Effects of smoking cessation and reduction in asthmatics.

The present study examined the effect of smoking reduction and cessation on asthma regulation and biomarkers of exposure to cigarette smoke. In a prospective open design, we allocated 220 asthmatics among three groups: (a) Smoking reduction (reducers), with the aim of smoking fewer than seven cigarettes per day, (b) complete smoking cessation (abstainers), or (c) continuation of usual smoking (continuing smokers). Subjects used nicotine chewing gum or an oral nicotine inhaler to promote reduction and cessation. We monitored changes in the biomarkers carbon monoxide, cotinine, and thiocyanate, and in peak flow, medicine use, bronchial reactivity, and asthma symptoms. The analysis used the three outcome groups, regardless of original allocation to treatment groups. At 4 months, analysis of abstainers (n = 27), reducers (n = 33), and continuing smokers (n = 50) showed marked, statistically significant decreases in expired carbon monoxide of 17 ppm (abstainers) and 15 ppm (reducers); in plasma cotinine of 124 ng/ml (abstainers) and 122 ng/ml (reducers); and in plasma thiocyanate of 5.03 ng/ml (abstainers) and 3.74 ng/m (reducers). For abstainers, we observed improvements in the asthma-specific quality-of-life score, and reductions in self-reported day and night use of rescue beta2-agonists, in doses of inhaled corticosteroids, in daytime asthma symptoms, and in bronchial hyperreactivity. For reducers, smaller improvements occurred for night use of rescue beta2-agonists, doses of inhaled corticosteroids, and bronchial hyperreactivity. Smoking cessation resulted in a marked decrease in three biomarkers of cigarette smoke inhalation and improved asthma regulation, whereas smoking reduction had a less pronounced effect on biomarkers and only a small effect on asthma regulation.

Smoking reduction promotes smoking cessation: results from a double blind, randomized, placebo-controlled trial of nicotine gum with 2-year follow-up.

AIM: To test the effect of nicotine gum and placebo in smokers not motivated or not able to quit smoking with regard to smoking reduction and smoking cessation. DESIGN: This randomized study evaluated nicotine gum versus placebo for up to 1 year in 411 healthy smokers highly motivated to reduce cigarette use. Smoking reduction was defined as self-reported daily smoking less than 50% of baseline and any decrease (1 p.p.m. or more) in carbon monoxide. SETTING: Pulmonary department, Copenhagen, Denmark. FINDINGS: The overall success rate for sustained smoking reduction was significantly higher at all time-points for active versus placebo gum (6.3% versus 0.5% after 24 months). Nicotine gum achieved significantly higher point prevalence cessation rates than placebo at 12 and 24 months [11.2% versus 3.9% (odds ratio = 3.1; 95% CI, 1.4-7.2 and 9.3% versus 3.4% (odds ratio = 2.9; 95% CI, 1.2-7.1), respectively]. There was a linear relationship between decrease in number of daily cigarettes and decrease in plasma cotinine, exhaled carbon monoxide and plasma thiocyanate, with significantly greater reduction in the nicotine gum group after 4 and 12 months (maximum treatment duration) but not after 24 months. The decrease in toxin intake was smaller than the decline in daily cigarette consumption, suggesting that compensatory smoking occurred. CONCLUSIONS: Nicotine gum promoted cessation in this population of smokers unwilling to quit. Among reducers, the toxin intake correlated with reduced cigarette consumption although some compensatory smoking occurred.

Moxonidine versus placebo as an aid in smoking cessation.

This study assessed the effects of moxonidine as an aid in smoking cessation in 166 heavily addicted smokers who were motivated to quit smoking completely. Recruitment was via advertisement. Patients were randomly allocated to receive double-blind placebo or moxonidine (0.1 mg once or twice daily) for 6 weeks. Brief counseling was provided. An encouragement letter was sent prior to the quit date. Success was defined as not smoking any cigarettes during weeks 3 - 6, an expired carbon monoxide level of < 10 ppm, and a plasma cotinine level of < 25 ng/ml. The study failed to demonstrate a statistically significant effect for moxonidine on either nicotine withdrawal symptoms or smoking cessation. Reported side effects were not different with moxonidine than with placebo, however. Copyright 2000 John Wiley & Sons, Ltd.