Association between faecal occult bleeding and medicines prescribed for chronic disease: a data linkage study.

Aims: The presence of detectable faecal haemoglobin (f-Hb) has been shown to be associated with all-cause mortality and with death from a number of chronic diseases not known to cause gastrointestinal blood loss. This effect is independent of taking medicines that increase the risk of bleeding. To further investigate the association of f-Hb with chronic disease, the relationship between f-Hb and prescription of medicines for a variety of conditions was studied.

Methods: All subjects (134 192) who participated in guaiac faecal occult blood test (gFOBT) screening in Tayside, Scotland, between March 2000 and March 2016, were studied in a cross-sectional manner by linking their gFOBT result (abnormal or normal) with prescribing data at the time of the test.

Results: The screening participants with an abnormal gFOBT result were more likely to have been being prescribed medicines for heart disease, hypertension, diabetes and depression than those with a normal test result. This association persisted after adjustment for sex, age and deprivation (OR 1.35 (95%CI 1.23 to 1.48), 1.39 (1.27 to 1.52), 1.35 (1.15 to 1.58), 1.36 (1.16 to 1.59), all p<0.0001, for the four medicine categories, respectively).

Conclusions: The results of this study confer further substantial weight to the concept that detectable f-Hb is associated with a range of common chronic conditions that have a systemic inflammatory component; we speculate that f-Hb might have potential in identifying individuals who are high risk of developing chronic conditions or are at an early stage of disease.