This booklet covers information on what people may expect following a diagnosis of ME/CFS in terms of disability, improvement, recovery, and quality of life.

It is based on extensive evidence from people with ME/CFS, their partners or family members, a small number of research studies, and clinical opinion from doctors who are involved in the management of ME/CFS.

What to expect following a diagnosis of ME/CFS in terms of disability, improvement, recovery, and quality of life

Including:

• Prevalence
• Prognosis: Chance for improvement or recovery
• Fluctuation and symptom severity
• What factors can influence prognosis?
• Research into prognosis
• Quality of life
• Mental health
• Permanent ill-health
• Dr Charles' Shepherd professional opinion and story

Prevalence: How many people are affected by ME/CFS in the UK?

Based on the most recent research evidence from the University of Edinburgh (Samms and Ponting, 2025), around 402,000 adults and children in the UK have ME/CFS. This figure is likely to be even higher due to a significant number of the 2 million people with Long Covid, possibly around 50%, also meeting diagnostic criteria for ME/CFS.

This means that ME/CFS is not uncommon and has a higher prevalence than multiple sclerosis and several other serious long-term medical conditions. Yet it receives a disproportionately low amount of government funding for services and research.

There is no sound research evidence about the scale of illness severity. However, it is generally accepted that around 25% of people with ME/CFS (possibly as many as 100,000) are severely affected at some point, and perhaps around 2% (8,000) are bedbound and very severely affected and require a great deal of care and support.

Prognosis: What are the chances of improving or recovering from ME/CFS?

Prognosis is a forecast, based on patient and clinical experience, and research evidence, of the likely course of a medical condition. However, it is difficult to predict individual outcomes in a condition like ME/CFS that affects different people in different ways.

Overall, and taking into account the fluctuating nature of ME/CFS, most people with ME/CFS fall into one or more of the descriptions following.

Please note that some people follow a more complicated course and do not fit neatly into any one of these six basic descriptions. For example, some people make a significant degree of improvement, have a relapse, but then only make a partial improvement. And some people who return to normal health, or almost normal health, then find that their ME/CFS recurs after an infection.

Recovery

This refers to a return to full and sustained normal health, or near normal health. Unfortunately, the percentage of adults who make a full recovery from ME/CFS appears to be only around 5% and probably no more than 10%. In some cases, where recovery has occurred in less than a year from symptom onset, a more appropriate diagnosis may have been a self-limiting post-viral fatigue syndrome. The situation for children and young people is generally considered to be significantly better than for adults (references: Bell and Rowe).

Significant improvement

A gradual overall improvement in functional ability and symptom severity, which tends to occur within the first few years. This group often then reach a ‘glass ceiling’ from which there is no further improvement. For others, the process may take much longer.

Partial improvement

Some degree of improvement, which again is followed by stabilisation but at a much lower level of physical and mental capability compared to before the development of ME/CFS.

No improvement

A failure to make any improvement following the acute or post-infectious phase of their illness.

Severe and very severe ME/CFS

Estimated to affect around 25% of people at some point in their illness. Some people are severely affected at the onset of their illness. In others this follows a slower deterioration in health.

Progressive deterioration

Although a progressive deterioration is not the norm this does sometimes happen. Where any form of progressive deterioration occurs, a detailed medical re-assessment is essential to rule out other possible causes, especially conditions like hypothyroidism, that can cause ME/CFS-like symptoms.

Fluctuation and symptom severity

As already noted, most people with ME/CFS find that their illness fluctuates over the course of days, weeks, months, and years. Symptoms fluctuate in both severity and range, as does the level of discomfort and disability they bring. ME/CFS can be very unpredictable.

More significant exacerbations or relapses are often precipitated by:

• Frequent episodes of post-exertional malaise (PEM) – the characteristic symptom of ME/CFS
• Infections, operations, temperature extremes, stressful life events and sometimes vaccinations

For some, the severity of symptoms and the reduction in functional ability is more progressive and their overall health deteriorates over time. We don’t know why this happens; it remains one of the many unanswered questions about the condition.

