The impact of diagnosis on health-related quality of life in people with coeliac disease: a UK population-based longitudinal perspective

BACKGROUND: Before diagnosis, people with coeliac disease suffer reduced quality of life, which improves substantially after the disease has been diagnosed. Delayed diagnosis is common. The aim of this study was to assess changes over time in prevalence of coeliac disease symptoms/associated medical conditions, time to diagnosis, quality of life and its determinants before and after diagnosis in the United Kingdom. METHODS: A postal questionnaire was designed in 2015 and sent to 4000 individuals with diagnosed coeliac disease, requesting information on respondents’ socio-demographic and clinical characteristics, and their quality of life pre- and post-diagnosis using the EQ-5D instrument. Data were analysed and compared with results from a survey conducted in 2006 using descriptive analyses, univariate and multivariable regression methods. RESULTS: The survey response rate was 40%. Sixty-five percent of respondents reported at least 4 symptoms pre-diagnosis, a significant reduction by 13 percentage points (95% CI: -16.9, − 9.4; p-value: < 0.001) compared to 2006. Pre-diagnosis mean duration of symptoms was 12.8 years (SD: 15.3), a non-significant reduction of 0.6 years (95% CI: -2, 0.8; p-value: 0.426) compared to 2006. There was a significant improvement of 0.20 (95% CI: 0.18, 0.22; p-value: < 0.001) in quality of life from pre- (0.65) to post-diagnosis (0.85). Pre-diagnosis values were significantly higher by 0.09 (95% CI: 0.06, 0.12; p-value: < 0.001) than in 2006. Number of symptoms and low income were associated with decreased quality of life. CONCLUSIONS: Undiagnosed coeliac disease is associated with a substantial decrement in quality of life. Time to diagnosis has not significantly shortened over the decade 2006–2015, but symptoms are less severe when diagnosis occurs. Harmonising clinical guidelines for intensified active case finding will help improve quality of life of people with coeliac disease. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12876-019-0980-6) contains supplementary material, which is available to authorized users.