Background: Orexin-A is a neuropeptide that regulates excitement, alertness and appetite.
Aim of the work: To study the plasma level of orexin-A in patients with COPD during acute exacerbation and its relation with both body mass index and body fat percentage in these patients.
Subjects, methods: This study included 80 subjects who were classified into two groups: Group (I): included 50 patients with COPD in acute exacerbation. Group (II): included 30 apparently healthy subjects as a control group. Plasma orexin-A levels, body mass index (BMI), body fat percentage (BFP), oxygen saturation (SaO2), partial pressure of arterial oxygen (PaO2) and partial pressure of arterial carbon dioxide (PaCO2) were recorded for all patients. Each group was subdivided according to their body mass
index into: underweight with BMI less than 18.5), normal weight (BMI more than 18.5 and less than 25) and overweight (BMI more than or equal 25 and less than 30).
Results: Orexin-A was found to be higher in different COPD weight groups (underweight, normal weight and overweight) when compared with those of control group. Overweight patients in group I had higher values Plasma orexin-A when compared with underweight and normal weight in the same group. Orexin A increased significantly with increased BMI, PaCO2 and BFP and had also significant negative correlation with PaO2 and SaO2.
Conclusion: Patients with COPD during acute exacerbation had higher values of plasma orexin-A when compared with normal subjects and plasma orexin-A correlated positively with BMI and BFP in these patients.