What is SECRETO study?

SECRETO is an international multicenter study aiming to evaluate accurately risk factors, mechanisms, and prognosis of cryptogenic ischemic stroke (i.e. brain infarctions of unknown cause) in young adults aged under 50 years. The study is currently recruiting participants in several European countries.

You may have been asked to participate SECRETO study, if you have been recently diagnosed with a cryptogenic brain infarction despite thorough diagnostic work-up.

Healthy controls

You may also have been asked to participate the study as a healthy control person without a previous stroke, since SECRETO is a case-control study. For each patient, we will search a healthy control person of similar age and same sex as the patient. Such study setting allows accurate comparison of risk factors between patients and healthy control persons and determine, which of the factors are connected to the disease and which are not.

What happens in the study?

Whether you are a patient or a healthy control, you will first meet a research physician who will explain further the study protocol and ask you to sign a written consent before any  study procedures can take place. Then you will be interviewed with a structured questionnaire, your weight, height, waist and hip circumference, as well as blood pressure will be measured. A blood sample will also be drawn (50 ml of venous blood).


Patients will be asked to revisit the study unit after 3 months and they will be interviewed and clinically examined again. Another blood sample will be taken then. Thereafter, patients will be contacted by telephone annually for 10 years, or depending on preferences and local practices, study visits can also be organized.

What is done with the blood samples?

With the blood samples, we aim to find new abnormalities in coagulation and e.g. markers of inflammation or dysfunction of the inner layer of arteries, as well as genetic abnormalities that may be involved in cryptogenic stroke. Before analyses, samples will be processed according to a standardized protocol, frozen, and stored anonymously.

What is SECRETO Family Study?

All participants in SECRETO will be interviewed with a structured form about family history concerning strokes and other cardiovascular diseases and events. Patients with several young-onset arterial or venous events in their close family will be asked to participate SECRETO Family Study, which is a substudy to the main study. The aim of this substudy is to find genetic factors playing role in strokes in young people and eventually disclose new  mechanisms for this disease.

Because stroke at young age is relatively rare event, a family study may be more efficient way to find relevant genetic factors associated with the disease compared with other genetic study methods. You may be asked to contact your relatives and after filling in an informed consent, they will be interviewed with a structured form and by telephone, and asked to donate a blood sample for genetic analysis. They do not have to visit the research unit.


SECRETO Oral is another substudy that aims to examine the association between oral and dental health and cryptogenic stroke. This is because earlier studies have found that particularly younger patients and those with cryptogenic stroke are frequently diagnosed a periodontitis, which is an inflammatory condition affecting the tissue surrounding and supporting the teet.

An x-ray (orthopantomography) of your teeth will be taken and an experienced study dentist will do an extensive dental examination and collects gingival and saliva samples for microbiological analysis. In patients, dental examination can take place several weeks after the stroke. SECRETO Oral recruits both patients and healthy controls and is currently performed at selected study sites in Finland.

SECRETO Extensive Cardiovascular Study

In this substudy, both patients and controls will be examined with non-invasive ultrasound-based methods to measure arterial stiffness and thickness of the inner layer of common carotid artery. Furthermore, function of the inner layer of arteries (endothel) will be measured with Endo-PAT device. This substudy is currently conducted in Helsinki only.

General information

Taking part in the study is completely voluntary. All data collected will be coded and anonymized, and registered in the study database without any personal identification.

Patients participating in SECRETO study are diagnosed and treated according to best available evidence and current practice. Study itself does not involve making treatment decisions – these are solely the responsibility of your treating physician. No new drugs or diagnostic methods are tested in the study.


Thank you for your interest in SECRETO study! 

Please contact your local investigator to hear more.