Threatening or screaming at teenagers may put them at higher risk for depression and disruptive behaviors such as rule-breaking, according to a new study.

"The take home point is that the verbal behaviors matter," Annette Mahoney, who worked on the study, said. She's a professor of psychology at Bowling Green State University in Ohio.

"It can be easy to overlook that, but our study shows that the verbal hostility is really relevant, particularly for mothers who scream and hit, and for fathers who do either one," Mahoney told Reuters Health.

All of the kids in her study had been referred to a community clinic due to mental health or behavioral problems.

Their mothers had to be both verbally and physically abusive to increase the kids' risk for depression and behavior issues. But either kind of behavior alone from a father was sufficient to produce lasting ill effects.

The researchers realize that parents can be trapped in a vicious cycle.

Verbal abuse "has a cyclical nature to it," said Mahoney. Kids with behavioral or mental health problems can be tough to handle, she said.

Not surprisingly, her team found, adolescents whose parents were also physically violent toward them - hitting, choking, or threatening them with a gun or knife - had an even higher risk for mental illness and behavioral problems.

"Parental verbal aggression towards adolescents is just as - if not more - destructive than severe physical aggression, particularly in families seeking mental health services," said Michelle Leroy, also of Bowling Green State University who led the research.

For the study, which was published in the journal Child Abuse & Neglect, 239 troubled adolescents between the ages of 11 and 18 filled out surveys that asked if they were hit, called names, or subjected to other forms of physical or verbal violence over the past year.

Parents of the youths also participated, reporting their behaviors in the same time frame.

Fifty-one percent of the adolescents said they'd experienced serious physical or verbal aggression, or both, from one or two parents.

Having a mother who both screamed and hit increased kids' risk for mental health problems (such as anxiety, depression, and rule-breaking behaviors) to an even greater extent than having a mother who was aggressive in only one way.

In other words, the effect of a mother's verbal hostility may be worsened if she also hits her child, Mahoney said. That may be because teens likely feel more traumatized and threatened when physical violence is a real possibility.

In contrast, screaming by mothers who had not previously escalated to serious physical aggression did not appear to increase the risk of psychological problems among teens getting counseling in this study, Mahoney told Reuters Health.

On the other hand, fathers who were verbally abusive affected the adolescents' mental health, regardless of whether the threats were accompanied by physical violence.

The study's results may indicate that doctors should be on the lookout for verbal aggression at home, particularly in families with an adolescent who may be having mental health or behavioral problems, the researchers say.

Many doctors make it a habit to ask their patients about acts of physical abuse. They should also ask about verbal violence, Mahoney's team adds.

"You have to break the cycle; someone has to crack it open. It doesn't excuse the parents' behavior, but (doctors and therapists) have to not be judgmental (and) get the facts out."-Reuters