Patterns and trends in atrial fibrillation and atrial flutter incidence rates in G20 countries (1990–2021) and predictions to 2050

Abstract

The long-term trend in atrial fibrillation (AF) and atrial flutter (AFL) incidence has rarely been reported from a global perspective. We aimed to explore the past temporal trends (1990–2021) in AF/AFL incidence in group of 20 countries and to predict future trends (2022–2050). Data on yearly AF/AFL incidence by age group and sex were extracted from the global burden of disease study 2021. Age-standardized incidence rates (ASIR) were computed from 1990 to 2021. The number of new cases and incidence rates were predicted to 2050 using the Bayesian age–period–cohort model. The ASIR for AF/AFL exhibited a slight increasing trend on a global scale from 1990 to 2021, with an average annual percent change of 0.5% (95% confidence interval: 0.5–0.5). Canada had the highest ASIR of AF/AFL (97.53/100,000) and showed a significant declining trend from 1990 to 2021, while the USA and Germany showed a clear upward trend and a “wave-like” upward trend, respectively. Notably, Italy experienced a significant increase in the ASIR of AF/AFL during the COVID-19 pandemic (2019–2021), with an annual percent change of 9.3% (95% confidence interval: 6.6–12.0). The ASIR of AF/AFL in developing countries increased more significantly than in developed countries (ASIR change percentage: 4.79% vs 0.20%). The ASIR of AF/AFL is predicted to remain stable or increase in most countries by 2050. AF/AFL remains a significant public health concern, necessitating the development of more precise strategies for prevention, control, and surveillance, particularly among specific populations and endemic countries.

1. Introduction

Atrial fibrillation (AF) and atrial flutter (AFL) are the most prevalent sustained arrhythmias, constituting a significant public health concern.^[1] In 2019, the global prevalence of AF/AFL was estimated to be 59.7 million, with 4.72 million new cases diagnosed and 315,000 deaths reported.^[2] The incidence of AF/AFL is highest in high-income countries (especially the United States and Canada) and has continued to increase in developing countries (especially China) over the past 20 years.^[3] High systolic blood pressure is the leading risk factor for AF/AFL, accounting for approximately 60% of all cases.^[4] Other identified risk factors include smoking, alcohol abuse, obesity, diabetes mellitus, etc.

Population aging and common modifiable risk factors for AF/AFL (including early intervention and control of high systolic blood pressure, and the increasing prevalence of smoking, alcohol abuse, and obesity) have undergone significant changes in recent decades.^[2] In addition, SARS-CoV-2 infection may increase the burden of AF/AFL.^[5] Within this context, the global burden and trends of AF/AFL may be influenced. Understanding patterns and trends in the context of changing risk factors and predicting future trends in AF/AFL incidence are crucial for prevention, treatment, and guiding resource allocation at the national level. However, extant studies estimating the burden and trends of AF/AFL have typically focused on the national or regional level,^[6–8] specific age groups,^[2,9] or sex differences.^[4,10,11] Few studies have comprehensively analyzed the long-term trends in AF/AFL incidence from a global perspective.

The group of 20 (G20) is an international economic cooperation forum whose members include developed and developing countries, representing nearly two-thirds of the global population.^[12] The G20 countries play an important role in improving global health, as their member countries already face numerous problems related to aging populations and the increased prevalence of noncommunicable diseases. Therefore, we employed data obtained from the global burden of diseases, injuries, and risk factors study (GBD) 2021 to assess the incidence of AF/AFL in G20 countries, and comprehensively explored past temporal trends (1990–2021) and predicted future trends (2022–2050), aiming to illustrate temporal changes and geographical differences in the past and future.

2. Methods

2.1. Data source

The GBD 2021 database, which provides a comprehensive annual assessment of morbidity and mortality estimates for 371 diseases and injuries, and 88 risk factors, for 2 sexes in 204 countries and territories from 1990 to 2021, was used to conduct a comprehensive analysis of trends in AF/AFL. The Global Health Data Exchange query tool (https://vizhub.healthdata.org/gbd-results/) was utilized to obtain the data, which includes annual incident cases and population data with 95% uncertainty intervals, by sex, region, as well as countries from 1990 to 2021. The G20 countries include Argentina, Australia, Brazil, Canada, China, the European Union, France, Germany, India, Indonesia, Italy, Japan, Mexico, the Republic of Korea, the Russian Federation, Saudi Arabia, South Africa, Turkey, the United Kingdom, and the United States of America (USA).

