Long-term prognosis of clinical symptoms and health-related quality of life in microscopic colitis: a case-control study.

Background Microscopic colitis, comprising collagenous colitis (CC) and lymphocytic colitis (LC), is a common cause of chronic diarrhoea. The long-term prognosis is not well described. Aim To study outcome of symptoms and health-related quality of life (HRQoL). Methods A case-control study using a postal questionnaire with three population-based controls per patient matched for age, sex and municipality. HRQoL was assessed by the Short Health Scale (SHS). Patients in clinical remission, defined as a mean of <3 stools/day, were evaluated separately (CC; n=72, LC; n=60). Results The study included 212 patients and 627 matched controls. Median disease duration was 5.9 (range 0.5-27) years and 6.4 (0.3-14.8) years for CC and LC respectively. Abdominal pain, fatigue, arthralgia, myalgia, faecal incontinence and nocturnal defecation were significantly more prevalent in CC patients compared with controls. These differences persisted in CC patients in clinical remission with respect to abdominal pain (36% vs. 21%), fatigue (54% vs. 34%), arthralgia (61% vs. 41%) and myalgia (53% vs. 37%). In LC patients, abdominal pain, fatigue, faecal incontinence and nocturnal defecation were more prevalent compared with controls. In LC patients in clinical remission, fatigue was more prevalent compared with controls (54% vs. 37%). These differences were statistically significant (P<0.05). All four HRQoL dimensions (symptom burden, social function, disease-related worry, general well-being) were impaired in patients with active CC and LC. Conclusions Although considered to be in clinical remission, patients with microscopic colitis suffer from persisting symptoms such as abdominal pain, fatigue, arthralgia or myalgia several years after diagnosis.