Author: Michael C. Wisotsky, PharmD, RPh
CD, Not UC, Linked to Regular Aspirin Use
In a large study whose results were published in the November 2011 issue of Alimentary Pharmacology & Therapeutics, researchers found that aspirin use can increase the risk of CD in adults, but not UC.
A total of 135,780 men and women aged 30 to 74 years were recruited in Europe. They completed a questionnaire at baseline detailing their regular aspirin use and were then followed up to identify those who developed either UC or CD. Each case was matched with 4 controls and odds ratios were calculated. The researchers found that regular aspirin intake was positively associated with the risk of developing CD (OR 6.14, 95% CI 1.76-21.35), but not UC (OR 1.29, 95% CI 0.67-2.46).
Scientists posit that the molecular reason for the link between aspirin and CD is due in part to aspirin’s inhibition of the synthesis of prostaglandins, thrombo-xanes, and prostacyclins, which are involved in the regulation of platelet aggregation, vasoconstriction, and dilation of vascular smooth muscle. Primarily, inhibition of prostaglandin H2, a potent anti-inflammatory prostaglandin, may lead to the development of IBD in adults. Further research is necessary to determine with certainty the mechanism of aspirin-induced IBD.
Longer Duration of NSAID Use Associated with CD
In a study presented at the American College of Gastroenterology 2011 Annual Scientific Meeting in Washington, DC, researchers demonstrated that high doses of nonsteroidal anti-inflammatory drugs (NSAIDs), longer duration of use, and greater frequency of use are all associated with an increased risk of CD and UC.
This finding seems to differ from aspirin’s effects, the researchers say. The prospective cohort study enrolled 76,814 women from a database that captured data on NSAID and aspirin use. CD or UC diagnosis was then confirmed. Cox proportional hazard models were used to examine relative risks for CD and UC after adjusting for variables. The study found that compared with nonusers, women who used NSAIDs for more than 15 days a month were at higher risk of developing CD or UC.
Although the study does demonstrate an increased risk of IBD among NSAID users, the authors warn that the results do not preclude the use of NSAIDs or aspirin in many patients, particularly patients seeking temporary pain relief or patients using low-dose aspirin for cardiovascular benefits.
Overprescription of Antibiotics Increases Risk of IBD
A new study shows that patients prescribed a large number of antibiotics may be at increased risk of developing inflammatory bowel disease (IBD), Crohn’s disease (CD), or ulcerative colitis (UC).
The study, published in the December 2011 issue of the American Journal of Gastroenterology, examined 2234 subjects diagnosed with IBD between 2001 and 2008 and matched them to 22,346 controls. Antibiotic data were recorded. The researchers found that dispensing of 3 or more prescriptions for antibiotics 2 years before study inclusion was associated with an increased risk of CD or UC (odds ratio [OR] 1.5, 95% confidence interval [CI] 1.3-18; P <.0001). They also showed that the association was nominally stronger in CD cases for ≥1 and ≥2 dispensations, while the association was stronger in UC cases for ≥3 dispensations.
Researchers warned that while the study does not necessarily implicate antibiotic use in IBD, it certainly demonstrates a clear link between IBD and intestinal bacteria. It provides more evidence that antibiotic use should be limited to cases where it is absolutely necessary.
Fast Fact: If a person has a relative with Crohn’s disease, his/ her risk of developing the disease is estimated to be at least 10 times that of the general population, and 30 times greater if the relative is a sibling.
About the Author
Michael C. Wisotsky, PharmD, RPh, practices in Shrewsbury, New Jersey.