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This editorial refers to ‘Risk of arrhythmias in 52 755 long-distance cross-country skiers: a cohort study’[†][1], by K. Andersen et al. , on page 3624 Exercise is one of the most powerful lifestyle intervention strategies for the primary and secondary prevention of cardiovascular disease. There is a wealth of evidence regarding the lower ranges of the exercise dose–response relationship providing concrete evidence for the current recommendations of at least 30 min of moderate intensity exercise on most days as a means of reducing cardiovascular events.1 However, there is an increasing proportion of today's society engaging in sports practices which vastly exceed these guidelines, and there has been very limited study of the upper ranges of the exercise dose–response relationship.2 On the one hand are studies suggesting that long-term health and life expectancy of well-trained athletes is superior to that of the general population,3−5 while, on the other, there is evidence suggesting an increased prevalence of arrhythmias and chronic structural remodelling of the athletic heart.6−9 Atrial fibrillation (AF) may therefore represent the most intriguing and best evidenced example of the interplay between exercise and cardiac health. AF can be diagnosed in ∼1% of the population by age 60 and in >10% when older than 80 years,10 making it the most prevalent sustained arrhythmia in adults. In cohorts of young or middle-aged subjects, AF is relatively uncommon, thus implying that large cohorts would be required to provide sufficient power to identify any excess in prevalence due to sports practice. In this context, it is not surprising that Pelliccia et al . found only very few cases of AF despite significant left atrial enlargement in a fairly large ( n = 1777) athletic cohort aged 24 ± 6 years.11 In contrast, Baldesberger et al . … [1]: #fn-2
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EDITORIAL
Atrial fibrillat ion in athletes and the interplay
betw een exer cise and health
Andre La Gerche
1,2
and Christian Marc Schmied
3
*
1
St Vincent’s Hospital Department of Medicine, University of Melbourne, Fitzroy, Australia;
2
Department of Cardiovascular Medicine, University of Leuven, Leuven, Belgium;
and
3
Cardiovascular Center, Division of Cardiology, University Hospital Zurich, Ra¨mistrasse 100, CH-8091 Zurich, Switzerland
This editorial refersto ‘Riskof arrhythmias in52 755 long-dis-
tance cross-country skiers: a cohort study’, by K. Andersen
et al., doi:10.1093/eurheartj/eht188
Exercise is one of the most powerful lifestyle intervention strategies
for the primary and secondary prevention of cardiovascular disease.
There is a wealth of evidence regarding the lower ranges of the exer-
cise doseresponse relationshipproviding concrete evidence forthe
current recommendations of atleast 30min of moderate intensityex-
ercise on most days as a means of reducing cardiovascular events.
1
However, there is an increasing proportion of today’s society en-
gaging in sports practices which vastly exceed these guidelines, and
there has been very limited study of the upper ranges of the exercise
doseresponse relationship.
2
On the one hand arestudies suggesting
that long-term health and life expectancy of well-trained athletes is
superior to that of the general population,
325
while, on the other,
there is evidence suggesting an increased prevalence of arrhythmias
and chronic structural remodelling of the athletic heart.
629
Atrial fibrillation (AF) may therefore represent the most intriguing
and best evidenced example of the interplay between exercise and
cardiac health. AF can be diagnosed in 1% of the population by age
60 and in . 10% whenolder than80 years,
10
makingit themost preva-
lent sustained arrhythmia in adults. In cohorts of young or middle-aged
subjects, AF is relatively uncommon, thus implying that large cohorts
would be required to provide sufficient power to identify any excess
in prevalence due to sports practice. In this context, it is not surprising
thatPellicciaet al.foundonlyvery fewcasesof AFdespitesignificantleft
atrial enlargement in a fairly large (n ¼ 1777) athletic cohort aged
24 + 6years.
11
In contrast, Baldesberger et al.wereabletoidentify
an excess of AF when comparing a small cohort of 62 former profes-
sional cyclists with 62 ex-golfers aged 66 + 7years.
