Short-term effectiveness of smoking-cessation treatment on respiratory function and CEA level

Tobacco smoke contains many chemicals that are harmful and cause carcinogenesis. The aim of this study was to confirm the relationship between smoking and changes in respiratory functional and laboratory parameters comparing, in particular, smoking-cessation treatment's outcomes between smokers who reduce tobacco consumption (reducers) and smokers who quit completely (quitters).

A total of 181 current smokers were prospectively enrolled. All of the participants completed a sociodemographic questionnaire and underwent 3 months of varenicline plus nicotine-replacement therapy combined with basic counseling. Laboratory tests and clinical and lung-function parameters were evaluated at entry and after 3 months of therapy. After 3 months of smoking-cessation treatment, subjects were sorted into two subgroups: quitters and reducers.

After 3 months of combined therapy, 56% of the subjects (101 patients) stopped smoking; the remaining patients reduced. Significant improvements in pulmonary-function tests (especially in the 25-75% forced expiratory volume testing) were recorded. The most significant improvements were obtained in quitters: carboxyhemoglobin was reduced by 1.06%, the average expiratory flow between 25 and 75% of vital capacity increased by 16% from predicted, mean serum CEA level decreased by 1.83 ng/ml, heart rate decreased by approximately 16 beats/min on average and forced 1 s expiratory flow increased by 2.57% from predicted. The Fagerström scores showed a positive correlation with the corresponding blood carboxyhemoglobin levels.

Just 3 months of smoking-cessation treatment achieved significant improvements in lung-function parameters and a decrease in serum CEA, mostly in subjects who totally quit smoking. This result confirms the effectiveness of our smoking-cessation treatment and suggests the utility of the selected parameters as tools to motivate and monitor patients.