Schizophrenia: a 'negative' challenge.

A new study provides support for an emerging -- or, more precisely, a re-emerging -- view of schizophrenia as a mental disorder comprising two distinct clusters of symptoms that combine differently in each sufferer.

One set of symptoms involves psychotic features, such as hallucinations and delusions; the other consists of signs of pervasive problems in dealing with others and holding down a job. The latter category, referred to as "negative" or "deficit" symptoms, has attracted much research in the past decade. But rating scales for negative symptoms vary substantially and hinder efforts to understand the nature and frequency of schizophrenia's "deficit syndrome," say psychiatrists Wayne S. Fenton of Chestnut Lodge Research Institute in Rockville, Md., and Thomas H. McGlashan of Yale University.

Still, the presence or absence of deficit symptoms, based on broad definitions now in use, proves a better long-term predictor of how a schizophrenic individual will function than to the signs of psychosis, Fenton and McGlashan report in the March ARCHIVES OF GENERAL PSYCHIATRY.

Negative symptoms include emotional unresponsiveness, lack of communication with others, few movements or gestures and absence of interest in social activities.

The researchers applied eight rating scales for negative symptoms to clinical assessments of 187 schizophrenic patients made upon admission to Chestnut Lodge, a private psychiatric hospital. Clinicans conducted follow-up evaluations of each patient an average of 19 years later.

The broadest rating scale diagnosed 75 patients as having serious deficit symptoms; the narrowest scale yielded 11 patients with a cluster of negative symptoms.

A promising rating device, developed by psychiatrist William T. Carpenter Jr. of the University of Maryland in Baltimore and his colleagues, separates primary from secondary negative symptoms, according to Fenton and McGlashan. Unlike secondary symptoms, primary symptoms last for at least one year and do not stem from anxiety, depression, antipsychotic medication or social isolation experienced as a result of psychotic symptoms. Based on Carpenter's scale, 46 Chestnut Lodge patients exhibited primary deficit symptoms, the researchers maintain. These people generally fared poorly.

More than 70 years ago, German psychiatrist Emil Kraepelin separated schizophrenia (which he called dementia praecox) into two maladies roughly comparable to psychosis and primary deficit symptoms, notes Carpenter in a commentary accompanying the Chestnut Lodge study. That distinction faded as researchers promoted theories of schizophrenia as either a single disease or a group of related diseases.

The new study may help prod schizophrenia researchers to consider the "vitally important" distinction between primary and secondary deficit symptoms, Carpenter contends.