Effect of nonsupplemented low-protein diet on very late stage CRF

Effect of Nonsupplemented Low-Protein Diet on the Initiation of Renal Replacement Therapy in Stage 4 and 5 Chronic Kidney Disease: A Retrospective Multicenter Cohort Study in Japan

OBJECTIVE

In subjects with chronic kidney disease (CKD), the effect of low-protein diet (LPD) is expected to alleviate uremic symptoms. However, whether LPD is effective in preventing loss of kidney function is controversial. The aim of this study was to evaluate the association between LPD and renal outcomes.

METHODS

We conducted a multicenter cohort study of 325 patients who suffered CKD stage 4 and 5 with eGFR ≥10 mL/min/1.73 m,2 between January 2008 and December 2014. The primary diseases of the patients were chronic glomerulonephritis (47.7%), nephrosclerosis (16.9%), diabetic nephropathy (26.2%), and others (9.2%). The patients were divided into four groups, based on the mean protein intake (PI)/day, group 1 (n = 76): PI < 0.5 g/kg ideal body weight/day, group 2 (n = 56): 0.5 ≤ PI < 0.6 g/kg/day, group 3 (n = 110): 0.6 ≤ PI < 0.8 g/kg/day, group 4 (n = 83): PI ≥ 0.8 g/kg/day. Dietary supplementation with essential amino acids and ketoanalogues was not used. The outcome measure was occurrence of renal replacement therapy (RRT) (hemodialysis, peritoneal dialysis, renal transplantation (excluding preemptive transplantation)) and all-cause mortality until December 2018. Cox regression models were used to examine whether LPD was associated with the risk of outcomes.

RESULTS

During a mean follow-up of 4.1 ± 2.2 years. Thirty-three patients (10.2%) died of all causes, 163 patients (50.2%) needed to start RRT, and 6 patients (1.8%) received a renal transplant. LPD therapy of 0.5 g/kg/day or less was significantly related to a lower risk of RRT and all-cause mortality [Hazard ratio = 0.656; 95% confidence interval, 0.438 to 0.984, P = .042].

CONCLUSIONS

These results suggest that non-supplemented LPD therapy of 0.5 g/kg/day or less may prolong the initiation of RRT in stage 4 and 5 CKD patients.

Once-weekly hemodialysis combined with low-protein and low-salt dietary treatment as a favorable therapeutic modality for selected patients with end-stage renal failure: a prospective observational study in Japanese patients

Background

For patients with end-stage renal failure (ESFR), thrice-weekly hemodialysis is a standard care. Once-weekly hemodialysis combined with low-protein and low-salt dietary treatment (OWHD-DT) have been rarely studied. Therefore, here, we describe our experience on OWHD-DT, and assess its long-term effectiveness.

Methods

We instituted OWHD-DT therapy in 112 highly motivated patients with creatinine clearance below 5.0 mL/min. They received once-weekly hemodialysis on a diet of 0.6 g/kg/day of protein adjusted for sufficient energy intake, and less than 6 g/day of salt intake. Serial changes in their clinical, biochemical and nutritional parameters were prospectively observed, and the weekly time spent for hospital visits as well as their monthly medical expenses were compared with 30 age, sex- and disease-matched thrice-weekly hemodialysis patients.

Results

The duration of successfully continued OWHD-DT therapy was more than 4 years in 11.6% of patients, 3 years in 16.1%, 2 years in 24.1% and 1 year in 51.8%. Time required per week for hospital attendance was 66.7% shorter and monthly medical expenses were 50.5% lower in the OWHD-DT group than in the thrice-weekly hemodialysis group (both p < 0.001). Patient survival rates in the OWHD-DT group were better than those in the Japan Registry (p < 0.001). Serum urea nitrogen significantly decreased; hemoglobin significantly increased; and albumin and body mass index were not significantly different from baseline values. In the OWHD-DT patients, serum albumin at 1 and 2 years after initiation of therapy was significantly higher compared with prevalent thrice-weekly hemodialysis patients. Furthermore, residual urine output was significantly higher in the OWHD-DT patients than in those receiving thrice-weekly hemodialysis (p < 0.05). Interdialytic weight gain over the course of the entire week between treatments in patients on OWHD-DT were 0.9 ± 1.0, 2.0 ± 1.3, 1.9 ± 1.2, 1.9 ± 1.5 and 1.8 ± 1.0 kg at 1, 6, 12, 18 and 24 months, respectively, though the weekly weight gain for thrice-weekly hemodialysis group (summed over all 3 treatments) was 8.6 ± 0.63 kg, p < 0.001.

