A new report from the Substance Abuse and Mental Health Services Administration (SAMHSA) shows a 49 percent increase in emergency department visits for drug-related suicide attempts for women aged 50 and older.

And women aged 40-69 are more at risk of killing themselves than other women, according to new research on age-specific suicide rates between 1998 and 2007. In 2007, this age group made up 60 percent of the 7,328 suicides reported among women.

But why middle-aged women? It could just be a question of numbers: One in four adults in the U.S. has a treatable mental health condition, and middle-aged women are one of the fastest-growing populations in the country.