2.2. Definition of AF/AFL

The GBD study encompassed all forms of AF and AFL, including paroxysmal, persistent, and permanent/chronic, as classified according to the 10th edition of the international classification of diseases I48–I48.9.^[13] The detailed case definition of input data for AF/AFL in the GBD study can be found elsewhere^[4]: irregularly irregular RR intervals (in the absence of complete atrioventricular [AV] block); the absence of distinct P waves on the surface ECG; and an atrial cycle length (when visible) that is typically variable and not exceeding 200 ms.

2.3. Statistical analysis

We calculated age-standardized incidence rates (ASIRs) per 100,000 population for AF/AFL based on region-specific, country-specific, and sex-specific annual numbers for 5-year age groups (from 30–34 to 95+ years) using the GBD standard population for selected ages and for truncated age groups (30–59, 60 years and older). The truncated ASIRs were calculated using the following formula:

$$\begin{array}{c}{\displaystyle }\begin{array}{c}{\displaystyle }\mathrm{t}\mathrm{r}\mathrm{u}\mathrm{n}\mathrm{c}\mathrm{a}\mathrm{t}\mathrm{e}\mathrm{d}\mathrm{A}\mathrm{g}\mathrm{e}\mathrm{S}\mathrm{t}\mathrm{a}\mathrm{n}\mathrm{d}\mathrm{a}\mathrm{r}\mathrm{d}\mathrm{i}\mathrm{z}\mathrm{e}\mathrm{d}\mathrm{I}\mathrm{n}\mathrm{c}\mathrm{i}\mathrm{d}\mathrm{e}\mathrm{n}\mathrm{c}\mathrm{e}\\ & {\displaystyle }\mathrm{R}\mathrm{a}\mathrm{t}\mathrm{e}(\mathrm{p}\mathrm{e}\mathrm{r}100,000\mathrm{p}\mathrm{o}\mathrm{p}\mathrm{u}\mathrm{l}\mathrm{a}\mathrm{t}\mathrm{i}\mathrm{o}\mathrm{n})=\frac{{\sum }_{i=1}^A{a}_i{w}_i}{{\sum }_{i=1}^A{w}_i}\times 100,000\end{array}\end{array}$$

where $a_i$ is defined as the incidence rate in the ith age group, and $w_i$ is defined as the number of GBD standard populations in the same age group.

We defined “hotspot countries” as those with an ASIR value >60 in 1990. Heatmaps were produced to illustrate the temporal trends and the variations between countries in the ASIR of AF/AFL in selected countries from 1990 to 2021. The human development index (HDI) is a useful indicator for measuring the globalization of disease. The G20 countries were divided into 2 categories by HDI using a cutoff value of 0.88 (11 high-income countries and 9 middle- and low-income countries).

To quantify the significant changes in the overall trend of ASIR from 1990 to 2021, we used joinpoint regression to calculate the estimated annual percent change (APC) for each identified trend, assuming that there was only 1 segment throughout the entire period of our study to estimate the average annual percentage change (AAPC). The Bayesian age–period–cohort model was applied to predict the ASIR of AF/AFL to 2050. Here, incidence rates were analyzed based on 3 different timescales, including age, period, and cohort. We defined prior distributions for age, period, and cohort effects that smoothed each point on the 2 preceding points (random walk 2) in the Bayesian age–period–cohort model. Joinpoint Regression Program version 5.4.0 (Statistical Research and Applications Branch, National Cancer Institute) was used to analyze the joinpoint regression. Other analyses and data visualization were performed using R version 4.0.0 (R Foundation for Statistical Computing).

