Schizophrenia is a severe chronic psychological disorder which adversely influences a person’s ability to think, feel and behave. People suffering from schizophrenia may appear to have completely lost touch with reality and rationality. Although the condition is not common, its symptoms can be extremely debilitating. According to researchers, identifying patients at a high risk of treatment-resistant schizophrenia at the time of their diagnosis can be of significant clinical benefit. An earlier diagnosis can minimize delays in clozapine treatment, especially among those who do not respond to non-clozapine antipsychotics.

Establishing A Link

Limited literature is available about the predictors of treatment-resistant schizophrenia. The study published in The Lancet Psychiatry used a treatment-based proxy for the psychological condition to identify potential predicting factors when patients first visited the hospital with a diagnosis of schizophrenia.

Data was obtained from the Danish National Registry for all adult patients (total of 8,624) older than 18 years of age, with incident schizophrenia diagnosed between Jan 1, 1996 and Dec 31, 2006, with a follow-up until Dec 31, 2010. The main definition of the treatment-based proxy was the earliest instance of either hospitalization for schizophrenia after two periods of different antipsychotic monotherapy or clozapine treatment.

A statistical analysis was then performed to evaluate the association between baseline candidate predictors and treatment-resistance. The predictors included age, socioeconomic background, primary education level, hospitalization of more than 30 days in the year before first diagnosis, inpatient at first schizophrenia diagnosis, comorbid personality disorder, paranoid subtype, psychotropic drug use (antipsychotics, antidepressants, benzodiazepines) and any previous suicide attempts.

Interpretation and Analysis

Treatment with clozapine, the first antipsychotic drug, has been associated with a large number of cases with treatment-resistant schizophrenia – about 20 percent to 60 percent of patients. The association between treatment-resistant and treatment-responsive schizophrenia is not easy to understand since no specific psychopathology of schizophrenia is exactly suggestive of treatment-resistant disease. However, patients with the latter do tend to exhibit more prominent cognitive symptoms and have a more severe psychopathology than those responsive to antipsychotic drugs.

Treatment Resistant Schizophrenia

Treatment-resistant cases are complicated and their complete functional recovery is difficult. Usually poly-pharmacy is required to cater the cognitive, psychotic positive and negative symptoms and to deal with the side effects caused by antipsychotic and comorbid depressive or obsessive-compulsive symptoms. However, in common practice, to treat schizophrenia monotherapy through antipsychotics is done. Treatment resistant patients need combination drugs (antipsychotic agents like combination of clozapine and 2nd generation antipsychotics, mood stabilizers, anti-depressants and experimental substance). The early diagnosis for treatment-resistant patients will let them get treated right away.

The study reveals that various candidate predictors could be of potential use as future prediction models for treatment-resistant schizophrenia. What is of particular significance for clinicians is that the established risk factors failed to predict treatment resistance. This suggests that the condition should be considered as a distinct subtype of schizophrenia rather than a more severe form.