What is reversible mild cognitive impairment (MCI)?
11th August 2025
Written by Dr Laura Meader, Clinical Neuropsychologist
All names and other potentially identifying information has been changed to protect anonymity
Mild cognitive impairment (MCI), sometimes called Mild cognitive disorder (MCD), is a diagnostic term used to describe problems with memory or other aspects of cognition (thinking abilities), usually affecting people aged 60+. Crucially, MCI implies that a person’s cognition and day-to-day functioning are not affected significantly enough to suggest an underlying dementia. As such, MCI sits somewhere in between “normal ageing” and dementia.
Photo by Alex Ware on Unsplash
In clinical practice, our job is to find out whether a person’s reported cognitive difficulties are in fact normal for their age or whether they might represent MCI or indeed dementia. MCI can feel like a vague diagnosis in practice as it tells us little about the cause of the problem. For some people, MCI is found to have a treatable cause and improves; for some it remains stable over time, and for others it signals the start of a dementia. Predicting MCI progression in a clear, measurable way is difficult, as research outcomes have been quite mixed. This in part reflects the finding that many factors play a role in determining people’s chances of developing a dementia in future, including age, type of MCI (whether the cognitive difficulty is concerned with memory or another cognitive domain), and lifestyle factors*.
I will now outline a clinical example of a person with an MCI that was found to be due to a reversible, treatable cause, and who did not go on to develop dementia.
Jane
Jane was a 68-year-old retired secretary, who was forgetting recent conversations she had had with her husband, and kept losing her belongings around the home. She would make small mistakes with cooking such as forgetting an ingredient, but otherwise she functioned well at home and was driving without difficulty. Jane’s reports of her “memory lapses” and day-to-day functioning were consistent with those of her husband. These problems had been happening for around 12 months.
Cognitive assessment
The neuropsychological assessment included tests of cognitive function covering a range of domains. Jane had scored a little below her age-matched peers in the areas of attention and memory. Her scores in all other areas, including language abilities, visuospatial function (making sense of visually-presented information) and higher level executive functions (such as problem-solving and planning) were within the expected ranges for her age and educational background.
Formulation
A neuropsychological formulation takes into account information from a clinical interview, observations made by the clinician, and any cognitive testing results. The aim of such a formulation is to make sense of a person’s difficulties in the context of all available information that is relevant to understand what may be happening. There may be other important context as well, such as medical background and mood factors, and these are always considered as well. A neuropsychological formulation may give rise to a diagnosis, and sometimes it is more about making links between different aspects of a person’s presentation and their difficulties to best help them manage a problem.
In Jane’s case, the clinical interview with her and her husband revealed that she had been experiencing sleep disturbance for around the same length of time as they had both noticed her memory and attention difficulties. Exploring this further, Jane explained that she had long-standing hip and knee pain and was on the waiting list for a hip replacement. The pain had become worse in the last year, such that it was making it difficult for Jane to find a comfortable sleeping position. Her experience of poor sleep and living with chronic pain was also impacting her mood, such that she felt somewhat lower in mood and more anxious than was typical for her.
Clinical impression
Given that Jane’s cognitive difficulties as measured by the formal assessment tools were mild in nature and only affected two closely-related cognitive domains, a diagnosis of MCI was given. She and her husband had described some changes in day-to-day functioning, but these were also to a minimal degree and so could not be thought of as indicative of a dementia. Since Jane’s reported cognitive difficulties began around the same time as her sleep disturbance and associated difficulties, this was further evidence of these being a likely cause of her cognitive problems.
Recommendations and longer-term outcome
We recommended that Jane seek advice from her local Pain Clinic to help her manage her hip and knee pain while awaiting her hip replacement. Jane was given advice around good sleep hygiene, to ensure she was doing everything she could in the meantime to maximise her chances of better sleep. We suggested that Jane speak to her GP about interventions for managing low mood and anxiety, which may include medication and/or talking therapies.
Several months later, Jane found some improvement to her sleep after advice from the Pain Clinic as well as practicing a good sleep hygiene routine. She found a significant improvement in her sleep quality and her mood following the hip replacement. This had a clear impact on her cognition, such that she only rarely experienced lapses in attention and memory and her reported overall quality of life had improved.
*Factors influencing the chances of developing dementia represents a large area of research and practice in its own right and will be explored in a future blog post.
Recommended reading
The Alzheimer’s Society website contains a lot of useful information about MCI: Mild cognitive impairment (MCI) | Alzheimer’s Society
The Dementia UK website is another useful resource, with a downloadable factsheet on MCI: What is mild cognitive impairment? – Dementia UK
The Dementia Research Institute (DRI) website has a section on MCI, focusing on the research evidence, and contains other useful information about research into dementia more broadly: Mild cognitive impairment | UK DRI
ReMind UK is a research and treatment centre based in Bath, in North East Somerset. Their website contains information about volunteering to be part of upcoming research. Depending on the study, they frequently recruit people with MCI, dementia, as well as “healthy controls”: ReMind UK – We’re getting ahead of dementia