Opportunistic screening versus usual care for diagnosing atrial fibrillation in general practice: a cluster randomised controlled trial

BACKGROUND: Atrial fibrillation (AF) increases the risk of stroke, heart failure, and all-cause mortality. AF may be asymptomatic and therefore remain undiagnosed. Devices such as single-lead electrocardiographs (ECGs) may help GPs to diagnose AF.

AIM: To investigate the yield of opportunistic screening for AF in usual primary care using a single-lead ECG device.

DESIGN AND SETTING: A clustered, randomised controlled trial among patients aged ≥65 years with no recorded AF status in the Netherlands from October 2014 to March 2016.

METHOD: Fifteen intervention general practices used a single-lead ECG device at their discretion and 16 control practices offered usual care. The follow-up period was 1 year, and the primary outcome was the proportion of newly diagnosed cases of AF.

RESULTS: In total, 17 107 older people with no recorded AF status were eligible to participate in the study. In the intervention arm, 10.7% of eligible patients (n = 919) were screened over the duration of the study year. The rate of newly diagnosed AF was similar in the intervention and control practices (1.43% versus 1.37%, P = 0.73). Screened patients were more likely to have comorbidities, such as hypertension (60.0% versus 48.7%), type 2 diabetes (24.3% versus 18.6%), and chronic obstructive pulmonary disease (11.3% versus 7.4%), than eligible patients not screened in the intervention arm. Among patients with newly diagnosed AF in intervention practices, 27% were detected by screening, 23% by usual primary care, and 50% by a medical specialist or after stroke/transient ischaemic attack.

CONCLUSION: Opportunistic screening with a single-lead ECG at the discretion of the GP did not result in a higher yield of newly detected cases of AF in patients aged ≥65 years in the community than usual care. For higher participation rates in future studies, more rigorous screening methods are needed.