6
Although one
must always consider type 1 errors (false discoveries) in studies of
small sample size, it may also be that a true exercise-induced excess
in AF prevalence becomes appreciable when the cohort reaches an
age in which AF is more common and when the amount of exercise
practised is relatively extreme. In this context, the recent study of
Andersen et al. is remarkable.
12
The group of participants in the
popular Vasaloppet 90 km cross-country ski race was young and
healthy when one considers the likelihood of identifying incident AF.
Lessthan 10% ofthe cohort wasaged .60 years and those with signifi-
cant co-morbidities were few, as evidenced by the exclusion of parti-
cipants with known cardiovascular disease and by the fact that the
cohort had better health behaviour and overall longevity than the
average Swedish population.
13
Many of the established risk factors
for AF, such as hypertension, heart failure, diabetes, and obesity,
14
are likely to be under-represented within this group of cross-country
ski enthusiasts and, thus, we might expect such a low prevalence of AF
that detecting any residual risk attributable to exercise dose would be
difficult. However,the very large cohortsize of 52 755 athletes andthe
creative measures of exercise enabled the authors to define a ‘dose
response curve that provides further circumstantial evidence for the
premise that AF risk is increased in the very fittest athletes and in
those who perform exercise over many years. Andersen et al. investi-
gated the primary endpoint of any arrhythmia, which was a composite
of brady-and tachyarrhythmias, and determined that those completing
the race within 60% of the winner’s time were 1.3 times more likely to
be diagnosedwith anarrhythmiathanthosewhotookmorethan twice
the time to complete the race. Similarly, those who had completed the
race 5 times had a 1.3-fold increase in arrhythmic risk as compared
with those who completed the race only once. The primary endpoint
was predominantly driven by AF, with a similar trend seen in bradyar-
rhythmias (though fewer events, making definitive conclusions diffi-
cult). There was no apparent association between exercise measures
and supraventricular arrhythmias other than AF/atrial utter, and
therewere too few ventricular arrhythmic eventsto draw conclusions.
One of the biggest limitations when trying to interpret the data of
Andersen et al. istrying to workout a reference point againstwhich to
interpret the described prevalence of arrhythmias. The lowest preva-
lence of arrhythmias was observed in the slowest athletes who had
raced least; but what is the critical ‘cut-off’ concerning the amount
of exercise that leads to an elevated risk for developing AF? We
are frequently asked: ‘How many hours of exercise and at what inten-
sity before I am at risk of AF?’, but there are numerous complexities
which make it difficult to give prescriptive guidelines. First, as sum-
marized in Figure 1, arrhythmias such as AF are the clinical expression
of an interplay between host, environmental, and disease-specific
* Corresponding author. Tel: +41-76 344 8308, Fax: +41-442558701, Email: christian.schmied@gmx.ch or christian.schmied@usz.ch
The opinions expressed in this article are not necessarily those of the Editors of the European Heart Journal or of the European Society of Cardiology.
Published on behalf of the European Society of Cardiology. All rights reserved.
& The Author 2013. For permissions please email: journals.permissions@oup.com
European Heart Journal
doi:10.1093/eurheartj/eht265
European Heart Journal Advance Access published July 24, 2013
at University of Melbourne on July 24, 2013http://eurheartj.oxfordjournals.org/Downloaded from
factors. Host factors include age, gender, other genetic factors (from
single-gene mutations to multiple nucleotide polymorphisms),
obesity, alcohol consumption, sleep apnoea, and others.
15
Disease-
related factors includeatrial stretch,autonomic balance, and systemic
and local inflammation, while environmental factors include dietary
factors, concurrent illnesses, and exercise.
15
It is extremely difficult
to define the magnitude of the risk attributable to exercise in isola-
tion. In particular, the influence of gender is an important case in
point. A massive limitation of all exercise studies, including that of
Andersen et al., is the lack of data pertaining to females. There is cur-
rently no evidence that sports’ training constitutes a risk for AF in
females, but this is largely due to the gross under-representation of
females in sports cardiology research.
