Abstract. Lower gastrointestinal (GI) bleeding can be caused by colorectal polyps or cancer. The aim of the present study was to identify blood test variables and medications that can predict lower GI bleeding, which would allow for appropriate colonoscopy. The medical records of patients who underwent colonoscopy from September 2014 to September 2015 were retrospectively analyzed. The selected patients included 278 men (mean age, 67.0±11.5 years) and 249 women (mean age, 69.6±12.0 years). The diagnosis, medications, and blood test variables were compared between patients with and without bleeding. Logistic regression analysis was performed to determine the factors associated with lower GI bleeding. The presence of colorectal polyp and cancer was associated with lower GI bleeding (P=0.0044) with an odds ratio of 6.71 (P=0.0148). No lower GI bleeding was observed in patients taking non-steroidal anti-inflammatory drugs (NSAIDs), corticosteroids, or anticoagulants. The C-reactive protein (CRP) levels were significantly higher in patients with lower GI bleeding (P=0.0227). The Hb levels were lower in patients with lower GI bleeding, however this finding was not statistically significant (P>0.05). No blood test variable was associated with lower GI bleeding. Elevated CRP was associated with lower GI bleeding, while there was no association between the medications and lower GI bleeding.
IntroductionLower gastrointestinal (GI) bleeding occurs if the bleeding source is located distally to the Treitz ligament (1). It can be caused by colorectal polyps, colorectal cancer (CRC), or colonic diverticulum (2) and can be lethal in some patients, particularly the elderly (3). It is diagnosed and treated with colonoscopy (4,5).Lower GI bleeding is usually chronic and stops spontaneously (6). The identification of the bleeding site is important in its management (7). Lower GI bleeding is usually diagnosed with screening colonoscopy. If the risk factors are known, it is be possible to perform colonoscopy for such patients. The risk factors of patients hospitalized for severe lower GI bleeding include medication with non-steroidal anti-inflammatory drugs (NSAIDs) and anticoagulants (8). It is not clear whether NSAIDs and anticoagulants are related to lower GI bleeding diagnosed using screening colonoscopy. Corticosteroids, used in the treatment of autoimmune disease such as rheumatoid arthritis (9), are associated with bleeding from peptic ulcer (1). However, whether corticosteroids are associated with lower GI bleeding remains to be determined.Blood test variables are easy to obtain and quantitate. These variables can be useful in distinguishing upper from lower GI bleeding, which can aid the clinical diagnosis (10).In this study, we analyzed the diagnosis of screening colonoscopy and compared medication intake (i.e., NSAIDs, corticosteroids, and anticoagulants) between patients with or without lower GI bleeding. Blood test variables were also analyzed.
Materials and methodsEthics statement. The National Hospital Organization Shi...