May 2, 2012 -- More than 50 years of data show that people with schizophrenia who take antipsychotic drugs lower their risk of relapse, a new study suggests.
Relapse rates were 64% in people not taking medications for schizophrenia, while they were 27% in those who were given them for at least a year. Relapse -- meaning symptoms get worse or come back after a period of improvement -- is a common occurrence in people with schizophrenia.
The study also shows that people treated with these drugs are also less likely to be hospitalized or to behave aggressively or violently.
For this review study, scientists analyzed data from nearly 6,500 people with schizophrenia who participated in 65 research trials published between 1959 and 2011.
Since the evidence spanned more than 50 years, researchers were able to include in the analysis older antipsychotic drugs used to treat the condition, such as Haldol and Thorazine, and newer medications known as atypical antipsychotics, such as Abilify, Clozaril, Fazaclo, and Risperdal.
The study is published online in The Lancet.
Weighing Risks and Benefits
Schizophrenia is a brain disorder that affects 2.4 million American adults, according to the National Alliance on Mental Illness, most often before the age of 30. Symptoms of this mental illness can include hallucinations, hearing voices, and/or having delusions.
Although the study shows the medications helped prevent relapse and, to some extent, improved the quality of life in people taking them, researchers also found evidence of their negative side effects.
Still, "we have established that antipsychotic maintenance treatment substantially reduces relapse risk in all patients with schizophrenia for up to two years of follow-up," the researchers write.
An editorial accompanying the research notes that the average follow-up time to evaluate relapse was 26 weeks. But it says this is "only a fraction of the time patients need support from services."
The editorial suggests this is possibly not long enough to observe other negative consequences from long-term use of antipsychotic drugs. It also says that scientists also need to understand why many patients with schizophrenia relapse even though they are sticking to their drug treatment regimen.