Thesecondissuein tryingtodefineclinical recommendationson the
perfect amount of exercise to minimize the risk of arrhythmias relates
to the difficulties in comparing measures of exercise dose across
studies.Variousquestionnaireshave beendeveloped to assessthe dur-
ation, frequency, and intensity ofphysical activity, but they remain fairly
coarse estimates for defining exercise exposure subject to consider-
able bias.
16
For example, the subjective assessment of exercise inten-
sity is inversely associated with a person’s fitness, such that jogging, for
example,willbe rated as 3/10 intensityby someoneof excellentfitness,
butas 7/10bysomeonewithpoor fitness.
17
Asimilareffectcanbeseen
when comparing literature across various disciplines; what is seen as
vigorous exertion in cardiovascular epidemiology studies would not
even be considered warm up tempo in sports science parlance.
18
The term ‘high intensity exercise can be used to describe walking up
a flight of stairs in some studies of AF
18
or, in the case of the study
of Andersen et al.,
12
can be applied to 90 km of cross-country ski
Figure 1 Interplay between environment, person, and disease
in the clinical expression of atrial fibrillation.
Figure 2 U-shaped relationship between the exercise dose and the relative risk of developing atrial fibrillation (AF). Composite data from three
separate trials along the x-axis demonstrating an association between reducing prevalence of AF with increasing exercise of low intensity but then an
increasing risk of AF with moderate and intense exercise. The echocardiogram examples above demonstrate the progressive cardiac remodelling
from a typical sedentary subject (left), a leasure-time athlete (middle), and a professional cyclist (right). The 10 cm marker on the echocardiogram is
highlighted with a red circle and the images have been scaled relative to this. The inference is that as exercise dose increases, the heart gets bigger and
the risk of AF increases. Whether or not there is a causal relationship between cardiac enlargement and arrhythmias is still to be determined.
EditorialPage 2 of 4
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racing. With this in mind, we have tried to construct a ‘guestimate of
relativeexercisedosesinthreelandmarkstudiesinvestigatingthe inter-
action between exercise and AF incidence. Our best attempt at trying
to integrate data across very disparate studies is presented in Figure 2.
The risk of AF decreases as one engages in regular physical activity of
mild to moderate exertion, as evidenced by the study of elderly sub-
jects by Mozaffarian et al.
19
However, as reported by Aizer et al.,
when thelevel ofexertionis equivalent to jogging, thena greater preva-
lence ofAF is appreciable in those jogging dailyas compared with those
jogging 12 times/week.
20
A reasonable ‘guestimate’ when consider-
ing the level of physical conditioning required to compete in the Vasa-
loppet ski race would suggest that Andersen et al. complete the
sporting spectrum by describing people mostly of moderate to ex-
tremely high physical conditioning. Thus, some picture of the exercise
doseresponse curve emerges, with a U-shaped pattern suggesting
thatregularmildto moderateexercisemayprovidea degreeof protec-
tion from AF while more sustained vigorous exertion represents a risk
factor. This is supported by a number of casecontrol studies which
have demonstrated a consistent association between endurance exer-
cise and AF/atrial flutter.
6,21227
With considerable caveats noted,
these studies provide us with some idea to guide our answer regarding
the dose of exercise required to promote AF. Perhaps they also
provide a clinical clue that we should be advising our athletes with
AF to reduce their training intensity and volumes, but certainly not
to cease exercise practice all together. The wisdom of such advice
will really only be known after well-designed studies specifically
address the efficacy of such interventions.
Whilst the studyof Andersen et al. helps to expand our understand-
ing of the epidemiology of exercise-induced arrhythmias, it does not
provide any insights into underlying mechanisms. However, recent
studies in animals and humans support the premise that exercise
may serve as a trigger, a modulator, and contribute to the underlying
substrate for the promotion of arrhythmias. A collaboration
between the Barcelona group of Lluis Mont and the Montreal group
of Stanley Nattel has demonstrated that a model of endurance training
in rats (the ‘marathon rat’) can be used to demonstrate increased in-
flammation and fibrosis, and enhanced vagal responsiveness affecting
the atria and right ventricle (curiously sparing the left ventricle)
whichpredisposestheanimalsto both AFandrightventriculararrhyth-
mias.
