time-varying energy intake, smoking, and physical activity. ResultsMean baseline age was 25.0 ± 3.6y, 43% were black, and 58% were women. During 10 years of follow-up after year 20, 206 cases of incident T2DM occurred. Mean year 0 APDQS was 64 ± 13 points and mean 20-year changes in APDQS was 7 ± 11. In multivariable-adjusted analysis, we found that the greatest increase in dietary quality over 20 years (median APDQS increased by 22 points) was associated with a 60% decrease in risk of T2DM as compared to a small decrease in diet quality (median APDQS decreased by 8 points); HRQ5 vs. Q1: 0.40; 95% CI:0.24–0.67). For every 10-point increase in APDQS over 20 years, there was a 23% decrease in risk of T2DM (95% CI: 0.67–0.88, P-trend = 0.0009). The pattern of findings persisted within below median and within above median year 0 APDQS. ConclusionsOur finding suggests that young adults would benefit from improving diet quality by shifting toward a more plant-centered diet over time for the prevention of T2DM. Funding SourcesThis research was funded by an NHLBI contract and the University of Minnesota Healthy Food, Healthy Lives Institute. Supporting Tables, Images and/or Graphs▪▪