Symptomatology, Pulmonary Function and Response, and T Lymphocyte β2‐Receptors During Smoking Cessation in Patients With Chronic Obstructive Pulmonary Disease

Abstract

Study Objectives. To characterize the effect of smoking cessation and nicotine replacement on pulmonary symptomatology, baseline pulmonary function and response to terbutaline, and purified T lymphocyte β2‐receptor regulation; and the relationship between T lymphocyte β2‐receptor density and pulmonary function.Design. Open‐label, longitudinal, 28‐week study.Setting. A university clinical research center.Patients. Eighteen long‐term smokers with mild to moderate chronic obstructive pulmonary disease (COPD) were enrolled and seven completed the study.Interventions. Subjects stopped smoking with the aid of nicotine substitution and behavioral counseling. Pulmonary response (FEVi) to subcutaneous terbutaline and T lymphocyte β2‐receptor density (Bmax) and function (cAMP) were measured prior to smoking cessation (week 0), during nicotine replacement (week 8), and after nicotine cessation (week 28).Measurements and Main Results. Serum cotinine concentrations, plasma epinephrine concentrations, and day and night cough decreased significantly after smoking cessation, whereas basal cAMP concentrations increased (p<0.05). No significant change was seen in baseline FEV1, pulmonary response to terbutaline, or Bmax over the 28 weeks; however, intrasubject changes in Bmax between visits correlated significantly (p<0.05) with intrasubject changes in pulmonary response between visits.Conclusions. Our data indicate that smoking cessation is associated with a significant decrease in the symptomatology of COPD, and that change in T lymphocyte β2‐receptor density is a good marker of change in pulmonary response to β2‐agonists.