28,29
This resembles some of the observations in human athletes.
Heidbuchel and La Gerche observed that endurance exercise can
promote remodelling and arrhythmias which seems to favour the
right ventricle disproportionately,
8,9
whereas Luthi et al.,
30
amongst
others, have demonstrated biatrial remodelling. The other intrigue
to which these studies are drawn is whether the remodelling asso-
ciated with exercisetraining (theso-called‘athlete’sheart’) is anentire-
ly physiological process. As detailed in Figure 2, increasing exercise
training is associated with cardiac remodelling which can be profound.
It remains to be determined whether those athletes with the biggest
hearts are at greatest risk of arrhythmias.
Conflict of interest: none declared.
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... This effect seems to be gender-specific and more pronounced in younger males. Regular exercise of either low or moderate intensity seems serve as a preventive strategy for cardiovascular disease and AF, while higher-intensity endurance exercise may lead to [12][13][14][15][16][17][18][19][20][21]. Moreover, although the prevalence of AF increases with age, the relative risk for athletes compared to nonathletes seems to be higher in younger athletes [22,23]. ...
... Many retrospective observational studies and meta-analyses have estimated a 2 to 10 times higher frequency of AF in high-intensity endurance athletes compared to individuals who do not exercise [6][7][8][12][13][14][15][16][17]. A U-shaped relationship between male elite athletes and AF is demonstrated through this finding, suggesting that both the type (endurance) and the dose (hours of training) of physical activity seem to relate to AF development [14,[18][19][20][21]. This U-shaped relationship has not been confirmed in women [14]. ...
... This effect seems to be gender-specific and more pronounced in younger males. Regular exercise of either low or moderate intensity seems serve as a preventive strategy for cardiovascular disease and AF, while higher-intensity endurance exercise may lead to AF [6-8, [12][13][14][15][16][17][18][19][20][21]. Moreover, although the prevalence of AF increases with age, the relative risk for athletes compared to nonathletes seems to be higher in younger athletes [22,23]. ...
Article
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Although the benefits of exercise training have been shown repeatedly in many studies, its relationship with the occurrence of atrial fibrillation (AF) in competitive athletes still remains controversial. In the present review, we sought to demonstrate a comprehensive report of the incidence, pathophysiology, and therapeutic approaches to AF in elite athletes. A 2 to 10 times higher frequency of AF has been shown in many studies in high-intensity endurance athletes compared to individuals who do not exercise. Moreover, a U-shaped relationship between male elite athletes and AF is demonstrated through this finding, while the type and the years of physical activity seem to relate to AF development. A strong correlation seems to exist among the type of exercise (endurance sports), age (>55 years), gender (males), and the time of exercise training, all contributing to an increased risk of AF. The pathophysiology of AF still remains unclear; however, several theories suggest that complex mechanisms are involved, such as bi-atrial dilatation, pulmonary vein stretching, cardiac inflammation, fibrosis, and increased vagal tone. Elite athletes with AF require a comprehensive clinical evaluation and risk factor optimization, similar to the approach taken for nonathletes. Although anticoagulation and rate or rhythm control are cornerstones of AF management, there are still no specific guidelines for elite athletes.
... Many retrospective, observational studies and meta-analyses have estimated a 2 to 10 times higher frequency of AF in high intensity endurance athletes compared to individuals who do not exercise [6][7][8][12][13][14][15][16][17]. A U-shaped relationship between male elite athletes and AF is demonstrated through this finding, while the type (endurance) and the dose (hours of training) of physical activity seems to relate with AF development [14,[18][19][20][21]. This U-shaped relationship has not been confirmed in women [14]. ...
