What is mild cognitive impairment (MCI)?
Mild cognitive impairment MCI Mild Cognitive Impairment (MCI) – is a condition in which there is a decline in memory or other thinking functions that the person himself or his family can notice, but without affecting daily independence. People with MCI continue to manage their lives, but sometimes feel slower, have difficulty remembering details, or have difficulty organizing themselves as they used to.
Causes of MCI
It is important to note that MCI does not represent a single disease, but rather a description of a degree of functional severity. There are many possible causes of this condition, some of which are reversible and treatable.
Among the possible reasons:
- Depression and anxiety states
- Sleep Disorders
- Vitamin deficiency
- Thyroid dysfunction
- Effect of medications
- Vascular diseases of the brain
- Degenerative diseases, including early stages of Alzheimer's disease.
What is the medical outlook (prognosis) when you have MCI?
In some people, MCI remains stable over time, in others it progresses, and in some it even regresses to normal functioning. Current data indicate that 10-15% of patients with MCI progress to dementia each year, but many others do not worsen at all. For this reason, it is important to complete the investigation and continue regular medical follow-up.
How do you diagnose MCI?
The diagnosis includes a medical interview, cognitive testing, daily functioning assessments, blood and imaging tests, and sometimes detailed neuropsychological tests. The goal of the investigation is to understand what is causing the cognitive decline and its severity, in order to identify reversible and treatable factors, and to assess whether it is an early stage of Alzheimer's disease, before significant functional decline is evident.
When Alzheimer's disease is suspected, it is possible, with the help of specialized tests - blood tests, cerebrospinal fluid (CSF) tests, or PET scans - to determine whether the decline is related to the accumulation of amyloid protein, a key marker in Alzheimer's disease.
This distinction is particularly important, as in recent years, there have been specific treatments targeting amyloid, but they are only suitable for patients in the early stages of Alzheimer's disease - that is, people with cognitive decline at the severity level of MCI or mild dementia. Suitability for these treatments is assessed based on the severity of the cognitive decline, the biological evidence that the cognitive decline is due to Alzheimer's disease, and the absence of risk factors for treatment.
Summary
MCI is a functional condition that describes mild cognitive decline without impairment of functional independence. MCI can be caused by many factors, some reversible and some as a result of Alzheimer's disease. When there is suspicion of early stage Alzheimer's disease, it is possible – and desirable – to perform specific tests and assess suitability for new anti-amyloid therapies, which can slow the progression of brain pathology and functional decline.
The author of the article
Dr. Talia Nathan, Neurology Specialist, Senior Physician in the Cognitive Neurology Unit, Sourasky Ichilov Tel Aviv Medical Center
Sources
- Frisoni, Giovanni B., et al. New landscape of the diagnosis of Alzheimer's disease. The Lancet. 2025; 406(10510): 1389–1407.
- Alzheimer's Association. More Than Normal Aging: Understanding Mild Cognitive Impairment. Alzheimer's Disease Facts and Figures Special Report, 2022.