Related Experiment Video
Updated: May 4, 2026
A Machine Learning Approach to Design an Efficient Selective Screening of Mild Cognitive Impairment
Published on: January 11, 2020
Early identification and heritability of mild cognitive impairment
William S Kremen1, Amy J Jak, Matthew S Panizzon
1Department of Psychiatry, University of California, San Diego, La Jolla, CA, USA, Center of Excellence for Stress and Mental Health, VA San Diego Healthcare System, La Jolla, CA, USA, Psychology Service, VA San Diego Healthcare System, La Jolla, CA, USA, Computational Science Research Center, San Diego State University/Claremont Graduate University, San Diego, CA, USA, Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA, Department of Public Health, University of Helsinki, Helsinki, Finland, Department of Statistics, St Louis University, St Louis, MO, USA, Research Service, VA St Louis Healthcare System, St Louis, MO, USA and Department of Psychology, Boston University, Boston, MA, USA.
Background:
Identifying mild cognitive impairment (MCI) in midlife could improve early identification of Alzheimer's disease (AD). Also, AD is highly heritable, but the heritability of MCI has not been established. We estimated prevalence rates, association with premorbid general cognitive ability (GCA) and heritability for different definitions of neuropsychologically defined MCI in adults in their 50s.
Method:
We examined 1126 twins aged 51-59 years when recruited into the Vietnam Era Twin Study of Aging (VETSA). Six neurocognitive domains were assessed using tests designed to avoid ceiling effects. To differentiate MCI from low overall ability, criteria included adjustment for GCA measured at approximately age 20 years.
Results:
As in older adults, prevalence rates varied widely. Among the lower prevalence rates were some definitions of multiple-domain MCI and single-domain amnestic MCI, which may be less likely than other MCI categories to revert to normal on follow-up. Low prevalence rates in middle-aged adults are also more likely to be valid. MCI was also associated with lower premorbid GCA. Heritability estimates for any MCI and amnestic MCI averaged .40-.48.
Conclusions:
By testing multiple cognitive domains and avoiding ceiling effects, MCI can be identified before age 60 years. Premorbid GCA is a risk/protective factor, but deficits after adjusting for early adult GCA suggest additional processes leading to declining trajectories. Heritabilities were comparable to AD, suggesting MCI as an appropriate phenotype for genetic association studies. Full validation will require follow-up assessments (currently under way). Community-based studies are important for this early identification because adults of this age are unlikely to present in clinics.
Insights
Mild cognitive impairment (MCI) is identifiable in middle age and linked to lower early cognitive ability. MCI heritability is comparable to Alzheimer's disease (AD), suggesting its use in genetic studies.
Area of Science:
- Neuroscience
- Genetics
- Cognitive Aging
Background:
- Early identification of mild cognitive impairment (MCI) is crucial for Alzheimer's disease (AD) intervention.
- Alzheimer's disease (AD) is highly heritable, but the heritability of MCI remains understudied.
- This study investigates MCI prevalence, association with general cognitive ability (GCA), and heritability in midlife adults.
Purpose of the Study:
- To estimate MCI prevalence and heritability in adults in their 50s.
- To examine the association between MCI and premorbid general cognitive ability (GCA).
- To assess the suitability of MCI as a phenotype for genetic studies.
Main Methods:
- Examined 1126 twins aged 51-59 from the Vietnam Era Twin Study of Aging (VETSA).
- Assessed six neurocognitive domains using tests designed to avoid ceiling effects.
- Adjusted for general cognitive ability (GCA) measured in early adulthood to differentiate MCI from low overall ability.
Main Results:
- Prevalence rates for MCI varied significantly across different definitions.
- MCI was associated with lower premorbid general cognitive ability (GCA).
- Heritability estimates for MCI ranged from .40 to .48, comparable to AD.
Conclusions:
- Mild cognitive impairment (MCI) can be identified in individuals under 60 using sensitive cognitive assessments.
- Premorbid GCA is a risk factor, but declining GCA after early adulthood suggests additional pathological processes.
- MCI heritability supports its use in genetic association studies for neurodegenerative diseases.
More Related Videos
06:23The 4 Mountains Test: A Short Test of Spatial Memory with High Sensitivity for the Diagnosis of Pre-dementia Alzheimer's Disease
Published on: October 13, 2016
09:38Generalized Psychophysiological Interaction PPI Analysis of Memory Related Connectivity in Individuals at Genetic Risk for Alzheimer's Disease
Published on: November 14, 2017
Related Concept Videos
01:29Alzheimer Disease l: Introduction
01:22Dementia l: Introduction
01:26Alzheimer's Disease: Overview
The clinical diagnosis of AD hinges on the presence of memory and other cognitive impairments. Biomarkers, such as changes in Aβ...
01:23Alzheimer Disease ll: Pathophysiology
01:29Intellectual Disability
01:30Dementia
The progression of dementia is generally gradual....