Renshaw discovered research supporting his theory. Doctors from Case Western University, it turned out, were crunching numbers based on a similar hunch about altitude and suicide. In a 2010 study published in High Altitude Medicine and Biology, the Case Western group analyzed suicide rates across 2,584 counties in 16 states and found that suicides start increasing between 2,000 and 3,000 feet in all U.S. regions. The U.S. isn’t a special case – analysis of suicide rates in other countries, including South Korea and Austria, bore similar results.
Psychology research has also made a connection between mental health and elevation.