A pilot randomised trial to assess the methods and procedures for evaluating the clinical effectiveness and cost-effectiveness of Exercise Assisted Reduction then Stop (EARS) among disadvantaged smokers.

摘要

BACKGROUND: There have been few rigorous studies on the effects of behavioural support for helping smokers to reduce who do not immediately wish to quit. While reduction may not have the health benefits of quitting, it may lead smokers to want to quit. Physical activity (PA) helps to reduce cravings and withdrawal symptoms, and also reduces weight gain after quitting, but smokers may be less inclined to exercise. There is scope to develop and determine the effectiveness of interventions to support smoking reduction and increase physical activity, for those not ready to quit. OBJECTIVE: To conduct a pilot randomised controlled trial (RCT) [Exercise Assisted Reduction then Stop (EARS) smoking study] to (1) design and evaluate the feasibility and acceptability of a PA and smoking-reduction counselling intervention [for disadvantaged smokers who do not wish to quit but do want to reduce their smoking (to increase the likelihood of quitting)], and (2) to inform the design of a large RCT to determine the clinical effectiveness and cost-effectiveness of the intervention. DESIGN: A single-centre, pragmatic, pilot trial with follow-up up to 16 weeks. A mixed methods approach assessed the acceptability and feasibility of the intervention and trial methods. Smokers were individually randomised to intervention or control arms. SETTING: General practices, NHS buildings, community venues, and the Stop Smoking Service (SSS) within Plymouth, UK. PARTICIPANTS: Aged > 18 years, smoking ≥ 10 cigarettes per day (for ≥ 2 years) who wished to cut down. We excluded individuals who were contraindicated for moderate PA, posed a safety risk to the research team, wished to quit immediately or use Nicotine Replacement Therapy, not registered with a general practitioner, or did not converse in English. INTERVENTION: We designed a client-centred, counselling-based intervention designed to support smoking reduction and increases in PA. Support sessions were delivered by trained counsellors either face to face or by telephone. Both intervention and control arms were given information at baseline on specialist SSS support available should they have wished to quit. MAIN OUTCOME MEASURES: The primary outcome was 4-week post-quit expired air carbon monoxide (CO)-confirmed abstinence from smoking. Secondary outcomes included validated behavioural, cognitive and emotional/affective and health-related quality of life measures and treatment costs. RESULTS: The study randomised 99 participants, 49 to the intervention arm and 50 to the control arm, with a 62% follow-up rate at 16 weeks. In the intervention and control arms, 14% versus 4%, respectively [relative risk = 3.57; 95% confidence interval (CI) 0.78 to 16.35], had expired CO-confirmed abstinence at least 4 and up to 8 weeks after quit day; 22% versus 6% (relative risk = 3.74; 95% CI 1.11 to 12.60) made a quit attempt; 10% versus 4% (relative risk = 92.55; 95% CI 0.52 to 12.53) achieved point-prevalent abstinence at 16 weeks; and 39% versus 20% (relative risk = 1.94; 95% CI 1.01 to 3.74) achieved at least a 50% reduction in the number of cigarettes smoked daily. The percentage reporting using PA for controlling smoking in the intervention versus control arms was 55% versus 22%, respectively at 8 weeks and 37% versus 16%, respectively, at 16 weeks. The counsellors generally delivered the intervention as planned and participants responded with a variety of smoking reduction strategies, sometimes supported by changes in PA. The intervention costs were approximately £192 per participant. Exploratory cost-effectiveness modelling indicates that the intervention may be cost-effective. CONCLUSIONS: The study provided valuable information on the resources needed to improve study recruitment and retention. Offering support for smoking reduction and PA appears to have value in promoting reduction and cessation in disadvantaged smokers not currently motivated to quit. A large RCT is needed to assess the clinical effectiveness and cost-effectiveness of the intervention in this population. TRIAL REGISTRATION: ISRCTN 13837944. FUNDING: This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment, Vol. 18, No. 4. See the NIHR Journals Library website for further project information.