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Newer Drugs Appear to Stem Violent Behavior

Newer Drugs Appear to Stem Violent Behavior
Newer Drugs Appear to Stem Violent Behavior


Duke Health News Duke Health News

DURHAM, N.C. -- Researchers at Duke University Medical Center have found that a new generation of medications called "atypical antipsychotics" can significantly lower the risk of violent behavior in people with schizophrenia who are being treated in community-based centers.

In a two-year study, the researchers found that patients who consistently took one of the newer medications had less than one-third the incidence of getting into fights or engaging in violent actions toward others, compared to subjects who consistently took one of the older antipsychotic medications.

This study is the first to examine the long-term impact of treatment with the newer class of drugs on violent behavior measured directly in the community, under "real world" conditions, the researchers said. Examples of drugs in this newer class include clozapine, risperidone and olanzapine.

The study appears in the latest issue of Schizophrenia Bulletin (Vol. 30, Number 1), a journal of the National Institute of Mental Health. Data were collected by the North Carolina site of the Schizophrenia Care and Assessment Program (SCAP). This study is a multi-center, prospective, observational study that assesses the clinical, functional and service utilization outcomes associated with routine care for persons diagnosed with schizophrenia in five geographic regions of the US. That study is ongoing.

"Violent behavior has many causes, and most people with psychiatric disorders are not violent," said Jeffrey Swanson, Ph.D., associate professor of psychiatry and behavioral sciences at Duke and lead author of the study. "But the consequences of violence are serious and costly in a small minority of individuals with severe and persistent mental illness -- particularly those who stop taking prescribed medications due to adverse side effects and instead use street drugs or alcohol."

The potential for violence in even a small minority of people with untreated psychotic disorders increases public fear, prevents acceptance and inclusion of people with psychiatric disabilities in society, disrupts continuity of care and limits the effectiveness of community-based mental health services, said Swanson. So, the researchers point out, there is a need for better treatment options among those likely to become violent as well as better predictive measures of who is most likely to become violent.

The researchers followed 229 patients with schizophrenia over a two-year period. All were adults with schizophrenia-spectrum disorders who were receiving inpatient or outpatient services in public mental health systems in the north-central region of North Carolina. Slightly more than half of the participants were male. Those enrolled ranged in age from 18 to 71 years old.

Participants were observed at six-month intervals to assess treatment, their social and demographic characteristics, recent psychiatric hospitalizations, substance abuse and violent episodes. The data were compared among those treated with the newer class of atypical antipsychotic drugs, versus those who were receiving either the older, conventional medications (called neuroleptics) or no medications at all.

Rather than attempting to control the treatments provided to individuals with schizophrenia, the researchers chose to instead observe the effects of a range of treatments prescribed to them over time. The "naturalistic" observation of the participants provided a more realistic look at typical care conditions. Previous studies have been limited in their generalizability to the "real world" conditions under which community-based treatment is delivered, as many have focused on the relatively short-term examinations of people being treated as inpatients in hospitals or living in prisons.

Violent behavior was defined as any assault or battery committed against another person specifically involving physical contact intended to harm (such as hitting, shoving, kicking and biting) or threatening another person with a lethal weapon in hand. The behavior was measured in three ways -- via participant self-report, systematic review of outpatient and inpatient medical records (including civil commitment documents and other legal information) and by reviewing records of arrest for violent offenses documented in the North Carolina Department of Justice database.

According to Swanson, even when his team took into account any prior differences in risk factors for violent behavior or selection of medication between the groups, the reduction in violence for those taking the newer medications remained statistically significant.

"Many patients with schizophrenia find the new medications easier to tolerate because there are fewer side-effects," said Marvin Swartz, M.D., professor of psychiatry at Duke and co-author of the study. "Greater tolerability of the medication makes it easier to control symptoms of the disease more consistently and may also help people avoid substance abuse and situations that otherwise can lead to violence."

Older, neuroleptic-type medications have been shown to have frequent side effects that can be uncomfortable for patients, making it more difficult for them to adhere to the drug interventions. Adhering closely to a treatment plan that works is essential, the researchers said, because symptoms of diseases like as schizophrenia are much easier to control if the medication is taken consistently.

The newer medications might have a direct pharmacological effect in reducing both aggression and violence, while also possibly lowering violence indirectly by reducing adverse medication side effects, psychotic symptoms and substance abuse while improving social functioning, Swartz added. However, the drugs are more expensive than the older class of drugs, making them more difficult for patients to afford.

The researchers said that better adherence to the medication is a substantial factor in reducing the risk of violence, as their data show a cumulative effect on reduced violence over time among people who took their medications consistently. Because of this, they assert, atypical antipsychotic medications should be considered an important component of violence risk management for patients with schizophrenia who are living in the community.

In North Carolina, the majority of state mental health hospital admissions are involuntary commitments that are commonly precipitated by threatening or assaultive behaviors in patients with schizophrenia who have experienced either an increase in symptoms or complete relapse of their illness following a period of non-compliance with their medication. In fiscal year 2000, the North Carolina Division of Mental Health, Developmental Disabilities and Substance Abuse spent $285 million dollars on hospital care for those who had been institutionalized. According to the study, this amount is equal to 71 percent of the department's entire annual adult mental health care budget. The same year, according to the study, the North Carolina Department of Corrections spent an estimated $117 million for the incarceration of approximately 5,000 people with primary psychiatric disorders. Of that number, it is estimated that only 9 percent were receiving psychotropic medications while incarcerated.

The Duke researchers assert that, given timely treatment with appropriate medications and other mental health interventions, many people with schizophrenia could avoid hospitalization or incarceration altogether.

Eli Lilly & Company, the manufacturer of olanzapine (trade name Zyprexa) -- an atypical antipsychotic -- provided funding for the study. The researchers did not analyze data on individual drugs, but rather evaluated the data by class of drugs (atypicals versus neuroleptics).

Eric B. Elbogen, Ph.D., of Duke University Medical Center, is also an author on the study.

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