Athletes And Strokes: A Troubling Trend

While stroke is a rare clinical entity in sports, athletes are not immune to it. Stroke, or cerebrovascular accident, affects one in 10,000 people between the ages of 14 and 45, and hospital admissions for this condition are currently rising in the 20-59 age group. The risk of neurovascular injury may depend on the type of sport, and while sport-specific incidence rates are unknown, certain sports with a higher risk of impact, collision, or microtrauma can lead to stroke. For example, American football is the most prevalent sport associated with stroke. Other factors that can increase the risk of stroke in athletes include lifestyle choices, such as the use of performance-enhancing drugs, dehydration, and underlying genetic conditions. Recognising the signs of a stroke and seeking immediate medical attention are crucial for optimal recovery.

Headaches, head trauma, and neck injuries are common precursors to strokes in athletes

Headaches, Head Trauma, and Neck Injuries: Common Precursors to Strokes in Athletes

Headaches

Headaches are a common post-injury symptom in athletes and can be a precursor to strokes. Post-traumatic headaches (PTHAs) can vary in presentation and severity, ranging from migraine to tension-type headaches. The pathogenesis of PTHAs is not fully understood, but it is believed to involve a combination of factors such as the mechanism of injury, biological and behavioral responses, and individual risk factors.

Head Trauma

Head trauma, including concussions, is a significant risk factor for strokes in athletes. Repeated or severe head trauma can lead to traumatic brain injury (TBI), which can cause widespread vascular damage and axonal dysfunction. TBI can also trigger an inflammatory response in the brain, leading to the release of pro-inflammatory substances that can contribute to secondary injuries and neurological symptoms.

Neck Injuries

Neck injuries, particularly those involving hyperextension or hyper-rotation, can lead to vertebral artery dissection, which is a common cause of stroke in young athletes. Cervical carotid dissection associated with contact sports or high-impact activities has been reported in several cases.

The presence of these precursors underscores the importance of recognizing and managing them appropriately to reduce the risk of stroke in athletes. Early identification, accurate diagnosis, and prompt treatment are crucial to prevent long-term neurological deficits and potential disability.

Athletes in high-impact sports like American football are at a higher risk of stroke

Stroke is a rare clinical entity in sports, but athletes are not immune to it. Sports with an aspect of impact, collision, or microtrauma can lead to subsequent stroke, and athletes in high-impact sports like American football are at a higher risk.

Risk factors

The risk of injury to the neurovascular structures depends on the type of sport involved. Cervicocerebral artery dissection is often identified as the main cause in young athletes. Other risk factors include lifestyle or modifiable risk factors, genetic predispositions or non-modifiable risk factors, and trauma prevention factors such as sport or stroke triggers.

Lifestyle risk factors include the use of performance-enhancing drugs, recreational drug and alcohol consumption, cigarette smoking, and supplements and dietary choices. Genetic predispositions can put individuals at a much greater risk for stroke, and screening prior to play is a much-debated topic. Trauma prevention factors include the type of sport and stroke triggers.

Symptoms

The most common symptoms of stroke include headache, head trauma, and neck injury and/or vertebral artery dissection. Other notable inciting events include genetic predisposing conditions, thrombo-embolic clots, and hydration suspected complications.

Prevention and treatment

Prevention for stroke broadly encompasses three areas: lifestyle or modifiable risk factors, genetic predispositions or non-modifiable risk factors, and trauma prevention factors.

Treatment for stroke often involves a combination of medication and physical therapy to regain mobility and strength. In some cases, surgery may be required to repair damage caused by the stroke.

Lifestyle choices like drug use, diet, and hydration status can increase the likelihood of a stroke

Lifestyle choices such as drug use, diet, and hydration status can increase the likelihood of a stroke. Drug use, particularly the use of performance-enhancing drugs, has been linked to an increased risk of stroke in athletes. Anabolic steroids, for example, have been associated with artery damage and stroke in athletes under 30. Supplements containing ephedrine have also been linked to adverse cardiovascular effects such as vasoconstriction, vasospasm, and hypertension-induced subarachnoid hemorrhage.

Dietary choices can also impact stroke risk. A diet high in salt and fat, for instance, can increase the likelihood of a stroke. Additionally, dehydration has been identified as a risk factor for stroke, especially in endurance athletes. Dehydration can lead to altered packed cell volume and electrolyte balance disturbances, which are associated with comorbidities of stroke.

It is important to note that stroke risk is influenced by a combination of lifestyle choices and genetic factors. While lifestyle choices can increase the likelihood of a stroke, other factors such as family history and underlying health conditions also play a role.

Genetic predispositions, such as atrial septal defects, can also be contributing factors

Genetic Predispositions and Stroke Risk in Athletes

Genetic predispositions can increase an athlete's risk of experiencing a stroke. While the exact incidence of cardioembolic strokes in athletes with atrial septal defects (ASDs) is unknown, this condition is a contributing factor. ASDs are congenital heart defects that can cause blood to flow between the heart's upper chambers, creating a right-to-left shunt. This mechanism can lead to cardioembolic strokes, which occur when a venous thrombus travels through the ASD and causes a blockage in the brain.

Athletes with ASDs may experience cryptogenic strokes, which are those with unknown causes. In such cases, cardiac ultrasound can be used to check for the presence of an ASD. Additionally, atrial fibrillation, a common complication in individuals with ASDs, can also increase the risk of cardioembolic strokes.

ASDs and patent foramen ovale (PFO) are associated with an increased risk of perioperative acute ischemic stroke in athletes undergoing non-cardiac surgery. This risk is observed across all major surgical subtypes. However, ASDs and PFOs were not found to be associated with an increased risk of myocardial infarction or in-hospital death.

Other Genetic Risk Factors

In addition to ASDs, other genetic risk factors have been implicated in the literature. However, the evidence is not yet conclusive, and further research is needed to identify specific risk alleles. Here is a summary of some of the potential genetic risk factors:

• Inflammation-related genes: Studies have found associations between specific polymorphisms in the IL6 and TNF-α gene promoters and hemorrhagic stroke. However, the results have been inconsistent and require further replication.
• Renin-angiotensin-aldosterone system: The angiotensin-converting enzyme (ACE) gene has an insertion/deletion polymorphism that has been linked to hemorrhagic stroke in some populations but not in others.
• Blood coagulation: Polymorphisms in genes related to blood coagulation, such as Factor XIII and Factor VII, have been investigated, but the results have been conflicting.
• Lipid metabolism: Apolipoprotein E (ApoE) alleles have been associated with hemorrhagic stroke risk in some studies, but meta-analyses have yielded mixed results.
• Homocysteine metabolism: Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene have been linked to both hemorrhagic and ischemic stroke, but the findings are inconsistent.

Stroke symptoms in athletes are often misdiagnosed or confused with other conditions

Additionally, medical professionals may be hesitant to use the term "stroke" when diagnosing and documenting stroke in athletes, instead using technical terminology such as "vertebral artery dissection" or "cerebral embolization". This can contribute to the misdiagnosis or confusion of stroke symptoms in athletes.

To improve the accuracy of stroke diagnosis in athletes, it is important for healthcare providers to be aware of the possibility of stroke when evaluating athletes with neurological deficits or even just headaches. A complete medical history, including a review of symptoms, risk factors, and trauma history, can also help improve the accuracy of stroke diagnosis in athletes.

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