The association of metabolic syndrome with adipose tissue hormones and insulin resistance in patients with COPD without co-morbidities.

Chronic obstructive pulmonary disease (COPD) and metabolic syndrome represent common causes of morbidity and mortality in ageing populations. The effect of the co-existence of COPD and metabolic syndrome on adipose tissue hormones and insulin resistance as well as the differences between COPD patients with and without metabolic syndrome have not been adequately studied. The prevalence of metabolic syndrome, based on Adult Treatment Panel III (ATP III) criteria, was evaluated in 114 male patients with COPD without significant co-morbidities. Pulmonary functions tests (PFTs), arterial blood gases, quality of life and BODE index were assessed. Blood samples were obtained for the assessment of adipose tissue hormones and insulin resistance. The overall prevalence of metabolic syndrome was 21%, being more prevalent in earlier stages of COPD. Patients with COPD and metabolic syndrome were younger with higher body-mass index (BMI), had better pulmonary function, less static hyperinflation and air-trapping, better diffusing capacity for carbon monoxide and BODE index. These patients had higher levels of leptin, lower levels of adiponectin and increased insulin resistance, as expressed by HOMA index, compared with patients without metabolic syndrome. Metabolic syndrome was more prevalent in younger patients with less severe COPD. These patients may constitute a specific COPD phenotype with greater leptin to adiponectin imbalance and insulin resistance, despite smaller impairment in PFTs. The prognosis and differences of these patients compared with other COPD phenotypes needs to be determined in prospective studies.