Stroke: High fatality rate and risk of recurrence

Team of researchers investigate progression of disease over a period of 20 years.

After a stroke, the chances of survival and the risk of recurrence in the following years vary greatly depending on what caused the stroke in the first place. This is the conclusion reached by researchers at FAU and University of Würzburg in a joint study. Their findings have recently been published in the journal Stroke (doi: 10.1161/STROKEAHA.120.029972).

In Germany, stroke is the third most common cause of death after cardiac disease and cancer, and the most common cause of lasting disability in adults. Approximately 200,000 men and women suffer their first stroke each year, and approximately 66,000 suffer a second or subsequent stroke. The most common form is an ischemic stroke triggered by a lack of circulation to the brain, often caused by a blood clot.

A team of researchers led by Prof. Dr. Peter Kolominsky-Rabas from FAU, and Viktoria Rücker and Prof. Dr. Peter U. Heuschmann from the University of Würzburg have now gained new insights into fatality and rate of recurrence after an ischemic stroke. The head of the Interdisciplinary Centre for Health Technology Assessment and Public Health, Prof. Kolominsky-Rabas, launched the Erlangen Stroke Register (ESPRO) in 1994 already. The extensive data it contains was used as the basis for the current study, allowing researchers to track the progression of cases over a period of twenty years. ‘Using the data saved in ESPRO, we are able to track all stages in parent care, from emergency treatment, to prevention, rehabilitation and long-term care,’ explains Peter Kolominsky-Rabas. ‘This lets us find out more and more about stroke, helping us plan even better for patient care in the future.’

Almost one in two patients dies within five years

The current study revealed high rates of fatality and recurrence: Nearly one in two patients died within five years of their first stroke. One in five suffered a second stroke within five years. Women have a slightly higher (49.6 percent) chance of dying compared to men (41.8 percent).

Long-term survival and recurrence rates varied substantially depending on the cause of the first stroke. Patients whose stroke was caused by a blockage in small arteries had the highest chance of survival after five years. The lowest rate of survival was seen in patients who suffered a cardioembolic stroke, which can be caused by atrial fibrillation.

The risk of suffering a further stroke within five years was particularly low in cases of small blood vessels in the brain becoming narrowed (microangiopathy) and when deposits build up in the large blood vessels supplying the brain (macroangiopathy).

Greater chances of survival

The data also indicated a significant improvement in the chances of survival after an ischemic stroke in the past decades in Erlangen, applicable across the board to all sub-types of stroke. This mirrors the situation across Germany. Possible explanations may be improvements in treatment options and dealing with the disease, for example thanks to newly established stroke units.

Within the context of the study, the team of researchers investigated data from 3,346 patients taken between 1996 and 2015 and recorded in the Erlangen stroke register.

Erlangen stroke register: 26 years of research into patient care

Since 1994, the ESPRO has been collecting data on stroke epidemiology, disease progression, patient care and health economics (www.schlaganfall-register.de). This makes it one of the oldest registers of its type in the world, and with 9,100 cases the largest population-based stroke register in Germany. In view of its unique characteristics, it has received funding from the Federal Ministry of Health since 2000. Start-up funding was provided in 1994 by the Bavarian State Ministry of Public Health and Care Services.

ESPRO was the first database in Germany to provide reliable, population-based figures on the distribution and fatality of stroke. This data has proven extremely useful, for example in the current study, for reporting back on trends developing over the years.

As far as possible, all strokes occurring in the city of Erlangen (population in 2020: 113,960) are recorded. The patients whose data are recorded are closely monitored, and their progress tracked after three months, twelve months and then annually until they die. All risk factors, recurring strokes and long-term effects of the disease are tracked from day one. Tracking patients’ progression over the long term like this allows comprehensive research to be carried out into this widespread disease. The data in the register give direct information on the progression of the disease, treatments and patient care, which can then be incorporated into preventative medicine, therapy and planning of patient care. By tracking the entire chain of patient care in this way, researchers can not only identify areas where too much, too little or the wrong type of care is provided, but also assess the effectiveness of long-term care.

Further information:

Prof. Dr. Peter Kolominsky-Rabas
Interdisciplinary Centre for HTA and Public Health at FAU
Peter.Kolominsky-Rabas@fau.de