Is the dietary protein restriction achievable in chronic kidney disease? The impact upon quality of life and the dialysis delay

摘要

The possible deleterious effect of meet consumption upon deterioration of renal disease was speculated from Lionel Beale as early as 1869. The first attempt to apply a very low protein diet in humans is attributed to Millard Smith who prescribed a diet consisting of 300 mg protein per day in a volunteer medical student for 24 days. Unfortunately, in early 20^th century, prescribing very low protein diets among patients suffering from renal disease complicated with malnutrition and the medical practice of this era turned to the recommendation of high protein diets because it was believed that protein consumption is coupled with the strength of civilized man. In mid sixties Giordano and Giovanetti introduced low protein diets in the treatment of uremic patients but their efforts did not accepted from the medical community. Meanwhile the evolution of haemodialysis, peritoneal dialysis and transplantation as effective methods of treating end stage renal disease guided doctors and patients far from privative diets in the era of plenty. The rapidly increasing number of end stage renal disease patients needed substitution of renal function produced a tremendous increase of financial burden upon public health system expenditure and alternative measures of therapy, prevention and delaying chronic kidney disease searched. Unfortunately MDRD study failed to show convincing results of food protein restriction and blood pressure lowering in ameliorating deterioration of renal function and the majority of physicians turned to the practice of early dialysis in an attempt to avoid malnutrition. Despite the increasing knowledge and the appliance of certain guidelines in treating end stage renal disease patients, the morbidity and mortality remain high among this population. The search toward other possible toxic substances showed that phosphorus consumption with diet is another dangerous element exerting its deleterious effect in deteriorating renal function as well as increasing morbidity and mortality. Recently published epidemiological data suggest a very poor outcome of elderly patients, older than 80 years of age, undergoing substitution of renal function by dialysis or peritoneal dialysis and a lot of skepticism arise concerning the beneficial effect of diet and a rigorous effort of rehabilitation of these patients instead of substitution of renal function by either method.