At least one in 1,000 people are thought to have microscopic colitis in the UK with 17,000 new cases being diagnosed each year. However the real number could be a lot higher because it is often underreported and misdiagnosed.
One study showed that one in three patients with the condition were initially incorrectly diagnosed with irritable bowel syndrome (IBS). It is also a growing disease and the number of patients diagnosed has been increasing over the past 20 years.
Research by Guts UK has found that women are 700% more likely than men to suffer with the condition than men. The charity is calling for more research to determine the reasons behind this gender disparity in the hope it will lead to prevention, faster diagnoses and developments in treatments.
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What is microscopic colitis?
Microscopic colitis is an inflammation of the large intestine (bowel) that causes persistent, frequent and watery diarrhoea (throughout the day and night), stomach pain, fatigue, faecal incontinence and weight loss. It is a leading cause of diarrhoea in older adults and it can have a devastating impact on a person's quality of life. Scientists estimate that around 67,200 people are living with microscopic colitis in the UK.
Guts UK said patients with the condition often find it difficult to manage jobs, socialise, travel and take part in family life because of the urgent nature of their symptoms and their need to be near to toilet facilities at all times. Coping with this often leaves sufferers feeling very isolated and can have a significant and detrimental effect on their mental wellbeing. Many people suffer for years with microscopic colitis but the correct diagnosis and treatment can make a huge and dramatic difference to a person's quality of life.
How is is diagnosed and what causes it?
Microscopic colitis is named because, unlike other inflammatory bowel diseases (IBD) like Crohn's or ulcerative colitis, it can't be diagnosed with a colonoscopy alone and a sample of tissue taken from the bowel must be examined under a microscope to identify the condition. However, once confirmed treatment with prescribed medicine (a steroid called budesonide) is available and has shown to be very effective and often life-changing.
The causes of microscopic colitis and the reason it affects women disproportionately are still unclear. As it is a relatively new disease (first described in 1976) it has led to a presumption that it is environmental as opposed to genetic factors that are responsible for its occurrence.
Prior studies have suggested that a range of medications including proton pump inhibitors (PPIs) - which are used to reduce stomach acid, nonsteroidal anti-inflammatory drugs such as ibuprofen, statins, antidepressants, aspirin, and beta blockers may be associated with the disease as well as cigarette smoking and a co-diagnosis of an auto-immune disease.
Despite this marked gender discrepancy, the literature on reproductive and hormonal factors is very limited. Some scientists have hypothesised that there is a link with microscopic colitis and the use of oral contraceptive pills and HRT but more research is needed for this to be conclusive.
'The symptoms of microscopic colitis are awful'
Julie, 42, was diagnosed with microscopic colitis in 2020 and has described her range of symptoms as "awful". She said: "I experienced crippling stomach pain, nausea as well as watery diarrhoea which lasted for several weeks and only stopped when I was diagnosed and began a treatment of steroids. It all had a massive impact on my mental health since this was during lockdown and I worried about what could be wrong.
"It's a very isolating condition and I can understand why it's called a hidden disability. It's been over a year since I was diagnosed and I'm still having flare-ups. I am constantly thinking about what I am eating and when I am out where the nearest facilities are - it's exhausting."
What do the experts say?
Julie Harrington, CEO of Guts UK, said: "Thousands of people across the country are quite literally housebound with symptoms of microscopic colitis and we now know that the rates are increasing and are likely to grow further as the population ages. Further research is desperately needed to identify risk factors and find out why women are far more likely to suffer from microscopic colitis so we can move to a place where prevention and faster diagnosis is possible. In the meantime, I hope that this year's Microscopic Colitis Awareness Week will raise awareness of this extremely difficult condition and that sufferers discover the simple treatments that can make a huge and dramatic difference to their quality of life."
Professor Shaji Sebastian, consultant gastroenterologist at Hull University Teaching Hospitals NHS Trust and Guts UK trustee added: "Scientists still don't fully understand what causes microscopic colitis and further research is clearly needed to determine what could be a combination of factors. What we do know is that the condition can be very debilitating but with the right tests it's also very treatable. Early diagnosis is crucial to prevent patients from suffering when they don't have to, so my main message this Microscopic Colitis Awareness Week is don't suffer in silence and seek help from your GP if you're experiencing symptoms."
