RESUMO
Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death worldwide. COPD is often diagnosed late in the disease leading to a delay in management. Notably, tumor necrosis factor-α (TNF-α) polymorphisms may serve an important role in the development of COPD. A single-center, case-control study was conducted to determine the presence of the TNF-α -308 G/A polymorphism among patients diagnosed with COPD presenting with hyperactive airways, patients without COPD presenting with hyperactive airways, and normal study participants without pulmonary comorbidities. Three genotypes: G/G (94%; 157/167), G/A (5%; 9/167) and A/A (1%; 1/167) were detected by quantitative PCR. The present study showed that the presence of the TNF-α -308 G/A polymorphism reduced the odds of having hyperactive airways with COPD by 29.3% and hyperactive airways without COPD by 26.3%. Multinomial logistic regression analysis showed that having the TNF-α -308 G/A polymorphism did not significantly reduce the odds of having hyperactive airways with COPD and without COPD compared to those with the G/G genotype. In conclusion, the presence of the TNF-α -308 G/A gene polymorphism showed no significant association with patients with COPD with or without hyperactive airways. The presence of the TNF-α -308 G/A polymorphism instead had a weak association with the reduction in the development of COPD regardless of the presence or absence of airway hyperactivity.