Effectiveness of combining feedback about lung age or exhaled CO levels with very brief advice (VBA) and support for smoking cessation in primary care compared to giving VBA and support alone

Aim To assess the effectiveness of combining feedback about lung age (LA) or exhaled CO levels with very brief advice to stop smoking (VBA) compared with VBA alone (control). Method Patients from 31 GP practices in N Macedonia, attending primary care appointments, aged >35 who smoked >10 cigarettes per day (cpd) were invited to participate in this RCT. Motivation to quit was not a requirement. The primary outcome was proportion of smokers quit at 4 weeks (biochemically validated 7-day point prevalence abstinence). Poisson regression was used to model the outcomes. Results1368 participants underwent randomization; 452 received VBA+CO, 457 VBA+LA and 459 VBA alone.There was no statistically significant difference in quit rates at 4 weeks for either intervention arms compared with control: VBA+ LA (IRR 0.90 (97.5%CI: 0.35, 2.27) p=0.792), VBA+CO (IRR 1.04 (97.5%CI: 0.44, 2.44) p=0.920). There was a reduction in number of cigarettes smoked per day, adjusting for baseline cpd, which was significant at 4 (IRR 0.94 (95%CI: 0.91,0.98)) and 12 (IRR 0.96 (0.93,0.99)) weeks, although not at 26 weeks (IRR 0.98 (0.94,1.10)) in the VBA+LA arm, compared with control. A significant reduction was also seen in the VBA+CO arm at 4 (IRR 0.94 (0.91,0.97)), 12 (IRR 0.95 (0.92,0.98)) and 26 weeks (IRR 0.94 (0.91,0.98)) compared with control. ConclusionWe found no evidence of a difference in quit rates in smokers who received feedback about LA or CO combined with VBA compared with VBA alone. However, this could be due to lack of power rather than lack of effectiveness. There was evidence of a statistically significant decrease in cpd in those who received feedback about lung age and exhaled CO levels combined with VBA. Differences in smoking behavior, cultural contexts, and environment may influence the translation of these interventions to LMICs where smoking prevalence is high. Implementation Science/Service Development Research Ideas on Respiratory Conditions and Tobacco Dependency Abstract Declaration of Interest The authors declare no conflicts of interest. The NIHR Global Health Research (GHR) Programme is funded through UK Official Development Assistance (ODA) via the Department of Health and Social Care (DHSC).The views expressed in this publication are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care. We gratefully acknowledge IPCRG for introducing us to the primary care networks involved in this study and for its continued facilitation of clinical engagement. References and Clinical Trial Registry Information The study is registered at http://www.isrctn.com(ISRCTN54228638).