Relationship between Serum 25(OH)D Levels and Blood Pressure in Children with Nephrotic Syndrome

BACKGROUND: Vitamin D plays an eminent role in the renin-angiotensin system that may interfere with blood pressure regulation. Children with nephrotic syndrome (NS) are often observed with low serum vitamin D levels that may lead to Vitamin D deficiency status. AIM: This study aimed to investigate the correlation between serum vitamin D [25(OH)D] levels and blood pressure in children with NS. METHODS: A cross-sectional, observational analytic study was conducted in 35 children NS with minimal change diseases from February to August 2019 in Haji Adam Malik General Hospital, Medan. Blood pressure was examined and serum Vitamin D levels along with serum creatinine, albumin, and calcium were measured. RESULTS: Of 35 children, 21 children (60%) had proteinuria. Regarding the category of Vitamin D status, there were 40% and 34.3% with deficiency and severe deficiency of Vitamin D, respectively. The median serum Vitamin D levels were not significantly different among the age group. Children with proteinuria showed lower serum Vitamin D levels (P < 0.001). There was an elevation of systolic and diastolic blood pressure in children with proteinuria (P = 0.039 and P = 0.036, respectively). Our study showed a weak negative correlation between serum Vitamin D levels and either systolic or diastolic blood pressure (r-0.114 and r-0.174, respectively). CONCLUSION: Both Vitamin D deficiency and severe deficiency are common in children with NS. In this study, serum Vitamin D levels have been shown to have a weak negative correlation with blood pressure in children with NS.