PARATHYROIDECTOMY MAY SLOW CARDIOVASCULAR CALCIFICATION IN DIALYSIS-DEPENDENT PATIENTS

Introduction:

Vascular calcification (VC) is prevalent in patients with end stage kidney disease on dialysis, especially in those with secondary hyperparathyroidism (SHPT). The dynamics of VC after surgical treatment of SHPT are poorly understood. We aimed to test the following hypothesis: parathyroidectomy (PTx) may slow down coronary artery calcification (CAC) and abdominal aortic calcification (AAC) in dialysis patients with severe SHPT in comparison with conservative treatment.

Methods:

The prospective cohort study (NCT 03937349) included 63 dialysis-dependent patients with severe SHPT. Of them, 45 patients completed the study. Patients of study group underwent subtotal (n=24) or total PTx with autotransplantation of parathyroid tissue (n=15). Control group included 6 previously untreated patients with SHPT in whom cinacalcet was initiated in order to control parathyroid hormone (PTH) level.  In both groups, cardiac computed tomography scan (quantification of coronary calcium by Agatston method, primary outcome) and lateral lumbar X-ray (semi-quantitative Kauppila score) were performed to assess VC before and 18 months after surgery. Levels of serum total calcium, phosphorus, PTH, and alkaline phosphatase before and 18 months after surgery were also evaluated. Patients were excluded if they had HPT persistence / recurrence, kidney transplantation, or lost to follow-up.

Results:

Patients of the control group were more likely to be male (p=0,0265) and had less dialysis vintage (16 [Q1-Q3: 4; 27] months vs 51 [Q1-Q3: 31; 110] months in PTx group). Otherwise, there were no differences between the groups at the baseline.

Prevalence of CAC before PTx was 80% (n=36), and 58% (n=26) of patients had AAC at the baseline.

Descriptive statistics of CAC and AAC at the baseline and at the follow-up are given in Tab.1. Overall, in both groups CAC and AAC scores increased by the 18 months. Median of difference between CAC scores (month 18 – month 0) in control group was 241.5 [IQR 27; 1079], 0 to 6793 AU, which was slightly higher than that of the PTx group: 4 [IQR: -36; 131], -1252 to 12322 AU, p=0.079 (Mann–Whitney U test) – Fig.1. Differences for the differences for secondary endpoints (main coronary arteries, valves, and AAC) are summarized in Tab.2.

Conclusions:

The prevalence of vascular calcification in dialysis-dependent patients with severe SHPT is high. PTx may be associated with slower progression of CAC compared to standard conservative treatment of SHPT, although the observed effect was small, probably due to the small size of the control group. Recruitment to the study is being extended.

I have no potential conflict of interest to disclose.

I did not use generative AI and AI-assisted technologies in the writing process.