In their 30s, these people were twice as likely as their peers to develop metabolic syndrome and have significantly higher levels of systemic inflammation, both markers of higher risk for cardiovascular disease.
They also were three times more likely to have been hospitalized for a psychiatric problem and more likely to report feeling lonely and dissatisfied with life.
Of the 1,037 men and women followed by the Dunedin Multidisciplinary Health and Development Study, 91, or 8.8 percent, had attempted suicide by age 24. These data include all attempts, not just those that resulted in an emergency room visit or hospitalization.
Their young suicide attempts aren't the cause of these troubles, nor are the troubles necessarily an outgrowth of the suicidal behavior, said Sidra Goldman-Mellor, a post-doctoral researcher in the Center for Developmental Science at the University of North Carolina. She has been working on the Dunedin data with Duke University professors Avshalom Caspi and Terrie Moffitt, who is the associate director of the New Zealand study.
"The suicide attempt is a powerful predictor" of later-life trouble, Goldman-Mellor said. "We think it's a very powerful red flag."
Study subjects who had attempted suicide sometime before age 24 had been found to be more impulsive and have more conduct disorders and depression when they were children, well before the attempts. But it is difficult to say where their life-troubles come from, Goldman-Mellor said. "Our study did control for the fact that they have more psychiatric issues, but we may have missed some other underlying factors."
Goldman-Mellor, an epidemiologist who has studied links between economic conditions and suicidal behavior, notes that the New Zealand cohort was coming of age in an economic recession. Given current economic conditions around the globe, including youth unemployment in Spain currently exceeding 50 percent, she is concerned about possible increases in suicidal behavior among youth. "Suicide rates always go up during a recession," she said.
The findings from Dunedin would indicate that a strong response and follow-up to help prevent these later-life issues would be a good investment, she said. Those who had attempted suicide before 24 were 2.5 times more likely to be convicted of a violent crime, consumed twice as much welfare support and were unemployed for twice as many months at the other study participants.
Predicting who is going to attempt suicide is very difficult, but if there's an attempt, "then you can identify them easily, and get them some more comprehensive after-care," Goldman-Mellor said.