Dietary fibre and mortality risk in patients on peritoneal dialysis

Abstract

Higher fibre intake reduced all-cause and cardiovascular mortality among healthy population, but such data in dialysis patients are limited. We aimed to examine these associations in patients on peritoneal dialysis (PD). This single-centre prospective cohort study enrolled 881 incident PD patients between October 2002 and August 2014. All patients were followed until death, transfer to haemodialysis, renal transplantation or until being censored in June 2018. Demographic data were collected at baseline. Biochemical, dietary and nutrition data were examined at baseline and thereafter at regular intervals to calculate the average values throughout the study. The outcomes were defined as all-cause and cardiovascular death. Cox proportional regression models were applied to explore the relationship between fibre intake and outcomes. Participants with higher fibre intake were more likely to be younger, male and have better residual renal function and serum lipids at baseline. They were prone to maintain better nutrient status, higher blood pressure and lower inflammatory status at baseline and afterwards. Neither baseline nor time-averaged fibre intake did show protective effects on all-cause mortality after multivariate adjustment in the whole cohort. Among non-diabetic PD patients, an independent association between fibre intake and all-cause mortality was found, in which each 1 g/d increase in time-averaged fibre intake correlated to 13 % of reduction in all-cause mortality. We did not observe any benefits of fibre intake in the CVD mortality for both whole cohort and subgroups. The present study revealed that higher dietary fibre intake appeared to have a protective effect on all-cause mortality in non-diabetic PD patients, which suggest that PD patients should be encouraged to eat a diet rich in fibres.

Dietary Fiber and Gut Microbiota in Renal Diets

“…Among nondiabetic peritoneal dialysis patients, fiber intake was inversely associated with all-cause mortality, with a 13% reduction of mortality for each 1 g/day of increased fiber intake [88]. Moreover, in another recent prospective cohort study of 219 prevalent hemodialysis patients, dietary fiber intake was associated with less inflammation, less myocardial hypertrophy, injury, and a reduced risk of major adverse cardiovascular events [89].…”

Fiber intake and health in people with chronic kidney disease

“…Two observational studies in patients on dialysis [ 15 , 66 ] report an inverse association between higher intake of fiber has lower risk of cardiovascular death. However, other studies of patients on PD [ 14 ] or with nondialysis CKD [ 64 ] failed to observe any statistical association. It is difficult to discern whether these differences between studies are explained by low power, differences in the ascertainment of fiber intake from food recalls (and the inherent recall bias of these methods), differences in lifestyle or baseline fiber intake.…”

“…The fiber supplements used in the interventions in the RCTs were: 11, cereals, cookies and snack bars with 23 g/day of added fiber for 4 weeks [ 53 ]; 12, muffins containing pea hull 10 g/day for the first 4 weeks, then pea hull 10 g/day + inulin 15 g/day for 6 weeks [ 42 ]; 14, one symbiotic gel [a mix of probiotics ( Lactobacillus acidophilus and Bifidobacterium lactis Bi-07); 2.31 g of a prebiotic fiber (inulin); 1.5 g of omega-3 fatty acids and vitamins] per day in fasting for 2 months [ 54 ]; 18, about 20 g fructooligosaccharides (FOS) daily for 30 days [ 55 ]; 19, about 10 g/day Inulin-type fructan (ITF) for 12 weeks (12 weeks washout) [ 10 ]; 20, high-fiber diet (12 g fiber per day) for 4 weeks [ 56 ]; 21, resistant starch (9 g/day for the first week, 18 g/day for following weeks) [ 22 ]. References: 1, PREDIMED study [ 57 ]; 2, Fujii study [ 58 ]; 3, Carvalho study [ 59 ]; 4, Gopinath study [ 60 ], 5, Mirmiran study [ 61 ]; 6, ULSAM cohort study [ 62 ]; 7, Chiavaroli study [ 20 ]; 8, Wu study [ 21 ]; 9, Kelly study [ 63 ]; 10, ULSAM cohort study (eGFR <60 mL/min/1.73 m 2 ) [ 64 ]; 11, Salmean study 2013 [ 53 ]; 12, Salmean study 2015 [ 42 ]; 13, Dos Santos study [ 65 ]; 14, Viramontes-Hörner study [ 54 ]; 15, Lin study [ 66 ]; 16, Wang study [ 15 ]; 17, Xu study [ 14 ]; 18, Meksawan study [ 55 ]; 19, Li study [ 10 ]; 20, Sutton study [ 56 ]; 21, Sirich study [ 22 ]; 22, Biruete [ 67 ]; and 23, Yang [ 23 ].…”

“…Similarly, in a study from the NHANES III in the USA, every 10 g/day increase of dietary total fiber intake was inversely related to mortality in participants with CKD (HR = 0.81; 95% CI 0.71–0.93), but no association was found among participants with normal kidney function (HR = 1.04, 95% CI 0.94–1.18) [ 47 ]. However, some studies have failed to observe any link between fiber and the risk of death in patients with HD [ 66 ] or PD [ 14 ].…”

A Mini Review of Plant-Based Diets in Hemodialysis

“…The results of the trial revealed a significant ( p < 0.05) decrease in total cholesterol (TC) level, high-density lipoprotein (HDL) level, and TC:LCL ratio; a significant ( p < 0.05) decrease in total antioxidant capacity and malondialdehyde; and a significant ( p < 0.05) decrease in tumor necrosis factor-α, interleukin-6, interleukin-8, and C-reactive protein in the 10 and 20 g per day fiber supplement groups [4]. A long-term prospective cohort study of patients on peritoneal dialysis ( n = 881) showed an independent association between fiber intake and all-cause mortality wherein each gram per day increase in fiber intake correlated with a 13% reduction in all-cause mortality [14].…”