A recent study of suicide in Alaska suggests that the rate of intentional, self-inflicted death gets higher the farther north a community is located, though the study's authors say the exact reasons for that remain unclear.
The results of a statistical analysis of data from 2003 to 2011, published in a state Section of Epidemiology bulletin Nov. 6, show a correlation between higher suicide rates and higher latitudes. The bulletin also notes that Alaska's suicide rate is nearly twice the national average and the leading cause of death in Alaska for people ages 15 to 24, according to the most recent national data.
In Alaska, suicide is also a leading cause of total years of life lost before the age of 65, said one of the study's authors, University of Alaska Anchorage graduate student Erik Woelber.
"There's a lot of people who are working really hard to reduce rates in the state. And at the moment, rates have been kind of constant over the last five or six years, at least," Woelber said. "I think that the preservation of human life is one of the highest callings we have as human beings, and that's why this type of research into suicide and prevention is really important."
Woelber and co-author Deborah Hull-Jilly, program manager with the Epidemiology section's Injury Surveillance Program, separated Alaska communities into three categories: cities, hubs and rural. They used a statistical model designed to look at rates among small populations using many variables, Woelber said.
One variable stood out: latitude.
For every 5 degree increase in latitude -- about 345 miles -- the suicide rate jumped 18 percent, according to the model. Alaska spans almost 20 degrees of latitude.
"It's a correlation, and you hear all the time in statistics that correlation is not causation, so it's unclear at this time what is the cause of the correlation," Woelber said. "Usually when people hear about the connection between latitude and suicide they interpret it in terms of lack of sunlight in the winter. In fact, we don't really have a seasonal fluctuation in suicide rates in Alaska over the year."
A more focused study in the future might be able to find the cause, Woelber said. But there still are going to be some more subjective issues that data cannot describe, or risk factors that are under-reported or not accurately reported, he said. As an example, that could include rates of gun ownership or access to social and medical services, Woelber said.
"When you look at suicides, each one of those is a story and each one is different," Woelber said.
Kate Burkhart, executive director of the Statewide Suicide Prevention Council, agreed that there are many reasons why a person might commit suicide and cautioned against reading too much into the latitude connection.
"There are multiple complex factors that can lead a person to that place," Burkhart said. "We try to focus on the whole picture, rather than just one element."
Research has shown a "web of causality" that leads people to suicide, Burkhart said. The recent study shows the importance of resources already invested in northern communities, where the council had seen those increased numbers, she said.
"We still have to be very careful. It's human nature to want to know a single cause," Burkhart said. "It's such a hard issue to deal with, it's easier to think it's somebody else's issue. 'That's not our problem, it happens up north.' The state's goal is that everybody understands their role in the prevention of suicide."