Marta Nazha

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

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.

Patient Survival and Costs on Moderately Restricted Low-Protein Diets in Advanced CKD: Equivalent Survival at Lower Costs?

The indications for delaying the start of dialysis have revived interest in low-protein diets (LPDs). In this observational prospective study, we enrolled all patients with chronic kidney disease (CKD) who followed a moderately restricted LPD in 2007–2015 in a nephrology unit in Italy: 449 patients, 847 years of observation. At the start of the diet, the median glomerular filtration rate (GFR) was 20 mL/min, the median age was 70, the median Charlson Index was 7. Standardized mortality rates for the “on-diet” population were significantly lower than for patients on dialysis (United States Renal Data System (USRDS): 0.44 (0.36–0.54); Italian Dialysis Registry: 0.73 (0.59–0.88); French Dialysis Registry 0.70 (0.57–0.85)). Considering only the follow-up at low GFR (≤15 mL/min), survival remained significantly higher than in the USRDS, and was equivalent to the Italian and French registries, with an advantage in younger patients. Below the e-GFR of 15 mL/min, 50% of the patients reached a dialysis-free follow-up of ≥2 years; 25% have been dialysis-free for five years. Considering an average yearly cost of about 50,000 Euros for dialysis and 1200 Euros for the diet, and different hypotheses of “spared” dialysis years, treating 100 patients on a moderately restricted LPD would allow saving one to four million Euros. Therefore, our study suggests that in patients with advanced CKD, moderately restricted LPDs may allow prolonging dialysis-free follow-up with comparable survival to dialysis at a lower cost.

Eco-dialysis: the financial and ecological costs of dialysis waste products: is a ‘cradle-to-cradle’ model feasible for planet-friendly haemodialysis waste management?

BACKGROUND Approximately 2 million chronic haemodialysis patients produce over 2,000,000 tons of waste per year that includes about 600,000 tons of potentially hazardous waste. The aim of the present study was to analyse the characteristics of the waste that is produced through chronic haemodialysis in an effort to identify strategies to reduce its environmental and financial impact. METHODS The study included three dialysis machines and disposables for bicarbonate dialysis, haemodiafiltration (HFR) and lactate dialysis. Hazardous waste is defined as waste that comes into contact with bodily fluids. The weight and cost of waste management was evaluated by various policies of differentiation, ranging from a careful-optimal differentiation to a careless one. The amount of time needed for optimal management was recorded in 30 dialysis sessions. Non-hazardous materials were assessed for potential recycling. RESULTS The amount of plastic waste that is produced per dialysis session ranges from 1.5 to 8 kg (from 1.1 to 8 kg of potentially hazardous waste), depending upon the type of dialysis machine and supplies, differentiation and emptying policies. The financial cost of waste disposal is high, and is mainly related to hazardous waste disposal, with costs ranging from 2.2 to 16 Euro per session (2.7-21 USD) depending on the waste management policy. The average amount of time needed for careful, optimal differentiation disposal is approximately 1 minute for a haemodialysis session and 2 minutes for HFR. The ecological cost is likewise high: less than one-third of non-hazardous waste (23-28%) is potentially recyclable, while the use of different types of plastic, glues, inks and labels prevents the remaining materials from being recycled. CONCLUSION Acknowledging the problem of waste management in dialysis could lead to savings of hundreds of millions of Dollars and to the reuse and recycling of hundreds of tons of plastic waste per year on a world-wide scale with considerable financial and ecological savings.

Calcium-phosphate and parathyroid intradialytic profiles: A potential aid for tailoring the dialysate calcium content of patients on different hemodialysis schedules

Severe hyperparathyroidism is a challenge on hemodialysis. The definition of dialysate calcium (Ca) is a pending issue with renewed importance in cases of individualized dialysis schedules and of portable home dialysis machines with low‐flow dialysate. Direct measurement of calcium mass transfer is complex and is imprecisely reflected by differences in start‐to‐end of dialysis Ca levels. The study was performed in a dialysis unit dedicated to home hemodialysis and to critical patients with wide use of daily and tailored schedules. The Ca‐phosphate (P)‐parathyroid hormone (PTH) profile includes creatinine, urea, total and ionized Ca, albumin, sodium, potassium, P, PTH levels at start, mid, and end of dialysis. “Severe” secondary hyperparathyroidism was defined as PTH > 300 pg/mL for ≥3 months. Four schedules were tested: conventional dialysis (polysulfone dialyzer 1.8–2.1 m2), with dialysate Ca 1.5 or 1.75 mmol/L, NxStage (Ca 1.5 mmol/L), and NxStage plus intradialytic Ca infusion. Dosages of vitamin D, calcium, phosphate binders, and Ca mimetic agents were adjusted monthly. Eighty Ca‐P‐PTH profiles were collected in 12 patients. Serum phosphate was efficiently reduced by all techniques. No differences in start‐to‐end PTH and Ca levels on dialysis were observed in patients with PTH levels < 300 pg/mL. Conversely, Ca levels in “severe” secondary hyperparathyroid patients significantly increased and PTH decreased during dialysis on all schedules except on Nxstage (P < 0.05). Our data support the need for tailored dialysate Ca content, even on “low‐flow” daily home dialysis, in “severe” secondary hyperparathyroid patients in order to increase the therapeutic potentials of the new dialysis techniques.