FOUR in five people with multiple sclerosis (MS) are misdiagnosed, with one in four told they have a trapped nerve, a charity has warned.

A survey by the MS Society found 81 per cent of sufferers had been given different explanations for their symptoms - including depression and stress - before MS was identified.

Almost 40 per cent had to wait a year before they discovered what was really wrong with them.

The charity acknowledged that the condition - which is particularly prevalent in Scotland, affecting more than 11,000 people - can be difficult to identify. However, they also warned delays starting treatment can be damaging for sufferers. Evidence has shown that early treatment has long-term benefits.

Michelle Mitchell, chief executive at the MS Society, said: "Our findings highlight the struggle people go through for years before they get an MS diagnosis.

"Being misdiagnosed or experiencing symptoms that can't be explained can put a considerable strain on people's emotions and health.

"A fast, accurate diagnosis enables people to take steps to begin to manage their condition, access treatment and take greater control of their lives again."

Across the UK 5,000 new cases of MS are diagnosed every year. In Scotland the charity has revealed for the first time that almost 700 people are told they have MS each year - reflecting higher rates of the illness north of the Border.

Claire Conlon, a 29-year-old teacher from Glasgow, said it took three years for her to be diagnosed with MS. The GP initially put the pain in her left knee down to her fitness workout.

Ms Conlon said: "My GP thought I'd pulled something at the gym so he gave me some exercises to do. I told him that a strange sensation was appearing every so often around my ribcage and stomach, and he prescribed me tablets to settle what he thought was stomach acid."

With the pain in her knee increasing and other symptoms including more frequent trips to the bathroom and blurry vision, Ms Conlon said her family persuaded her to see her GP again and was ultimately referred to a neurologist.

She said: "I felt like a complete hypochondriac, but I knew deep down there was something seriously wrong. I'd been typing my symptoms into Google and aside from Googling myself into a coffin, all fingers pointed at MS."

While initially scared, Ms Conlon said she was relieved to have an explanation for her ailments and has found the treatment effective.

She said: "I chose to take a daily injection. A year and a half later, I have never looked back. My walking and balance have vastly improved so I can go back to gym classes and run 10ks, which I couldn't do before my diagnosis."

There is no cure for MS, which affects nerves in the brain and spinal cord, causing problems with muscle movement, balance and vision.

It is the most common disabling neurological condition in young adults, with symptoms usually starting in the 20s and 30s.

Its causes are complex and not completely understood, but typical early symptoms include numbness, tingling, limb weakness, lack of co-ordination, loss of sight, fatigue and bladder and bowel problems.

Of the 1,515 people questioned for the survey to mark World MS Day, the most common early symptoms were reported as being numbness and altered sensations in different parts of the body (53 per cent), sight problems (47 per cent) and difficulty with walking (41 per cent).

Ms Mitchell said: "It's important for GPs to recognise the warning signs and refer people promptly to a consultant neurologist who can then make an accurate diagnosis.

"Most people who experience MS-like symptoms won't have the condition but if you're concerned for any reason your GP should still be your first port of call."