Sex-based and age-based differences in participation in an in-hospital atrial fibrillation screening study: a prospective cohort study in Switzerland

Objectives The under-representation of women in cardiovascular clinical trials is well documented but cannot be fully explained by sex-specific differences in disease prevalence. We investigated sex-related and age-related disparities in study participation within an atrial fibrillation (AF) screening study conducted among hospitalised patients. Design Prospective cohort study. Setting In-hospital patients in a single tertiary care centre in Bern, Switzerland. Participants Patients aged 65–84 years evaluated for inclusion in the The SilenT AtRial FIBrillation cohort study, with inclusion stratified by sex and age. Interventions Screening for AF using three consecutive 7-day Holter ECG recordings. Primary and secondary outcome measures Prevalence of clinical and non-clinical exclusion criteria and participation rates among eligible patients, stratified by sex and age. Results Of 11 470 patients evaluated, 10 675 were not enrolled. Clinical exclusion criteria were more prevalent among men than women (60.2% vs 50.5%, p<0.001), with prevalence increasing with age in both sexes. Consequently, fewer men met eligibility criteria compared with women (24.3% vs 32.6%, p<0.001). Among eligible patients, women were less likely to participate than men (20.2% vs 30.0%, p<0.001), and participation declined with advancing age in both sexes. Eligible men aged <75 years demonstrated the highest participation rate (34%). Conclusions Significant sex-dependent and age-dependent disparities exist in both the prevalence of clinical exclusion criteria and participation rates among eligible patients in an AF screening study. These differences should be carefully considered in the design and planning of future clinical studies to improve representativeness.