A study published in the Journal of Internal Medicine (JIM) has shown that elevated levels of the protein albumin in the urine (albuminuria) may be an important predictor of dementia risk. Scientists from Sweden and the Netherlands analyzed data from 133,000 elderly people without signs of the disease and found that even moderately high albumin levels increased the likelihood of dementia by 25 percent, and severe (high) levels increased the likelihood by 61 percent.
Think of your kidneys as a very smart filter for your blood. Normally, they keep all the good stuff, like the protein albumin, in and only let out the bad stuff. But if that filter starts to leak, the protein ends up in your urine. And here's what's interesting: Scientists have found that this “leak” in your kidneys can be an early warning sign of future brain problems, such as the risk of dementia (loss of memory and thinking skills). The more your kidneys leak, the higher your risk.
Scientists believe this link is because the brain and kidneys are closely connected by a network of tiny blood vessels. Damage that begins in one organ (for example, the kidneys' blood vessels lose their ability to filter proteins effectively, leading to albuminuria) often affects the other. Similar processes can occur in the blood vessels of the brain, disrupting blood flow and weakening the protective barrier between the blood and nervous tissue. This may be a sign of systemic problems, such as microvascular damage and chronic inflammation, that affect both organs.
To understand how this is connected, imagine the blood vessel system in your body as a network of roads. Both the brain and the kidneys are fed by a multitude of tiny “roads” – capillaries. If these “roads” begin to collapse in one “area” (in the kidneys), this often means that there are problems with them in other places, for example, on the way to the brain. Because of this, the “supply” of blood to the brain worsens, and its “protective wall” (a special barrier that keeps harmful substances from the blood) weakens. In other words, a problem with the kidneys is not the cause, but rather a symptom of the general poor condition of the “roads” throughout the body.
This is particularly true in vascular dementia, which is often caused by high blood pressure, diabetes, or stroke. These disorders can lead to inflammation, the leakage of toxins, and the accumulation of abnormal proteins in the brain.
Diseases like high blood pressure and diabetes put a strain on blood vessels throughout the body. As a result, something harmful can leak into the brain, causing a buildup of “protein debris” that prevents cells from functioning properly and communicating with each other.
Scientists believe that a urine albumin test could be a simple and inexpensive way to identify people at increased risk of dementia early, long before cognitive symptoms appear, allowing for timely preventive measures. It is important to note that the study found an association, not a direct cause-and-effect relationship, and albuminuria is a risk marker that indicates systemic health problems.
In fact, this simple urine test can be a kind of “alarm signal” for the brain. It is very important to understand: this does not mean that protein in the urine causes dementia. It is more like smoke from a fire: smoke itself is not a fire, but it definitely indicates that something is burning somewhere nearby. Similarly, protein in the urine is not the cause of the disease, but an important sign that there are problems with the blood vessels in the body, which can also affect the brain. By detecting this “smoke” early, doctors and patients get a chance to take action (for example, control blood pressure, sugar, change lifestyle) to prevent a “fire”.
