End-stage renal disease (ESRD) poses a major public health concern in the United States; the standard treatment for ESRD is hemodialysis. Patients receiving maintenance hemodialysis have dietary needs and restrictions, including requirements for increased protein (1.2 g/kg/day) and energy (30-35 kcal/kg/day) intake and restricted intake of phosphorus, sodium, potassium, and/or fluid.
The restrictions add to the difficulty of meeting the protein and energy requirements; other impediments may include postdialysis fatigue, nausea and vomiting, poor appetite, dysgenusia, lack of dietary information, and lack of access to food. The estimated average protein and energy intake of patients receiving hemodialysis is below current recommendations and patients in that population are commonly diagnosed with protein-energy wasting (PEW). Previous studies have also found that energy and protein intake is significantly lower on dialysis treatment days. PEW is known to be associated with poor outcomes, including diminished quality of life and increased mortality rate.
Providing nutrition through food or supplements during hemodialysis sessions has gained support and interest recently. However, despite studies demonstrating potential benefits to quality of life and clinical outcomes, eating during hemodialysis is commonly prohibited or discouraged in dialysis centers in the United States. The practice is discouraged primarily due to various perceived risks, including concern over increased intradialytic postprandial hypotension.
Noting that there are very few data regarding the practice of providing nutrition during hemodialysis, Mun Sun Choi, MS, and colleagues recently conducted a pilot study to examine the effect of high-protein meals provided during dialysis. The primary outcome of interest was the effect on the frequency of symptomatic hypotensive events; secondary outcomes were related to nutritional status, quality of life, and acceptability of meals during dialysis. Results of the study were reported in the Journal of Renal Nutrition [2019;29(2):102-111].
The study intervention was a meal given approximately 1 hour following the start of the dialysis session. A research dietitian designed the meal options, which had consistent nutrient content; patients could choose their meal based on personal preferences. The main items were tuna bowtie salad, chicken salad plate, beef wrap with potato salad, chicken breast sandwich, turkey salad, chicken salad sandwich, vegan bowtie salad, and chicken lettuce salad. Beginning the Wednesday of the first week of the intervention, patients in the intervention group received lunch during their dialysis session; center staff recorded the time of the meal delivery and the return, along with a subjective assessment of the amount of food consumed (0%, 10%, 25%, 50%, 75%, 90%, and 100%).
A total of nine patients in each group (intervention and nonintervention [control]) completed the study and were included in the data analysis. The two arms were similar in baseline characteristics, with the exception of those in the intervention arm being older and having evidence of lower protein intake. The meals were generally well tolerated; one patient in the intervention arm vomited during a meal due to illness and one reported nausea and vomiting prior to three separate dialysis sessions, resulting in decline of meals twice. One patient vomited during a meal reportedly due to the consistency of the food.
Among the patients in the intervention group, there were 19 symptomatic hypotension events in five patients over 25 dialysis sessions in the prestudy period and 19 symptomatic hypotension events in six patients over 25 dialysis sessions per patient during the study period. There was no statistical significance in the difference in symptomatic hypotension event frequency from prestudy to during study period in the intervention group. There were also no statistically significant differences in frequency of hypotension events in the control group. There was no effect on nutritional status.
Of the total cohort of 18 patients, 17 completed the End-of-Study Questionnaire (eight in the intervention arm and nine in the control arm). Overall, patients in both arms had positive attitudes regarding receiving nutritious meals during dialysis; there were no differences in responses between the two groups. In response to the question “how easy do you feel it is for you to eat nutritiously or follow a renal diet?” only 35% of the total cohort responded with “somewhat easy” or “very easy.” When asked “how interested would you be in receiving nutritious meals during dialysis?” 71% responded with “somewhat interested” or “very interested.”
The pilot/feasibility design of the study was cited by the authors as a limitation to the findings. Other limitations cited were the small sample size, the nonrandomization of the two arms, and the uneven distribution between the arms of the baseline characteristics of the patients.
In summary, the researchers said, “These pilot data suggest that meals during hemodialysis do not increase the frequency of symptomatic hypotension events. In addition, patients generally had positive attitudes toward receiving meals and such meals could help educate patients about appropriate food selection. However, changes in nutritional status indicators were not observed. Larger, longer-term, randomized-controlled studies with patients selected for hypoalbuminemia at baseline are needed to confirm these results along with effects on nutritional and clinical outcomes in patients undergoing hemodialysis. Nevertheless, our data do not support the current practice of restricting eating meals during hemodialysis. Our conclusions are in agreement with the new consensus statement on eating during hemodialysis from the International Society of Renal Nutrition and Metabolism.”
- Patients on maintenance hemodialysis are required to increase protein and energy intake and restrict phosphorus, sodium, potassium, and/or fluid intake. Researchers conducted a pilot study to examine the effect of high-protein meals provided during dialysis sessions.
- The primary outcome of interest was the frequency of symptomatic hypotension events; secondary outcomes were nutritional status, quality of life, and acceptability of meals during dialysis.
- There was no statistically significant difference in the change in the frequency of symptomatic hypotension events between the two groups (intervention vs control) from prestudy to during study. There was no effect on nutritional status between the arms; both groups reported positive attitudes toward receiving meals during dialysis.