- Biochemical parameters: M0, M3, M6, M12: they will include : albumin, pre-albumin, orosomucoïde, C-reactive protein, haptoglobin, natriuresis, 24 hour urinary excretion of creatinine. Four blood samples will be collected and conserved for a posteriori analysis if required (transferrin, retinol binding protein, leptin, hormonal dosages). These analyses will be centralized in Toulouse (Toulouse center will be charged for the shipment of those blood samples).