Cognitive deficits undermine schizophrenia recovery. (Attention, Memory, Executive Function).

NEW YORK -- Cognitive deficits in schizophrenia have a marked impact on functional capacity, particularly when it comes to social behavior, Dr. Thomas B. Smith said at a conference on schizophrenia sponsored by Columbia University.

Such deficits can have a ripple effect on recovery by compromising the patients' ability to benefit from rehabilitation interventions, said Dr. Smith of the university.

The upsurge in interest in cognitive manifestations of schizophrenia that has been evident in recent decades represents a return to the original characterizations of the disorder by Emil Kraepelin and Eugen Bleuler, who considered disorganized thinking and associative deficits to be its core features, rather than delusions and hallucinations.

Research in neuropsychology; primarily involving brain function after injury, and cognitive psychology; which focuses on normal populations, has made it possible to define the deficits of schizophrenia and characterize their consequences more precisely; Dr. Smith said at the meeting which was cosponsored by the New York State Psychiatric Institute.

People with schizophrenia "do poorly on almost all tests of neuropsychological function," but the areas of most marked impairment are attention, memory (particularly working and- verbal), and executive function. "These are the core deficits," he said.

One recent study followed 50 medication-stabilized patients at 3-month intervals for 2 years after hospital discharge and found that these three parameters each had a significant impact on social behavior, and that executive function was associated with insight as well.

By contrast, positive symptoms were not correlated with these dimensions of recovery, and negative symptoms affected social behavior, but more weakly than neurocognitive capacity, Dr. Smith commented.

More specifically, working memory was a significant predictor of change in social behavior during a year of recovery: There was a 20% improvement in patients with good working memory; while this area of function was virtually unchanged in those with poor memory.

A similar pattern was apparent in regard to executive function and insight: Patients with good executive function showed little change in insight over the recovery period, while those with deficits registered a substantial decline over time, Dr. Smith said.

Not surprisingly, neuropsychological impairment can make patients less accessible to rehabilitation interventions. Dr. Smith described experience with the Community Re-Entry Program (CREP), a 16-session group therapy protocol that uses behavioral and educational techniques to teach skills for symptom management and to foster an effective treatment alliance.

In a group of 36 patients, those who were randomized to participate in CREP showed significantly greater skill acquisition in the target areas than those who had supportive therapy during the study period, according to Dr. Smith.

But neurocognitive capacity also influenced outcome. Patients who scored above the median in tests of verbal memory had significantly more robust improvements with the CREP program than those patients who had deficits in this area: Some of the patients with poor memory who received treatment, in fact, did no better than more intact controls, Dr. Smith said at the conference.

As has been seen in other research, treatment with atypical antipsychotics was associated with neurocognitive benefits, he said.

Patients in the study who were medicated with risperidone (Risperdal), olanzapine (Zyprexa), or clozapine (Clozaril) had higher mean memory scores than those who received conventional neuroleptics, Dr. Smith said.