Acyl-Ghrelin and Obestatin Plasma Levels in Different Stages of Chronic Kidney Disease

Abstract

This study assessed acyl-ghrelin and obestatin plasma levels in nondialysis chronic kidney disease (CKD) and hemodialysis (HD) patients compared with healthy volunteers. This was a cross-sectional study conducted at Renal Vida Clinic (Rio de Janeiro, Brazil) and Renal Nutrition Ambulatory (Niterói, Brazil). Sixty-four subjects were studied: 29 HD patients (55.4 ± 10.5 years, body mass index [BMI], 24.4 ± 3.9 kg/m(2), 17 men); 19 nondialysis patients (59.8 ± 7.5 years, BMI, 26.3 ± 4.8 kg/m(2), glomerular filtration rate, 28.8 ± 10.5 mL/minute/1.73 m(2), 5 men), and 16 healthy volunteers (53.8 ± 5.4 years, BMI, 24.6 ± 2.7 kg/m(2), 7 men). Acyl-ghrelin and obestatin were assessed using enzyme immunometric assays. Body weight, height, waist circumference (WC), and skinfold were measurement, and body fat percentage, arm muscle area, BMI, and conicity index were calculated. The average daily intake of calories and protein were estimated using a 3-day, 24-hour dietary recall, and the appetite was assessed by the first question of the Hemodialysis Study Appetite Questionnaire. The highest serum acyl-ghrelin (34.1 ± 13.0 pg/mL) and acyl-ghrelin/obestatin ratio (34.0 [6.7-90.2]) were found in nondialysis CKD patients who also presented with the lowest obestatin levels (0.8 [0.30-2.7] ng/mL) when compared with HD patients and healthy volunteers. HD patients presented the highest obestatin plasma levels (3.0 [2.7-3.4] ng/mL) and the lowest acyl-ghrelin/obestatin ratio (P < .05). Obestatin levels inversely correlated with WC (r = -0.6, P < .04) and BMI (r = -0.56, P < .04) in healthy volunteers. Although no correlation was found for appetite and food intake with acyl-ghrelin and obestatin in CKD patients, HD patients have the most important alteration of acyl-ghrelin and obestatin plasma levels and had a more impaired nutritional status than nondialysis CKD individuals.