Nutrition and chronic kidney disease

Abstract

The incidence of malnutrition disorders in chronic kidney disease (CKD) appears unchanged over time, whereas patient-care and dialysis techniques continue to progress. Despite some evidence for cost-effective treatments, there are numerous caveats to applying these research findings on a daily care basis. There is a sustained generation of data confirming metabolic improvement when patients control their protein intake, even at early stages of CKD. A recent protein-energy wasting nomenclature allows a simpler approach to the diagnosis and causes of malnutrition. During maintenance dialysis, optimal protein and energy intakes have been recently challenged, and there is no longer an indication to control hyperphosphatemia through diet restriction. Recent measurements of energy expenditure in dialysis patients confirm very low physical activity, which affects energy requirements. Finally, inflammation, a common state during CKD, acts on both nutrient intake and catabolism, but is not a contraindication to a nutritional intervention, as patients do respond and improve their survival as well as do noninflamed patients.

Association of Circulating Fibroblast Growth Factor-23 with Renal Phosphate Excretion among Hemodialysis Patients with Residual Renal Function

“…Considering the wide variety of Chinese food as well as poor accuracy of diet diaries recorded by patients, we used an alternative method instead of dietary interview to estimate phosphate intake (mg/d), which was equal to the protein intake (g/d) multiplied by 15 (mean 15 mg Pi/g protein) (15,16). The normalized protein equivalent nitrogen appearance (nPNA) was chosen as a surrogate of dietary protein intake (17,18).…”

Assessment of preoperative and postoperative prealbumin in thoracic surgery – a two months experience in a Romanian university hospital / Evaluarea preoperatorie şi postoperatorie a prealbuminei în chirurgia toracică - experiența de 2 luni a unui spital universitar din România

“…It has been previously postulated that a level lower than 15 mg/dl, and certainly lower than 11 mg/dl, significantly increases the prognostic risk and requires nutritional intervention and monitoring of prealbumin levels (24). Other authors cite a serum level below 30 mg/dl as suggestive for malnutrition in patients undergoing haemodialysis (25), while a large study identified that prealbumin levels less than 20 mg/dl in dialysis patients were associated with a higher death rate even in patients with normal albumin levels (26). One study found that serum prealbumin level of ≤20 mg/dl was found to determine increased risk for postoperative infections and need for longer intubation time in patients undergoing cardiac surgery (27).…”

Role of Fermentable Carbohydrate Supplements in the Course of Uremia

“…In practice, in patients who are pre-dialysis and treated by a maintenance method, a protein supply lower than 0.6 g/kg/day has been proposed in association with KAs supplementation (El Nahas & Coles, 1986). However, the risk of protein malnutrition, and the constraints inherent to this supplementation led to recommend a moderate dietary protein supply of about 0.8 g/kg/day (Klahr et al, 1994 ;Tom et al, 1995 ;Levey et al, 1996a;Dumler, 2011;Fouque et al, 2011a). In dialysis patients, the protein restriction question is more complex because there is a aggravated risk of protein-caloric undernutrition with an increased morbidity and mortality (30% of the dialysis patients) (Parker et al, 1983;Young et al, 1991).…”

“…This leads to a rejection of protein restriction with, as a result, a proposed supply in the 1 to 1.2 g/kg/day range (Bergström, 1995 ;Cianciaruso et al, 1995 ;Qureshi et al, 1998 ;Antunes et al, 2010). However, it is still uncertain whether this policy is enough in order to equilibrate the N balance in these patients since there is a proportional relationship between the protein supply and the rate of N catabolism as it is estimated by the PCR (protein catabolism rate) (Movilli et al, 1993 ;Harty et al, 1994;Fouque et al, 2011a). The protein-caloric undernutrition observed in dialysis patients is often linked to a deficient supply (Ikizler et al, 1995 ;Pollock et al, 1997, Kalantar-Zadeh, 2003, which is itself often linked to a depressed appetite (Bergström, 1995;Van Der Eijk & Farinelli, 1997).…”

“…Another approach was to use a supplementation of essentials AAs or keto acids (KAs) (Giovannetti, 1989;Lin, 2009), however, the use of these KAs was not particularly convincing (Klahr, 1994;Aparicio et al ., 2009). Studies in CRF patients (randomized trial or not) reported that starting a restriction of dietary protein and phosphate early in the course of CRF has a considerable influence on the rate of progression of this disease (Mitch, 1991 ;Levey et al, 1996aLevey et al, , 1996bWilliam & Maroni, 1998 ;Mackenzie & Brenner, 1998, Garneata & Mircescu, 2010Kalista-Richards, 2011;Fouque et al, 2011a). In experimental models, dietary protein restriction reduces the load of N metabolism end-products for excretion, limits the adaptive changes in remnant nephrons, and slows the tendency to renal disease progression (Hostetter, 1986).…”