• The MEA has published an information leaflet covering exacerbations and relapses. Relapses, Exacerbations and Flare-ups can be downloaded free here: https://meassociation.org.uk/42mz
• The MEA Disability Rating Scale can be used if you need to describe in percentage terms the effect ME/CFS is having on your ability to care for yourself and your level of mobility, as well as monitoring progress. https://meassociation.org.uk/f7fq

What factors are believed to influence prognosis?

Very little is currently known about the reasons for variations in prognosis. However, evidence from people with ME/CFS, their clinicians, and the limited amount of published research in this area indicates that a number of factors appear to influence both severity and outcome in ME/CFS.

Factors which may indicate a better prognosis:

• Early diagnosis with appropriate identification and management of any other factors – physical, psychological and/or social – which may be relevant.
• An acute-onset illness, often post-viral, particularly when this occurs in the presence of an uncomplicated psychological background.
• Onset in older age (Ghali et al, 2022).

The MEA website section called Medical Matters covers ageing and ME/CFS in more detail: https://meassociation.org.uk/7k4c

Factors which may indicate a less favourable prognosis:

• Diagnostic delay, especially when this is accompanied by no management or bad management during the very early stages of ME/ CFS.
• Onset of symptoms following a severe infective illness or without any clear precipitating event.
• Background of adverse psychological and social factors.
• Co-existence of other chronic medical conditions.
• Management which has involved inappropriate guidance on activity and energy management or failed to recognise symptoms which may be treatable to some extent.
• Presence of severe, unremitting, and often multiple symptoms.

Those who are severely or very severely affected, and remain in a bedbound state for long periods of time, are believed to have the worst prognosis.

Research into prognosis

Several research studies indicate that the scale of impairment across a wide range of physical and mental activities can be just as great, or greater, than is seen in many other chronic medical conditions. This includes kidney and heart disease, multiple sclerosis, and cancer – all of which is likely to have an adverse effect on the outcome or prognosis in any individual case.

Research into prognosis also indicates that ME/CFS often becomes a chronic and very disabling illness with complete and sustained recovery only occurring in a small minority of cases.

A systematic review of 14 studies (Cairns and Hotopf, 2005) found a median full recovery rate during follow-up periods of 5%. The median proportion of patients who improved during follow-up was 39.5%.

The section on Prognosis in the 2002 ME/CFS Working Group Report to the Chief Medical Officer, which examined all the evidence at the time, concluded:

“Prognosis is extremely variable. Although many patients have a fluctuating course with some setbacks, most will improve to some degree.

“However, health and functioning rarely return completely to the individual’s previous healthy levels; most of those who feel recovered stabilise at a lower level of functioning than before the illness…

“Overall, there is wide variation in the duration of illness with some people recovering in less than two years while others remain ill after several decades.

“Those who have been affected for several years seem less likely to recover; full recovery after symptoms persist for more than five years is rare”.

Quality of life in people with ME/CFS and those who care for them

Quality of Life is the medical term that describes how an illness affects all aspects of a person’s life.

Research studies that have examined quality-of-life measures in people with ME/CFS confirm that the scale of impairment across a range of physical and mental activities can be just as great or greater than in many other chronic medical conditions.

The study from Luis Nacul et al (2011) and the ME Biobank reported that:

“ME is as disabling and has a greater impact on functional status and wellbeing than other chronic diseases such as cancer. The emotional burden of ME is felt by lay carers as well as by people with ME.”

Another study on quality of life (Kingdon et al, 2018), used anonymised clinical data from people with ME/CFS and multiple sclerosis who had donated blood samples to the ME Biobank.

They reported that people with ME/CFS were measurably more disabled than people with multiple sclerosis and healthy controls. They also worked fewer hours and had lower incomes compared to people in the other two groups.

Two of the more recent studies on prognosis come from Dr Nina Muirhead and colleagues who looked at quality of life in people with ME/CFS (Muirhead et al, 2024) and in those who are partners or family members of people with ME/CFS (Vyas et al, 2022).