Conclusions

OWHD-DT may be a favorable therapeutic modality for selected highly motivated patients with ESRF. However, this treatment cannot be seen as a general maintenance strategy.

Trial registration

UMIN000027555, May 30, 2017 (retrospectively registered).

Patients' perception on the nutritional therapy for diabetic nephropathy

Low protein diet (LPD) plays an important role in preventing the progression of diabetic nephropathy. However, it is a great burden to the patients. In this paper, we have studied the quality of life (QOL) in such patients.

The study subjects were 59 patients (male 38, female 21) with type 2 diabetes. The patients were classified into tertiles based on their protein intake (g/kg BW). Scores from the diet-related QOL questionnaire were summarized by principal component analysis into four components; mental health, less burden, satisfaction and merit, and less social restriction.

Higher protein intake was associated with less burden and less social restriction. In multiple regression analysis, the significant predictors for the “less burden” component were higher protein intake/BW and estimated glomerular filtration rate (eGFR).

In summary, registered dietitians and clinicians must keep in mind that LPD is a serious burden to the patients and efforts must be made to minimize their burden in order to avoid discontinuation.

A Strict Low Protein Diet during the Predialysis Period Suppresses Peritoneal Permeability at Induction of Peritoneal Dialysis

Background

The factors that predict baseline peritoneal permeability remain largely unknown. We noticed that patients that adhered to a strict low protein diet (LPD) during the predialysis period seldom showed high peritoneal permeability on the peritoneal equilibration test (PET) at the introduction of peritoneal dialysis (PD). Therefore, we investigated whether a strict LPD during the predialysis period affects peritoneal permeability.

Method

We retrospectively analyzed 37 patients that started PD in a single Japanese center. Patients were divided into group A and group B by the median amount of daily protein intake (PI) during the predialysis period using urine collected over 24 hours.

Results

There were no differences between groups A and B in age, gender, proportion of diabetic nephropathy, blood pressure, body mass index, or body surface area. There were also no differences between the groups in laboratory findings, including hematocrit, serum albumin, and serum creatinine. The PETs showed a significantly lower dialysate-to-plasma ratio of creatinine at 4 hours (Cr D/P) for group A than for group B ( p = 0.02). Furthermore, a significant positive correlation between Cr D/P and PI was observed ( r = 0.53, p < 0.01).

Conclusion

It is suggested that a strict LPD during the predialysis period may suppress peritoneal permeability at induction of PD.

Association of socio-psychological factors with the effects of low protein diet for the prevention of the progression of chronic renal failure

OBJECTIVE

Our objectives were to investigate the therapeutic effects of low protein diet (LPD) for chronic renal failure (CRF) in compliant patients with the diet, and to clarify the relationships to the sociopsychological factors.

PATIENTS AND METHODS

Sixty-five patients (47 men and 18 women) with CRF who followed LPD (0.69 g/kg/day) for more than 3 months were recruited in this study. Compliance with the diet therapy was strictly assessed by the patients' dietary records, subsequent interviews regarding the status of daily dietary intake and estimated protein intakes calculated from urinary nitrogen excretion by 24-hour urine collections. The changes of glomerular filtration rate (GFR), serum creatinine (Cr), blood urea nitrogen (BUN), the reciprocal of serum creatinine (1/Cr), scores of Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36), scales of Profile of Mood States (POMS), scores of self-efficacy and social support were investigated.

RESULTS

Decline rate of GFR, elevation of Cr and BUN and reduction in 1/Cr were significantly lower in compliant patients than in noncompliant patients (p<0.05). There were no differences in SF36 scores between compliant and noncompliant patients. The POMS scales of depression/dejection were high in female noncompliant patients compared to other groups of patients (p<0.05). Self-efficacy score was higher in compliant patients than in noncompliant patients (p<0.05). Social support scores were significantly higher in male compliant patients than in others (p<0.05), and both emotional support and behavioral support showed interaction with both gender and compliance with diet therapy (p<0.05).

CONCLUSION

LPD therapy is effective in suppressing the progression of CRF when it is well-adhered to. There are no correlations of this diet therapy to health-related QOL. Social support and high self-efficacy for men and high self-efficacy for women are associated with improvement of the compliance with LPD therapy, leading to good therapeutic effects.