Credit: Original article published here.
There is an association between nutritional status and survival among patients on dialysis. However, according to Sara Blumberg Benyamini, PhD, and colleagues, available data focus on patients who have undergone hemodialysis treatment for a minimum of 8 weeks. There are only limited data on the association between clinical outcome and baseline nutritional status at initiation of dialysis and any changes following dialysis initiation.
The researchers conducted a retrospective observational study to examine how baseline nutritional status at the time of dialysis initiation, and the improvement or worsening of nutritional status during the first 3 months of dialysis treatments, affect survival for up to 5 years following the start of renal replacement therapy. Results were reported in the Journal of Renal Nutrition [2022;32(6):758-765].
During the study period of March 1, 2009, to March 1, 2019, 299 patients initiated hemodialysis at the Nephrology and Hypertension Department at the E. Wolfson Medical Center, Holon, Israel. Of those, 287 patients had data on initial nutritional score and first 3 months of nutritional score available.
Nutritional status was determined using the Integrative Clinical Nutrition Dialysis Score (ICNDS) that is based on biochemical assessment of albumin, creatinine, urea, cholesterol, dialysis adequacy, C-reactive protein (CRP), and post-dialysis weight change. Improvement or worsening in nutrition status was monitored by calculating the ICNDS slope for each patient enrolled in the study from three ICNDS values for the first three months in dialysis. The baseline ICNDS and the slope of three subsequent monthly ICNDS values were tested for correlation with the odds of all-cause mortality for each of the first 5 years on dialysis.
Of the overall cohort, median age was 67.6 years and 35.9% were female. A total of 203 of the 287 eligible patients had a baseline ICNDS of ≥75.
Of those with an initial ICNDS <75, diabetes mellitus, cardiovascualr disease, and history of malignancy were significantly more prevalent than among those with an initial ICNDS ≥75 (diabetes mellitus: 55.6% in patients with initial ICNDS ≥75 and 70.7% in those with initial ICNDS <75; P=.022; cardiovascular disease, 55.1% and 68.3%; P=.046; history of malignancy, 19% and 30.5%, respectively; P=.021). Those in the group with initial ICNDS <75 were significantly older than those with ICNDS ≥75 (70.6 years vs 66.5 years; P=.025). The two groups were similar in sex and history of stroke.
Among the patients with initial ICNDS ≥75, the results for albumin, creatinine, urea, and cholesterol were significantly higher than among those with initial ICNDS <75. The level of CRP was significantly higher in the group with initial score <75. The groups were similar in delivered dose of dialysis or percent weight change.
The study examined the association between ICNDS and mortality using the baseline ICNDS and the mortality hazard ratio (HR) for each of the first 5 years on dialysis. There was a significant association between an ICNDS value <75 at initiation of dialysis and increased mortality hazard compared with an ICNDS ≥75 (HR 2.505, 95% C, 1.235-5.079, P=.011 after 1 year; HR 1.798, 95% CI 1.053-3.069, P=.005 after 2 years; HR 1.838, 95% CI 1.200-2.813, P=.005 after 3 years; HR 1.489, 95% CI 1.027-2.159, P=.036 after 4 years; and HR 1.543, 95% CI 1.083-2.198, P=.016 after 5 years of dialysis).
There was an association between a negative slope for the monthly ICNDS values over the first 3 months of dialysis and increased mortality during the 1 to 3 years following dialysis initiation: HR 2.792, 95% CI 1.372-5.681, P=.005 after 1 year; HR 2.194, 95% CI 1.311-3.672, P=.003 after 2 years; and HR 1.732, 95% CI 1.151-2.607, P=.008 after 3 years. There was no association between a negative slope for the first 3 months and increased mortality after 4 or 5 years of dialysis.
There was a significant effect of age at baseline on survival from the second to the fifth year on dialysis: HR 1.039, 95% CI 1.014-1.065, P=.002 after 2 years; HR 1.029, 95% CI 1.010-1.049, P=.003 after 3 years; HR 1.041, 95% CI 1.023-1.059, P=.001 after 4 years; and HR 1.041, 95% CI 1.024-1.058, P=.001 after 5 years.
After the second year of dialysis, diabetes had a significant worsening effect on survival: HR 1.716, 95% CI 0.996-2.958, P=.052 after 2 years; HR 1.660, 95% CI 1.074-2.568, P=.023 after 3 years; HR 1.901, 95% CI, 1.309-2.759 after 4 years; and HR 1.925, 95% CI 1.350-2.745, P=.001 after 5 years.
A history of stroke had a worsening effect on survival after 3 years on dialysis, and cardiovascular disease had a worsening effect on survival after 4 and 5 years on dialysis.
The researchers cited some limitations to the study findings, including the relatively small sample size and the single-center design, the observational approach, and the inclusion of patients who initiated dialysis following treatment for end-stage renal disease as well as those who started dialysis as an emergency treatment.
In summary, the authors said, “The results of our study confirm that the nutritional status at commencement of hemodialysis and the change in nutritional status over the first 3 months on dialysis are major prognostic long-term survival factors. Further research is needed to explore the possible survival implications of transition between nutritional scores and slopes while on dialysis.”
Takeaway Points
- Researchers reported results of a study examining the association between nutritional status at initiation of dialysis and change in nutritional status over the first 3 months and survival after 5 years on dialysis.
- There was an association between nutritional status at the start of dialysis and long-term 5-year survival; a decline in nutritional status over the first 3 months significantly increased the risk of death during the first 3 years on dialysis.
- There was a significant difference in the mortality hazard ratio of patients who started dialysis with an Integrative Clinical Nutrition Dialysis Score (ICNDS) ≥75 and those who started with an ICNDS <75.
