CAVE PTX study aims to evaluate, in dialysis patients submitted to PTX, the control and therapies of divalent ions (phase I), and the prevalence of aortic calcifications and vertebral fractures (phase II). We report here the phase I results.
Biochemistries and therapies of PTX patients were collected by means of an electronic data sheet from 149 Italian dialysis Units. A control group (C), comparable for age, sex and dialysis duration, was selected from the whole cohort.
From a total of 12515 patients (HD = 87.7%;PD = 12.3%), 528(4.22%) had received PTX. Prevalence of PTX was definitely higher in HD(4.5%) compared to PD(1.9%). Cases and C(n=437) characteristics are compared in table 1.
Age,y
M/F,%
Dialysis,y
Ca,mg/dl
P,mg/dl
PTH,pg/ml
PTX
58±13
56/44
15±8
8.8±0.8
4.9±1.3
182±292
C
58±17
54/46
12±13(#)
9.0±0.7(#)
5.1±1.3(*)
334±294(#)
(*)p<.05, (#)p<.001 vs PTX.
Respectively in PTX and C, PTH was low(<150) in 64 vs 23%; optimal(150-300) in 17 vs 39%; and high(>300) in 19 vs 38%. Ca, P and PTH values in the three K/DOQI PTH range groups are in table 2.
8,6±0.8
9.0±0.9#
8.9±0.7
9.0±0.7
9.2±0.8
9.0±0.7#
4.8±1.3
4.9±1.5
4.8±1.2
5.1±1.3
5.5±1.3#
40±30
93±42#
216±40
223±41
630±417
577±331*
(*)p<.05; (#)p< 0.001, PTX vs C
Prescribed drugs, respectively in PTX and C, were: Vitamin D (61 vs 64%); Phosphate binders (88 vs 75%) and Calcimimetic (13 and 35%). Notably, Calcitriol and Ca based binders in PTX, and Paricalcitol and Sevelamer in C, were the most frequently prescribed drugs.
PTX has a low prevalence in Italy, and mainly involves relatively young, females and long-term haemodialysis patients. In these patients PTH values are mostly low and therapeutic choices are accordingly different. Different hard outcomes can be hypothesized.