The contribution of qualitative research in designing a complex intervention for secondary prevention of coronary heart disease in two different healthcare systems

Background: Developing complex interventions for testing in randomised controlled trials is of increasing importance in healthcare planning. There is a need for careful design of interventions for secondary prevention of coronary heart disease (CHD). It has been suggested that integrating qualitative research in the development of a complex intervention may contribute to optimising its design but there is limited evidence of this in practice. This study aims to examine the contribution of qualitative research in developing a complex intervention to improve the provision and uptake of secondary prevention of CHD within primary care in two different healthcare systems.

Methods: In four general practices, one rural and one urban, in Northern Ireland and the Republic of Ireland, patients with CHD were purposively selected. Four focus groups with patients (N = 23) and four with staff (N = 29) informed the development of the intervention by exploring how it could be tailored and integrated with current secondary prevention activities for CHD in the two healthcare settings. Following an exploratory trial the acceptability and feasibility of the intervention were discussed in four focus groups (17 patients) and 10 interviews (staff). The data were analysed using thematic analysis.

Results: Integrating qualitative research into the development of the intervention provided depth of information about the varying impact, between the two healthcare systems, of different funding and administrative arrangements, on their provision of secondary prevention and identified similar barriers of time constraints, training needs and poor patient motivation. The findings also highlighted the importance to patients of stress management, the need for which had been underestimated by the researchers. The qualitative evaluation provided depth of detail not found in evaluation questionnaires. It highlighted how the intervention needed to be more practical by minimising administration, integrating role plays into behaviour change training, providing more practical information about stress management and removing self-monitoring of lifestyle change.

Conclusion: Qualitative research is integral to developing the design detail of a complex intervention and tailoring its components to address individuals' needs in different healthcare systems. The findings highlight how qualitative research may be a valuable component of the preparation for complex interventions and their evaluation.

Qutting and restarting smoking: cohort study of patients with angina in primary care

Objective To examine variations in self-reported smoking habit among a cohort of individuals with chronic coronary heart disease over a five year period. Design Cross-sectional cohort; interviews at baseline, 2 years and 5 years. Setting Primary care. Participants A cross-sectional sample of 688 patients previously diagnosed as having angina, identified from 18 general practices in the Greater Belfast Area; a cohort of 487 were followed for five years. Outcome measures Changes in self-reported smoking habits; breath carbon monoxide measurement. Results Initially 92 of the 487 participants (19%) reported smoking, 34 (27%) subsequently reported non-smoking. Of the 395 self-reported non-smokers at baseline, 21 (5%) subsequently reported smoking. The prevalence of self-reported smoking amongst the cohort was 19% and 15% at two and five years respectively. However, changes in reported smoking habits indicating periods of abstinence and resumption were reported by 55/487 (11%) participants. Of the 21 non-smokers who changed their report, 20 had smoked previously, five reported having stopped for less than one year but nine for more than five years. Of the initial sample twice as many smokers as non-smokers had died by 2 years (10% v 5%; p

Retinal Pigment Epithelial Cell DNA is Damaged by Exposure to Benzo[a]pyrene, a Constituent of Cigarette Smoke.

This study examined the effect of exogenous benzo[ a ]pyrene (BaP), an important constituent of cigarette smoke, on cultured bovine retinal pigment epithelial (RPE) cells. Evidence is presented for its metabolic conversion into benzo[ a ]pyrene diol epoxide (BPDE) and the consequent formation of potentially cytotoxic nucleobase adducts in DNA. Cultured RPE cells were treated with BaP at concentrations in the range of 0–100 µm. The presence of BaP was found to cause inhibition of cell growth and replication. BaP induced the expression of a phase I drug metabolizing enzyme which was identified as cytochrome P450 1A1 (CYP 1A1) by RT–PCR and by Western blotting. Coincident with the increased expression of CYP 1A1, covalent adducts between the mutagenic metabolite BPDE and DNA could be detected within RPE cells by immunocytochemical staining. Additional support for their formation was afforded by nuclease P1 enhanced 32P-postlabelling assays on cellular DNA. Single-cell gel electrophoresis (comet) assays showed that exposure of RPE cells to BaP rendered them markedly more susceptible to DNA damage induced by broad band UVB or blue light laser irradiation. In the case of UVB, this is consistent with the photosensitization of DNA cleavage by nucleobase adducts of BPDE. Collectively, these findings imply that BaP has a significant impact on RPE cell pathophysiology and suggest mechanisms whereby exposure to cigarette smoke might cause RPE dysfunction and cell death, thus possibly contributing to degenerative disorders of the retina.