An examination of semantic performance in mild cognitive impairment progressors and nonprogressors

OBJECTIVE

Mild cognitive impairment (MCI) is a risk factor for developing Alzheimer's disease (AD), and about half of older people with MCI will progress to AD within the next 5 years. The aim of the present study was to compare the semantic performance of MCI progressors (MCI-p) and nonprogressors (MCI-np). The hypothesis was that MCI-p would present with poorer semantic performance relative to MCI-np at baseline, indicating that semantic deficits may increase the risk of future decline toward AD.

METHOD

Fifty-six MCI participants (aged 65-89) from the Consortium for Early Identification of Alzheimer's Disease-Quebec study were analyzed, with 18 progressing and 38 remaining stable over 2 years. Analysis of covariance assessed their initial semantic and nonsemantic cognitive performance, and mixed analyses of variance gauged longitudinal patterns of cognitive decline at the 2-year follow-up.

RESULTS

In the semantic domain, MCI-p performed significantly worse than MCI-np at baseline on two semantic tests (category fluency and object decision). In other cognitive domains, MCI-p performed worse than MCI-np on a test of executive functions (cognitive flexibility) but showed similar performance on a test of episodic memory. There were no significant differences between groups in the rates of progression on semantic tests over the 2-year period, but a steeper decline was observed in MCI-p at follow-up on tests of global cognition, episodic memory, and processing speed.

CONCLUSION

This suggest that MCI patients who present with semantic memory impairment in addition to episodic memory impairment are at greater risk of future progression to AD. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Intellectual Profiles of Clinic-Referred Preschoolers

Intellectual impairments in preschoolers have been widely studied. A regularity that emerges is that children's intellectual impairments have an important impact on later adjustments in life. However, few studies have looked at the intellectual profiles of young psychiatric outpatients. This study aimed to describe the intelligence profile of preschoolers referred to psychiatry for various cognitive and behavioral problems in terms of verbal, nonverbal, and full-scale IQ and to examine their association with diagnoses. Three hundred four clinical records from young children aged under 7 years and 3 months who consulted at an outpatient psychiatric clinic and who had one intellectual assessment with a Wechsler Preschool and Primary Scale of Intelligence were reviewed. Verbal IQ (VIQ), Nonverbal IQ (NVIQ), and Full-scale IQ (FSIQ) were extracted. Hierarchical cluster analysis using Ward's method was employed to organize data into groups. The children had, on average, a FSIQ of 81, which is significantly lower than that expected in the general population. Four clusters were identified by the hierarchical clusters analysis. Three were characterized by low, average, and high intellectual ability. The last cluster was characterized by a verbal deficit. Findings also revealed that children's diagnoses were not related to any specific cluster, except for children with an intellectual disability with, as expected, low abilities. Children referred to an intellectual assessment in an early childhood mental health clinic showed an altered intellectual development, more specifically in the verbal domain.

Comparison of the Wechsler Preschool and Primary Scale of Intelligence-Third Edition and the Leiter-R Intellectual Assessments for Clinic-Referred Children

A review of clinical records was conducted for children with developmental, emotional, and behavioral difficulties who were assessed with both the Wechsler preschool and primary scale of intelligence-third edition (WPPSI-III^CDN; Wechsler, 2004) and the Leiter international performance scale-revised (Leiter-R; Roid & Miller, 1997) within the same psychological evaluation. Forty children, ages 3–7, were included in this study. Pearson correlations showed that the IQ scores of the two instruments are strongly related (r > .70; p < .001). However, paired t-tests showed that overall Leiter-R scores (M = 99.03) were significantly higher than WPPSI-III^CDN scores (PIQ; M = 82.28, FSIQ; M = 75.24) (p < .001). The discrepancies between the instrument’s scores were clinically important as the use of only one of the two instruments could result in misclassification of child intellectual ability. These results should prompt professionals working with this clinical population to be cautious when using results from a single instrument in a child’s intellectual evaluation.