3. Results

3.1. Observed trends

Table 1 shows the ASIR of AF/AFL per 100,000 between 1990 and 2021. Canada had the highest ASIR of AF/AFL (97.53/100,000) in 1990, whereas the USA had the highest ASIR (85.89/100,000) in 2021. The majority of countries experienced stable or declining trends in ASIR of AF/AFL between 1990 and 2021. Among these, the most notable decline was observed in Argentina, where the ASIR decreased from 39.72/100,000 in 1990 to 27.45/100,000 in 2021. Conversely, the most significant increase was recorded in the USA, where the rate rose from 72.34/100,000 in 1990 to 85.89/100,000 in 2021. In addition, the ASIR of AF/AFL in both men and women decreased most significantly in Argentina (by 19.22% and 42.09%, respectively). However, the rate increased most significantly in men in Saudi Arabia (by 13.10%) and in women in the USA (by 28.78%).

Table 1.

Trends in incidence rates of AF/AFL among men and women in G20 countries between 1990 and 2021.

Country	Men			Women			Total
	ASIR		Change in rates (%)	ASIR		Change in rates (%)	ASIR		Change in rates (%)
	1990	2021		1990	2021		1990	2021
Global	55.64	55.1	−0.97	44.81	44.79	−0.04	50.04	49.85	−0.38
Europe	75.4	78.59	4.23	54.09	51.32	−5.12	64.35	64.48	0.20
European Union	77.09	81.43	5.63	56.46	53.04	−6.06	66.68	66.96	0.42
France	79.95	70.74	−11.52	53.58	44.78	−16.42	66.59	57.44	−13.74
Germany	97.98	107.73	9.95	59.3	54.01	−8.92	77.45	80.5	3.94
Italy	75.26	73.82	−1.91	69.88	61.96	−11.33	73.43	68.08	−7.29
Russian Federation	53.59	58.58	9.31	41.86	46.03	9.96	47.1	51.7	9.77
Turkey	31.77	32.27	1.57	28.46	19.81	−30.39	29.86	25.46	−14.74
United Kingdom	63.86	63.44	−0.66	39.29	38.71	−1.48	51.29	50.93	−0.70
Oceania	90.98	85.97	−5.51	51.91	58.41	12.52	70.97	71.98	1.42
Australia	90.98	85.97	−5.51	51.91	58.41	12.52	70.97	71.98	1.42
America	87.98	90.15	2.47	55.27	61.87	11.94	70.02	75.16	7.34
Argentina	43.87	35.44	−19.22	35.66	20.65	−42.09	39.72	27.45	−30.89
Brazil	74.57	74.57	0.00	57.67	56.42	−2.17	65.62	64.72	−1.37
Canada	121.72	100.46	−17.47	76.96	56.98	−25.96	97.53	77.94	−20.09
Mexico	66.11	70.86	7.18	57.49	56.17	−2.30	61.65	63.01	2.21
United States of America	95.92	104.51	8.96	53.47	68.86	28.78	72.34	85.89	18.73
Asia	44.38	45.47	2.46	39.61	40.54	2.35	42.14	43.18	2.47
China	39.43	43.45	10.20	37.76	40.01	5.96	39.04	42.14	7.94
India	50.27	50.88	1.21	43.4	45.42	4.65	46.9	48.03	2.41
Indonesia	59.9	62.14	3.74	60.33	61.89	2.59	60.33	62.34	3.33
Japan	47.38	41	−13.47	33.61	20.61	−38.68	40.47	30.8	−23.89
Republic of Korea	54.79	50.48	−7.87	41.19	42.2	2.45	47.81	46.53	−2.68
Saudi Arabia	33.06	37.39	13.10	27.02	30.05	11.21	30.34	34.53	13.81
Africa	48.54	49.9	2.80	44.95	43.32	−3.63	46.44	46	−0.95
South Africa	48.54	49.9	2.80	44.95	43.32	−3.63	46.44	46	−0.95

AF = atrial fibrillation, AFL = atrial flutter, ASIR = age-standardized incidence rate, G20 = group of 20.

