Association of ten gastrointestinal and other medical conditions with positivity to faecal occult blood testing in routine screening: a large prospective study of women in England.

Emily He,Robert Steele,Roger Blanks,Valerie Beral,Robyn L Ward,Jane Green,Kirstin Pirie,Rupert Alison,Karen Canfell,Gillian Reeves,Julietta Patnick

doi:10.1093/ije/dyy271

Abstract

BackgroundIn 2006, the Bowel Cancer Screening Programme (BCSP) in England began offering biennial faecal occult blood testing (FOBt) at ages 60–69 years. Although FOBt is aimed at detecting colorectal neoplasms, other conditions can affect the result. In a large UK prospective study, we examined associations, both before and after screening, between FOBt positivity and 10 conditions that are often associated with gastrointestinal bleeding.MethodsBy electronically linking BCSP and Million Women Study records, we identified 604 495 women without previous colorectal cancer who participated in their first routine FOBt screening between 2006 and 2012. Regression models, using linked national hospital admission records, yielded adjusted relative risks (RRs) in FOBt-positive versus FOBt-negative women for colorectal cancer, adenoma, diverticular disease, inflammatory bowel disease, haemorrhoids, upper gastrointestinal cancer, oesophagitis, peptic ulcer, anaemia and other haematological disorders.ResultsRRs in FOBt-positive versus FOBt-negative women were 201.3 (95% CI 173.8–233.2) for colorectal cancer and 197.9 (95% CI 180.6–216.8) for adenoma within 12 months after screening and 3.49 (95% CI 2.31–5.26) and 4.88 (95% CI 3.80–6.26), respectively, 12–24 months after screening; P < 0.001 for all RRs. In the 12 months after screening, the RR for inflammatory bowel disease was 26.3 (95% CI 19.9–34.7), and ranged between 2 and 5 for the upper gastrointestinal or haematological disorders. The RRs of being diagnosed with any of the eight conditions other than colorectal neoplasms before screening, and in the 12–24 months after screening, were 1.81 (95% CI 1.81–2.01) and 1.92 (95% CI 1.66–2.13), respectively.ConclusionsWhereas FOBt positivity is associated with a substantially increased risk of colorectal neoplasms after screening, eight other gastrointestinal and haematological conditions are also associated with FOBt positivity, both before and after screening.

Highlights

In 2006, the Bowel Cancer Screening Programme (BCSP) in England began offering biennial faecal occult blood testing (FOBt) at ages 60–69 years
Whereas FOBt positivity is associated with a substantially increased risk of colorectal neoplasms after screening, eight other gastrointestinal and haematological conditions are associated with FOBt positivity, both before and after screening
About one in eight women who were FOBt-positive did not undertake follow-up investigations through services provided by the national Bowel Cancer Screening Programme, but many of them had pre-existing conditions associated with gastrointestinal bleeding and appear to have chosen to seek follow-up through other services where they were already under care

Summary

Introduction

In 2006, the Bowel Cancer Screening Programme (BCSP) in England began offering biennial faecal occult blood testing (FOBt) at ages 60–69 years. Colorectal cancer is the third most common cause of cancer deaths in the UK, and accounted for 12% of all new cancers in 2014.1 As colorectal cancers are prone to bleeding, the rationale for screening with faecal occult blood test (FOBt) is to detect blood originating from otherwise asymptomatic tumours, thereby enabling diagnosis at an early, potentially curable stage.[2,3,4,5] it is acknowledged that FOBt positivity can be affected by a range of conditions other than colorectal cancer,[6] no previous study has evaluated the associations of FOBt positivity with other gastrointestinal or haematological conditions in a population-based bowel cancer screening programme. The National Health Service (NHS) Bowel Cancer Screening Programme (BCSP) in England was launched in 2006 to provide biennial colorectal cancer screening using guaiac-based FOBt. In this report, we link FOBt results in the BCSP with information on cause-specific hospital admissions in the large prospective study of women’s health, the Million Women Study. We investigated associations between FOBt positivity and 10 prespecified conditions related to gastrointestinal bleeding

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Conclusion