Patient characteristics and risk factors of participants and non-participants in the NOR-COR study.

OBJECTIVES

We aim to compare patient characteristics and coronary risk factors among participants and non-participants in a survey of CHD patients.

METHODS

A cross-sectional study explored characteristics and risk factors in patients hospitalized for acute myocardial infarction and/or revascularization. Study data collected from hospital medical records were compared between participants (n = 1127, 83%) and non-participants (n = 229, 16%), who did not consent to participation in the clinical study.

RESULTS

Non-participants showed statistically higher prevalence of women (28% versus 21%), ethnic minorities (6% versus 3%), patients living alone (26% versus 19%), depression (19% versus 6%), anxiety (9% versus 3%), hypertension (54% versus 43%) and diabetes (24% versus 17%). Significantly higher multi-adjusted odds ratios were found for Charlson comorbidity index 3.4 (95% confidence interval (CI), 2.8, 4.3) and depression 14.5 (4.4, 121.5) in non-participants.

CONCLUSIONS

Non-participants do have higher prevalence of important coronary risk factors compared to participants, and risk factor control may thus be overestimated in available prevention studies. Patients with somatic comorbidity and depression appear to be at particular risk of non-participation in the present study. New strategies accounting for the causes of nonadherence are important to improve secondary prevention in CHD.