Chronic Fatigue Syndrome (CFS) could be costing more than £102 million a year in lost earnings, according to a new study.

ME (myalgic encephalomyelitis) affects about 6,000 adults and children across Sussex.

More than 1,000 of these are virtually housebound and in need of care.

The new study shows the UK economy is not only affected by sufferers who cannot work because they are unable, but also by family members who have to reduce their working hours to care for relatives with ME.

Dr Esther Crawley, who is a medical advisor to the Sussex ME/CFS Society, has carried out one of the first investigations into factors associated with patients who can no longer work because of the severity of the illness.

The research was compiled with the help of a team of academics at Bristol University’s School of Social and Community Medicine and has been published in the journal BMC Health Services Research.

Part-funded by the charity Action for ME, the study examined data from 2,170 patients attending five specialist services to estimate loss of earnings as a consequence of ME.

This was then compared against the overall productivity costs to the UK’s economy.

Many ME sufferers try to continue work despite the symptoms of the condition.

Loss of physical capacity is the main reason they stop working.

Dr Crawley said: “Our findings are important because they show the long-term cost to society, which must be accounted for in estimates of the cost-effectiveness of ME or CFS interventions and service provision.

“In addition to this indirect cost to the UK economy, health resource use and welfare payments impose direct costs, and families must bear the costs of informal care, often reducing their own working hours.

“In young adults, disruption of education reduces productivity in later years. Above and beyond these financial costs, ME or CFS has a huge impact on quality of life.”

ME is classified by the World Health Organisation as a neurological disorder. Its cause is still unknown although it is unlikely to be one single thing.

Symptoms include profound physical and mental fatigue, muscle pain, mood changes, sleep disturbance, difficulty with concentration and short-term memory, gastric and eyesight problems.

The symptoms, which vary and fluctuate, can be exacerbated by over-exertion.

Colin Barton, chairman of the Sussex ME/CFS society, said: “There is an urgent need for more adequate NHS provision for those affected by this often life-ruining illness that is costing so much.