Cent un des 107 patients ont une concentration initiale de 25(OH) D abaissée : (moyenne 11,8 ± 8,6 μg/l). À l’issue des trois premiers mois de la phase de correction, la concentration plasmatique du 25(OH) D augmente significativement. Cependant, même avec les doses cumulées les plus élevées – 600 000 UI – seulement 60 % des patients atteignent une concentration plasmatique normale, supérieure à 30 μg/l. Au terme de la phase d’entretien, la concentration du 25(OH) D baisse chez tous les patients. Les concentrations de parathormone, 1-25(OH) D, calcium et phosphore ne varient pas significativement au cours de l’étude. Il n’a pas été noté d’épisode hypercalcémique.
Les doses recommandées de vitamine D2 pour les stades 3 et 4 ne corrigent pas le déficit en 25(OH) D chez les patients hémodialysés. Des études prospectives sont nécessaires pour définir les modalités d’une supplémentation efficace par l’ergocalciférol ou le cholécalciférol.
The plasma concentration of 25(OH) D – calcidiol – is low in most of stage 5 renal patients. Due to the lack of renal 1α-hydroxylase, no supplementation is recommended. However, calcidiol also displays many extraosseous beneficial antiproliferative effects. It may be useful to correct its deficiency in dialysis patients. The efficacy of an oral supplementation for 6 months with ergocalciferol, (Sterogyl®), was evaluated in a monocentric cohort of 107 prevalent hemodialysis patients. Plasma levels of 25(OH) D, parathormone, total and ionized calcium, phosphates, were measured at month 0, 3 and 6 in all patients and plasma levels of 1-25(OH) D at month 0 and 6 in 38 patients with the lowest 25(OH) D levels at baseline. Patients were divided into four groups according to their initial 25(OH) D plasma levels and received ergocalciferol supplementation in accordance to the KDOQI Guidelines for stage 3 and 4 renal patients.
101/107 patients display low levels of 25(OH) D at baseline: mean 11,8 ± 11,6 μg/l (normal > 30 μg/l). At the end of the initial three months correction period, the plasma levels of 25(OH) D rose significantly. However, only 60 % of patients reach a normal plasma concentration of calcidiol with the highest – 600,000 UI – ergocalciferol cumulative dosage. At the end of the three months maintenance period, plasma 25(OH) D concentrations fell in all patients. No significant change was observed in parathormone, calcium, phosphates and 1-25(OH) D plasma levels. There was no hypercalcemic episode.
KDOQI ergocalciferol recommended doses for stages 3 and 4 renal patients did not correct calcidiol deficiency in hemodialysis patients. New prospective studies are required for defining the modalities of an efficient vitamin D supplementation with ergocalciferol or cholecalciferol.