Is UCP2 gene polymorphism associated with decreased resting energy expenditure in nondialyzed chronic kidney disease patients?

OBJECTIVE: The deletion/deletion (del/del) polymorphism of uncoupling protein 2 (UCP2) was associated with decreased energy expenditure in diabetic and obese patients. There is evidence of decreased resting energy expenditure (REE) in chronic kidney disease (CKD) patients not yet on dialysis. However, whether REE is associated with the UCP2 polymorphism was not previously investigated in this population. This study evaluated whether the del/del polymorphism of the UCP2 gene is associated with lower REE in nondialyzed CKD patients. DESIGN: This was a cross-sectional study. PATIENTS AND METHODS: Forty-four nondialyzed CKD patients (29 male; aged 52 +/- 12 years; creatinine clearance, 37 +/- 13 mL/min/1.73 m(2) [values are mean +/- SD unless otherwise noted]) were included. Their REE was assessed by indirect calorimetry, and body composition by bioelectrical impedance. High-sensitivity C-reactive protein (hs-CRP) was also evaluated. The insertion/deletion (ins/del) polymorphism of the UCP2 gene was determined in all participants. To test whether the deletion/deletion (del/del) polymorphism of the UCP2 gene was associated with lower REE, the REE of carriers of the del/del genotype (n = 24; group Del) was compared with that of carriers of the insertion and ins/del genotype (n = 20; group Ins). MAIN OUTCOME MEASURE: The main outcome measure was REE. RESULTS: The REE of group Del was similar to that of the group Ins (1379 +/- 239 kcal/day vs. 1360 +/- 289 kcal/day, respectively, P = NS). This result was maintained even after the REE was adjusted for lean body mass by analysis of covariance. In addition, in a multiple-regression analysis using REE as the dependent variable, only lean body mass and hs-CRP were significant predictors of REE. CONCLUSION: The results suggest that the del/del polymorphism of the UCP2 gene is not associated with lower REE in nondialyzed CKD patients.

Inflammation is associated with increased energy expenditure in patients with chronic kidney disease.

BACKGROUND: Inflammation, a clinical condition observed in patients with chronic kidney disease (CKD), may be related to increased resting energy expenditure (REE). OBJECTIVES: The main objective was to investigate the relation between inflammation and REE in patients with CKD who are not undergoing dialysis. We also aimed to analyze whether a decrease in C-reactive protein (CRP) would result in a reduction in REE. DESIGN: This study enrolled 132 patients with CKD who were not undergoing dialysis, who had creatinine clearance from 5 to 65 mL.min(-1).1.73 m(-2), and who were 53.6 +/- 16 y old; 82 (62.1%) were men. Twenty-nine patients had clinical signs of infection. REE was measured by using indirect calorimetry, and inflammation was evaluated by using high-sensitivity CRP measurement. Patients were divided according to tertiles of CRP with the following intertertile ranges: first tertile, CRP < or = 0.14 mg/dL (n = 43); second tertile, CRP 0.15-0.59 mg/dL (n = 46); and third tertile, CRP > or = 0.60 mg/dL (n = 43). REE was measured before and after treatment in 10 patients who had inflammation or infection. RESULTS: After adjustment for age, sex, and lean body mass, the REE of the third (1395 kcal/d; P = 0.02) and second (1355 kcal/d; P = 0.04) tertiles was significantly higher than that of the first tertile (1286 kcal/d). In the multiple linear regression analysis (n = 132), the independent determinants of REE were lean body mass, CRP, and age (R2 = 0.55). After treatment of infection in a subgroup of 10 patients, it was observed that a significant reduction in CRP concentration was accompanied by a significant reduction of 174 +/- 165 kcal that accounted for 13% of the initial REE. CONCLUSION: This study showed that inflammation is associated with increased REE in patients with CKD.

Influência da inflamação sobre o gasto energético de repouso de pacientes com doença renal crônica na fase não dialítica / Inflamation is associed with increased energy expanditure in CKD patients

Vários estudos têm mostrado que pacientes com doença renal crônica (DRC) tanto na fase não dialítica quanto na fase dialítica apresentam níveis séricos de proteína C-reativa elevados, caracterizando uma condição inflamatória. Os níveis elevados de PCR estão associados com redução de alguns parâmetros do estado nutricional. A razão para essa associação é multifatorial e inclui fatores que poderiam acelerar o catabolismo protéico e/ou reduzir a ingestão alimentar. Também se pode aventar que o aumento do gasto energético de repouso (GER) esteja envolvido, uma vez que em outras enfermidades já foi demonstrado que níveis elevados de PCR estão associados com aumento do GER. No entanto, essa relação ainda não está bem esclarecida na DRC. Dessa forma, o pressente trabalho tem como objetivo investigar a relação entre inflamação e o GER de pacientes com DRC e analisar o GER após a redução dos níveis de PCR. Para tanto, foram estudados 132 pacientes com DRC na fase não dialítica, sendo que 29 apresentavam alguma infecção associada. Pacientes com diabetes melito e com alteração da função tireiodiana não foram incluídos no estudo. O GER foi avaliado pelo método da calorimetria indireta e a inflamação foi avaliada pela dosagem da PCR pelo método ultra-sensível de quimiluminescência. Os pacientes foram divididos em tercis de PCR, com os seguintes pontos de corte: 1º tercil (PCR <_ 0,14 mg/dL, n=43 ), 2º tercil (0,15 <_ PCR <_ 0,59 mg/dL, n=46), 3º tercil (PCR >_ 0,60 mg/dL, n=43). Além disso, num subgrupo de 10 pacientes o GER foi avaliado pré e pós-tratamento da infecção. Dos 132 pacientes avaliados, 82 eram homens (62,1 por cento), com idade média de 54 ±16 anos e com clearance de creatinina entre 5 a 65 ml,/min/1.73 m2. Em média, os pacientes não apresentavam sinais de desnutrição…(au)