Figure 1 presents the temporal trends in ASIRs of AF/AFL in selected countries between 1990 and 2021. In the 20 selected countries, the ASIR of AF/AFL in 1990 was >60 in 10 countries (classified as “hotspot countries”), between 40 and 60 in 6 countries, and <40 in 4 countries. These “hotspot countries” include: European Union, France, Germany, Italy, Australia, Brazil, Canada, Mexico, USA, and Indonesia. Among the “hotspot countries,” Canada had the highest ASIR of AF/AFL (97.53/100,000) and showed a significant declining trend from 1990 to 2021. In contrast, the USA and Germany showed a clear upward trend and a “wave-like” upward trend, respectively, during the same period. Additionally, for other hotspot countries, those countries with an ASIR between 40 and 60, as well as countries with an ASIR below 40 in 1990, the ASIRs of AF/AFL remained relatively stable to 2021.

Figure 1.

Heatmap showing the temporal change in the age-standardized incidence rate (per 100,000 persons) for AF/AFL between 1990 and 2021 in all selected countries. AF = atrial fibrillation, AFL = atrial flutter.

Table 2 presents the joinpoint regression analysis for the ASIRs of AF/AFL. The global ASIR of AF/AFL showed a slight increase between 1990 and 2021, with an AAPC of 0.5% (95% confidence interval [CI]: 0.5–0.5), and presented 3 consecutive periods: an APC of −0.2% (95% CI: −0.3 to −0.1) between 1990 and 1999, an APC of 0.6% (95% CI: 0.5–0.6) between 1999 and 2014, and an APC of 1.4% (95% CI: 1.3–1.4) between 2014 and 2021. The ASIR of AF/AFL remained stable or exhibited a mild upward trend in the majority of countries during the study period. Among them, China demonstrated the most pronounced increase, with an AAPC of 1.5% (95% CI: 1.3–1.6), primarily occurring after 1999. However, Argentina experienced the most pronounced decline, with an AAPC of −1.0% (95% CI: −1.2 to −0.8), mainly occurring between 1996 and 1999, during which the APC was −9.2% (95% CI: −11.1 to −7.3). Notably, Italy experienced a significant increase in the ASIR of AF/AFL during the COVID-19 pandemic (2019–2021), with an APC of 9.3% (95% CI: 6.6–12.0).

Table 2.

Joinpoint analysis for AF/AFL incidence rates in G20 countries, 1990 to 2021.

