Can Living at Altitude Lead to Depression?

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Despite being ranked America’s happiest state with ski resorts, stargazing, and mountain trails galore, Utah also has the country’s highest suicide rates. One neuroscientist is calling it the “Utah Paradox” and thinks he has a hunch on why: high altitude — despite its risky virtues — can mess with your brain chemistry. Perry Renshaw’s research was recently featured in a Mic Article and we spoke to the man himself on why sadness might run so rampant at such great heights.

Could you describe the Utah paradox?
Look at any survey published in the last 30 years, and you’ll see there’s a high quality of life associated with living in the mountains. At the same time, if you use the Center of Disease Control data, Utah leaves the nation behind in depression and suicide — there’s more suicidal acts, more antidepressant use. The whole region of the Rocky Mountains has high rates of suicide. So how can it be that we love living there but we have more depression and suicide? We started to focus on the idea of thin air — that partial oxygen is less the higher you go in altitude. And people studying brain chemistry and looking at blood changes in high-level enthusiasts, see the phenomenon of hypoxia.

What is hypoxia and how does it affect some people’s mental health?
Hypoxia simply means low oxygen, and you can have low oxygen for a lot of reasons: because you have asthma, or because the air happens to be much thinner at high altitude. You’re compromising lung function. During hypoxia, the brain has a terrible time making the chemical serotonin. But hypoxia also causes the brain to make more dopamine — which is generally linked to rewarding activities. So depending on your genetics, if you have a predisposition to lower serotonin levels or depression and anxiety, you could trip over the fact that your brain isn’t making as much serotonin, and be affected by the altitude. But if you’re someone who loves coming here and feel at home on the mountains, that’s the dopamine elevation effect explaining why you’re happy to live there.

At what altitude does hypoxia start to affect brain chemistry?
As you go up in altitude, the atmospheric pressure goes down so you have less oxygen than at sea level. Taken to the extreme there’s outer space. But Barry Brenner at Case Western University, who’s also done some research in this, looked at the data and said it’s 2,000 feet — that’s when problem start to appear with increased suicide, and that’s the altitude when our bodies have trouble extracting oxygen for purposes.

Who might this impact of altitude most likely affect? What can they do?
We see the greatest symptoms in people who recently moved to a higher place. If we recruit new scientists, 30 to 40 percent will have a nuance of anxiety or depression. They feel the symptoms. So if you haven’t grown up in the higher elevation areas, it’s quite a profound switch for your body and brain to adjust, and people do experience sadness.

People who should worry more are people who have bipolar disorder — low serotonin will push for more depression, more mania. So if you know you have a depressive or anxiety disorder if you’re planning a trip or moving into a higher altitude state its useful to consider the idea that you mood will change and whoever is providing you care for that should know, and help you stay on top of it.

Do we have other evidence showing how climate or geography can impact brain chemistry?
Look at animals. Japanese researchers showed that as barometric pressure drops, animals display more depressive symptoms. We have a similar system where we make the air thinner with a vacuum pump and what we see in female animals is the thinner we make the air, the more depressed they look the and the less they respond to conventional treatments. So we’re concerned in how this plays out in humans.

Why did you start looking into the link between altitude and depression?
The University of Utah recruited my wife and me from Harvard in 2008, and as part of our transition we started working at the mental illness research clinical center, where the focus was on suicide research. This linked back to work I had done in Boston, identifying changes in brain chemistry with people having mood disorders. We’ve seen change sin brain chemistry consistent to hyperventilation. It’s more of a struggle to get as much oxygen as the body wants. Then, as a newcomer to Utah, everyone is short of breath when they arrive there- that didn’t seem like a good idea for people with mood disorders already.

Could other factors be influencing the high suicide rates?
Suicide is a complex disorder. We’re not saying altitude is the only thing that’s going to influence how you feel when you’re under stress, or are impulsive. We don’t mean to boil it down to one factor. But the advantage is we can ask how can you take care of problems caused by thin air. A lot of factors contribute to depressed mood, but this seems like a particularly easy factor to identify.

How can Utah respond to this?
This is intended to be pro-mountain research, because its only once you identify a problem and what’s causing it that you can fix it. The goal for the next 3 yeas is focus on how can we improve outcomes. Now that we know a lot of people taking antidepressants, we can make those more effective, or get dietary interventions to get the point where they can get well without them.