A new online calculator, iStroke-BG, estimates a person's risk of ischaemic stroke over the next five years. It is built entirely on data from Bulgarians. The Brain Health Council Foundation presented it at a round table called "Artificial Intelligence and Stroke – From the First Minutes to a New Life", held ahead of World Stroke Day on 29 October. Psychiatrists and neurosurgeons took part together.

Users enter their health details and get a PDF form. They can print it and take it to their GP or a neurologist.

The calculator takes 12 risk factors into account: age, sex, blood pressure, treatment with drugs for high blood pressure, total cholesterol, diabetes, obesity and atrial fibrillation. Others include physical activity, smoking, regular alcohol use and a relative who has had a stroke.

Dr Mihail Petrov of the Pirogov emergency hospital in Sofia spoke about how the tool was developed. He said the aim is for the model to reflect features typical of Bulgarians, rather than follow only international research. Artificial intelligence helped pick the risk factors after a detailed review of the literature.

Building the model took four steps: selection, adaptation, testing and analysis. It rests on a retrospective study of 527 patients in three hospitals. The first clinical study included 227 stroke patients and 106 patients who had a mechanical thrombectomy, a procedure that removes the blockage mechanically. The coefficients were also checked on 100 people who happened to see an outpatient neurologist. Petrov said the calculator has shown that it works at every step so far.

Ischaemic stroke, he explained, is a sudden blockage of an artery in the brain that causes an abrupt loss of neurological function. The problem starts before the symptoms appear and before the ambulance arrives.

Bulgaria records 45,000 strokes a year, and the study found the number has not fallen significantly in three years in a row. Intravenous thrombolysis, in which a drug dissolves the clot through a vein, rose by 1.15% compared with 2023. Thrombectomies rose by 0.21%. "The results are good, but the share of people who get the treatment is under 1%, which is not really a good result," Petrov said.

Prof Nikolay Gabrovski, chairman of the foundation, said the country's stroke statistics have been alarming for years. The main problem, he said, is solved outside hospitals, at the stage of prevention.

Dr Nikolay Brunzalov, chairman of the Bulgarian Medical Union, told the round table that "the best-treated stroke is the one that never happens". He said Bulgaria has many good specialists and centres, but they are run with no link between them. A patient gets highly skilled treatment and is stabilised, but there is no long-term care afterwards, he said.

Dr Vanyo Vidkov, chairman of the board of the Sofia Medical Association, listed the costs of stroke: treatment, severe after-effects, disability, loss of ability to work and long rehabilitation. He believes the calculator can save lives through prevention.

The first level of the calculator is already live. Data will be collected as fast as possible and tracked for three to five years to see which coefficients need to be adjusted. For people with a "high risk" result, a second level is planned, with a more precise assessment, targeted action and risk reduction.