Role of High PTH in Developing Cardiac Diastolic Dysfunction in Pre-dialysis & MHD Patients

Abstract

Background: End-stage kidney disease (ESKD) poses a significant global health challenge. Approximately 70% of ESKD patients undergo hemodialysis (HD) or peritoneal dialysis (PD), and cardiovascular disease (CVD) is their leading cause of death, with a 9% annual mortality rate. Cardiac issues such as left ventricular hypertrophy (LVH) and dysfunction are prevalent in these patients, often worsening with dialysis. Secondary hyperparathyroidism (SHPT) due to impaired kidney function contributes to vascular calcifications, affecting cardiovascular health. Aim of the study: This study aims to elucidate the role of high PTH in developing cardiac diastolic dysfunction in both pre-dialysis and hemodialysis. Methods: The study conducted at the Department of Nephrology in BSMMU, Dhaka, Bangladesh, observed 80 CKD patients on hemodialysis over a year (from November 2022 to September 2023). Participants met specific criteria and provided informed consent. Data collection involved medical and socioeconomic history, physical examinations, anthropometric measurements, and blood tests. Tests included hematological, biochemical, and hormonal analyses, with serum iPTH measured by chemiluminescent assay. Echocardiograms assessed cardiac function and morphology. Inclusion criteria involved age (18-65), CKD stage 4 or 5, and > six months on hemodialysis, while exclusion criteria included certain cardiac, renal, and systemic conditions. Result: The study included 80 participants, primarily male (63.7%), with an average age of 43.1±12.9 years. Elevated iPTH levels were strongly linked to higher serum phosphate (p=0.026), Ca × PO4 product (p=0.010), and LVMI (p=0.001), as well as increased LA diameter (p<0.001). Multivariate analysis identified elevated iPTH as a significant predictor of diastolic dysfunction (p=0.002, OR 1.01). High iPTH levels correlated with worsening diastolic dysfunction and higher serum phosphate levels. Conclusion: Parathyroid hormone (PTH) levels contribute to cardiac diastolic dysfunction in pre-dialysis and maintenance hemodialysis patients. High PTH is linked to increased serum phosphate, calcium-phosphate product, and left atrial diameter, emphasizing the need to monitor PTH levels to prevent cardiovascular complications in chronic kidney disease.