Relations between cognitive and symptom profile heterogeneity in schizophrenia

Although numerous studies have consistently revealed cognitive heterogeneit y in schizophrenia, the relationships between such heterogeneity and clinic al phenomenology are not clear. Clusters derived from cognitive heterogenei ty studies may or may not be associated with symptom profile or severity of illness. The purpose of this study was to examine the relationship between cognitive heterogeneity and demographic and clinical phenomenological meas ures. We examined cognitive heterogeneity in schizophrenia by empirically d eriving clusters of patients based upon WAIS-R subtest scores and then anal yzed the way in which these clusters related to demographic and symptom var iables and to DSM-III-R, diagnostic subtypes. Four cognitive clusters were identified that were consistent with previous research. These clusters were differentiated on the basis of educational level and occupational status b ut not on the basis of symptom profile, severity, or DSM-III-R subtypes. Re sults suggest that cognitive measures are independent of severity of the di sorder and phenomenological symptom presentation in these subgroups of schi zophrenic patients.