Nick Reiner has been open about his addictions, even collaborating with his famous father Rob Weiner about drug rehab and family tensions in the semi-autobiographical movie, “Being Charlie.”

But in the days since the 32-year-old was charged with murder for the stabbing deaths of his parents Rob and Michele Reiner, a picture has emerged of a young man who was also beset by mental health problems.

Tabloid news serviceTMZ reported that Nick has been diagnosed with schizophrenia, a complex psychotic disorder, while the New York Post quoted a family friend as saying Nick’s outbursts at age 11 were so severe he had to be restrained in bear hugs.

Psychologists at Northeastern University said people with depression, anxiety, schizophrenia or bipolar disorder tend to use alcohol and drugs more than the general population. 

And while the professors said they are not in a position to comment on Nick Reiner’s situation, they said that in general, substance use can play a role in delaying diagnosis and treatment of mental health disorders. 

And in very rare cases, they said, drugs and alcohol can tip a mentally ill person into homicidal behavior.

Robert Leeman, professor and chair of Northeastern’s department of public health and health sciences, said using substances can exacerbate symptoms associated with mental health conditions such as schizophrenia and could increase the risk of violence.

It’s especially the case, he said, if the substance use is heavy and the substances are “associated with psychosis, such as cannabis and methamphetamine.”

Carlos Cuevas, a Northeastern professor of criminology and criminal justice and licensed psychologist, said people with mental health diagnoses have higher rates of substance use disorder than those who do not have mental illness.

“There’s a big comorbidity between those two, particularly with certain mood disorders, depression, anxiety and post-traumatic stress disorder,” as well as with psychotic spectrum disorders such as schizophrenia, he said.

People may start using drugs and alcohol to deal with feelings of being out of control, jumpy, depressed or anxious, said Laurie Kramer, Northeastern professor of applied psychology.

“They’re self-medicating,” said Jacqueline Lane, executive director of NAMI of Cape Cod and the Islands, a local Massachusetts chapter of an organization that advocates for the mentally ill and their families.

But starting drug and alcohol use in adolescence, particularly the early teens, also increases the probability of having a mental health disorder down the road, Kramer said.

“It’s a real chicken and egg kind of problem,” she said. “It’s very difficult to disentangle what’s going on here. It’s tough, because some disorders, like schizophrenia, we may not diagnose until age 25.”

Nick Reiner said he started to abuse drugs as early as age 15 and was in and out of drug rehab programs many times in his teens, according to several news accounts including in the New York Times.

Sometimes, when a child has a mental illness, the family and health professionals first focus on the issue of substance abuse “because it tends to be the one that’s most disruptive to the people around them,” Cuevas said.

“People sort of want to tackle that first,” he said.

Since mental health conditions such as schizophrenia or bipolar disorder tend not to manifest until a child is in their late teens or twenties, it’s possible that family and friends may attribute a teen’s problems to alcohol and drug use without noting an underlying condition, Leeman said.

When Nick Reiner entered drug rehab 17 years ago, people who worked with patients with substance abuse disorder and those with mental health illnesses were in separate silos, Lane said.

She said she remembers her intellectually brilliant brother, who died at age 65 a few years ago, being treated separately for alcoholism and bipolar disorder.

“Taking care of alcohol could be a Band-Aid if you are (dealing with) a much deeper issue,” Lane said.

The federal Substance Abuse and Mental Health Services Administration, SAMHSA, says that approximately  21.5 million adults in the United States have a co-occurring disorder, also known as a dual diagnosis of mental health and substance use disorder.

The latest evidence suggests that the two disorders should be treated simultaneously, Leeman said. At a minimum, he said, “the history of substance use should be considered when treating other mental health conditions in order to avoid a course of treatment that will exacerbate substance use.”

While substance abuse alone can lead to psychotic symptoms, “these symptoms tend to be transient and not as intense as what is typically seen with schizophrenia,” Leeman said.

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