Association of the Type and Amount of Dietary Proteins with Microalbuminuria: Tehran Lipid and Glucose Study

Introduction: Microalbuminuria is an independent risk factor for cardiovascular disease and is associated with all-cause mortality. The present study aimed to investigate the possible association between different types and amounts of dietary protein and microalbuminuria among Iranian adults participating in the Tehran Lipid and Glucose Study (TLGS). Materials and Methods: Adults (1192 men and women; aged 19-86 years) participating in the sixth phase of TLGS (2014-2017), who had complete nutritional data with known urinary microalbumin levels, were included in the present study, according to the inclusion criteria. The dietary intake was assessed using a validated Feed Frequency Questionnaire (FFQ). Demographic variables, anthropometric indices, blood pressure, and biochemical data were also measured. To estimate the odds ratio (OR) of microalbuminuria (urinary microalbumin level: 20-200 mg/L), a logistic regression analysis adjusted for the confounding variables was performed. Results: The mean (±SD) of the participants’ age and body mass index at baseline were 44.96±14.00 years and 27.81±4.97 kg/m2, respectively. The prevalence of microalbuminuria in the study population was 14.4%. After adjusting for the confounding variables, the OR of microalbuminuria did not show a significant relationship with the protein intake. The adjusted ORs and 95% confidence intervals for microalbuminuria in the third tertile of total protein intake, animal protein intake, and plant protein intake were 1.08 (0.57-2.05), 1.19 (0.67-2.09), and 1.02 (0.56-1.88), respectively. Conclusion: In the present study, there was no significant association between the total protein and plant protein intake and microalbuminuria. The animal protein intake increased the risk of microalbuminuria, although this relationship was not statistically significant.