INTRODUCTION AND AIMS
Protein-energy malnutrition (m) in outpatients with CKD is an extremely important problem but is not well recognized and the criteria for diagnosis are arbitrary and not universal. The purpose of this study was to evaluate in patients with different degree of CKD the prevalence of malnutrition and inflammation and their modifications in the time using a novel score derived from standard nutritional parameters.
160 patients with chronic kidney disease and free protein-energetic intake were enrolled and subdivided according to GFR calculated from MDRD: stage II, n=23 (M 15 F 8 mean age 59± 19 yrs); stage III, n=69 (M 45 F 24 mean age 63± 15 yrs); stage IV, n=56 (M 36 F 21 mean age 71± 16 yrs); stage V, n=12 (M 7 F 4 mean age 70± 10 yrs).
For each patients we considered: age, cardiovascular disease (CVD), C-reactive protein (CRP), albumin, total lymphocytes, total cholesterol, Body Max Index (BMI), Subjective Global Assessment (SGA) and analysis of body composition derived from Bioelectrical Impedance Analysis: PA=Phase Angle, FM=Fat mass, FFM=Free Fat Mass, BCM=Body Cell Mass, BCMI=Body Cell Mass Index.
Each subject was assigned to a diet according to the stage of CKD
(protein range 0.6-0.8 g/kg of ideal body weight) .
Patients were followed according to the guidelines of the Italian Society of Nephrology (SIN)
(GFR 23 – 55 mL/m 4 months; GFR 15 – 25 mL/m 3 months; GFR < 15 mL/m 45 days).
CRITERIA FOR DIAGNOSIS OF MALNUTRITION
The criteria for diagnosis of malnutrition are arbitrary and not universal. In this study we used the SGA plus the standard nutritional parameters and processed a model for the diagnosis of malnutrition, assigning a score for the different degree of malnutrition (table 3,4,5). Figure 1
Figures 2, 3, 4, 5
Stage of CKD significantly correlated with:
SGA p<0.001; Lymphocytes p<0.05; BMI p<0.005; BCM p<0.001;BCMI p<0.005; FFM p<0.005; FM p<0.005; PA p<0.001
See Figure 6.
Our results indicate:
• the high prevalence of malnutrition is observed in outpatients with CKD, mainly in stage IV-V with a high percentage of p at risk of malnutrition in stage II (78%);
• high prevalence of inflammation is observed in CKD patients, mainly in stage IV and V, but no correlation is detected with the degree of malnutrition;
• with specific nutritional intervention, malnutrition is improving in time;
• BIA represents an attractive clinical tool to detect impairment of body composition from the early stages of CKD;
• our malnutrition score has proved to be an useful, simple and valid tool to identify not only malnourished patients but also those at risk of malnutrition.