Non-valvular atrial fibrillation (AF) is increasing in the UK with around 200,000 new cases a year. Over the past 13 years the actual standardised AF incidence rose by 17%, a study published in Heart has found.

The authors studied 2.23 million individuals aged ≥ 45 years in the UK Clinical Practice Research Datalink and identified incident non-valvular AF cases between 2001 and 2013. Overall and annual AF incidence rates were calculated and standardised to the UK population.

A total of 91,707 patients with incident AF were found. The overall standardised AF incidence rate was 6.7 (95% CI: 6.7-6.8) per 1,000 person-years, increasing exponentially with age, and was higher in men of all ages.

There was also a small increase in the standardised incidence of AF from 5.9 (5.8-6.1)/1,000 person-years in 2001 to 6.9 (6.8-7.1)/1,000 person-years in 2013. This was mainly due to patients aged ≥ 80 years with a non-primary hospital discharge diagnosis of AF.

Rates of AF in Caucasian patients were almost double those in Asian and Black patients. Standardised incidence rates of AF were:

• Caucasian patients 8.1 (8.1-8.2)/1,000 person-years

• Asian patients 5.4 (4.6-6.3)/1,000 person-years

• Black patients 4.6 (4.0-5.3)/1,000 person-years

The incidence of AF in the UK has increased between 2001 and 2013 with around 200,000 new cases annually.

This equates to 17% more cases of new AF during the study period.

The primary drivers for this increase appear to be the ageing population and increases in conditions that may predispose to AF coupled with raised awareness.

A significant proportion of cases (39%) were diagnosed in primary care and exclusion of this data may explain some of the variation in incidence rates observed in previous studies. 

Early diagnosis of AF remains key to instigating effective thromboprophylaxis and reducing the potential morbidity and mortality associated with the thromboembolic complications of this common arrhythmia.

The study authors conclude: ‘Greater awareness of the increasing incidence of AF in the elderly may lead to increased monitoring for new onset AF in elderly patients in primary care settings and when hospitalised for reasons other than AF. This in turn may facilitate earlier institution of therapy to prevent secondary thromboembolism.’

Dr Peter Savill