Association of dietary iron intake with diabetic kidney disease among individuals with diabetes.

PURPOSE: The current study investigated the correlation between dietary iron intake and diabetic kidney disease among diabetic adults. METHODS: This cross-sectional study enrolled 8118 participants who suffered from diabetes from the National Health and Nutrition Examination Survey (NHANES) 1999-2018. Dietary iron intake was obtained from 24 h recall interviews, and diabetic kidney disease was defined as eGFR < 60 mL/min per 1.73 m2 or albumin creatinine ratio (ACR) ≥ 30 mg/g. Three weighted logistic regression models were utilized to investigate odd ratio (OR) and 95% CIs for diabetic kidney disease. Stratified analyses were performed by gender, age, BMI, HbA1c, hypertension status, and smoking status, and diabetes types. RESULTS: Among 8118 participants (51.6% male, mean age 61.3 years), 40.7% of participants suffered from diabetic kidney disease. With the adjustment of potential covariates, we found that ≥ 12.59 mg of dietary iron was related to a lower risk of diabetic kidney disease (OR = 0.78, 95% CI: 0.63 to 0.96; OR = 0.79, 95% CI: 0.63 to 0.98). In stratified analyses, higher iron intake was negatively related to diabetic kidney disease, especially among those who were male, < 60 years, those with hypertension, those with HbA1c < 7.0%, and those who were ex-smokers. The result remained robust in sensitivity analyses. CONCLUSION: We found that ≥ 12.59 mg of dietary iron is associated with a lower risk of diabetic kidney disease, especially in those who were male, younger, heavier weight, have better blood sugar control, and those who were ex-smokers.

Association between dietary protein intake and mortality among patients with diabetic kidney disease.

AIMS: This study aimed to investigate the association between dietary protein intake and mortality among patients with diabetic kidney disease. METHODS: The research encompassed a total of 2901 participants diagnosed with diabetic kidney disease, drawn from the National Health and Nutrition Examination Survey (NHANES). To determine outcomes related to all-cause and cardiovascular mortality, connections were established with the National Death Index up until December 31, 2019. Estimations of hazard ratios (HRs) and their corresponding 95 % confidence intervals (CIs) were conducted using Cox proportional hazard ratio models. RESULTS: During the 261,239 person-years of follow-up, 1236 deaths were recorded. After multivariate adjustment, the weighted hazard ratio (HR) and 95 % CIs for participants with 1.0-1.2 g/kg of protein intake was 0.65 (0.44, 0.96) for all-cause mortality. A higher proportion of animal protein intake was found to be associated with an increased mortality risk. Stratified analyses showed that higher protein intake benefited older participants. CONCLUSIONS: In diabetic kidney disease patients, 1.0-1.2 g/kg of protein was associated with lower mortality and 0.6-1.2 g/kg of protein especially benefitted patients ≥60 years.