- Secondary hyperparathyroidism (SHP) negatively affects survival of patients with end stage renal disease on dialysis.
- Achieving even once the three KDOQI targets of mineral metabolism (Ca, P and PTH) has been associated with lower risk of mortality (  (full text)). PTX, performed to improve biochemical control, may improve survival.
Aim of the study
- To evaluate, in a cohort of Italian dialysis patients, the impact of PTX on biochemical control and on medium term survival
- We collected data from 149 hemodialysis Units spread throughout the Country (figura 1) (figura 2), by means of a data sheet filled by a reference physician.
- The study population included all prevalent patients aged ≥ 18 years receiving dialysis therapy (hemodialysis or peritoneal dialysis).
- Follow-up data were requested on a yearly basis for 3 consecutive years.
- Out of a total 12.515 receiving dialysis, we recorded 527 living PTX cases (prevalence = 4,2%), 231M/296F, aged 57.9±12.5 years, on dialysis since 14.5±8.3 y. Time from surgery was 6.0 y (3.0-9.0; M, IQR).
- We then aimed at obtaining a control group comparable for age, sex and dialysis duration
- From the same total population we recorded 432 cases, 192M/240F, aged 58.9±16.5 years, on dialysis since 11.7±7.6 y.
- Table I (figura 3) shows mean clinical and biochemical parameters in the PTX and C patients.
- PTX patients had lower Ca (8.76±0.87 vs 9.05±0.73 mg/dl; p <.05), P mg/dl (4.90±1.36 vs 5.10±1.34 mg/dl; p<.05) and PTH (181.9±292.5 vs 333.7±293.7 pg/ml; p<.01) (figura 3).
- At enrollment the percentage of patients at K-DOQI targets was lower in the PTX group: Ca = 50,9% vs 57,6 (p<.001); P = 55,3% vs 58,8 (p<.05); PTH =17% vs 35% (p<.001) (figure 4).
- During the follow up PTH was confirmed to be less frequently at target in the PTX group (1° and 2° year of follow-up).
- Also P and Ca, although not invariably, resulted to be less frequently at target in the PTX group (P in the second year of follow-up and Ca in the third year). (figure 5)
- In multivariate adjusted analysis, subdistributional-HR for all-cause mortality was 0,843 (CI 0,783-0,908; p<.0001) for PTX patients.
- This is the first and largest nationwide clinical report on Italian dialysis patients who received PTX.
- There is evidence that biochemical control of mineral metabolism, as recommended by international guidelines, is not improved by surgery. In fact, none of the three biomarkers (Ca, P, PTH) showed better control at enrollment and during medium term follow-up, as compared to controls.
- In any case, PTX in our observation was associated with a reduced mortality rate.
- We conclude that, in dialysis patients, PTX associates with improved survival in a medium term follow-up, regardless of achievement of Ca, P or PTH targets.