APPETITE PREDICTS INTAKE AND NUTRITIONAL STATUS IN PATIENTS RECEIVING PERITONEAL DIALYSIS

BACKGROUND

Sub-optimal nutrition status is common amongst patients receiving peritoneal dialysis (PD) and leads to poor clinical outcome. This population experiences multi-factorial challenges to achieving optimal nutritional status, particularly driven by inadequate intake.

OBJECTIVES

The aim of this investigation was to identify factors associated with inadequate protein intake and sub-optimal nutritional status in patients undergoing PD.

DESIGN/PARTICIPANTS

This was a cross-sectional study of 67 adult patients receiving PD (mean age 59 ± 14 years; 57% male) within a single centre. Participants were consecutively recruited and interviewed by renal dietitians, collecting: Subjective Global Assessment (SGA); quality of life (using EQ-5D); dietary intake (via dietary interview); and appetite (using Appetite and Diet Assessment Tool). Participant demographics were obtained via survey or medical charts. Main outcome measures were inadequate dietary protein intake (<1.1 g/kg adjusted body weight/day) and malnutrition (as defined by SGA rating B or C).

RESULTS

Overall, 15 (22%) patients were malnourished and 29 (43%) had inadequate protein intake. Poor appetite (anorexia) was reported in 62% (18/29) of participants with inadequate protein malnourished patients reported anorexia versus 12 (23%) of the well-nourished patients (p = 0.0001).

CONCLUSION

Anorexia was a key risk factor for inadequate protein intake and malnutrition in patients undergoing PD. These findings highlight a need to closely monitor patients with appetite disturbances.

Peritoneal dialysis patients have higher prevalence of gastrointestinal symptoms than hemodialysis patients

OBJECTIVE

Malnutrition is common in dialysis patients and is attributed to decreased food intake, and/or chronic systemic inflammation linked to dialysis-related comorbidities and complications. This study aimed to determine the prevalence of gastrointestinal (GI) symptoms in dialysis patients and whether this impacts food intake.

DESIGN

Cross-sectional study.

SETTING

Tertiary teaching hospital.

PARTICIPANTS

All consenting hospital peritoneal dialysis (PD) and hemodialysis (HD) patients.

METHODS

Patients were interviewed by a dietitian regarding the prevalence and impact of GI symptoms (nausea, vomiting, bloating, early satiety, diarrhea, heartburn, fatigue, and weight changes). Serum levels of albumin were measured, and the use of medication known to cause GI symptoms was recorded.

MAIN OUTCOME MEASURE

Presence of GI symptoms.

RESULTS

The PD (n = 122) and HD (n = 172) groups were similar in age, gender, and presence of diabetes. Serum albumin levels were lower for those on PD compared with HD (3.2 vs. 3.5 g/dL, P < .001). Eighty-five percent of the patients on PD reported at least 1 GI symptom, compared with 51% on HD. Compared with HD, more PD patients reported that GI symptoms were related to the onset of dialysis (55% vs. 12%, P < .001). A greater number of PD patients (compared with HD patients) reported a decrease in food intake (53% vs. 14%, P < .001) and that they had attempted dietary changes to alleviate symptoms (34% vs. 9%, P < .001).

CONCLUSION

These results should influence dietetic educational practice. In addition to the provision of adequate protein and energy, dialysis patients should be counselled regarding the management of GI symptoms and monitored for the prevalence and severity of these symptoms.

Nutrition in patients on peritoneal dialysis

Protein-energy wasting (PEW) is prevalent among patients on dialysis and has emerged as an important risk factor for morbidity and mortality in these patients. Numerous factors, including inflammation, inadequate dialysis, insufficient nutrient intake, loss of protein during dialysis, chronic acidosis, hypercatabolic illness and comorbid conditions, are involved in the development of PEW. The causes and clinical features of PEW in patients on peritoneal dialysis and hemodialysis are comparable; assessment of the factors that lead to PEW in patients receiving peritoneal dialysis is important to ensure that PEW is managed correctly in these patients. For the past 20 years, much progress has been made in the prevention and treatment of PEW. However, the results of most nutritional intervention studies are inconclusive. In addition, the multifactorial and complicated pathogenesis of PEW makes it difficult to assess and treat. This Review summarizes the nutritional issues regarding the causes, assessment and treatment of PEW, with a focus on patients receiving peritoneal dialysis. In addition, an in-depth overview of the results of nutritional intervention studies is provided.

Predictive value of malnutrition markers for mortality in peritoneal dialysis patients

INTRODUCTION

Alterations in nutritional status have been described as important predictors of mortality in patients with chronic kidney disease (CKD). However, the association between multiple markers for nutritional status and the mortality rates of patients with CKD on peritoneal dialysis (PD) has not yet been illustrated in previously published data, particularly by using the new definition of protein energy wasting (PEW).

OBJECTIVE

To evaluate the predictive value of malnutrition markers for mortality rates, on the basis of the PEW definition, of PD patients.

MATERIALS AND METHODS

At the start of PD treatment, the nutritional status of 199 patients (mean age, 56 ± 13.3 years; 53% females) was evaluated. Body mass index (BMI), arm circumference, mid-arm muscle circumference, protein and caloric intake (by using a 3-day food record), and serum albumin were all recorded, as well as a subjective global assessment (SGA) and presence of PEW. Cut-off points were defined on the basis of the consensus of the International Society for Renal Nutrition and Metabolism (albumin, <3.8 g/dL; BMI, <23 kg/m(2); mid-arm muscle circumference, >10% in comparison with the 50th percentile for the reference population; protein intake, <0.8 g/kg/daily; caloric intake, <25 kcal/kg/daily). The data were obtained retrospectively between the years 2001 and 2008 on the basis of routine nutritional evaluation. Patients were monitored for fatal events from all possible causes.

RESULT

The mean BMI for the population was 26.6 ± 5.0 kg/m(2). A median protein intake of 0.94 (0.18 to 4.57) g/kg/daily was reported and 60.3% of the patients reported a protein intake of <0.8 g/kg/daily. With respect to caloric intake, 38.7% of the patients consumed <25 kcal/kg/daily. A median of 3.5 (1.4 to 5.3) g/dL for serum albumin was observed and 29.3% of the patients presented values of <3.8 g/dL. PEW was diagnosed in 17.5% of patients. In the univariate model, being of age >65 years (P = .002), cardiovascular disease (P < .001), diabetes mellitus (P = .02), SGA (P = .02), and albumin (P = .002), were all significant markers for mortality. The presence of patients aged >65 years (P = .02), with diabetes mellitus (P = .057), cardiovascular disease (P = .005), and albumin were considered as independent factors for mortality in this study.

CONCLUSION

SGA, albumin, and PEW were the only nutritional markers found to be associated with mortality in this cohort of PD patients. In the multivariate analysis, after adjusting for classic mortality risk factors, only patients with hypoalbuminemia were found to be at a high risk for mortality at follow-up. These results may be limited by the number of observations and a necessity for confirmation in larger prospective studies.