Promoting smoking abstinence among patients with chronic obstructive pulmonary disease: Initial feasibility

Abstract

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death in the U.S., with the majority of COPD deaths attributable to cigarette smoking. Despite this, individuals with COPD have a higher prevalence of smoking, poorer quit rates, and higher relapse rates compared to smokers without a COPD diagnosis. We examined the feasibility of an incentives-based intervention for producing an initial period of biochemically-verified smoking abstinence among daily smokers with COPD. Participants were randomly assigned to a Contingent (n = 13) or Noncontingent (n = 16) incentives condition and visited the clinic for 14 consecutive days. Contingent participants earned vouchers with monetary value contingent on breath carbon monoxide (CO) levels during Study Days 1-5 and urinary cotinine during Days 6-14. Voucher earnings began at $9.00 and increased by $1.50 with each subsequent negative sample for maximum possible of $362.50. Noncontingent participants received vouchers of comparable value independent of smoking status. Differences between conditions varied across study days for daily smoking abstinence (X² = 45.27, p < 0.0001), CO (F(13, 280) = 1.95, p = 0.025), and cotinine (F(13, 279) = 2.20, p = 0.010), with generally higher rates of abstinence and lower CO and cotinine levels observed in the Contingent vs. Noncontingent conditions. Results from this randomized pilot study support the potential efficacy of an incentives-based intervention for reducing cigarette smoking among individuals with COPD. Further research efforts should seek to promote and evaluate longer-term abstinence and associated changes in respiratory function.

Keywords: Behavioral intervention; Carbon monoxide; Chronic obstructive pulmonary disease; Contingency management; Cotinine; Financial incentives; Smoking; Vouchers.

Fig. 1

Mean daily smoking abstinence (upper panel), mean breath carbon monoxide (CO) levels (middle panel), and mean urinary cotinine levels (lower panel) presented across consecutive study visits during the 14-day study. Abstinence was defined as a CO ≤ 6 ppm during Study Days 1–5 and cotinine ≤ 80 ng/ml for Days 6–14. Data are presented for Contingent (filled symbols) and Noncontingent (open symbols) experimental conditions. Error bars represent SEM. Group × time interactions were significant for all three outcomes (p's < 0.05); asterisks indicate significant group differences (p < 0.05).