Actor Christina Applegate has revealed that she has been diagnosed with multiple sclerosis (MS).

The Emmy award-winning actress, who has starred in Dead to Me and Anchorman, shared the news with fans on Twitter.

"Hi friends. A few months ago I was diagnosed with MS," she wrote. "It’s been a strange journey. But I have been so supported by people that I know who also have this condition."

Around 9,000 in Ireland and 130,000 people in the UK have MS, a lifelong condition where the immune system attacks the nervous system, causing a wide range of symptoms.

Despite the wealth of information available about MS, it’s often misunderstood, which can be frustrating for someone who has been diagnosed.

Here are a few things to know about the condition and how it can impact daily life…

1. There are many different symptoms
MS affects the brain and spinal cord and so can cause a wide range of symptoms that vary from person to person. In some cases, it can cause serious disability, although in others it can occasionally be mild.

The main symptoms include fatigue, limb weakness, difficulty walking, pain, vision problems, numbness and tingling in the body, problems with balance and issues with controlling the bladder.

Symptoms may come and go, or they can gradually get worse over time, depending on the type of MS you have.

We need your consent to load this Instagram contentWe use Instagram to manage extra content that can set cookies on your device and collect data about your activity. Please review their details and accept them to load the content.Manage Preferences

2. It’s an autoimmune disease
The cells in our nervous system are covered in a protective fatty protein layer called the myelin sheath.

In MS, the immune system (which normally protects us from bugs and viruses) mistakenly attacks the nerve cells, damaging the protective sheath and triggering a process called demyelination.

Because of this process, MS disrupts the ‘messages’ travelling along nerve fibres to the brain, causing them to slow down, become distorted, or not get through at all.

We need your consent to load this Instagram contentWe use Instagram to manage extra content that can set cookies on your device and collect data about your activity. Please review their details and accept them to load the content.Manage Preferences

3. People are usually diagnosed young
MS is most commonly diagnosed in people in their 20s and 30s, and it’s the most common cause of disability in younger adults.

That said, it can develop at any age, and statistics show that it’s more common in women than men.

We need your consent to load this Instagram contentWe use Instagram to manage extra content that can set cookies on your device and collect data about your activity. Please review their details and accept them to load the content.Manage Preferences

4. Treatment has radically improved the outlook for people with MS
Although there is no cure for MS, advancements in treatment have meant that while living with the symptoms can be difficult, it is much more manageable in this day and age, and individuals have a better overall quality of life.

The NHS say that the average life expectancy for people with MS is around five to 10 years lower than average, but the gap appears to be getting smaller as therapies aiming to treat progressive MS continue to be researched.

MS Ireland has more advice, support and information for anyone who is affected by MS, or if you simply want to know more about the condition.