Associations of dietary macronutrients and energy intake with diabetic kidney disease and all-cause mortality in diabetes: evidence from NHANES
Qiuhong Li, Xiaomeng Lv, Liuwei Wang, Yulin Wang, Yanhong Guo, Lu Yu, Zihan Zhai, Zhibin Huang, Lin TangIntroduction
Dietary management is crucial for diabetes, yet the impact of macronutrient and energy intake on diabetic kidney disease (DKD) and all-cause mortality remains unclear. This study aimed to investigate these associations and to identify intake levels that were associated with the lowest odds of DKD and mortality.
Research design and methods
Using combined cross-sectional and prospective data from NHANES (2011–2018), we analyzed 3066 diabetic adults (representing 30.3 million individuals in the USA). Weighted logistic regression was used to assess the prevalence of DKD, while Cox regression was employed to evaluate associations with all-cause mortality, incorporating dose-response analyses and mediation testing.
Results
After multivariable adjustment, higher protein and dietary fiber intake showed significant inverse linear associations with DKD (P-trend <0.05). Compared with the lowest quartile (Q1), the highest quartile (Q4) had significantly lower DKD odds: protein (OR=0.41, 95% CI 0.21 to 0.79) and fiber (OR=0.50, 95% CI 0.31 to 0.82). The statistical inflection points associated with lower DKD odds were protein >74 g/day and fiber >14 g/day. Exploratory mediation analysis suggested that body mass index and hemoglobin partially explained the associations of proteins and fibers with DKD, respectively. Prospectively, after 48 months median follow-up (366 deaths, representing 3.36 million), only energy intake exhibited a significant U-shaped association with mortality risk (non-linear p<0.05). Mortality was lowest with daily energy intake between 1750 kcal and 1810 kcal.
Conclusions
In this observational analysis, higher protein (>74 g/day) and fiber intake (>14 g/day) were associated with lower DKD prevalence in diabetes, while maintaining daily energy within 1750–1810 kcal is associated with the lowest all-cause mortality risk. These findings suggest potential reference values for dietary patterns in diabetes management.