Gut: shock! Antibiotics actually increase the risk of colon cancer!

August 28, 2019 / biool / - according to a study published in the journal gut, the use of antibiotics (tablets / capsules) will increase the risk of colorectal cancer (colon cancer), but the risk of colorectal cancer is low, and to a certain extent depends on the type and type of drugs prescribed The researchers said the results showed a pattern of risk that may be related to differences in the activity of intestinal microbiota (bacteria) in the gut, a study that reaffirmed the importance of judicious use of drugs In 2010, patients around the world took an estimated 70 billion doses of antibiotics - the equivalent of 10 doses per person Antibiotics have a strong and lasting effect on intestinal microflora, changing the balance of beneficial and harmful bacteria The researchers want to know if and how this affects the risk of colorectal cancer They used data submitted to the national representative clinical practice research data link (cprd) between 1989 and 2012 Among them are the anonymous medical records of 11 million 300 thousand people, including 674 general practitioners, accounting for about 7% of the British population The researchers collected prescription information from 28930 patients (19726 of whom were diagnosed with colorectal cancer during an average 8-year monitoring period, 9254 of whom were diagnosed with colorectal cancer), and 137077 of whom matched their age and gender but did not develop the cancer Photo source: 70% (20278) of gut patients with colorectal cancer and rectal cancer used antibiotics, while only 68.5% (93862) of non colorectal and rectal cancer patients used antibiotics Nearly 60% of the study participants were prescribed more than one antibiotic Patients with colorectal cancer were more likely to take antibiotics: 71.5% versus 69% The exposure level of rectal cancer patients was equivalent (67%) The link between colorectal cancer and antibiotic use is evident in patients who took these drugs more than 10 years before cancer was diagnosed Compared with patients without cancer, patients with colorectal cancer are more likely to have been prescribed antibiotics for anaerobic bacteria that do not need oxygen, as well as antibiotics for anaerobic bacteria that need oxygen However, patients with rectal cancer are less likely to take antibiotics against aerobic bacteria Cancer sites are also related to the use of antibiotics Cancer in the proximal colon (the first and middle parts of the bowl) is associated with the use of antibiotics against anaerobes, compared with people without cancer But antibiotic use has nothing to do with distal colon cancer, which is the last part of the gut After considering the potential factors, such as overweight, smoking and moderate to severe drinking, the cumulative use of antibiotics in a relatively short period of time (more than 16 days) is related to the increased risk of colorectal cancer, of which the impact on proximal colon cancer is the largest The opposite is true for rectal cancer, where patients who took antibiotics for more than 60 days had a 15% lower risk of cancer than those who did not Penicillin was consistently associated with a high risk of proximal colon cancer when the analysis was limited to patients who had only one antibiotic and those who had not Ampicillin / amoxicillin is the most commonly used penicillin in these patients In contrast, the low risk of rectal cancer is related to the prescription of tetracycline This is an observational study, so the cause cannot be determined, and researchers cannot capture potential lifestyle factors for all participants, or hospital treatments that may affect overall cancer risk Nevertheless, their results show that there are "substantial" differences in the size and mode of action of antibiotics in different locations of the intestine, and they conclude that: "regardless of whether antibiotic exposure is the cause of colon cancer risk or the risk of colon cancer, our results emphasize the importance of rational use of antibiotics by clinicians "Reference: Jiajia Zhang et al, oral antibiotic use and risk of chromatic cancer in the United Kingdom, 1989-2012: a matched case control study, gut (2019) Doi: 10.1136/gutjnl-2019-318593