In a study recently published in Heart, afib.no network members investigated the incidence of atrial fibrillation (AF) for the entire Norwegian population ≥ 18 years from 2004 to 2014, by age and gender. The prevalence at the end of the study period was also estimated.
Data from the Cardiovascular Disease in Norway (CVDNOR) project with nationwide hospital records spanning from 1994 to 2014, were linked to the Norwegian Cause of Death Registry and vital status from Statistics Norway. Incident cases of AF were defined as an inpatient admission with AF, or death with AF as the underlying cause, and no admissions with AF in the previous 10 years. Age-standardised incidence rates (IR) and incidence rate ratios (IRR) were calculated. Prevalent cases were identified from all patients alive at the end of 2014 with at least one inpatient admission since 1994 or outpatient visit since 2008 (first available).
The researchers found stable incidence rates of AF overall and across most strata of sex and age. However, signs of an increasing incidence of early-onset AF (<45 years) are worrying and need further investigation.
Among adult Norwegians alive at the end of 2014, close to 137 000 had been diagnosed with AF. This corresponds to a prevalence of 3.4%, which is the highest nationwide prevalence reported to date. The prevalence was 2.8% among women and 4.0% among men.
The study was funded by the Norwegian Atrial Fibrillation Research Network (afib.no). It was led by Lars Kjerpeseth and Inger Ariansen at the Norwegian Institute of Public Health, who collaborated with network members at Bærum Hospital, Oslo University Hospital, St. Olav’s Hospital and the universities in Oslo, Trondheim and Bergen. PubMed link here.