Analytical study: Association of Parathyroid Hormone (PTH) and Estimated Glomerular Filtration Rate (eGFR) in Pre-Dialysis CKD Patients.
Year: 2025
Type: preprint
Study design: Observational Study
Abstract: Introduction: Chronic kidney disease (CKD) is associated with mineral and bone disorders (CKD-MBD) which starts early and worsens with disease progression. increased Parathyroid hormone (PTH) is the main Initial serum biochemistry abnormality along with increased fibroblast growth factor 23 (FGF23) , decreases in 1,25 dihydroxy vitamin D (calcitriol) and soluble α-Klotho (Klotho), maintaining serum calcium and phosphate within normal ranges for a periods . As CKD advance, hyperphosphatemia develops in the majority of patients, leading to continuous stimulation of PTH synthesis and secretion, resulting in secondary hyperparathyroidism (SHPT), a major metabolic complications of CKD. Understanding the pathophysiology of PTH and analyzing its interaction with key laboratory parameters especially esitimated Glomerular Filtration Rate (eGFR) is crucial for reducing SHPT- associated complications. Aim: This study aimed to investigate the relationship between key laboratory parameters specifically PTH and eGFR, across different CKD stages. Methods: A cross-sectional analytical study was conducted on a sample of 113 pre-dialysis CKD patients at varying stages of disease progression. Laboratory assessments included serum urea, creatinine, electrolytes, PTH, calcium, phosphate, and eGFR. Statistical analyses utilized Pearson’s correlations and one-way ANOVA via JASP software to explore associations between PTH levels and renal function markers. Results: Hypertension (90.3%) and diabetes (53.1%) were the most prevalent comorbidities. The mean eGFR was (18.19 mL/min/1.73m²), reflecting advanced CKD stages. A significant inverse correlation was observed between PTH and eGFR (r = -0.275, 95% CI: [-0.437, -0.095], p = 0.003). Although mean PTH levels showed a trend of increase across CKD stages, this difference was not statistically significant (p = 0.105). Electrolyte analysis revealed phosphorus retention and calcium reduction with CKD progression. ANOVA results showed a highly significant effect of CKD stage on eGFR (F(2, 110) = 347.062, p < 0.001) This effect was massive, accounting for a substantial portion of the variance in eGFR (ω² = 0.860, 95% CI: [0.814, 0.890]) , but not on PTH. Variability in PTH response across stages may reflect therapeutic interventions or individual differences. Conclusion: While the difference in mean PTH levels across CKD stages was not statistically significant, The study did reveal a significant inverse correlation between PTH and eGFR. This, coupled with the clear evidence of mineral metabolism disturbances (i.e., phosphorus retention and calcium reduction), emphasizing the importance of individualized monitoring and early intervention strategies in CKD management. Keywords: Secondary Hyperparathyroidism, Mineral Bone Disorder, Estimated glomerular filtration rate (eGFR).
Author: Fatima Alsulymani
Language: English
Subfield: Nephrology
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W7106422566