Abstract
Unexplained weight loss is common in patients with chronic obstructive pulmonary disease (COPD). Increased circulating of tumor necrosis factor-oc (TNF-oc) and leptin concentrations were reported in weight-losing COPD patients. Leptin is known to play important roles in the control of body-weight and energy expenditure. The aim of this study was to investigate circulating serum leptin and TNF-oc levels in patients with COPD, and to determine whether serum leptin levels are related to body mass index (BMI) or to TNF-oc levels. Serum concentrations of leptin, TNF-oc, albumin and creatinine clearance (CKr) were measured in 32 male patients with COPD and 18 healthy control subjects. Patients with COPD had significantly lower BMI, leptin, albumin and CKr levels than did the control subjects. Serum TNF-oc levels in COPD patients were significantly high compared to the healthy controls. Circulating leptin levels did not correlate with BMI and TNF-oc neither in COPD patients or in healthy controls. These data suggest that circulating leptin is decreased and TNF-oc levels increased in patients with stable COPD. In addition, circulating leptin works independently of the TNF-oc system and does not primarily affect BMI in COPD patients.
Keywords: chronic obstructive pulmonary disease, body mass index, leptin, tumor necrosis factor-a
