Background
Schizophrenia is a chronic disease of the body and mind that affects 1% of the population. About one-fifth to one-third of all patients with schizophrenia do not respond adequately to drug treatment and that have been consistent over time. Definitions of this group have long been hampered by a lack of consistency with confusion with chronicity. Clozapine has shown superior efficacy and this has been replicated consistently.
Aim and objectives
Because of the high prevalence, importance, and inconsistency of schizophrenia resistance, the current study aimed to (a) examine the differences between resistant and nonresistant schizophrenic groups in chronic long-stay patients, (b) study the clinical profile of the clozapine-resistant group in comparison with others, and finally (c) determine the predictors of resistant schizophrenia.
Methods
This was a retrospective and cross-sectional study of 95 patients with chronic schizophrenia or schizoaffective disorder, admitted in long-stay hospital wards at the Psychological Medicine Hospital (Kuwait). They were interviewed by Structured Clinical Interview for DSM-IV and diagnosed according to the , 4th ed. criteria. Patients were assessed by the Brief Psychiatric Rating Scale (BPRS), Positive and Negative Syndrome Scale (PANSS), Clinical Global Impression Severity (CGIS) scale, and Mini-Mental State Examination. Sociodemographics, clinical characteristics, and the history of treatment were determined. Schizophrenia resistance was formulated according to modified Kane’s criteria, which include the following: BPRS score of at least 45; two or more of positive symptoms score of at least 4 (suspiciousness, hallucinatory behavior, conceptual disorganization, and unusual thoughts); CGIS score of at least 4 (moderate to extremely ill); previous failure on two antipsychotic trials of different categories of the full therapeutic range (≥1000 mg of chlorpromazine equivalent) and for at least 3–6 months’ duration; and finally, no preceding good function for at least 2.5 years in the last 5 years.
Results
Thirty-six patients fulfilled the criteria of schizophrenia resistance (37.8%). There was a significant shift in the drug regimen prescribed, with the prescription of more atypical antipsychotics, especially clozapine, with repeated failure of previous drug trials. The only significant difference between the resistant and the nonresistant group was in the psychopathological severity, indicated by higher scores on PANSS, and CGIS scores. Age younger than 40 years and early onset age of schizophrenia (<20 years) were powerful predictors for schizophrenia resistance; other sociodemographic and clinical characteristics lacked significant predictive value.
Conclusion and recommendation
Younger age and early-onset schizophrenia are considered poor prognostic factors. Early aggressive management of schizophrenia may help eliminate chronicity as well as resistance. Research on the biological predisposition for schizophrenia resistance including the clozapine resistance group is required.