Associations of healthy dietary patterns with mortality among people with prediabetes

Purpose To examine the associations of healthy dietary patterns with cardiometabolic biomarkers and all-cause mortality among individuals with prediabetes. Methods This cohort study included 8363 adults with prediabetes from the National Health and Nutrition Examination Survey 1999–2014. Healthy dietary patterns including Alternate Healthy Eating Index-2010 (AHEI-2010), Alternate Mediterranean Diet score (AMED), Dietary Approaches to Stop Hypertension score (DASH), and Healthy Eating Index-2015 (HEI-2015) were calculated based on 24-h dietary recall data. Mortality status was obtained by linkage to National Death Index records. Cardiometabolic biomarkers, including blood glucose, insulin, HbA1c, C-reactive protein (CRP), and lipids, were measured at recruitment. Results During 61,991 person-years of follow-up, 991 deaths occurred. Comparing the extreme quartiles, the multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality were 0.65 (0.49, 0.85) for AHEI-2010 ( P -trend = 0.002), 0.68 (0.50, 0.92) for AMED ( P -trend = 0.004), 0.72 (0.53, 0.98) for DASH ( P -trend = 0.03), and 0.78 (0.58, 1.05) for HEI-2015 ( P -trend = 0.08). Besides, the HRs (95% CIs) for all-cause mortality per 20-percentile increment in scores were 0.78 (0.67, 0.90) for AHEI-2010 ( P = 0.001), 0.73 (0.62, 0.86) for AMED ( P < 0.001), 0.84 (0.69, 1.02) for DASH ( P = 0.08), and 0.86 (0.74, 1.00) for HEI-2015 ( P = 0.04). In addition, higher dietary scores were associated with favorable blood glucose, insulin, HOMA-IR, blood lipids, and CRP (all P -trend < 0.05). The high-density lipoprotein cholesterol and CRP explained 1.53–9.21% of the associations between dietary patterns and all-cause mortality ( P < 0.05). Conclusions Diets with higher AHEI-2010, AMED, DASH, and HEI-2015 were associated with improved cardiometabolic factors and lower all-cause mortality among individuals with prediabetes. These findings suggest that multiple healthy dietary patterns instead of a one-size-fits-all diet plan might be beneficial and acceptable for individuals with prediabetes.