Correlation Among Levels Of Serum Leptin, Myostatin, TNF-α, Nutrition Status And Prolonged Weaning Of COPD Patients In RICU

AbstractBackground Background Chronic obstructive pulmonary disease (COPD) withrespiratory failure in patients with invasive mechanical ventilation often occurprolonged weaning, which lead to a series of clinical problems, such as high medicalexpenses, prolonged hospitalization, increased mortality and so on. Prolonged weaningmay be related with factors as ventilation mode, parameters, weaning mode andseverity of diseases, especially nutritional status. Serum leptin, myostatin and TNF-awas considered related to development and occurrence of COPD. This study focused onCOPD patients with respiratory failure and prolonged weaning in respiratory intensivecare unit (RICU), detected these patients with serum leptin, myostatin, TNF-a levelsand nutritional status, defined clinical characteristics of prolonged weaning anddifferent impacts by diverse nutrition supports in these patients.Objectives 1. To discuss the risk factors of patients with COPD in RICU whosemechanical ventilation duration was more than 7 days,14 days and 21 days separately.2. To study the correlation between the levels of serum leptin, myostatin, TNF-a ofCOPD patients with respiratory failure and prolonged weaning in RICU.3. Differentnutrition effects on prolonged weaning of COPD patients with respiratory failure inRICU.Methods 1. We random collected 63 patients with COPD and respiratory failure metthe diagnostic criteria and received invasive mechanical ventilation in Jan.2006-Dec.2007 admission on RICU. Analyzed characteristics of patients in stable stage ofdisease, admission and hospitalization in RICU by t-test, x2 test, and logistic regressionanalysis.2. We random collected 108 patients with COPD respiratory failure met thediagnostic criteria and received invasive mechanical ventilation in Jan.2006-Jul.2010admission on RICU. Divided 46 cases into normal weaning group and 62 cases intoprolonged weaning group according to mechanical ventilation duration, while collected20 patients with COPD and respiratory failure without mechanical ventilation ascontrol group. Measured body mass index (BMI), percentage of ideal bodyweight(IBW%), percentage of fat(fat%), triceps skin-fold thickness (TSF), mid-upperarm muscle circumference (MAMC), total protein(TP), albumin(ALB), prealbum(PA), total lymphocytes count(TLC), and determined levels of serum leptin, myostatin,TNF-a of every group by ELISA to reveal correlation among serum leptin, myostatin.TNF-a levels and prolonged weaning of respiratory failure COPD patients in RICU.3.Selected 62 cases in prolonged weaning group above, randomly divided 20 cases eachgroup into A(Enteral nutrition, EN) group, B (Parenteral nutrition, PN)group, and 22cases into C (PN+EN) group. Respectively measured follow indices before and after 8,15 days of continuous nutrition support treatment:BMI, TP, ALB, PA, transferrin,hemoglobin and TLC, while determined levels of serum leptin, myostatin and TNF-aby ELISA, analyzed and compared clinical nutrition indices, immune index andweaning instances.Results 1.63 patients with COPD need mechanical ventilation were selected, inwhich 26 patients’mechanical ventilation duration was less than 7 days, whosemechanical ventilation duration more than7,14 or 21 days were respectively 20,8 and 9cases. There was no significant relationship with duration of mechanical ventilation,community-acquired pneumonia, baseline pulmonary function test results on admission,and blood gas analysis. Ventilator associated pneumonia(VAP) (OR:5.8; 95%, CI:2-22,P=0.013) acted as independent predictor of mechanical ventilation duration morethan7days; VAP was also a risk factor of mechanical ventilation duration more thanl4days (OR:15; 95%, CI:4-70,P=0.001); mechanical ventilation duration more than21days was mainly related with acute physiology and chronic healthevaluationⅡ(APACHE II) scores (OR:1.7;95%, CI:1-1.5, P=0.002) and albuminlevels(OR:0.5,95% CI:0.27-0.61, p=0.006).2. Nutrition indices of prolonged weaninggroup with COPD in RICU:BMI, IBW%, fat%, TSF, MAMC, TP, ALB, PA and LYMwere all significantly lower than the normal weaning group and control group, serumleptin of prolonged weaning group[(8.68±1.47)μg/L] was higher than normal weaninggroup[(5.99±2.07)μg/L] and control group[(6.01±1.92)μg/L] (P<0.01), TNF-aplasmaconcentration of normal weaning group[(3.70±0.24)ng/L] was markedly higher than thenormal weaning group[(1.50±0.54)ng/L] and control group[(1.30±0.72) ng/L] (P<0.01), and TNF-a concentration difference of the normal weaning group and controlgroup without significance(P>0.05); myostatin of prolonged weaning group[(8.68±1.47)ng/L] was higher than normal weaning group[(5.99±2.07)ng/L] and controlgroup[(6.01±1.92)ng/L] (P<0.01), myostatin concentration difference of the normal weaning group and control group without significance(P>0.05); Serum leptin of prolonged weaning group was significantly negative related with other nutrition indices except TLC and PA, TNF-a was significantly negative related with all nutrition indices, and myostatin had no significant relation with all nutrition indices.3. Measured indices before nutritional support and after 8 days of continuous nutritional support:No significant difference in BMI before and after treatment or among three groups, but the tips were BMI improved after treatment, group C was of the most obvious. Hb of three groups increased slightly with no significant difference after treatment (P> 0.05); The TP or PA difference of group A and C compared with before treatment and after treatment of group B was statistically significant (P<0.05); ALB of three groups was increased after treatment, but of no significant differences (P> 0.05)compared with before treatment; TLC, CD4, CD8, CD4/CD8 of group A, B increased after treatment, with no statistical significance compared with before treatment; TLC, CD4, CD8, CD4/CD8 of group C had statistical significance between before and after treatment (P <0.05); serum leptin, TNF-a levels of three groups were decreased before and after treatment, but only comparison before and after treatment of group C and with group A, B after treatment was statistically significant (P<0.05), and myostatin of the three groups had no significant changes before and after treatment (P> 0.05).Conclusion 1. Severity of disease on admission of RICU, VAP emergence after admission and ALB level were major determinants of invasive mechanical ventilation duration of patients with COPD and respiratory failure.2. Malnutrition of prolonged weaning group was more obviously compare with normal weaning group(P<0.05), levels of serum leptin, myostatin and TNF-a of these patients were higher than control group, and serum leptin, myostatin were related with nutrition indices, it meant high levels of serum leptin, myostatin and TNF-a might be related with disease aggravation and malnutrition of prolonged group.3. The three methods of PN, EN and PN+EN could improve nutrition status and immune function, PN+EN was more effective to make weaning faster and reduce levels of serum leptin and TNF-a.