Country	The whole period		Period 1		Period 2		Period 3
	Period	AAPC	Period	APC	Period	APC	Period	APC
Global	1990–2021	0.5 (0.5–0.5)	1990–1999	−0.2 (−0.3 to −0.1)	1999–2014	0.6 (0.5–0.6)	2014–2021	1.4 (1.3–1.4)
Europe	1990–2021	0.5 (0.4–0.6)	1990–2000	0.5 (0.3–0.6)	2000–2015	0.1 (0–0.2)	2015–2021	1.4 (1.1–1.7)
European Union	1990–2021	0.5 (0.4–0.6)	1990–2000	0.5 (0.4–0.7)	2000–2014	0.1 (0–0.2)	2014–2021	1.4 (1.1–1.6)
France	1990–2021	0.1 (0.1–0.2)	1990–1998	−0.1 (−0.2 to 0)	1998–2011	−0.5 (−0.5 to −0.4)	2011–2021	1.1 (1.0–1.1)
Germany	1990–2021	0.4 (0.1–0.7)	1990–1995	−1.2 (−2.1 to −0.2)	1995–1999	3.4 (1.3–5.6)	1999–2021	0.2 (0.1–0.3)
Italy	1990–2021	0.3 (0.1–0.4)	1990–2004	−1.1 (−1.2 to −0.9)	2004–2019	0.4 (0.3–0.5)	2019–2021	9.3 (6.6–12.0)
Russian Federation	1990–2021	0.8 (0.7–0.8)	1990–2007	1.1 (1.1–1.2)	2007–2018	0.1 (0.1–0.2)	2018–2021	1.1 (0.6–1.5)
Turkey	1990–2021	0.3 (0.1–0.4)	1990–1995	1.1 (0.3–2.0)	1995–2006	−0.7 (−1.0 to −0.5)	2006–2021	0.7 (0.6–0.8)
United Kingdom	1990–2021	0.1 (0.1–0.2)	1990–2000	−0.2 (−0.3 to −0.1)	2000–2010	−1.0 (−1.1 to −0.9)	2010–2021	1.5 (1.4–1.5)
Oceania	1990–2021	0.7 (0.5–0.8)	1990–2005	0.5 (0.3–0.6)	2005–2019	1.2 (1.1–1.3)	2019–2021	−1.2 (−3.2 to 0.9)
Australia	1990–2021	0.7 (0.5–0.8)	1990–2005	0.5 (0.3–0.6)	2005–2019	1.2 (1.1–1.3)	2019–2021	−1.2 (−3.2 to 0.9)
America	1990–2021	0.8 (0.7–0.8)	1990–2000	−0.1 (−0.3 to 0.0)	2000–2016	0.9 (0.9–1.0)	2016–2021	2.1 (1.9–2.4)
Argentina	1990–2021	−1.0 (−1.2 to −0.8)	1990–1996	0.3 (0–0.6)	1996–1999	−9.2 (−11.1 to −7.3)	1999–2021	−0.2 (−0.1 to −7.7)
Brazil	1990–2021	0.8 (0.7–0.8)	1990–2021	0.5 (0.5–0.5)	2010–2019	0.9 (0.8–1.0)	2019–2021	3.1 (2.4–3.9)
Canada	1990–2021	0.3 (0.1–0.5)	1990–2010	−0.3 (−0.4 to −0.3)	2010–2019	2.1 (1.8–2.4)	2019–2021	−1.3 (−3.4 to 0.9)
Mexico	1990–2021	0.9 (0.8–0.9)	1990–1996	−0.1 (−0.2 to 0.1)	1996–2000	0.5 (0.1–1.0)	2000–2021	1.2 (1.2–1.2)
United States of America	1990–2021	1.2 (1.1–1.3)	1990–1999	−0.1 (−0.3 to 0.2)	1999–2017	1.4 (1.3–1.5)	2017–2021	3.1 (2.5–3.8)
Asia	1990–2021	1.1 (1.0–1.1)	1990–1999	−0.1 (−0.2 to 0)	1999–2015	1.4 (1.3–1.4)	2015–2021	2.1 (1.9–2.3)
China	1990–2021	1.5 (1.3–1.6)	1990–1999	−0.4 (−0.7 to −0.1)	1999–2015	2.0 (1.9–2.1)	2015–2021	3.0 (2.7–3.4)
India	1990–2021	0.8 (0.8–0.9)	1990–1999	0.7 (0.6–0.8)	1999–2010	1.1 (1.0–1.2)	2010–2021	0.7 (0.6–0.7)
Indonesia	1990–2021	0.5 (0.5–0.5)	1990–2011	0.3 (0.3–0.3)	2011–2015	0.6 (0.6–0.7)	2015–2021	1.2 (1.2–1.3)
Japan	1990–2021	0.7 (0.6–0.9)	1990–2003	−0.7 (−0.9 to −0.5)	2003–2011	0.4 (0–0.8)	2011–2021	2.9 (2.7–3.1)
Republic of Korea	1990–2021	1.4 (0.9–1.9)	1990–1993	−3.0 (−7.0 to 1.2)	1993–2017	1.3 (1.1–1.4)	2017–2021	5.6 (3.9–7.4)
Saudi Arabia	1990–2021	−0.5 (−0.6 to −0.4)	1990–2004	−0.1 (−0.3 to 0)	2004–2014	−2.0 (−2.2 to −1.8)	2014–2021	0.8 (0.6–1.1)
Africa	1990–2021	0.1 (0–0.1)	1990–2002	−0.2 (−0.3 to −0.2)	2002–2010	0.4 (0.3–0.5)	2010–2021	0.1 (0.1–0.2)
South Africa	1990–2021	0.1 (0–0.1)	1990–2002	−0.2 (−0.3 to −0.2)	2002–2010	0.4 (0.3–0.5)	2010–2021	0.1 (0.1–0.2)

AAPC = average annual percent of change, AF = atrial fibrillation, AFL = atrial flutter, APC = estimated annual percent of change, G20 = group of 20.

