Photographer:Fotograaf: Joey Roberts
Imagine you, a researcher, are given a bag of money, unlimited time and personnel. What research would you do? Thomas van Sloten would like to test a pill that would improve the tiniest veins in the brains of older patients. There is just one problem: that pill doesn't exist yet.
Van Sloten has just returned from a year in Paris. He carried out research at the Inserm institute into the stiffening of the veins. That is to say, large arteries. Funded by Veni money he is now taking a closer look at the tiniest blood vessels, especially in elderly patients suffering from depression. Because it appears that when the tiny blood vessels no longer function properly, this could promote feelings of depression.
Van Sloten, a physician training to be an internist, is doing epidemiologic research, works with large databases and tries to create statistic links. “This type of study has its limitations, setting up a study with patients would be preferable, but there is no medicine to repair the tiny blood vessels in the brain.”
There are tablets against high blood pressure that improve circulation in the larger veins, says Van Sloten. And as all the veins are connected, this could also improve the functioning of the tiny veins. But that is an indirect effect, which we know little about.
Someone who is depressed can also take antidepressant medication, but they don't work as well for the elderly, says Van Sloten. “And if they do work, the risk of a relapse is great. Greater than in other age groups.”
Back to the tiny blood vessels. They take care of more than we thought, says the resident. They ensure that the brain cells receive sufficient blood and oxygen, transport waste matter, and keep the ‘blood-brain barrier’ intact, so that the brain remains free of substances that don't belong there.
How do you know when the circulation is impeded? “You can see that by using a test on the veins in the eyes, which are a good reflection of the veins in the brain. Using a camera you can see if they are too thick or too thin, and with the aid of a flashlight you can check whether they contract properly. The light causes the blood vessels to widen. If they are not working properly, especially in the areas where emotions are processed, then a depression may be lurking.”
Van Sloten would prefer to develop and test medication on approximately five hundred 70-year-olds or older suffering from depression and with poorly functioning blood vessels. He would give half of them a pill that might improve the veins; the other half would receive nothing. In the years that follow, it would appear whether the depression disappears or not. “If it does, the discovery of such a pill would be Nobel Prize-worthy, I think. Because this is not just connected to depression but could also be linked with dementia and strokes.”
He is the first, though, to acknowledge that depression often has multiple causes, apart from just bodily complications. “Loneliness, illness, fear of death all have an influence on one’s spiritual health, but there is probably also a group for whom failing veins play a major role.”
In this series scientists talk about the research they would really like to carry out