Low protein diets in patients with chronic kidney disease: a bridge between mainstream and complementary-alternative medicines?

Abstract

Dietary therapy represents an important tool in the management of chronic kidney disease (CKD), mainly through a balanced reduction of protein intake aimed at giving the remnant nephrons in damaged kidneys a “functional rest”. While dialysis, transplantation, and pharmacological therapies are usually seen as “high tech” medicine, non pharmacological interventions, including diets, are frequently considered lifestyle-complementary treatments. Diet is one of the oldest CKD treatments, and it is usually considered a part of “mainstream” management. In this narrative review we discuss how the lessons of complementary alternative medicines (CAMs) can be useful for the implementation and study of low-protein diets in CKD. While high tech medicine is mainly prescriptive, prescribing a “good” life-style change is usually not enough and comprehensive counselling is required; the empathic educational approach, on which CAMs are mainly, though not exclusively based, may support a successful personalized nutritional intervention.There is no gold-standard, low-protein diet for all CKD patients: from among a relatively vast choice, the best compliance is probably obtained by personalization. This approach interferes with the traditional RCT-based analyses which are grounded upon an assumption of equal preference of treatments (ideally blinded). Whole system approaches and narrative medicine, that are widely used in the study of CAMs, may offer ways to integrate EBM and personalised medicine in the search for innovative solutions respecting individualization, but gaining sound data, such as with partially-randomised patient preference trials.

Dietary protein intake and chronic kidney disease

“…In a meta-analysis of 13 RCTs the mean of protein intake in restricted group was 0.68g/kg/day, which was higher than target values and marginally below the recommended protein intake in the general population. [69] Indeed, even 0.1 to 0.2 g/kg/day reduction in protein intake from baseline appears to result in significant metabolic improvement and longer preservation of kidney health. [2] The VLPD may offer incremental renal protection and beneficial metabolic effects compared to LPD despite a more challenging adherence and somewhat higher risk of PEW (see Figure 1).…”

Dietary Phosphorus Intake and the Kidney

“…Post hoc long-term analyses suggested a trend toward decreased risk of ESRD or death for the low-protein-diet group ( RR = 0.65; 95% CI, 0.38–1.10; P = 0.1). Other randomized studies and meta-analyses of protein restriction trials suggest that LPDs may delay progression to ESRD (9, 33, 55, 56, 125). In a Cochrane Systematic Review , Fouque & Laville (55) examined 10 studies comparing two levels of protein intake in 2,000 nondiabetic adults with moderate to severe CKD for at least 1 year.…”

Green nephrology and eco-dialysis: a position statement by the Italian Society of Nephrology

“…Haemodialysis is probably the most demanding renal replacement technique in terms of needs for transportation, energy and water, while waste management may not be significantly different from PD [31]. The carbon footprint of a treatment goes beyond these issues, and includes others such as drug treatment, whose environmental impact is very difficult to evaluate, but may be as high as that of dialysis disposables [31,122]. Data comparing haemodialysis and peritoneal dialysis is lacking and fail to indicate the true potential for recycling PD materials, which, like urine bags, should probably be classified as urban waste.…”