Everyday Life, Dietary Practices, and Health Conditions of Adult PKU Patients: A Multicenter, Cross-Sectional Study.

BACKGROUND: Only few data on dietary management of adult phenylketonuria (PKU) patients are published. OBJECTIVES: This study aimed to assess living situation, dietary practices, and health conditions of early-treated adult PKU patients. METHODS: A total of 183 early-treated PKU patients ≥18 years from 8 German metabolic centers received access to an online survey, containing 91 questions on sociodemographic data, dietary habits, and health conditions. RESULTS: 144/183 patients (66% females) completed the questionnaire. Compared with German population, the proportion of single-person households was higher (22 vs. 47%), the rate of childbirth was lower (1.34 vs. 0.4%), but educational and professional status did not differ. 82% of the patients adhered to a low-protein diet, 45% consumed modified low-protein food almost daily, and 84% took amino acid mixtures regularly. 48% of the patients never interrupted diet, and 14% stopped diet permanently. 69% of the patients reported to feel better with diet, and 91% considered their quality of life at least as good. The prevalence of depressive symptoms was high (29%) and correlated significantly to phenylalanine blood concentrations (p = 0.046). However, depressive symptoms were only mild in the majority of patients. CONCLUSION: This group of early-treated adult German PKU patients is socially well integrated, reveals a surprisingly high adherence to diet and amino acid intake, and considers the restrictions of diet to their daily life as low.

Low Protein Intake in the Population: Low Risk of Kidney Function Decline but High Risk of Mortality.

OBJECTIVE: This population-based study investigated low protein intake, mortality, and kidney function decline. DESIGN: Observational longitudinal cohort study. SUBJECTS: Target cohort consisted of 4,679 adults participating in 1988-1992 and 2001-2007 examinations of the Gubbio Study (baseline and follow-up). Data collection included overnight urine urea nitrogen (UUN) and other variables at baseline, serum creatinine at baseline and follow-up, and mortality from baseline to follow-up. Three hundred seventy-two persons were excluded for missing data. UUN in the lowest 20% of the distribution was defined as low and used as index of low protein intake. Estimated glomerular filtration rate (eGFR, mL/minute × 1.73 m2) was used as kidney function index. INTERVENTION: None (observational study). MAIN OUTCOME MEASURE: Mortality and eGFR decline are the main outcome measures, and eGFR decline was defined as eGFR change from baseline to follow-up ≤ mean-1 standard deviation (Z-score ≤ -1). RESULTS: Eight hundred seventy-one deaths occurred over 15.9 ± 4.0 years of observation (417 from cardiovascular disease and 276 from neoplastic disease). Low UUN associated with mortality (hazard ratio, HR = 1.31, 95% confidence interval, CI = 1.12/1.53) due to association with mortality from neoplastic disease (HR = 1.33, 95% CI = 1.02/1.76). Mortality-corrected follow-up response rate was 79.9% (n = 2845). Baseline to follow-up eGFR change was -9.9 ± 10.1, and eGFR decline was found in 454 examinees. Low UUN associated with eGFR decline only in subgroup with baseline eGFR <90 (n = 1441, odds ratio = 0.44, 95% CI = 0.22/0.85). Low baseline eGFR interacted with the association between low UUN and eGFR decline (P = .024). CONCLUSION: Low protein intake predicted higher mortality in the whole population and lower incidence of eGFR decline only in subgroup with reduced kidney function.

Dietary interventions for adults with chronic kidney disease.

