Over the past 20 years the likelihood that men will suffer a stroke later in life has decreased by more than 30 percent. For women of the same age the risk has not changed. The risk factors for having a stroke and the use of medication to prevent it have increased for both groups. Furthermore, new factors linked to the probability of suffering a stroke have been discovered. This has been shown by the PhD research carried out by Renske Wieberdink, based on results of the large-scale Rotterdam ERGO study, for which she will receive her doctorate on Thursday 1 March.
In the Netherlands, approximately 40,000 people are admitted to hospital annually suffering from a stroke. This is acute damage to the brain caused by clogging or a tear in a blood vessel. In recent years, substantial attention has been paid to the prevention of cardiovascular diseases, for example, guidelines have been drawn up for physicians to treat risk factors such as hypertension, high cholesterol and diabetes. It appears from Wieberdink’s research that people in the Netherlands have become unhealthier resulting in high blood pressure and overweight being more common than in the 1990s. Physicians increasingly prescribe medication to reduce the risk of stroke. This includes, for example, blood thinners and cholesterol-lowering drugs.
It is striking that the likelihood that men will suffer from a stroke later in life has decreased by more than 30 percent since 1990. For women of the same age the risk has remained the same. Renske Wieberdink: “A possible explanation is the fact that physicians are alert to the dangers for men while they are inclined to underestimate the risk for women. A positive development is that over the past years smoking has decreased among men. Whether this development is the actual cause for the decrease will have to be investigated further. It is of great importance that the risk factors for strokes among women are also adequately identified and treated.”
To gain a better understanding of the occurrence of strokes, she also studied other factors potentially associated with the risk of stroke. Special measurements on the blood vessels of the retina showed that as the diameter of the draining veins increases the probability of a stroke increases. Another factor linked to the risk of a stroke is age-related macular degeneration, a condition that affects the central vision. Elderly people with a severe form of this condition have a higher risk of getting a stroke. Approximately 1.5 percent of the Dutch population aged 55 and over suffers from this form of macular degeneration.
For her research Wieberdink made use of Erasmus MC’s ERGO (Erasmus Rotterdam Health Study) study, one of the largest epidemiological studies in the world. The study monitors 15,000 inhabitants of the Rotterdam district Ommoord aged over 45 years.