The higher the latitude, the higher the prevalence of suicide in Alaska, said a study that analyzed state records from 2003 to 2011.
For every 5-degree increase in northerly latitude, suicide rates increased 18 percent, said the study, published earlier this month by the Alaska Department of Health and Social Services’ Section of Epidemiology.
Lack of daylight in far-north areas of Alaska may have little to do with Alaska’s grim statistics, said the study. Suicides in Alaska and elsewhere in the Circumpolar North are not clustered in the winter months, past analysis has found. To the extent that there is a seasonal pattern, the increases come in late spring and early summer, according to several statistical studies, the latest report pointed out.
The correlation between latitude and suicide rates creates new questions, said study co-author Deborah Hull-Jilly, a program manager at the epidemiology section.
It is possible that people living at higher latitudes could face greater difficulty, with geographic distances between communities and the corresponding feeling of isolation, or that there is a “survival factor,” including the availability of medical aid, she said. “Is it more an issue with isolation and mortality rather than light and dark?” she said.
Alaska: Second-highest suicide rate in U.S.
As of 2010, Alaska has the nation’s second-highest suicide rate, according to the Centers for Disease Control. Only Wyoming, with a suicide rate of 23.2 suicides for every 100,000 people, had a higher rate than Alaska’s 23.1 per 100,000 people, according to the CDC. Alaska’s suicide rate for the 2003-2011 period was 21.6 per 100,000 people, compared to a national average of 11.3 per 100,000 for the period, CDC records say.
Hull-Jilly and her co-author, medical student Erik Woebler, used multiple-regression analysis to examine factors associated with 1,325 suicides during the study period. Because latitude has been considered a suicide-linked factor in past studies — dating back as early as 1897 — they included it as one of the Alaska factors to analyze. Due to the size of the state, Alaska has a wide range of latitudes, from 51.8 degrees to 71.3 degrees, they point out in their study.
Other significant factors correlating with Alaska suicides, they found, were community size and percentage of Native residents.
Rural villages outside of regional hubs and without road connections had the highest suicide rates, while cities had the lowest rates.
Suicide rates among Alaska Natives higher than amongst of non-Native Alaskans
Another particularly strong factor was communities’ ethnic makeup. For every 10 percent increase in Native population, suicide rates were 13 percent higher, the study found.
In rural communities off the road system, a 5-degree increase in latitude correlated to a 52 percent higher suicide rate, their analysis found.
The new study was an outgrowth of an earlier report, published in 2012, that analyzed suicides from 2003 to 2008. That report, also co-authored by Hull-Jilly, found that suicides accounted for 65 percent of all violent deaths in Alaska during the period, that suicide rates among Alaska Natives were more than twice that of non-Native Alaskans and that the highest rates were among Alaska Native men aged 20 to 29 and among residents of Northwest Alaska.
Closer examination of the factors associated with those statistics is important, Hull-Jilly said. “We need to know what are the impacts of these variables so that we can start doing more prevention,” she said.
Contact Yereth Rosen at yereth(at)alaskadispatch.com