Why under 50-year-olds experience strokes – A study investigates the underlying reasons

Why under 50-year-olds experience strokes – A study investigates the underlying reasons

Every year, 1.3 million people worldwide suffer a stroke before turning 50 years old. The younger the patient, the more unclear the reasons for the stroke are. The underlying cause is not always identifiable despite extensive diagnostic work-up. Since the 1980s, The the number of young ischemic stroke patients has been rising. Today, in over one-third of the cases, the primary cause remains unknown. Jukka Putaala, Associate Prof., MD, Ph.D., from Helsinki University Hospital, wants to solve these cases.

In Finland, almost 600 people yearly suffer a stroke before turning 50, and the underlying cause is not always identifiable despite extensive diagnostic work-up. The younger the patient, the more likely it is that the reasons for the stroke remain unclear.

“In up to 50% of patients, the causes for ischemic strokes in adults younger than 50 years old remain unknown. These strokes are known as cryptogenic strokes. By researching this specific patient group, we hope to find valuable knowledge,” says the lead investigator Dr. Jukka Putaala. “By using and improving systematic research methods and imaging studies, we can find various acquired or inherited susceptibilities that might be a part of the causal mechanisms underlying these strokes.”

The symptoms are often sudden and difficult to detect

When comparing the clinical presentation in elderly people and the young, the symptoms are often very different. The symptoms in strokes in younger patients (under 50 years) might resemble, for example, an epileptic seizure or migraine attack. These might be more difficult to recognize as stroke than in the elderly. There is also more variety in differential diagnostic options. Usually, the symptoms of stroke are abrupt or can be present when waking up; however, in some cases, they develop gradually. The distribution of brain damage among young stroke patients also differs from that in the elderly. Younger patients may also experience basilar artery occlusions that may cause extremely severe symptoms.

The study aims to identify the underlying causes

The study aims to release the first results regarding the causes leading to such cryptogenic cerebral infarctions in younger patients in 2021. Study participants are currently being recruited from Finland and abroad, thanks to standardized research methods and processes established by Dr. Putaala and his colleagues.

Ideally, the results of the study can be utilized immediately by physicians treating these patients. Recognizing the factors that lead to a cryptogenic stroke can help to identify these in clinical practice; for example, they can be used to inform patients about avoiding certain risk factors. Among other things, the study seeks to identify previously unknown or poorly identified causative factors in blood coagulation. Some of the mechanisms of cryptogenic ischemic stroke in younger patients are partly known, but more information is needed. For example, a patent foramen ovale in the heart can allow the passage of a thrombus from the venous system into the arterial system and cause a stroke. However, it is still incompletely understood why a certain individual develops such a stroke. Blood coagulation abnormalities may play an important role in such strokes.

The aim is also to use genetic studies to find the underlying factors causing the stroke. The study essentially aims to create information for medical treatment and stroke prevention, but that can take years even in optimal circumstances. The disease etiology needs to be discovered before new experimental treatments can be attempted. These findings are crucial in making stroke prevention and patient care more efficient.

After a stroke, it is possible to return to work, but modern-day work is demanding on the brain.

A cerebral infarction is a serious and brain-altering event that leaves permanent damage. Luckily, the human brain is plastic, which means that it is capable of reorganizing itself. Other parts of the brain take over the role of the damaged part and, in many cases, the patient can recover enough to lead a normal life. Returning to work is seen in about 50% of patients, but if the work includes highly demanding cognitive tasks, a return to work is not always possible.

“A stroke changes the way the brain works, and even if the healing and recovery are very good based on physical indicators, performing certain cognitive, complex-thinking tasks can make one feel tired or more difficult,” Dr. Putaala says. In this case, a part-time work may be a successful solution.

Professionals from Finland and abroad participating in the research

The research is carried out in each of the University hospitals in Finland, involving the departments of neurology and cardiology, with collaboration with HUSLAB and FIMM. Currently, a total of 15 hospitals abroad are partners in the research as well, and they send anonymized patient data, data on brain scans and cardiac imaging, and blood samples to the research team. Standardized information collection ensures that certain steps in the research occur in a specific order and the data is collected in a specific way. The research is sponsored by the Academy of Finland, Hospital District of Helsinki and Uusimaa and other Hospital Districts in Finland. In addition, the research has received financial support from the Region West Götaland in Sweden and most recently from the National Neurocenter in Finland.

Significance of the study

Worldwide, approximately 1.3 million annual ischemic strokes occur prematurely in adults younger than 50 years of age. Despite modern-day diagnostic tools, up to half of these early-onset strokes remain cryptogenic, i.e., an identifiable cause for the stroke remains elusive. These patients are left in uncertainty since there are scarce data to guide disease prevention and treatment in these circumstances. Searching for Explanations for Cryptogenic Stroke in the Young: Revealing the Etiology, Triggers, and Outcome (SECRETO) is a prospective international multicenter case-control study of young adults aged 18-49 years presenting with an imaging-positive cryptogenic ischemic stroke after standardized work-up. The results are expected to improve diagnostic strategies, prevention, and knowledge of the prognosis of this understudied condition. The project also fuels the creation of personalized treatment schemes and the discovery of novel treatment targets.