The first study analysed data from 876 people with ME/CFS in 26 countries and confirmed previous reports relating to significant reductions in quality of life. They concluded that: contrary to popular misconception, anxiety and depression are the least often affected areas in people with ME/CFS who are most impacted by their inability to perform usual activities.

The second study, which involved 1,418 partners or family members from 30 countries concluded:

Family members were most impacted emotionally by worry, frustration and sadness, and personally by family activities, holidays, sex life and finances.

The high level of physical disability associated with ME/CFS often stems from a combination of symptoms such as fatigue, pain, orthostatic intolerance, sleep disturbance, cognitive impairment and, in some cases, depression. This is further hampered by activity-induced muscle fatigue and post-exertional malaise (PEM) which can make the pursuit of increased activity extremely difficult.

However, as indicated above, some people find over time, and with careful management and support, symptoms become less severe, and improvements can be made in terms of functional ability.

While a complete recovery to previous levels of health is unlikely for most adults – and may be hampered by other factors such as age and co-morbidities – improvements to moderate and milder illness severities do occur, allowing for improvements in quality of life.

Quality of life – Mental Health

Accepting ME/CFS and often having to make major adjustments to a previously enjoyed lifestyle can be extremely difficult to achieve.

So in the first few years after diagnosis, drastic and unwelcome changes to lifestyle, work, relationships and friendships can lead to the added burden of mental health problems.

It can also be extremely demoralising to encounter a relapse when improvements have been made. And just living with any form of debilitating chronic illness can impact a person’s mental health.

It is important to seek medical help for mental health problems related to coping and adapting to a life with ME/CFS.

Being snatched from a previously active and healthy life – that might have included a comfortable level of financial security – is not something most people are prepared for, and issues that affect your mental health will lessen your overall quality of life.

Permanent Ill-Health

In the absence of high-quality research evidence on long-term prognosis, it is very difficult to provide accurate, individual assessments on longer-term outcomes. And, while there have been studies published that examine prognosis, some of these have an inherent selection bias, as they are often based on more severe cases and in hospital environments.

So there is an urgent need to carry out what are called longitudinal studies that track the progress of people with all degrees of severity over long periods of time for at least 10 years.

In relation to situations such as an application for retirement on the grounds of permanent ill-health, where an estimate has to be made on prognosis and permanency, conclusions are largely based on a combination of subjective clinical opinion and the very limited research evidence on long-term prognosis.

Overall, as already noted, there is a wide variation in both severity and duration of illness. Some people will have some degree of improvement over a period of time, although this is often years rather than months.

However, their health and functioning rarely returns to a previous level of health, and most people who improve tend to stabilise at a much lower level of functional ability than before the start of their illness.

In relation to forecasting permanency, research evidence indicates that the chances of returning to full normal health are very small, especially after being ill for four years or more. Most people will pursue a fluctuating course with periods of better health coupled with exacerbations and relapses. A significant minority will become severely and permanently disabled. Some will have a progressive deterioration in health.

The above observations all demonstrate how difficult it is to make a judgement on the likelihood of permanent ill-health in someone with ME/CFS.

PROFESSIONAL OPINION: Dr Charles Shepherd

Dr Charles Shepherd,
Trustee and Hon. Medical Adviser to the ME Association,
Member of the 2018-2021 NICE guideline on ME/CFS committee,
Member of the 2002 Chief Medical Officer's Working Group on ME/CFS

My own view, which is shared by many of my medical colleagues, is that it is almost impossible to make any reliable prediction of prognosis during the first two years of an ME/CFS diagnosis.

During years three and four, this type of assessment becomes more realistic – especially in people who have participated in all appropriate forms of management but have found that their condition has plateaued at a level of ability below that which is expected of a healthy person.

Where ME/CFS has persisted for four years or more with good management but without any significant improvement, and the overall level of ill health and disability has stabilised, ME/CFS becomes far more likely to be permanent. However, it may still follow a fluctuating course with relatively good and bad periods of health.

Reference: Medical Matters Q and A on permanency and retirement on the grounds of permanent ill health: https://meassociation.org.uk/qxq2