BACKGROUND: Dietary changes are routinely recommended in people with chronic kidney disease (CKD) on the basis of randomised evidence in the general population and non-randomised studies in CKD that suggest certain healthy eating patterns may prevent cardiovascular events and lower mortality. People who have kidney disease have prioritised dietary modifications as an important treatment uncertainty. OBJECTIVES: This review evaluated the benefits and harms of dietary interventions among adults with CKD including people with end-stage kidney disease (ESKD) treated with dialysis or kidney transplantation. SEARCH METHODS: We searched the Cochrane Kidney and Transplant Specialised Register (up to 31 January 2017) through contact with the Information Specialist using search terms relevant to this review. Studies contained in the Specialised Register are identified through search strategies specifically designed for CENTRAL, MEDLINE, and EMBASE; handsearching conference proceedings; and searching the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov. SELECTION CRITERIA: Randomised controlled trials (RCTs) or quasi-randomised RCTs of dietary interventions versus other dietary interventions, lifestyle advice, or standard care assessing mortality, cardiovascular events, health-related quality of life, and biochemical, anthropomorphic, and nutritional outcomes among people with CKD. DATA COLLECTION AND ANALYSIS: Two authors independently screened studies for inclusion and extracted data. Results were summarised as risk ratios (RR) for dichotomous outcomes or mean differences (MD) or standardised MD (SMD) for continuous outcomes, with 95% confidence intervals (CI) or in descriptive format when meta-analysis was not possible. Confidence in the evidence was assessed using GRADE. MAIN RESULTS: We included 17 studies involving 1639 people with CKD. Three studies enrolled 341 people treated with dialysis, four studies enrolled 168 kidney transplant recipients, and 10 studies enrolled 1130 people with CKD stages 1 to 5. Eleven studies (900 people) evaluated dietary counselling with or without lifestyle advice and six evaluated dietary patterns (739 people), including one study (191 people) of a carbohydrate-restricted low-iron, polyphenol enriched diet, two studies (181 people) of increased fruit and vegetable intake, two studies (355 people) of a Mediterranean diet and one study (12 people) of a high protein/low carbohydrate diet. Risks of bias in the included studies were generally high or unclear, lowering confidence in the results. Participants were followed up for a median of 12 months (range 1 to 46.8 months).Studies were not designed to examine all-cause mortality or cardiovascular events. In very-low quality evidence, dietary interventions had uncertain effects on all-cause mortality or ESKD. In absolute terms, dietary interventions may prevent one person in every 3000 treated for one year avoiding ESKD, although the certainty in this effect was very low. Across all 17 studies, outcome data for cardiovascular events were sparse. Dietary interventions in low quality evidence were associated with a higher health-related quality of life (2 studies, 119 people: MD in SF-36 score 11.46, 95% CI 7.73 to 15.18; I2 = 0%). Adverse events were generally not reported.Dietary interventions lowered systolic blood pressure (3 studies, 167 people: MD -9.26 mm Hg, 95% CI -13.48 to -5.04; I2 = 80%) and diastolic blood pressure (2 studies, 95 people: MD -8.95, 95% CI -10.69 to -7.21; I2 = 0%) compared to a control diet. Dietary interventions were associated with a higher estimated glomerular filtration rate (eGFR) (5 studies, 219 people: SMD 1.08; 95% CI 0.26 to 1.97; I2 = 88%) and serum albumin levels (6 studies, 541 people: MD 0.16 g/dL, 95% CI 0.07 to 0.24; I2 = 26%). A Mediterranean diet lowered serum LDL cholesterol levels (1 study, 40 people: MD -1.00 mmol/L, 95% CI -1.56 to -0.44). AUTHORS' CONCLUSIONS: Dietary interventions have uncertain effects on mortality, cardiovascular events and ESKD among people with CKD as these outcomes were rarely measured or reported. Dietary interventions may increase health-related quality of life, eGFR, and serum albumin, and lower blood pressure and serum cholesterol levels.Based on stakeholder prioritisation of dietary research in the setting of CKD and preliminary evidence of beneficial effects on risks factors for clinical outcomes, large-scale pragmatic RCTs to test the effects of dietary interventions on patient outcomes are required.

A practical approach to low protein diets for patients with chronic kidney disease in Cameroon.

Cameroon is a low-middle income country with a rich diversity of culture and cuisine. Chronic kidney disease (CKD) is common in Cameroon and over 80 % of patients present late for care, precluding the use of therapies such as low protein diets (LPDs) that slow its progression. Moreover, the prescription of LPDs is challenging in Cameroon because dieticians are scarce, there are no renal dieticians, and people often have to fund their own healthcare. The few nephrologists that provide care for CKD patients have limited expertise in LPD design. Therefore, only moderate LPDs of 0.6 g protein per kg bodyweight per day, or relatively mild LPDs of 0.7-0.8 g protein per kg bodyweight per day are prescribed. The moderate LPD is prescribed to patients with stage 3 or 4 CKD with non-nephrotic proteinuria, no evidence of malnutrition and no interrcurrent acute illnesses. The mild LPD is prescribed to patients with stage 3 or 4 CKD with nephrotic proteinuria, non-symptomatic stage 5 CKD patients or stage 5 CKD patients on non-dialysis treatment. In the absence of local sources of amino and keto acid supplements, traditional mixed LPDs are used. For patients with limited and sporadic access to animal proteins, the prescribed LPDs do not restrict vegetable proteins, but limit intake of animal proteins (when available) to 70 % of total daily protein intake. For those with better access to animal proteins, the prescribed LPDs limit intake of animal proteins to 50-70 % of total daily protein intake, depending on their meal plan. Images of 100 g portions of meat, fish and readily available composite meals serve as visual guides of quantities for patients. Nutritional status is assessed before LPD prescription and during follow up using a subjective global assessment and serum albumin. In conclusion, LPDs are underutilised and challenging to prescribe in Cameroon because of weakness in the health system, the rarity of dieticians, a wide diversity of dietary habits, the limited nutritional expertise of nephrologists and the unavailability of amino and keto acid supplements.

