Impact of Successful Secondary Hyperparathyroidism Treatment on Cardiovascular Morbidity in Patients with Chronic Kidney Disease Stage IIIB-V

Abstract

Abstract Background Chronic kidney disease (CKD) patients grade III B(GFR 30-44ml/min), IV (GFR 15-29ml/min) and grade V (GFR <15ml/min) are patients with a severe chronic Kidney disease that are shortly before or in need of dialysis. 61.7% of patients on hemodialysis have been found to have secondary hyperparathyroidism. It has been associated with high cardiovascular morbidity by calcification of tissue leading to lung fibrosis and right heart insufficiency. Aims To assess the effect of treatment success of secondary renal hyperparathyroidism (SHPT) on cardiovascular morbidity. Methods Retrospective single-center analysis. 211 patients chronic kidney disease (CKD) stages IIIB-V undergoing computed tomography for coronary artery calcium (CAC) scoring at the University Hospital of Zurich between 2015 and 2019. Presence of and control of SHPT was assessed at the timepoint of CAC scoring, and 6-12 months prior. Information on left ventricular ejection fraction (LVEF), and left ventricular hypertrophy (LVH) were obtained from echocardiography at the timepoint of CAC scoring. Independent predictive factors for ACS and LVH were assessed by multivariable analysis. Results 34% (n=72) of the patients had uncontrolled SHPT, whereas 66% (n=139) had either no-(n=98) or a controlled SHPT(n=41). Patients with uncontrolled SHPT had a significantly lower LVEF (p=0.028), significantly more pronounced LVH (p=0.003), a higher left ventricular myocardial mass index (LVMMI) (p=0.002) than the group with no SHPT or well controlled SHPT. Uncontrolled SHPT had a significant higher risk for developing ACS (p=0.011) compared to no-or controlled SHPT patients (41.7% vs 31.7%). Conclusions Insufficient control of SHPT has a negative impact on cardiovascular morbidity with lower LVEF, increased LVH and a higher incidence of ACS. Increased focus on SHPT control in CKD patients is important and may have a beneficial impact on cardiovascular outcomes. If all conservative measures do not lead to a sufficient alignement of the secondary hyperparathyroidism parathyroidectomy may be indicated.