Dietary patterns trends of US adults with undiagnosed and diagnosed hyperlipidemia and their relationship with long-term mortality: NHANES 2007-2018

Background Dietary intervention is an important component of treating hyperlipidemia. There are many people with undiagnosed hyperlipidemia, and the dietary patterns of population with undiagnosed and diagnosed hyperlipidemia in US have not been studied. The purpose of this study was to explore the dietary pattern trends of the population with undiagnosed and diagnosed hyperlipidemia in the past decade and their correlation with mortality. Methods The sample data came from the National Health and Nutrition Examination Survey from 2007 to 2018. The dietary patterns were assessed using Dietary Inflammatory Index (DII) and Healthy Eating Index (HEI). The relationship between DII and HEI and mortality in individuals with hyperlipidemia were evaluated by Cox proportional hazards model. We conducted subgroup analysis to evaluate the potential relationship between DII and HEI and covariates. Results Of 29897 individuals included, 9815 without hyperlipidemia (age: weighted mean [WM] 39.91 years; 95% confidence interval [CI] 39.31–40.51; male: weighted proportion 49.4%), 9815 with undiagnosed hyperlipidemia (age: WM 45.65 years; 95% CI 45.08–46.23; male: weighted proportion 55.3%), and 10817 with diagnosed hyperlipidemia (age: WM 57.33 years; 95% CI 56.82–57.83; male: weighted proportion 50%). The proportion of population with undiagnosed hyperlipidemia shown an upward trend. The DII of each group showed an increasing trend, while the HEI showed a decreasing trend. Compared with participants with diagnosed hyperlipidemia, the participants with undiagnosed hyperlipidemia had higher DII (WM: 1.11; 95% CI: 1.04–1.18 versus WM: 0.94; 95% CI: 0.86–1.02) and lower HEI (WM: 50.26; 95% CI: 49.71–50.81 versus WM: 52.38; 95% CI: 51.84–52.93). The median follow-up time for survival analysis was 9.7 years, and high DII (hazard ratio [HR]: 1.09; 95% CI: 1.03–1.15) and low HEI (HR per 1 SD increase: 0.89; 95% CI: 0.81–0.98) were associated with an increased risk of all-cause mortality in individuals with hyperlipidemia. Conclusions From 2011 to 2018, the dietary health and inflammatory potential of US adults were deteriorating, especially those with undiagnosed hyperlipidemia. High DII and Low HEI are associated with an increased risk of all-cause mortality.