North American experience with Low protein diet for Non-dialysis-dependent chronic kidney disease.

Whereas in many parts of the world a low protein diet (LPD, 0.6-0.8 g/kg/day) is routinely prescribed for the management of patients with non-dialysis-dependent chronic kidney disease (CKD), this practice is infrequent in North America. The historical underpinnings related to LPD in the USA including the non-conclusive results of the Modification of Diet in Renal Disease Study may have played a role. Overall trends to initiate dialysis earlier in the course of CKD in the US allowed less time for LPD prescription. The usual dietary intake in the US includes high dietary protein content, which is in sharp contradistinction to that of a LPD. The fear of engendering or worsening protein-energy wasting may be an important handicap as suggested by a pilot survey of US nephrologists; nevertheless, there is also potential interest and enthusiasm in gaining further insight regarding LPD's utility in both research and in practice. Racial/ethnic disparities in the US and patients' adherence are additional challenges. Adherence should be monitored by well-trained dietitians by means of both dietary assessment techniques and 24-h urine collections to estimate dietary protein intake using urinary urea nitrogen (UUN). While keto-analogues are not currently available in the USA, there are other oral nutritional supplements for the provision of high-biologic-value proteins along with dietary energy intake of 30-35 Cal/kg/day available. Different treatment strategies related to dietary intake may help circumvent the protein- energy wasting apprehension and offer novel conservative approaches for CKD management in North America.

A practical approach to low protein diets in Sweden- 45 years of clinical use.

This review provides an overview of the development, implementation and practise of low protein diets (LPD) in Sweden. While the current practice is discussed in general terms emphasizing the interplay between nephrologists and dieticians, the "self-selected" LPD model is explained as a practical approach to facilitated patient's adherence to the nutritional therapy. This model is currently implemented in most clinics of the country and gives considerable flexibility regarding variation in meal planning, food selection, amounts consumed, cooking methods as well as adaptations to day-to-day changes. Current LPD use in Sweden is presented through analysis of the Swedish Renal Registry. Finally two patient cases are illustrated, with examples on their diets, attempts to reduce the protein content to the desired thresholds and their clinical course.

[Diagnosis and treatment of isolated methylmalonic acidemia].

OBJECTIVE: To explore the clinical feature, therapeutic effect and prognosis of isolated methylmalonic acidemia. METHODS: The clinical characteristics, laboratory findings, treatment and outcome of 40 patients were retrospectively analyzed. The main treatment was a low-protein diet supplemented with L-carnitine and special milk free of leucine, valine, threonine and methionine. Vitamin B12 was also given to cobalamin responders. The patients were followed up every 1-3 months. RESULTS: Mutations in the MUT gene were identified in 30 of 33 patients who had accepted DNA testing. Thirty cases were treated and followed up regularly for from 1 month to 8 years. Eight cases had died, 8 had developed normal intelligence, among whom 4 from newborn screening were asymptomatic. Psychomotor developmental delay and mental retardation were present in 14 cases. The propionylcarnitine level, ratio of propionylcarnitine/acetylcarnitine in blood, methylmalonic acid and methylcitric acid levels in urine have decreased significantly, with the median values reduced respectively from 24.15 (7.92-81.02) µmol/L, 1.08 (0.38-6.01), 705.34 (113.79-3078.60) and 7.71 (0.52-128.21) to 10.50 (3.00-30.92) µmol/L, 0.63 (0.25-2.89), 166.23 (22.40-3322.21) and 3.96 (0.94-119.13) (P < 0.05). CONCLUSION: The prognosis of isolated methylmalonic acidemia may be predicted with the enzymatic subgroup, age at onset and cobalamin responsiveness. Outcome is unfavorable in neonatal patients and those who were non-responsive to cobalamin.

[The low-protein diet in chronic kidney disease: still a valid prescription?]. / La dieta ipoproteica nella nefropatia cronica: una prescrizione ancora oggi valida?

