Chronic disease management for tobacco dependence: a randomized, controlled trial

Abstract

Background: Tobacco dependence disorder is a chronic relapsing condition, yet treatment is delivered in discrete episodes of care that yield disappointing long-term quit rates.

Methods: We conducted a randomized controlled trial from June 1, 2004, through May 31, 2009, to compare telephone-based chronic disease management (1 year; longitudinal care [LC]) with evidence-based treatment (8 weeks; usual care [UC]) for tobacco dependence. A total of 443 smokers each received 5 telephone counseling calls and nicotine replacement therapy by mail for 4 weeks. They were then randomized to UC (2 additional calls) or LC (continued counseling and nicotine replacement therapy for an additional 48 weeks). Longitudinal care targeted repeat quit attempts and interim smoking reduction for relapsers. The primary outcome was 6 months of prolonged abstinence measured at 18 months of follow-up.

Results: At 18 months, 30.2% of LC participants reported 6 months of abstinence from smoking, compared with 23.5% in UC (unadjusted, P = .13). Multivariate analysis showed that LC (adjusted odds ratio, 1.74; 95% CI, 1.08-2.80), quit attempts in past year (1.75; 1.06-2.89), baseline cigarettes per day (0.95; 0.92-0.99), and smoking in the 14- to 21-day interval post-quit (0.23; 0.14-0.38) predicted prolonged abstinence at 18 months. The LC participants who did not quit reduced smoking more than UC participants (significant only at 12 months). The LC participants received more counseling calls than UC participants (mean, 16.5 vs 5.8 calls; P < .001), longer total duration of counseling (283 vs 117 minutes; P < .001), and more nicotine replacement therapy (4.7 vs 2.4 boxes of patches; P < .001).

Conclusion: A chronic disease management approach increases both short- and long-term abstinence from smoking.

Trial registration: clinicaltrials.gov Identifier: NCT00309296.

Figures

Figure 1

Longitudinal care smoking intervention. NRT indicates nicotine replacement therapy.

Figure 2

Diagram of participant flow. LC indicates longitudinal care; UC, usual care.

Figure 3

Graphs of unadjusted rates of prolonged abstinence (A) and 7-day point prevalent smoking abstinence (B) for intent-to-treat for 443 participants from 21 days through 18 months. LC indicates longitudinal care; UC, usual care.

Figure 4

Smoking reduction in the longitudinal care (LC) and usual care (UC) groups: median number of cigarettes per day in nonquitters. At 3, 6, 12, and 18 months, the number missing was 15, 22, 32, and 19 for the LC and 10, 18, 25, and 19 for the UC group, respectively.