... This U-shaped relationship has not been confirmed in women [14]. Regular exercise of either low or moderate intensity seems to be a preventive strategy for cardiovascular disease and AF, but higher intensity of endurance exercise could lead to AF [6][7][8][12][13][14][15][16][17][18][19][20][21]. Moreover, although the prevalence of AF increases with age, the relative risk for athletes compared with nonathletes seems to be higher in younger athletes [22,23]. ...
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According to current knowledge, although the beneficial effects of regular exercise training are well recognized, there are conflicting data regarding its relation with the occurrence of atrial fibrillation (AF) in competitive athletes. The aim of this literature review was to demonstrate a comprehensive report of incidence, pathophysiology and management of AF in elite athletes. The frequency of AF to be 2 to 10 times greater in high intensity endurance athletes compared to sedentary individuals. A U-shaped relationship between male elite athletes and AF has been observed, while the type and the dose of physical activity seems to play a major role in AF development. Male gender, increasing age, endurance sports, and time of training are associated with AF, thereby confirming a likely association between athleticism and AF. Pathophysiology of AF still remains unclear but, there are suggested theories that include complex mechanisms such as alterations of autonomic tone, left atrial enlargement and fibrosis, electrical remodeling, and increased inflammation. Elite athletes with AF require a comprehensive clinical evaluation and risk factor optimization, similar to that for nonathletes. Although anticoagulation and rate or rhythm control are corner stones for AF management, however, there are still no specific guidelines for elite athletes.
... Nevertheless, some studies have associated intense physical activity with an increased risk of AF [18,19], reporting a higher incidence of AF in elite athletes [20][21][22] and suggesting a U-shaped dose-response curve [23,24]. These findings have raised doubts about the real beneficial effects of sports practice in arrhythmia prevention. ...
... Some papers [23,24] report that the relationship between AF and sport may be a "U-shaped" relationship whereby both a sedentary lifestyle and strenuous, long-duration PA may prove to be risk factors for AF. A lower risk of AF has been reported in patients practicing sport of moderate intensity or duration, but not during vigorous exercise [16]. ...
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Atrial fibrillation (AF) is the most common sustained arrhythmia in clinical practice, and it is an enormous burden worldwide because of its high morbidity, disability and mortality. It is generally acknowledged that physical activity (PA) is strongly associated with a significant reduction in the risk of cardiovascular (CV) disease and all-cause mortality. Moreover, it has been observed that moderate and regular physical activity has the potential to reduce the risk of AF, in addition to improving overall well-being. Nevertheless, some studies have associated intense physical activity with an increased risk of AF. This paper aims to review the main related literature to investigate the association between PA and AF incidence and draw pathophysiological and epidemiological conclusions.
... When it comes to tachyarrhythmia, weight reduction has been shown to be effective in preventing atrial fibrillation recurrences and alleviating symptoms in obese patients 29 . Nevertheless, PA might increase atrial fibrillation risk when individuals engage in frequent exercise and with high intensity, especially for vigorous exercise in younger adulthood and elite athletes 30 . Body fat distribution is an important risk factor for obesity-related diseases. ...
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Physical activity (PA) and obesity may alter the risks of cardiac conduction disease. Participants from the Kailuan cohort, who were free of cardiac conduction disease and with repeated measurements of electrocardiogram from 2006 to 2019, were included. The primary outcome was cardiac conduction disease. The secondary outcomes were atrioventricular block and intraventricular block. Cox regression was used to assess the association between obesity, PA, and the risks of the outcomes. Influences of PA on the associations between BMI and incident outcomes were evaluated. A total of 84,022 participants (mean age 50.15 years, SD 11.69; 80.3% male) were included. Over a median follow-up of 11.83 years (IQR 8.87–13.04), 3236 participants developed the primary outcome. After multivariable adjustment, a higher body mass index (BMI) and a higher waist circumference (WC) were associated with increased risks of conduction disease, but more PA was associated with a lower risk. For obese patients defined by BMI with low PA, the risk of conduction disease was higher than that of obese patients with high PA (HR: 1.42, CI: 1.21-1.66 vs. HR: 1.16, CI: 1.03–1.31). For central obese patients defined by WC with low PA, the risk of conduction disease was also higher compared to central obese patients with high PA (HR: 1.31, CI: 1.17–1.48 vs. HR: 1.12, CI: 1.03–1.23). Besides, compared to obesity with high PA, obesity with low PA was associated with a higher risk of atrioventricular block (HR: 1.70, CI: 1.28-2.27 vs. HR: 1.45, CI: 1.16-1.81) and intraventricular block (HR: 1.37, CI: 1.13-1.65 vs. HR: 1.03, CI: 0.92–1.15). Higher PA can reduce the risks of developing cardiac conduction disease, both in the obese and non-obese groups. ( Clinical Trial Registration URL: https://www.chictr.org . Unique identifier: ChiCTRTNC-11001489).
