Effectiveness of two intensive counselling methods for smoking cessation and relapse prevention in persons with coronary heart disease

Cardiovascular disease is the leading cause of death, and coronary heart diseases have an important share in this [1]. Smoking cessation after development of coronary heart disease improves prognosis more than any other treatment and prevents future cardiovascular diseases. Yet, 57% of those who smoked prior to a cardiac event persist in smoking or relapse [2]. Usual smoking cessation care in Dutch cardiology wards -by ward nurses- is not intensive enough [3] and nurses experience difficulties in providing this care[4]. Hence, we need improved intensive and feasible smoking cessation interventions for Dutch cardiac inpatients. Previous studies and reviews [5-10] provide strong indications that intensive counselling interventions including relapse prevention strategies and pharmacotherapy are effective. They are expected to be feasible in practice if carried out by smoking cessation professionals instead of ward nurses and can be provided by telephone of face-to-face. However, such interventions have not yet been tested in cardiac inpatients nor cost-effectiveness is clear. This research proposal aims to provide hospitalized coronary heart disease patients who smoke with proven (cost)effective smoking cessation interventions. However, subgroups may profit more from a different type of intervention and should receive most (cost)effective one. Therefore, two interventions will be compared to each other and to usual care. The interventions mainly consist of intensive counselling by smoking cessation professionals, either by telephone in one intervention and by face-to-face counselling in the other. These comparable interventions differ in delivery mode and duration. Reviews concluded both to be equally effective in general populations [8,9,11] and the Dutch foundation on smoking and health (STIVORO) currently offers them to Dutch public. In our proposal, the interventions start in hospital and continue after discharge. In both interventions, ward nurses start assessing patients’ smoking behaviour followed by providing stop-smoking advice and referral to smoking cessation counselling. In one intervention, we deliver counselling by telephone (TC), in the other face-to-face (FC). Both interventions include nicotine replacement therapy. We study both TC and FC because we have strong indications that persons with high quit motivation profit more from telephone counselling than those with low quit motivation [9]. We expect low SES groups –often less motivated to quit- [12] to profit more from face-to-face counselling than high SES groups [13]. Telephone counselling is expected to be more cost effective in patients with high quit motivation, face-to-face counselling in low SES patients. We propose following studies: STUDY 1: - To assess (differential) effects of TC and FC on smoking cessation and health outcomes in cardiac inpatients. - To assess patients’ appreciation of and experiences with the interventions. Study 1 is an experiment in cardiac wards. We will test effects of TC and FC on smoking cessation against each other and a control group receiving usual care. Based on previous studies (see Power calculations in ‘Strategy’) we in general expect similar effectiveness. We estimate point prevalence abstinence in the experimental groups at 60% at 6 months, against 43% in the control group. After 12 months, we expect 55% abstinence in experimental groups and 35% in the control group. We also expect previously mentioned differential effects in subgroups. Smoking status will be verified by saliva sample on cotinine and intention to treat analyses will be applied. In both experimental groups, we also expect fewer hospital readmissions, cardiac events, mortality and greater improvements in TC/HDL cholesterol ratio and blood pressure. STUDY 2: - To assess incremental cost-effectiveness and budgetary impact of the interventions comparing them to each other and to usual care. Study 2 is an economic evaluation study that will be conducted in the sample of study 1 by comparing the improved outcomes in patients (see study 1) with incremental costs of the interventions and usual care. Resource use will be registered, as well as smoking, cardiac related health care use and productivity losses. Costs per quitter from healthcare and societal perspectives are computed. Modelling will be used to extrapolate outcomes to a lifetime horizon to also assess incremental costs per QALY gained. The budgetary impacts of each intervention will be estimated from insurer and hospital perspectives. STUDY 3: - To assess feasibility of the interventions, experiences of counsellors, nurses and cardiologists in working with them, and detecting relevant conditions for large-scale dissemination. Study 3 is a dissemination study consisting of three sub studies, namely qualitative in-depth interviews followed by two quantitative surveys. The project will result in a dissertation and two interventions ready for large-scale dissemination.