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Many risk factors are tied to suicide; scientists investigate if climate change could be one

A study suggests that suicide rates could climb 0.68% in the US and 2.1% in Mexico per 1-degree Celsius rise in monthly temperatures

CNN  — 

Scientists have cautioned that soaring climate temperatures around the globe could put our physical health at risk, such as with the spread of certain infectious diseases or food shortages.

Now, a new study sheds light on the possible mental health implications of climate change.

The study, published in the journal Nature Climate Change on Monday, suggests that when there are abnormally hot temperatures in a month, there also tend to be higher suicide rates for that month, compared with the suicide rate that occurs when the month has normal average temperatures.

Then, when using the data to make predictions, the study suggests that suicide rates in the United States and Mexico could rise with each 1-degree Celsius increase in a month’s average temperature.

Asking for help

The suicide rate in the United States has seen sharp increases in recent years. Studies have shown that the risk of suicide declines sharply when people call the national suicide hotline: 1-800-273-TALK.

  • There is also a crisis text line. For crisis support in Spanish, call 1-888-628-9454.
  • The lines are staffed by a mix of paid professionals and unpaid volunteers trained in crisis and suicide intervention. The confidential environment, the 24-hour accessibility, a caller’s ability to hang up at any time and the person-centered care have helped its success, advocates say.

    The International Association for Suicide Prevention and Befrienders Worldwide also provide contact information for crisis centers around the world.

    “So we take a specific location and we take a specific month, and we compare cooler versions of that month to hotter versions of that month, and we ask, ‘Are suicide rates different during those two months?’ We indeed find that they are,” said Marshall Burke, an assistant professor in the Department of Earth System Science at Stanford University and lead author of the study.

    “We find a very consistent relationship between temperature increases and increases in suicide risk,” Burke said, adding that the study findings in no way suggest that temperature is the only – or most important – factor associated with suicide.

    “Suicide is a very complex phenomenon. It’s still not that well-understood, and there are many other risk factors beyond climate that are important for suicide risk,” he said.

    Suicide was the 10th leading cause of death overall in the United States, claiming the lives of nearly 45,000 people in 2016, according to the Centers for Disease Control and Prevention.

    Globally, close to 800,000 people die by suicide each year, and 78% of global suicides occur in low- and middle-income countries, according to the World Health Organization.

    A rise of 1-degree Celsius tied to suicide rate increase

    The study included data on suicide rates in the US between 1968 and 2004 from the CDC’s National Vital Statistics System, as well as monthly suicide rates in Mexico between 1990 and 2010 from the National Institute of Statistics and Geography.