Study of Renal Biomarkers, Electrolyte Imbalance and Vitamin D Levels in Hypertensive Subjects: A Case Control Study

Abstract

Background: Hypertension remains the leading modifiable risk factor for global mortality, affecting approximately 33% of adults worldwide. The interplay between renal function, electrolyte homeostasis, and vitamin D status in hypertensive patients has garnered increasing clinical attention. This study aimed to estimate and correlate renal biomarkers, electrolyte levels, and vitamin D status in hypertensive subjects compared to normotensive controls. Materials & Methods: A case-control study was conducted at Siddhartha Medical College, involving 30 hypertensive subjects and 30 age-matched normotensive controls aged 21-55 years. Serum levels of sodium, potassium, chloride, urea, creatinine, uric acid, and vitamin D were measured using standardized laboratory methods. Blood pressure was recorded using a mercury sphygmomanometer, and anthropometric measurements were obtained. Statistical analysis employed Student's t-test and Pearson's correlation coefficient, with P<0.05 considered significant. Results: Hypertensive subjects demonstrated significantly lower serum sodium (139.13±3.025 vs. 143.8±2.26 mmol/L; P<0.0001) and chloride (103.63±2.96 vs. 109.1±2.12 mmol/L; P<0.0001) compared to controls. Renal biomarkers were significantly elevated in cases: urea (25.33±9.26 vs. 20.06±6.34 mg/dL; P=0.0099), creatinine (1.05±0.57 vs. 0.81±0.39 mg/dL; P=0.0006). Vitamin D levels were significantly lower in hypertensive subjects (18.27±4.01 vs. 20.25±6.32 ng/mL; P=0.0184). Anthropometric parameters including BMI (25.33±3.27 vs. 22.47±1.78 kg/m²; P<0.0001) were significantly higher in hypertensive subjects. Correlation analysis revealed significant relationships between systolic blood pressure and creatinine (r=+0.452), sodium (r=-0.512), and vitamin D (r=-0.423). Conclusion: This study confirms that hypertensive patients exhibit significant renal impairment, electrolyte disturbances, and vitamin D deficiency. The correlations identified between these parameters highlight the need for integrated clinical assessment and therapeutic strategies targeting vitamin D supplementation and electrolyte optimization in hypertension management. These findings support incorporating routine monitoring of renal function, electrolytes, and vitamin D status in hypertensive populations to enable early intervention and potentially improve cardiovascular outcomes.

Keywords: Hypertension, renal biomarkers, electrolytes, vitamin D, creatinine, sodium, case-control study