In the Netherlands, some 50,000 experience a TIA every year. A TIA (Transient Ischemic Attack) is a temporary blocking of a blood vessel in the brain. This is caused by a constriction or blood clot and results in complaints such as a drooping mouth, slurred speech and loss of muscular power on one side of the body. Other symptoms include loss of feeling, partial blindness, vertigo and loss of balance. While complaints may differ significantly, it is typical of a TIA that they occur suddenly and at the same time. Unlike with a cerebral infarction, the symptoms of a TIA are very temporary and often only last a few minutes. "Anyone with these symptoms must contact a doctor as soon as possible, even if the symptoms are mild and disappear within a few minutes," says Faas Dolmans.

Medical emergency
He says a TIA should be considered a medical emergency. After a TIA, patients run the risk of having a cerebral infarction, which risk is greatest during the first days after a TIA. Prior research has shown that one in ten TIA patients suffers a cerebral infarction within 3 months. Faas: "Many people do not realize this. They really should contact a doctor as soon as possible to get medication that can prevent a cerebral infarction." This mainly concerns platelet inhibitors (blood thinners).

His PhD research shows that people wait too long seeking medical help for their complaints. Over a third of TIA patients waits over 24 hours. Even when the symptoms are recognized as being a TIA, this does not prompt them to get help more quickly. And people also seem to wait longer if the symptoms occur outside of office hours, despite the current 24-hour care in general practice centers. Faas: "The blatant underestimation of the gravity gives cause for a separate awareness campaign, in addition to the current cerebral infarction campaigns."

NHG TIA guideline
General Practitioners are insufficiently aware of the importance of starting medication quickly when they suspect a TIA. Faas: "For a long time, TIAs were considered a benign condition. In 2013, the NHG, the Dutch College of General Practitioners, included the recommendation in their "Stroke" guideline to immediately prescribe platelet inhibitors if a TIA is suspected and to urgently refer the patient to a neurologist in a specialized TIA clinic. Our study, which ran from 2013 to 2016, shows that while doctors' awareness has increased, about half of them do not comply with this guideline."

Faas gives two recommendations to improve this situation. Neurologists should recommend the immediate administration of platelet inhibitors when consulted by a GP. In addition, an update of the Dutch guideline for GPs should contain the hard and fast recommendation to always start platelet inhibitors immediately if there is a suspicion of a TIA, instead of the current more lukewarm recommendation to start.

Difficult diagnosis
Diagnosing a TIA can be difficult, both for GPs and for neurologists. Symptoms may be mild or vague, and several other conditions can trigger the same kind of symptoms, such as migraine and epilepsy. Doctors often have to rely solely on the patient's story, because the complaints have already disappeared. Moreover, in the vast majority of cases, a TIA cannot be demonstrated using imaging.

For this reason, Faas' PhD research also focused on biomarkers in the blood, which could help GPs make the diagnosis. Unfortunately, the biomarkers that are currently available have no practical added value. However, medical data are now available from primary care patients suspected by their GP of having a TIA. This includes people who were later given a diagnosis other than a TIA. Faas: "As such, our MIND-TIA cohort is a good reflection of reality. We took blood samples immediately after the suspicion and stored them. If and when new potential biomarkers become available, we can immediately test these for usability, without having to bother the patients again."

EDCT diagnosis tool
General practitioners could benefit from a diagnostic model, the Explicit Diagnostic Criteria for TIA (EDCT). Faas: "This is a set of clinical criteria drawn up by two Danish neurologists, which we have slightly modified. In our cohort, the EDCT proved particularly good at excluding a TIA: a negative result was justified in 97 percent of cases. It appears to be a suitable model for inclusion in the GP guideline in due course, but it must be tested in daily practice first. This is what we intend to do in a next step."

The PhD research ‘Optimizing diagnosis of Transient Ischemic Attack’ has been made financially possible by SBOH, the Dutch national association of physicians in employment.