Cognitive Deficits Among Older Adults With Schizophrenia

Purpose: The purpose of this study was to examine the cognitive profiles of older adults with schizophrenia and/or schizoaffective disorders, with the goal of developing tailored interventions deliverable by nurses in order to help this population attain improved outcomes. Cognitive impairments are the core feature of schizophrenia, and they impede the treatment and recovery of people with schizophrenia. Cognitive impairments typically begin early among individuals—before behavioral symptoms are developed and consistently observed in the context of aging. Treating these impairments generally involves antipsychotic medication, but this treatment has not been effective. Prior studies addressing the improvement of cognitive impairments have targeted the effect of premorbid cognitive functioning on functional outcomes early in life. Few studies in the literature have targeted cognitive functioning in older adults with schizophrenia.

Methods: Eighteen older adults (i.e., age ≥ 50 years) diagnosed with schizophrenia or schizoaffective disorders were drawn from a randomized controlled trial that was designed to test the effect of aerobic activity on the cognitive functioning of older adults with schizophrenia. The cognitive function of these older adults was measured by the Wechsler Abbreviated Scale-II of Intelligence (WASI-II) and the Montreal Cognitive Assessment (MoCA). The WASI-II computed a full-scale intelligence quotient (IQ) and two composite quotients for two indices: verbal comprehension index (VCI) and perceptual reasoning index (PRI). A total MoCA score was computed. A MoCA cutoff score of less than 26 suggests cognitive impairment. Descriptive statistics, t-tests, and Pearson correlations were used to analyze this data, collected at baseline, with the SPSS statistical package for Windows.

Results: Among the 18 older adults with schizophrenia, six (33.3%) were male, and 12 (66.7%) were female. Their mean age was 60 years (SD = 8.02) at first entry. Nine (50%) of these older adults had either completed high school or obtained their GED. Their average IQ was 94.22 (SD = 10.68), which indicates average to low-average IQ. The PRI and VCI were 88.89 (SD = 11.99) and 100.06 (SD = 11.18), respectively. The mean MoCA score was 26.11 (SD = 1.81). Seven (39%) of the older adults scored below the cutoff for cognitive impairment (i.e., MoCA < 26). The relationship between the MoCA score and current IQ was not statistically significant (r = 0.105, p = 0.678). Moreover, the MoCA and IQ scores did not differ in a statistically significant fashion with respect to gender, education, and age.

Conclusion: Our results demonstrate the cognitive impairment of sample of older adults with schizophrenia and/or schizoaffective disorders indexed by IQ and MoCA scores. Two scores (i.e., PRI and VCI) suggest that the nonverbal deficit was greater than the verbal deficit among our participants. These results warrant further investigation of clinically appropriate cognitive measures. Moreover, nurse researchers can—and should—develop interventions tailored to the cognitive functioning of specific individuals with schizophrenia and/or schizoaffective disorders—especially those who are older adults—to help them better manage their illness and recovery. Indeed, 39% of our participants exhibited cognitive impairment based on their MoCA scores. Therefore, in light of the global burden of a growing, aging population, nurses and other clinicians should screen the progression of cognitive impairment among older adults with schizophrenia.