What is mild cognitive impairment?
Mild cognitive impairment is a state between normal aging and dementia. The person or their family notices a decline, and tests show lower scores than expected for age and education—but unlike dementia, independence in daily life is preserved. The amnestic type, mainly affecting memory, is relatively more likely to progress to Alzheimer's disease; the non-amnestic type affects attention, language or executive function.
How common is MCI, and does it always turn into dementia?
Prevalence figures summarized in the 2018 American Academy of Neurology (AAN) guideline are 6.7% at ages 60–64, 8.4% at 65–69, 10.1% at 70–74, 14.8% at 75–79 and 25.2% at 80–84. Among people 65 and older with MCI, 14.9% developed dementia within two years. Others stay stable or even return to normal.
Evaluation
- Screening tests: the MMSE and MoCA are common. In the MoCA development study, sensitivity at a cutoff of 26 was 90% for the MoCA versus 18% for the MMSE.
- Detailed assessment: neuropsychological testing and evaluation of daily function.
- Finding causes: check for treatable causes such as thyroid problems, low vitamin B12, depression, sleep apnea and medication side effects, with brain MRI and biomarker tests if needed.
For how test accuracy works, see reliability and validity of measurement.
Management
The AAN guideline found no medication proven to work for MCI, recommends regular exercise (Level B) and says cognitive training may be considered (Level C). Cutting back on drugs that affect thinking, managing vascular risk factors like blood pressure and diabetes, addressing hearing loss and staying socially active all matter. For brain changes in Alzheimer's disease, see Alzheimer's pathology and the amyloid hypothesis.
This article is general health information and is not a substitute for diagnosis or treatment. If symptoms persist, see a doctor.
FAQ
- Is forgetting names a sign of MCI?
- Occasionally forgetting names is normal with age. MCI involves a noticeable, consistent decline beyond what's typical—if you or family are concerned, ask a doctor about a cognitive screening.
Sources reviewed: 2026-10-25
References
- Petersen, R. C., et al. (1999). Mild cognitive impairment: clinical characterization and outcome. Archives of Neurology, 56(3), 303–308.
- Petersen, R. C., et al. (2018). Practice guideline update summary: Mild cognitive impairment. Neurology, 90(3), 126–135.
- Nasreddine, Z. S., et al. (2005). The Montreal Cognitive Assessment, MoCA. Journal of the American Geriatrics Society, 53(4), 695–699.