Table S1, Supplemental Digital Content 1 lists the changes in the ASIR of AF/AFL from 1990 to 2021 by HDI category. The results show that the ASIR of AF/AFL in middle- and low-income countries increased more significantly than in high-income countries (ASIR change percentage: 4.79% vs 0.20%). Figure 2 shows the temporal trends for the ASIR of AF/AFL by age group, namely the younger group (30–59 years) and older group (>60 years), for the 20 countries categorized by HDI category. In all selected 20 countries, the ASIR was higher among older adults than among younger adults. In addition, the increase in the ASIR of AF/AFL in the younger group was more pronounced than in the older group (ASIR change percentage: 3.97% vs 1.59%), although the ASIR of AF/AFL in both younger and older groups remained stable or increased in most countries (Table S2, Supplemental Digital Content 2). For example, the ASIR increased most significantly in Germany and China in the younger group, and the rate of increase was more than twice that in the older group. However, among older adults, the ASIR of AF/AFL has increased most significantly in the USA, where it is 3 times higher than in younger adults. Figures S1 and S2, Supplemental Digital Content 3 show the ASIR and temporal trends of AF/AFL in females and males, respectively. The ASIR was higher in males than in females.

Figure 2.

Temporal trends in age-standardized incidence rate (per 100,000 persons) of AF/AFL from 1990 to 2021 in both sexes. AF = atrial fibrillation, AFL = atrial flutter.

3.2. Predicted trends

Figure 3 shows the observed and predicted trends in the ASIR of AF/AFL between 1990 and 2050. In Europe, we predict that the ASIR in Germany will increase from approximately 81 per 100,000 people in 2022 to approximately 92 per 100,000 people in 2030, and then remain stable until 2050. The ASIR in France will increase from approximately 57 per 100,000 people in 2022 to approximately 65 per 100,000 people in 2030, and then show a clear downward trend until 2050. The ASIR of AF/AFL in other European countries will remain stable between 2022 and 2050. In some American countries, such as Canada, Brazil, and Argentina, the ASIR of AF/AFL will increase slightly between 2022 and 2050, but the ASIR will remain stable in the United States and Mexico. Several Asian countries, including Indonesia, India, Japan, and Saudi Arabia, have historically low rates of AF/AFL and are projected to remain stable over the next 30 years. However, China and the Republic of Korea are experiencing a different trend, with rates expected to rise from approximately 35/100,000 in 2022 to approximately 45/100,000 in 2050.

Figure 3.

Trends in observed (solid lines) and predicted (dashed lines) age-standardized incidence rates of AF/AFL in selected countries by continent. AF = atrial fibrillation, AFL = atrial flutter.

4. Discussion

To the best of our knowledge, this study represents one of the most comprehensive analyses of observed and predicted trends in AF/AFL incidence globally through 2050, which may motivate experts to reassess the burden of AF/AFL, reevaluate existing prevention measures, and develop more reasonable control strategies. Several key observations can be derived from our study. The ASIR for AF/AFL exhibited a slight increasing trend on a global scale from 1990 to 2021, with an AAPC of 0.5% (95% CI: 0.5–0.5). Two historically high-incidence areas, the USA and Canada, exhibited opposite trends during the study period. The ASIR of AF/AFL in the USA showed a significant upward trend from 1990 to 2021, and the high rate is predicted to persist through 2050. In contrast, the ASIR of AF/AFL in Canada exhibited a declining trend during the study period and is predicted to increase mildly between 2022 and 2050. Notably, Italy experienced a significant increase in AF/AFL ASIR from 2019 to 2021, after which it stabilized through 2050. Moreover, the ASIR of AF/AFL is increasing more significantly in developing countries and among younger populations.

