Mild cognitive impairment (MCI) is a condition in which a person has problems with memory, language, executive function and visuospatial skills that are noticeable to others and can be observed in neuropsychological tests, but do not interfere with everyday activities. People with MCI often develop Alzheimer’s disease (AD).
Factors contributing to the onset of MCI include neurodegenerative disorders (AD-related and other), vascular cognitive impairment, somatic diseases (e.g., hypothyroidism and anaemia), medication side-effects, psychiatric illness, Parkinson’s disease, HIV-related disorders, alcohol and substance abuse. The main risk factor of MCI is age, followed by BMI, modifiable cerebrovascular risk factors (diabetes, hypercholesterolaemia and hypertension), sex (higher prevalence in men), educational level (higher education has a protective effect) and other psychosocial covariables.
Diagnosing MCI involves assessment of cognition status based on the history of symptoms and a mental status examination. Impairment in functional activities is the factor distinguishing dementia from MCI. Deficits in memory, language, problem solving and/or visuospatial skills are examined, which allows distinguishing two MCI subtypes: amnestic MCI (aMCI) and non-amnestic MCI (naMCI), each of which can be further characterised by the presence of symptoms unrelated with memory (single-/multiple-domain aMCI or naMCI).
Aetiology is best diagnosed with MRI or PET imaging. Rapid progress into dementia can be predicted based on the severity of memory impairment, findings from imaging examinations and carrier status of the ApoE-ε4 genotype associated with AD.
There is no widely recognised pharmacological treatment effectively delaying the progress of MCI into dementia. The comorbidities of MCI include conditions common in the elderly (overweight/obesity, cerebrovascular risk factors), but also psychiatric illness and multiple sclerosis.
The Epiomic™ database contains a forecast of the prevalent case load for MCI in males and females, as well as patient population broken down into the two subtypes of the disease. Moreover, a forecast of MCI patient populations carrying the possible ApoE genotypes is available to support studies of the association between MCI and AD.