Self-awareness of cognitive functioning in schizophrenia

Abstract

Poor awareness of psychiatric symptoms is associated with schizophrenia. It is unclear whether this lack of insight extends to the cognitive impairment that affects at least 85% of people with schizophrenia. Given the increasing efforts to develop treatments for cognitive impairment, and the link between awareness of disability and treatment compliance, it is important to understand whether people with schizophrenia have awareness of their cognitive deficits. Ratings of cognitive functioning from 185 outpatients diagnosed with schizophrenia, their clinicians' ratings and objective neuropsychological test results were compared in the following cognitive domains: attention, nonverbal memory, and verbal memory. The results indicated that there was poor concordance among the three assessments. Patients did not agree with their clinician's assessments and did a very poor job of accurately classifying their cognitive status. However, clinicians were also poor at classifying cognitive status consistent with neuropsychological test results. The implications of these findings for understanding insight in schizophrenia are discussed.

Introduction

Individuals diagnosed with schizophrenia spectrum disorders have significant cognitive deficits, especially in the areas of attention, memory, and problem solving (Gold and Harvey, 1993). Because these cognitive deficits have been linked to poor functional outcome (Green, 1996), there is considerable interest in developing treatments for cognitive impairments. As pharmacological and behavioral therapies for cognition become more widely available, it will be important for patients to understand how they can benefit from treatment. Awareness of need for treatment is predictive of compliance with treatment, prognosis, social and occupational functioning, and better outcome in schizophrenia Young et al., 2003, Schwartz et al., 1997, Schwartz, 1998. Therefore, it becomes necessary to understand whether people with schizophrenia have awareness of their cognitive deficits. Unfortunately, this is a poorly understood construct.

To date, studies of awareness in schizophrenia have focused on insight into the presence of psychotic symptoms (Amador et al., 1991). Research demonstrates that awareness into psychotic symptoms is generally poor, and it is most impaired in people with greater amounts of positive symptoms Amador et al., 1993, Carroll et al., 1999, Smith et al., 2000. It remains largely unknown whether people with schizophrenia have awareness into their cognitive deficits. It is important to gather information about insight into cognitive deficits in schizophrenia because people with schizophrenia who are aware of their relative cognitive impairments are more likely to be motivated to receive treatment.

As treatments for cognitive impairment in schizophrenia become more widely available, mechanisms for referral will need to be developed. If patient insight into deficit is good, they can be better relied upon to monitor need for and effectiveness of treatment. However, if patient insight is poor, there will be more onus on clinicians to assess who would benefit from treatment. Because the psychiatrists who administer pharmacological treatments for cognition have limited time with patients and the mental status examination that they are trained to use may not pick up the more subtle deficits, it would be useful for the rehabilitation clinicians, who have more extensive patient contact, to share their assessment of patient cognition. These clinicians typically have masters and bachelor level education that often does not include formal training in cognitive assessment. In the absence of formal neuropsychological test data to inform about the presence of cognitive deficits, clinicians will need to rely on their informal assessments based on evaluation of everyday functioning. However, the accuracy of such assessments is undetermined. If clinicians overestimate their client's cognitive abilities, or fail to recognize the presence of cognitive impairment, they will not refer for treatments that could potentially benefit their clients. On the other hand, if they ascribe cognitive impairment when there is none, patients may be referred for a treatment they do not need.

Despite a large research on cognitive deficits and lack of awareness about positive symptoms, the perception of people with schizophrenia about their own cognition and their awareness/unawareness of cognitive deficits are understudied. Furthermore, the accuracy of informal assessments of cognition made by clinicians is not known. The purpose of this study was to investigate the accuracy of clients' perception of their cognition, and to investigate the accuracy of their clinicians' evaluations of their cognitive functioning, by comparing these assessments to objective neuropsychological measures.