We observed a significant upward trend in the ASIR of AF/AFL in the USA from 1990 to 2021, with a more pronounced increase among women. We further predicted that the USA will maintain a high ASIR throughout the period from 2022 to 2050. The USA is experiencing population aging, with the proportion of the population aged 65 and over rising from 12.5% in 1990 to 16.8% in 2020, and projected to reach 20.9% by 2050.^[14] The incidence of AF/AFL increases significantly after the age of 65 years.^[15] According to the most recent statistics, the life expectancy for women in the USA is 82.3 years, compared to 77.4 years for men.^[16] This indicates that women are exposed to the risk of developing AF/AFL for longer periods than men due to their greater longevity. Hypertension, diabetes mellitus (DM), and obesity have been identified as significant risk factors for the onset and persistence of AF/AFL, with higher prevalence in the USA.^[17] Although the USA has implemented measures to control the prevalence of hypertension, DM, and obesity – including the National Diabetes Prevention Program and Healthy People 2020/2030 – challenges persist. For instance, the overall prevalence of hypertension has improved, but significant disparities exist in its control and recognition rates.^[18] The obesity prevalence across the population (especially severe obesity among adults) has not experienced a significant decrease; in fact, the obesity burden continues to persist. It is predicted that the prevalence of obesity will continue to increase through 2050.^[19] Additionally, medical interventions have improved survival rates among cardiovascular disease patients and increased the risk of developing AF/AFL. Advancements in diagnostic techniques and monitoring methods have enabled the timely detection of previously undiagnosed occult or transient AF/AFL. Therefore, the USA needs to continuously enhance management of common risk factors, as well as employ new approaches such as digital health tools, wearable devices, widespread standardized anticoagulation therapy, and the promotion of catheter ablation to prevent the burden of AF/AFL from worsening.

The ASIR of AF/AFL in Canada and Argentina (particularly during 1996–1999) showed a declining trend over the study period, with a more pronounced decrease observed among women than men. Canada is one of the countries with the heaviest burden of AF/AFL. As early as the 1990s, it implemented robust public health interventions targeting tobacco control, diet, and physical activity, such as the Tobacco Products Control Act of 1994 and the gradual implementation of comprehensive indoor smoking bans after 2001.^[20] Screening and widespread medication for hypertension and high cholesterol have significantly reduced cardiovascular complications. The Canadian Hypertension Education Program has increased hypertension diagnosis and control rates.^[21] These initiatives have improved cardiovascular risk factors. In addition, the widespread adoption of the family physician system and the overall improvement in public health awareness have further reduced the incidence of AF/AFL. Argentina experienced an economic crisis in the mid-1990s, which may have led to short-term improvements in cardiovascular burden through indirect effects on dietary patterns (reduced consumption of high-salt, high-fat foods). In the late 1990s, Argentina strengthened public health measures for cardiovascular diseases, such as promoting prevention and treatment for hypertension and coronary heart disease, and improving access to medications.^[22]

Before menopause, estrogen provides cardiovascular protection in women, often delaying the peak incidence of AF/AFL by approximately 5 to 10 years compared to men.^[11] During the 1990s to 2020s, many women entered the high-risk age range for AF/AFL, enabling improved prevention and control measures to precisely target this critical population. In Canada and Argentina, public health campaigns, such as tobacco control initiatives and prenatal smoking cessation education, have been more targeted toward women, resulting in more significant behavioral changes among their populations. Since the 1990s, women’s smoking rates have declined more rapidly (particularly in Canada, where the decline has been most pronounced).^[23] Furthermore, previous studies have found that women often demonstrate higher medication adherence than men for chronic conditions such as hypertension and diabetes, and long-term medication use leads to a more significant reduction in AF/AFL risk. We also predicted a slight increase in AF/AFL incidence in Canada and Argentina between 2022 and 2050. This may be attributed to accelerated population aging, an expanding base of elderly women and individuals with multiple comorbidities; rising obesity and diabetes rates in certain populations; and men in high-risk groups not benefiting equally from previous prevention and control measures. Therefore, Canada and Argentina need to strengthen the prevention and control of AF/AFL among high-risk populations based on their national situations.

It is noteworthy that Italy experienced a significant increase in AF/AFL incidence from 2019 to 2021, and then stabilized until 2050. Previous studies have found that SARS-CoV-2 infection was associated with an increased risk of new-onset AF/AFL (adjusted-odds ratio, 4.24).^[24] Due to strained healthcare resources during the COVID-19 pandemic, the management of chronic conditions such as hypertension, diabetes, and obesity has been impacted, leading to an increase in the high-risk population for AF/AFL. Research indicates that Italy experienced a significant short-term increase in hospital admissions for AF/AFL during the peak of the COVID-19 pandemic.^[25] Moreover, changes in healthcare systems and reporting mechanisms during the pandemic have increased the diagnosis and reporting rates of AF/AFL. For instance, more rigorous inpatient and emergency department documentation systems, along with more comprehensive data collection, have led to widespread ECG monitoring upon patient admission, making it easier to detect previously undiagnosed, hidden AF/AFL. The increase in AF/AFL incidence in Italy may be due to short-term environmental and infectious disease impacts causing fluctuations in incidence rates. Future studies should explore the long-term outcomes of patients with new-onset AF/AFL after SARS-CoV-2 infection.

