Paradoxical: The Link Between Mental Health And Oxygen

Dec 12, 2014

Utah has long been touted at being the happiest state in America, while paradoxically ranking amongst the highest in the nation for suicides and anti-depressant use. Long-standing theories on why this trend effects Utah and other nearby states have ranged from cultural influences to rural living and higher rates of gun ownership.

However, University of Utah Professor of Psychiatry Perry Renshaw’s research is showing that something much more basic may behind these somewhat incompatible rankings: altitude.

Neurotransmitter: any of several chemical substances, as epinephrine or acetylcholine, that transmit nerve impulses across a small gap in the brain to a nerve, muscle, or gland.

"I think if you look at the maps they would show these very funny phenomenon of people both largely feeling good but also feeling bad. It really is the mountain areas that are implicated. And, as you can imagine, across the intermountain west there are states with quite different regional variations and cultures. So just looking at oxygen in the air seemed like one simple way to begin to try to understand what might be happening," Renshaw said.

When Renshaw first moved to Utah he says he was shown a map of the United States, plotted on it were suicide rates.

"Because I had this fixation on altitude, we got on the internet and looked up the altitude of states and sort of plotted things out. There was this amazingly strong correlation between altitude and rates of suicide," he said.

Renshaw, who studies neural chemistry using brain imaging techniques, eventually calculated that as much as 25 percent of the variation in rates of suicide across the nation could be uniquely attributed to changes in altitude. Eventually, he decided to focus his research on how high altitudes, and the resulting lower oxygen levels, affect how people’s brains work.

"There are some critical neurotransmitters in the brain that help the brain communicate within itself. One of them is serotonin, and serotonin is the critical neurotransmitter that modulates mood and anxiety. And animals that go up into the mountains or simulated mountainous environments, their levels of serotonin go down quite a bit; they go down very quickly.

Serotonin: a neurotransmitter, derived from tryptophan, that is involved in sleep, depression, memory, and other neurological processes.

And so one would predict  or expect that the people who are either genetically predisposed or don't make quite enough serotonin, that they would experience new onset symptoms of either depression or anxiety."

At the same time, other neurotransmitters are going up…

"Low oxygen also increases the levels of another neurotransmitter, dopamine. And what we think the dopamine does in the brain is it basically regulates anything that one would do that would be pleasurable or enjoyable. So more dopamine generally means feeling better."

These changes in brain chemistry have some profound effects on people with mood disorders, Renshaw says. Those who suffer from anxiety or bipolar disorder on the coast may see their symptoms worsen, sometimes drastically, when they move to higher elevations.

For those who suffer from depression, traditional methods of treatment may not work in the mountains, simply because their brains aren’t producing enough serotonin in the first place.

"If you have normal serotonin levels, you'd release normal serotonin levels into the space between the nerve cells, and what these drugs do is they block the re-uptake of the serotonin. So more of the neurotransmitter sticks around and communicates the serotonin signal. But the experience of being in altitude is that in response to hypoxia, your brain doesn't make as much serotonin so there's less serotonin to block the re-uptake of, so the effects of standard treatments may not be that powerful," he said.

With that knowledge, Rensaw is now trying to find a more effective treatment for depression than the traditional go-tos such as Prozac and Zoloft.

Dopamine: a neurotransmitter in the central nervous system and retina acting within the brain to help regulate movement and emotion.

At the same time, he says elevation isn’t all bad. In a paper currently under review, Renshaw claims increased elevation has a positive impact on those with Attention Deficit Hyperactivity Disorder; a dopamine imbalance.

"In the intermountain west we actually have rates of ADHD that are about half those observed at sea level. So in this case, the effects of altitude and the increasing brain dopamine levels is treating for many people some of their ADHD symptoms."

When he first released his findings, Renshaw says people in Utah tended to be skeptical.

As time has passed and more research has been conducted, Renshaw says other researchers are coming to support his findings. Though better ways of treating depression and other mental health disorders are still on the way, that doesn’t mean doctors can’t use this information. Renshaw says just warning patients of the possible changes to their health before a move to higher altitude can allow them to make sure they have a good support system in place.

"Just some degree of reassurance and education and planning ahead can make a big difference in terms of how people weather a transition," he said.

While altitude may have an impact on depression and suicide, Rensaw says his work doesn’t negate earlier theories about culture’s role in the problem.

"Nothing that we do means the people who study cultural impacts in rates of suicide and depression are incorrect," Renshaw said. "In fact, they're perfectly complimentary and probably additive effects. We're by no means saying that the problem of suicide in Utah is due strictly to altitude, but rather this is one of several factors, one that we find particularly important."

The goal now, Renshaw says is to get enough grants to pay for a clinical treatment program. For now, he says a paradox is still the best way to describe what’s happening in places like Utah.

"I think a paradox is a nice way to think about it because it gives both a good message that we've all sort of observed in terms of our friends and neighbors feeling happy living in the state of Utah, but also makes it clear that for some people it's not a completely happy set of circumstances."