Analysis Suggests Wealthier Countries Seeing Greater Incidence of AFib Deaths

Markus Sikkel, MBBS, PhD

In most studies, lower socioeconomic status signals increased risk for cardiovascular conditions, but a new study from Europe suggests more wealthy countries had higher rates of atrial fibrillation than less wealthy countries.

An analysis of data from more than 20 European countries, results not only pointed to disparities based on income but also indicated women with atrial fibrillation were more likely to die from the condition than their male counterparts in all countries included in the analysis.

“The ratio of deaths to cases of atrial fibrillation in Europe has not improved over time and, in many European countries, it is actually increasing despite apparent advances in treatment and care,” said Markus Sikkel, MBBS, PhD, adjunct associate professor at the University of Victoria and clinical assistant professor at the University of British Columbia, in a statement. “We think this could be due to differences in lifestyles in wealthier western European countries, where risk factors such as obesity, alcohol consumption and sedentary behavior are more prevalent than in less wealthy, eastern European countries.”

With an interest in further exploring how socioeconomic factors and sex differences impact trends in atrial fibrillation, the current study was designed as a temporal analysis of data from the Global Burden of Disease (GBD) Study database. Launched in 1990, the GBD Study database collects and quantifies information on more than 100 diseases from 8 regions across the world. From this database, investigators obtained data related to atrial fibrillation incidence and mortality from 20 countries in the European Union from 1990-2017.

Investigators use Joinpoint regression analysis to evaluate age-adjusted incidence, mortality, and mortality-to-incidence ratios (MIRs) to assess case fatality rate. For the purpose of the analysis, investigates only included studies with a population greater than 4 million and with data quality rated as 4 stars or greater.

Results of the analyses indicated heterogeneity among incidence and mortality trends through Europe, with Austria, Denmark, and Sweden experiencing peaks in incidence during the middle portion of the study period. The highest mortality rates were seen in wealthier countries and the highest current rates were seen in Sweden for both men and women at 8.38 and 8.88 per 100,000, respectively, in 2017. In all 20 countries studied, MIRS were higher among women than men. Investigators noted this disparity was greatest in Germany and grew over time, from a 43.6% higher rate in women versus men in 1990 to a 74.5% higher rate in women versus men in 2017.

Investigators pointed out the apparent disparities based on socioeconomic status could be driven by multiple factors, including increased life expectancy among patients with comorbid cardiovascular conditions.

"The second important factor, in our view, is that patients in richer countries may survive long enough from other illnesses such as ischemic heart disease and cancer, and then succumb to diseases that are more difficult to treat successfully: heart failure related to atrial fibrillation is one of these,” added Sikkel, in the aforementioned statement. “Another possibility is that atrial fibrillation is less well recognized in poorer countries in a systematic way. We think this is likely to be a real difference and not just an artifact of better documentation in richer nations judging by the findings of previous studies."

This study, “Paradoxical impact of socioeconomic factors on outcome of atrial fibrillation in Europe: trends in incidence and mortality from atrial fibrillation,” was published in the European Heart Journal.