Brainstorms V - stress and mental health
Can we get sick from stress?
Today, we are continuing with the topic of stress. But, as we discussed in my previous post, stress isn't an innocuous feeling. Sure, it can be helpful to get by in a tricky situation. However, stress changes our brain (remember the hippocampus?) and it affects our capacity to think and remember things. And if it changes how we think, can it change who we are? This question is enough to start a philosophical discussion that can take us several posts. What really makes us who we are? Is our identity fluid or fixed? Can we change all our personality traits, or are there some that are fixed? Can external factors (like stress) change who we are? Can a psychiatric disorder change who we are? Now you have something to talk about with that intense friend of yours; you're welcome.
Anyway, back to the topic of stress. We might not know all the consequences stress has on our psyche, but what we do know is that it can make us sick. Stress can affect both our body and our brain. I will talk in this post about diseases of the brain, focusing on psychiatric disorders, which have a strong link to stress, especially depression.
And here we come to what is, in my opinion, the most important thing we should know about stress. Because, sure, it's a bit scary that stress can change our brain. But we can regain our mental habilities once the stress is over. However, overcoming a psychiatric disorder is much more difficult than just giving it time to fade. In fact, don't do that, because it doesn't work and it will most likely get worse.
As always, tracing the connection between a risk factor and a psychiatric disorder is complicated. Stress is only part of the general picture and it’s likely that only people with a genetic predisposition develop a psychiatric disorder due to stress. However, several indications point to stress as an important risk factor for mental disorders, in particular depression and post-traumatic stress disorder (PTSD). First of all, patients with depression have more cortisol – the most (in)famous glucocorticoid of the stress axis – than the rest of the population and they are not able to properly block the production of more cortisol even when the HPA axis (the stress cascade, if you remember) is supposed to end.
Another thing that relates stress to depression is that patients who don't show a regulated HPA axis after treatment with antidepressants have a high risk of having another depressive episode compared to those whose HPA axis is working fine again after antidepressants. Lastly, people from families with high genetic risk for depression who do not have the disorder show intermediate levels of cortisol compared to their depressed relatives and the rest of the population.
When talking about PTSD, many patients who have only PTSD (there are many patients in which depression and PTSD coincide) have lower levels of cortisol compared to the rest of the population. In their case, treatment with cortisol has shown preliminary but promising results in treating these patients.
These facts, although not a definitive relationship between stress and mental disorders, are disquieting if we take into account that stress is increasingly a part of our everyday lives. From single parents trying to manage work and caring for their kids to high responsibility employees who are constantly on call and high school students with the pressure of continual evaluation, stress affects everyone. Work and study are seeping into all parts of our lives, with our email constantly active in the background and the boss only a phone call away. Burnout seems like a normal part of life, a given. But studies are showing that people who constantly work are at higher risk of getting sick and not only with a mental disorder; they are also at higher risk of cardiovascular disease, diabetes and even Alzheimer's disease. Although some of the changes stress has on our brain may be reversible, I don't think anyone would take stress lightly if they knew all the consequences it could have.
Alzheimer's disease is the most common type of dementia among the older generations. Unfortunately, the damages it causes to the brain are irreversible. We generally think that those who have dementia were just unlucky. But what if I told you that Alzheimer's is not completely random? Yes, I'm sorry to say that stress can also mess us up in this regard. But how?
Patients that have suffered chronic stress or trauma are more likely to suffer from Alzheimer's. It isn’t 100% clear how stress and Alzheimer's are related, but the possible culprit might be the microglia, the immune system of the brain. These cells, the microglia, are usually helpful to the neurons by removing rubish that accumulates in our brains. If over-activated by stress, however, they can have problems performing their duties and leave the detritus that helps in the progression of Alzheimer's in the brain. In this situation, they can also produce an asphyxiating environment for neurons, contributing to the loss of cells that happens during Alzheimer’s.
So how can we avoid chronic stress? Well, that’s not an easy answer as the exact strategy depends on each person, their preferences and their relation to work. The first thing, though, is to set boundaries. Define the time that you are going to spend on the activity that stresses you and stay away from things related to it after the allotted time. Log out of your email, switch off your work phone if possible, put away your books when you are done studying. You can also take the opposite approach and define a time for your hobbies. Blurring the line between work and private life is very easy, that's why we need to set some rules. If you want more tips about how to manage these boundaries, you can listen to this episode of Work Life with Adam Grant: When Work Takes Over Your Life.
We can also help our hippocampus out - the brain region that was strongly affected by stress - by doing sport. Walking for approximately 1 h a day is enough to increase the volume of the hippocampus which, if you remember, shrinks during chronic stress. Regular physical activity can also act as an antidepressant and helps against cardiovascular disease, as we all know, plus diabetes and dementia. There are, of course, other things you can do to manage stress. However, if the problem is severe, please visit a psychologist who can give you tips that better apply to you.
Well, we are done for today. I've arranged the main take-home messages right here:
- Stress can make us sick: brain disorders, cardiovascular disease and diabetes are some examples
- Being stressed is not a death sentence - stress predisposes to disease, but we can regulate our stress levels. And maybe your genetic background can save you, but you might not want to put all your eggs in that basket.
- You can try to mitigate chronic stress by unplugging from the things that stress you and dedicating time to your hobbies or preferred relaxing routines. Sport is always a good option ;)
I hope I didn't scare you too much; just enough so that you do 10 min of daily meditation, maybe? And remember to stay tuned if you want to know more about mental health!
Oh and by the way, especially during these trying times, please remember to check on that friend of yours who is having a rough time. Maybe they got fired because of COVID-19, maybe they were just now transitioning to a new job that is no longer available, maybe they are living alone or they are stuck with someone toxic in their apartment. This is hard for everyone, so let's extend our digital hand to support those we care about. If you need more than your friends' help, please keep in mind that many psychologists are still tending to patients via virtual calls.
1. Kloet, E. R. de, Joëls, M. & Holsboer, F. Stress and the brain: from adaptation to disease. Nat. Rev. Neurosci. 6, 463–475 (2005).
2. McEwen, B. S. Brain on stress: How the social environment gets under the skin. Proc. Natl. Acad. Sci. 109, 17180–17185 (2012).
3. Bisht, K., Sharma, K. & Tremblay, M.-È. Chronic stress as a risk factor for Alzheimer’s disease: Roles of microglia-mediated synaptic remodeling, inflammation, and oxidative stress. Neurobiol. Stress 9, 9–21 (2018).
4. Work Life with Adam Grant: When Work Takes Over Your Life.
5. Alzheimer's Disease Fact Sheet, NIH: https://www.nia.nih.gov/health/alzheimers-disease-fact-sheet