Low-protein diets were originally identified as a therapeutic tool to alleviate symptoms and signs of uremia. Their prescription, however, became common in the 1980s to reduce the rate of progression of chronic kidney disease. Since then, several studies of this nonpharmacological intervention have been published. In particular, the Modification of Diet in Renal Disease (MDRD) study, which is a cornerstone of the nephrology literature, was specifically aimed at verifying the effectiveness of low-protein diets; the results, however, were negative. Therefore, the diet issue progressively disappeared from scientific meetings and journals, and as a consequence also its use in clinical practice has diminished. The aim of this paper is to describe the state of the art of low-protein diets almost 15 years from the publication of the MDRD study.

[Less use of alternative treatments by cancer patients in 2002 than in 1999]. / Minder gebruik van alternatieve behandelingen door kankerpatiënten in 2002 dan in 1999.

OBJECTIVE: To determine the use of alternative diets and other alternative treatments in 2002 compared to 1999. DESIGN: Descriptive, questionnaire. METHOD: During the period 13-26 May 2002 a survey was held among all patients visiting the outpatient clinic of the Netherlands Cancer Institute/Antoni van Leeuwenhoek hospital, Amsterdam, the Netherlands. Patients were asked about their current and past use of alternative therapies, their reasons for using these therapies, the way they were informed about these therapies and the expenses involved. The data were compared with the results of a similar study during the period 15-19 March 1999. RESULTS: Of the 729 patients who fulfilled the inclusion criteria, 66 (9%) declined to participate in the study. Of the remaining 663 patients (average age 58.5 years; 28% male), 131 (20%) used an alternative therapy. Of these, 43 patients (7%) used an alternative diet, mainly the Houtsmuller diet, and 88 patients (13%) used a mixture of alternative therapies such as homeopathy, vitamins and herbs. In 1999, 131 patients (30%) used an alternative form of treatment, 51 (13%) of whom used a diet. Of the 43 users of diets in 2002, 11 (26%) believed that the diet would slow down the disease process; in 1999 this was 53% (27/51). Of the 131 users of alternative therapies in 2002, 55% had been made aware of the possibilities of alternative treatments via family and friends. Internet and TV played a minor role as a source of information. 33 (79%) of the diet users informed their physician or nurse about the use. The diet users spent an average of 170 euro per month on their diets. CONCLUSION: Both the percentage of cancer patients who used an alternative diet and the percentage of diet users who believed that a diet could affect the course of the disease were reduced by half compared to three years earlier.

National Kidney Foundation Council on Renal Nutrition survey: past-present clinical practices and future strategic planning.

Early nutritional intervention is thought to play a major role in the preservation of renal function and the overall wellbeing in the renal patient. In preparation for renal replacement therapy (RRT), a consultation with the renal nutritionist to establish a diet consistent with the existing diagnosis may increase the likelihood of reducing cardiovascular risk factors, preventing malnutrition and anemia, and slowing the progression of renal disease, all of which can contribute to positive patient outcomes. In a 1999 United States Renal Data System survey of 3,468 new dialysis patients, 46% indicated that they had not consulted with a dietitian before the initiation of dialysis. To help with establishing education programs, determine staffing guidelines, and planning future endeavors, the National Kidney Foundation Council on Renal Nutrition conducted a survey of their 1,748 members. The survey was designed to assess the current demographic profile and clinical practice elements of practicing renal dietitians. Surveys were distributed as a section of the 1999-2000 winter issue of the CRN Quarterly Newsletter, with 353 of the members responding. Information collected pertained to patient care settings, number of facilities covered, patient age, patient treatment modalities, dietitian contact hours required to effectively educate pre-end-stage renal disease patients on a low-protein diet and to ensure optimal nutrition status for the chronic kidney disease patients. The dietitians of this cohort had practiced dietetics for 14.5 +/- 8.6 years and renal nutrition for 9.15 +/- 6.9 years. The survey data showed a discrepancy between what the clinical practices were in 1999 and what the current recommendations are, based on the Kidney Disease Outcomes Quality Initiatives (K/DOQI) Clinical Practice Guidelines.

Statistical tools for the analysis of nutrition effects on the survival of cohorts.

We discuss various methods which can be employed for the comparative analysis of samples of response curves. In the application discussed here, these curves are hazard functions, each generated by the survival data obtained for a cohort of experimental subjects which are fed a specific diet. It is demonstrated how comparisons of the effects of different diets on survival can be carried out by employing statistical techniques for inference on samples of curves. The methods are illustrated with data on the survival of large cohorts of male and female Mediterranean fruit flies under full diet and under protein deprivation. These statistical methods allow one to investigate differences between the samples of hazard functions generated by the four groups defined by combinations of sex and diet.