ABSTRACT
Objective:Using 24-hour urinary sodium excretion (24h-UNa) as the surrogate measure of sodium intake, to evaluate the joint association of 24h-UNa and serum 25-hydroxy vitamin D (25-OHD) levels with the risk of albuminuria in patients with type 2 diabetes mellitus (T2DM).Methods:This retrospective study included 670 hospitalized T2DM cases in the Department of Endocrinology and Metabolic Diseases, the First Affiliated Hospital of Zhengzhou University from January 2018 to October 2021. Patients were divided into the albuminuria-positive group or negative-group according to the level of 24-hour urinary albumin excretion (24h-UAE); They were also divided into the high-sodium group or low-sodium group according to the level of 24h-UNa; Patients were divided into the low-VD group or high-VD group according to the level of 25-OHD. Combining 24h-UNa and 25-OHD, the patients were further divided into four groups: high-VD low-sodium group ( n=85), high-VD high-sodium group ( n=122), low-VD low-sodium group ( n=248), and low-VD high-sodium group ( n=215). The effect of 24h-UNa and 25-OHD association on albuminuria was analyzed by binary regression. Results:There were significant differences in 24h-UAE level among the four groups ( P<0.01), the level of 24h-UAE in the low-VD high-sodium group was significantly higher than that in low-VD low-sodium group, high-VD low-sodium group, and high-VD high-sodium group [39.00(13.00, 319.00)mg/24 h vs 22.00(10.00, 99.00)mg/24 h, 22.00(9.00, 72.50)mg/24 h, 22.45(9.69, 72.75)mg/24 h; P=0.047, P=0.019, P=0.030]. Correlation analysis showed a positive correlation between 24h-UNa and 24h-UAE in the low-VD group ( P=0.017), but not in the high-VD group ( P=0.411). Binary regression analyses showed that both 24h-UNa ( P=0.017) and 25-OHD( P=0.023) were independent risk factors for positive albuminuria in patients with T2DM. The risk of positive albuminuria in the low-VD high-sodium group was 1.789 times higher than that in the high-VD low-sodium group ( P=0.037). Conclusion:24h-UAE in T2DM patients was affected by the combination of 24h-UNa and 25-OHD. A low level of 25-OHD increased the risk of albuminuria in high sodium intake T2DM patients.