Registry-based studies of atrial fibrillation from Sweden and Denmark, 2000–2014

<p><b>Objectives:</b> We have noticed an increasing number of publications in relation to atrial fibrillation (AF) based on Swedish and Danish health care registries and therefore found it of interest to perform a systematic review of study aims, data sources, exposures, outcomes, journal impact factor, and citation statistics.</p> <p><b>Materials and methods:</b> We searched PubMed from 2000 to 31 December 2014. We included publications which were entirely or partly based on administrative registries and clinical quality databases, and where AF defined the study population or constituted the study exposure or outcome.</p> <p><b>Results:</b> Our review returned 1445 studies, of which 173 met the criteria for inclusion in the reviews. We noticed an abundant diversity in study aims, data sources, exposures, and outcome. The annual number of publications increased from 1 to 50. The mean (range) and median journal impact factor in the year of publication was 6.9 (0.8–51.7) and 5.7. The total cumulated number of citations up to the end of 2014 for all 173 publications was 3721, and the mean (range) and median cumulated number of citations per publication was 22.4 (0–250) and 6.0, respectively.</p> <p><b>Conclusions:</b> The number of registry-based studies on AF reported from Sweden and Denmark increased substantially from 2000 to 2014, had a great diversity, were well cited and have added information to the understanding of AF epidemiology.</p>