... Studies have observed that the prevalence of AF in athletes is 2-10 times greater than that in the general population (Sharma, 2018). This finding suggests a U-shaped relationship between sports and AF (Aizer et al., 2009;Andersen et al., 2013;La Gerche and Schmied, 2013;Morseth et al., 2016;Sciarra et al., 2022;Petrungaro et al., 2023), whereby AF seems to increase due to either deficient or excessive sports practice, and patients instead benefit from moderate exercise. The assumed mechanisms underlying this observation include fibrosis or inflammation, hemodynamic variations leading to left atrial enlargement, vagal tone, and genetic factors triggered by physical exercise (Flannery et al., 2017). ...
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Atrial fibrillation (AF) is a common cardiac arrhythmia that poses a significant risk of stroke and thromboembolic events. Anticoagulation therapy is essential for preventing stroke in patients with AF. An increasing number of people of all ages, including cardiac patients, approach physical activity as both a leisure-time exercise and a competitive sport. Therefore, patients at risk of AF are increasingly allowed to practice sports activities. Management of oral anticoagulant therapy (OAT) in these patients is extremely challenging because of the need to balance the risks and benefits of medications, considering both hemorrhagic (in case of trauma) and ischemic complications when the drugs are avoided. Official recommendations are limited for these patients and forbid sports that increase the risk of trauma and consequent bleeding in most cases. These recommendations are strongly influenced by the “traditional” management of OAT, which mainly involves coumarin derivatives. Non-vitamin K antagonist direct oral anticoagulants (DOACs), with their more favorable pharmacokinetic–pharmacodynamic profile than that of coumarin derivatives, may represent an opportunity to modify the approach to sports activity in patients with AF and indications for OAT. This study aimed to review the use of anticoagulants in athletes with AF, highlight their efficacy and safety, and provide practical considerations regarding their management.
... . Bei Sportler_innen führen strukturelle Anpassungen des Herzmuskels auf die vermehrte Druck-und Volumenbelastung zum klassischen Sportherz. Charakteristisch ist beispielsweise eine symmetrische Dilatation aller vier Herzhöhlen mit leichter linksventrikulärer Hypertrophie bei normaler Funktion [5]; darüber hinaus kommt es auch zu funktionellen und elektrophysiologischen Veränderungen [6]. Bei Sportlern sind im EKG unter anderem Sinusbradykardien und -arrhythmien, der AV-Block I ° und II ° vom Typ Wenckebach, gewisse Repolarisationsstörungen und Zeichen der linksventrikulären Hypertrophie als physiologisch zu werten [7]. ...
