Yearning for those long days of summer? Think again. The results of a new study have shown that increased amounts of sunlight have an effect on suicide rates.
In a new study released by BMC Psychiatry, a team of scientists from the Karolinska Institute in Sweden examined all of the suicides in Greenland between 1968 and 2002. The team, led by Karin Sparring Bjorksten, found that 82 percent of the suicides occurred during the daylight months and the rate reached its peak in June. This pattern was particularly apparent in northern Greenland where there is constant daylight from April through August.
Count me in among people that assumed one’s level of happiness generally increases as summer draws closer. I don’t think I am the only one who anxiously awaits summer after months of cold temperatures and miserable weather. So what gives? As noted by Reuters:
“The researchers speculated that light-generated imbalances in serotonin — the brain chemical linked to mood –may lead to increased impulsiveness that in combination with a lack of sleep drives people to kill themselves.
“Light is just one of the many factors in the complex tragedy of suicide, but this study shows that there is a possible relationship between the two,” Bjorksten said.”
The researchers also mentioned insomnia caused by relentless daylight as a possible factor.
And it’s not just suicide; sunshine seems to bring out the homicidal maniacs too:
http://thestatsblog.wordpress.com/2009/04/10/springtime-for-homicidal-mania/
Now, where would that fit in with the SAD (seasonal affective disorder) type of depression. It, allegedly, develops after winter months of shortened light exposure! Maybe it is more about the imbalance caused by living in these extreme environments. One also might question whether or not it is more prominent in natives, as compared to non-natives, of the extreme northern latitudes, involved in the study.
Sincerely,
Michael Langley, MD