Effect of oral sodium bicarbonate supplementation on progression of chronic kidney disease in patients with chronic metabolic acidosis: study protocol for a randomized controlled trial (SoBic-Study)

摘要

BackgroundOvert chronic metabolic acidosis in patients with chronic kidney disease develops after a drop of glomerular filtration rate to less than approximately 25 mL/min/1.73 m². The pathogenic mechanism seems to be a lack of tubular bicarbonate production, which in healthy individuals neutralizes the acid net production. As shown in several animal and human studies the acidotic milieu alters bone and vitamin D metabolism, induces muscle wasting, and impairs albumin synthesis, aside from a direct alteration of renal tissue by increasing angiotensin II, aldosteron and endothelin kidney levels. Subsequent studies testing various therapeutic approaches in very selected study populations showed that oral supplementation of the lacking bicarbonate halts progression of decline of renal function. However, due to methodological limitations of these studies further investigations are of urgent need to ensure the validity of this therapeutic concept.