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Guidelines and Expert Consensus Documents summarize and evaluate all currently available evidence on a particular issue with the aim to assist physicians in selecting the best management strategies for a typical patient, suffering from a given condition, taking into account the impact on outcome, as well as the risk–benefit ratio of particular diagnostic or therapeutic means. Guidelines are not substitutes for textbooks. The legal implications of medical guidelines have been discussed previously. A great number of Guidelines and Expert Consensus Documents have been issued in recent years by the European Society of Cardiology (ESC) as well as by other societies and organizations. Because of the impact on clinical practice, quality criteria for development of guidelines have been established in order to make all decisions transparent to the user. The recommendations for formulating and issuing ESC Guidelines and Expert Consensus Documents can be found on the ESC web site (http://www.escardio.org/knowledge/guidelines/rules). In brief, experts in the field are selected and undertake a comprehensive review of the published evidence for management and/or prevention of a given condition. A critical evaluation of diagnostic and therapeutic procedures is performed, including assessment of the risk–benefit ratio. Estimates of expected health outcomes for larger societies are included, where data exist. The level of evidence and the strength of recommendation of particular treatment options are weighed and graded according to predefined scales, as outlined in the tables below. The experts of the writing panels have provided disclosure statements of all relationships they may have which might be perceived as real or potential sources of conflicts of interest. These disclosure forms are kept on file at the European Heart House, headquarters of the ESC. Any changes in conflict of interest that arise during the writing period must be notified to the ESC. The Task Force report was entirely …
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Context Atrial fibrillation is the most common arrhythmia in elderly persons and a potent risk factor for stroke. However, recent prevalence and projected future numbers of persons with atrial fibrillation are not well described.Objective To estimate prevalence of atrial fibrillation and US national projections of the numbers of persons with atrial fibrillation through the year 2050.Design, Setting, and Patients Cross-sectional study of adults aged 20 years or older who were enrolled in a large health maintenance organization in California and who had atrial fibrillation diagnosed between July 1, 1996, and December 31, 1997.Main Outcome Measures Prevalence of atrial fibrillation in the study population of 1.89 million; projected number of persons in the United States with atrial fibrillation between 1995-2050.Results A total of 17 974 adults with diagnosed atrial fibrillation were identified during the study period; 45% were aged 75 years or older. The prevalence of atrial fibrillation was 0.95% (95% confidence interval, 0.94%-0.96%). Atrial fibrillation was more common in men than in women (1.1% vs 0.8%; P<.001). Prevalence increased from 0.1% among adults younger than 55 years to 9.0% in persons aged 80 years or older. Among persons aged 50 years or older, prevalence of atrial fibrillation was higher in whites than in blacks (2.2% vs 1.5%; P<.001). We estimate approximately 2.3 million US adults currently have atrial fibrillation. We project that this will increase to more than 5.6 million (lower bound, 5.0; upper bound, 6.3) by the year 2050, with more than 50% of affected individuals aged 80 years or older.Conclusions Our study confirms that atrial fibrillation is common among older adults and provides a contemporary basis for estimates of prevalence in the United States. The number of patients with atrial fibrillation is likely to increase 2.5-fold during the next 50 years, reflecting the growing proportion of elderly individuals. Coordinated efforts are needed to face the increasing challenge of optimal stroke prevention and rhythm management in patients with atrial fibrillation.
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To determine whether Olympic medallists live longer than the general population. Retrospective cohort study, with passive follow-up and conditional survival analysis to account for unidentified loss to follow-up. 15 174 Olympic athletes from nine country groups (United States, Germany, Nordic countries, Russia, United Kingdom, France, Italy, Canada, and Australia and New Zealand) who won medals in the Olympic Games held in 1896-2010. Medallists were compared with matched cohorts in the general population (by country, age, sex, and year of birth). Relative conditional survival. More medallists than matched controls in the general population were alive 30 years after winning (relative conditional survival 1.08, 95% confidence interval 1.07 to 1.10). Medallists lived an average of 2.8 years longer than controls. Medallists in eight of the nine country groups had a significant survival advantage compared with controls. Gold, silver, and bronze medallists each enjoyed similar sized survival advantages. Medallists in endurance sports and mixed sports had a larger survival advantage over controls at 30 years (1.13, 1.09 to 1.17; 1.11, 1.09 to 1.13) than that of medallists in power sports (1.05, 1.01 to 1.08). Olympic medallists live longer than the general population, irrespective of country, medal, or sport. This study was not designed to explain this effect, but possible explanations include genetic factors, physical activity, healthy lifestyle, and the wealth and status that come with international sporting glory.