Lung (2014) 192:719–727
DOI 10.1007/s00408-014-9616-3
 

Relationship of Serum Gamma-Glutamyltransferase Levels with Pulmonary Function and Chronic Obstructive Pulmonary Disease

Hyun-Woo Kim • Seock-Hwan Lee • Duk-Hee Lee
 

Abstract

Background Gamma-glutamyltransferase (GGT) levels within the normal reference range, possibly a biomarker of
oxidative stress and/or exposure to various environmental chemicals, are associated with pulmonary function. However, it is unclear whether it is totally independent of cigarette smoking. Also, the potential interaction between
serum GGT and cigarette smoking has not ever been evaluated. Therefore, this study investigated (1) whether
serum GGT levels are associated with pulmonary function and chronic obstructive pulmonary disease (COPD), independent of cigarette smoking, and (2) whether there is any interaction between serum GGT and cigarette smoking status on pulmonary function.

Methods The study subjects were 4,583 participants aged C40 in the 2010–2011 Korean National Health and
Nutrition Examination Survey. The outcomes were pulmonary function (forced expiratory volume in 1 second
[FEV1] and forced vital capacity [FVC]) and spirometrically defined COPD.

Results After adjusting for potential confounders, including cigarette smoking, serum GGT levels were inversely associated with FEV1 and FVC in both genders and positively associated with the risk of COPD in men (all P values \0.01). In men, adjusted odds ratios of COPD were 1.0, 1.69, 1.97, and 2.02 across the quartiles of GGT level (Ptrend = 0.002). However, the associations between serum GGT and pulmonary function seemed to differ depending on the smoking status; inverse associations of GGT with FEV1 % and FVC % were clearly observed only among non-current smokers.

Conclusions In conclusion, in non-smokers serum GGT levels can be used to detect individuals at high risk of
decreased pulmonary function and/or COPD.

Keywords Oxidative stress,  Airway limitation, Smoking,  Air pollution