Study links greater fruit intake to decreased constipation in patients on hemodialysis
Researchers from Brazil found patients on hemodialysis who reported a lower frequency of fruit intake were more likely to have constipation than those who consumed more fruit.
These findings led Rafaela G. dos Santos, RD, of the nutrition department, Centro de Tratamento de Doenças Renais, and colleagues to recommend providing nutritional counseling to these patients, with specific focus on ways to increase fiber intake.
According to the researchers, constipation is often considered a “benign and often self-manageable condition,” causing it to be “overlooked and understudied” as a complication kidney disease.
Further, they wrote that patients on hemodialysis commonly have a low intake of food groups rich in dietary fiber to avoid hyperkalemia. (Healio Nephrology recently covered a study in which the researchers argued that patient dietary resources need to be updated in light of new guidelines suggesting the benefits of plant-based diets; a significant finding of this study was that all of the reviewed resources recommended restricting fruit and vegetable intake).
Though dos Santos and colleagues acknowledge there is no standard recommendation for the management of constipation in chronic kidney disease, gastroenterology guidelines recommend dietary fiber to reduce constipation.
To investigate if greater fruit intake might benefit patients with ESKD, the researchers recruited 305 patients from four dialysis centers. All participants answered a questionnaire which assessed constipation status, use of medications and lifestyle habits. A food frequency questionnaire regarding the main dietary fiber sources (fruits, vegetables, legumes, whole grains and seeds) was then considered, with the researchers estimating the weekly intake frequency through a score (each score point corresponded to one time per week).
Of total participants, 30.5% had constipation, with a univariate analysis revealing these patients were significantly older, with lower literacy, a high prevalence of diabetes and a lower total beverage intake than those without constipation.
Median weekly food frequency scores were 6 for fruits, 6 for vegetables, 3 for legumes, 0 for whole grain and 0 for seeds.
Researchers determined presence of diabetes and fruits intake score to be independent predictors of constipation (odds ratios of 1.96 and 0.95, respectively), leading them to conclude the study provides evidence that a higher intake of fruits has the potential to decrease the occurrence of constipation in patients on hemodialysis.
Elaborating on the findings, dos Santos and colleagues wrote: “Although our patients were counseled to control the intake of some food groups to decrease hyperkalemia risk or treat it, the frequency reported was lower than usually recommended. Epidemiological studies performed in our country in the general population reported a dietary pattern consistent with our results: low consumption of fruits, vegetables, and whole grains leading to inadequate fiber intake.”
Therefore, they suggested that nutritional counseling and recommendations are important, but cultural dietary habits associated with personal preferences and educational status play a significant role in the types of food patients consume.