By Stephanie Stahl

PHILADELPHIA (CBS) — Robin Williams had a long history of depression and substance abuse, which can lead to suicide.  3 On Your Side Health Reporter Stephanie Stahl has more on his age possibly being a factor too.

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Williams was 63-years-old.  Experts say the suicides among older adults is more than 50 percent higher than the rate for the nation as a whole, much of that related to depression.  A representative said Williams had recently been battling severe depression.

He joked about his demons.  Funny man Robin Williams had a dark, troubled side.  He was among nearly 15 million Americans who struggle with major depression each year.

About a third of people who are depressed also have issues with alcohol or drugs.

“Substance abuse in combination with depression can be a pretty lethal combination,” said Matthew Wintersteen, a Psychologist with Thomas Jefferson University.  He says therapy and medications can effectively treat depression.  It’s more complicated when combined with bi-polar issues, which Robin Williams also reportedly had, along with a history of substance abuse.

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“They may drink alcohol or use drugs as a method to escape from the stress of reality in life.  And in combination with each other we know there’s a significant increased risk for suicide,” said Wintersteen.

Of the 34,000 suicides committed annually, two thirds are attributed to depression.  About half of all suicides occur in men, ages 25 to 65.

Doctors say it’s important to talk about mental health issues, and let people know there’s help.  Warning signs for depression include changes in eating or sleep patterns.  Experts say people who commit suicide often talk about wanting to die.  There is a round the clock National Suicide Prevention Lifeline.  That number is 1-800-273-TALK.

National Suicide Prevention Lifeline-

Depression Information-

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Pennsylvania Adult/Older Adult Suicide Prevention Coalition-

Stephanie Stahl