Assessment of Serum Retinol-Binding Protein-4 Levels in Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease admitted to Intensive Care Unit

Abstract

Chronic obstructive pulmonary disease (COPD) is a leading and increasing cause of morbidity and mortality worldwide and is characterized by persistent airflow limitation. Inflammation occupies a central role in the pathogenesis of COPD. In addition to local pulmonary inflammation, systemic inflammation is adding to the complexity of the disease, characterized by increased circulating levels of inflammatory cells, cytokines and acute phase proteins that occur in both stable disease and during exacerbations. Patients with acute exacerbations of COPD (AECOPD) have high mortality rates and usually need admission to intensive care units (ICUs). Retinol Binding Protein 4 (RBP4) is a molecule found in the circulation, thought to be secreted mainly by adipose tissue and liver, and is a specific transporter for retinol in the circulation. This study was designed for assessment of serum-retinol binding protein-4 in AECOPD patients at intensive care units and the possibility of its use as a predictive biomarker for mortality in AECOPD. The study was conducted on Ninety persons, divided into 3 groups: Group 1: Forty patients (29 males and 11 females) with AECOPD admitted to ICU at Gamal Abd Elnasser Hospital. Group2: Thirty patients (22 males and 8 females) with stable COPD. Group3: Twenty healthy persons (14 males and 6 females) as a control. All patients' data were collected from Gamal Abd El Nasser Hospital records from December 2014 to December 2015. All COPD patients were classified according to GOLD 2015. They were subjected to full history, clinical examinations, routine investigations, serum RBP4 assessment, APACHE II score and spirometric assessment. The age of all the participants in the study ranged from 54 to 68 years old. There was no significance relation between age and serum RBP4 (rs = -0.098, p = 0.548). AECOPD patients (group 1) admitted to ICU due to many indications as severe dyspnea not responding to emergency therapy, hemodynamic instability or persistent hypoxemia. Samples were collected from the cases within the first day of ICU admission.