The incidence of AF/AFL is higher in high-income countries, which is consistent with findings from previous studies.^[3] This study further reveals that over the past 3 decades, the incidence of AF/AFL has risen more significantly in developing countries. For instance, in China, a marked increase in incidence has been observed across all age groups. A possible reason is that advances in diagnostic technology in developing countries have enabled the identification of early-stage and asymptomatic cases of AF/AFL.^[26] Aging is the most significant risk factor for AF/AFL. Population aging has become a major social issue in developed countries, while in developing countries, the number of older adults is surging due to their large population bases, placing greater strain on healthcare systems. Moreover, the rising prevalence of high-risk factors for AF – such as elevated systolic blood pressure, obesity, smoking, and DM – in developing countries further exacerbates the AF/AFL burden.^[27] The latest American Heart Association guideline has incorporated weight loss strategies, smoking cessation programs, alcohol reduction recommendations, and hypertension treatment plans to address current challenges.^[28] Therefore, countries – particularly those with a growing burden of AF/AFL – urgently need to develop comprehensive strategies that shift resource allocation toward effective monitoring of modifiable risk factors, with the aim of more effectively preventing and managing AF/AFL.

Although the incidence of AF/AFL is higher in older adults, the upward trend is more pronounced among younger individuals in most countries, especially in Germany and China. Previous studies have indicated a causal relationship between obesity and the onset of AF/AFL, suggesting that obesity may be a particularly important risk factor for AF/AFL in young adults, with the incidence among obese young adults being at least twice that of their normal-weight counterparts.^[29,30] Furthermore, evidence suggests that the development of AF/AFL in younger patients may be more strongly influenced by nontraditional risk factors, such as psychological characteristics (post-traumatic stress disorder, anger, and hostility) and behavioral/lifestyle factors (heavy alcohol consumption, smoking, and vigorous exercise or physical activity), whereas traditional cardiovascular risk factors may be less prevalent in this population.^[31] Therefore, further research is urgently needed to refine risk stratification, prevention, and treatment strategies across different age groups.

Our study has several limitations. First, although GBD has broad inclusion criteria for different types of data sources, data are not available for certain locations, and estimates are based on either predictive covariates or trends from neighboring locations. This may have introduced bias into our study, especially in economically developing countries. Second, there is a time lag from the date of data collection to its inclusion in the databases, which may cause a time lag in the evaluation of AF/AFL. Third, there are different types of AF/AFL, including paroxysmal, persistent, and permanent AF/AFL, but the GBD database does not recognize this complexity and only identifies whether a population falls within the AF/AFL classification. Further studies are warranted to include the different types of AF/AFL. Fourth, because individual-level information on major cardiovascular risk factors and comorbidities was not consistently available in the GBD AF/AFL datasets, we were unable to account for these factors, and the observed incidence trends reflect population-level patterns rather than risk-factor-specific effects.

5. Conclusions

In conclusion, based on an analysis of GBD 2021 data from a global perspective, the ASIR of AF/AFL is projected to remain stable or increase in most countries by 2050. AF/AFL continues to pose a major global public health challenge. A substantial number of AF/AFL cases is expected to persist, underscoring the need for dietary and lifestyle interventions alongside comprehensive screening and management strategies targeting high-risk populations, particularly in countries where the incidence of AF/AFL is projected to increase.

Acknowledgments

The authors would like to thank all members of the Institute for Health Metrics and Evaluation (IHME) and all collaborators involved in GBD 2021 study.

Author contributions

Formal analysis: Minjie Yuan, Miao Ye.

Methodology: Minjie Yuan, Yana Zhao.

Supervision: Tan Lyu.

Validation: Miao Ye.

Visualization: Minjie Yuan, Miao Ye, Chen Li.

Writing – original draft: Minjie Yuan, Chen Li.

Writing – review & editing: Haina Chen, Tan Lyu.