A recent study evaluated whether antithrombotic medications increase the risk of hematuria, the presence of blood in the urine.
Antithrombotic medications, commonly known as blood thinners, are life-saving drugs used to prevent heart attacks and strokes by preventing the formation of blood clots. These include anticoagulant and antiplatelet medications. Unfortunately, these medications are associated with significant adverse events such as bleeding within the skull, stomach, or intestines. Since these drugs allow blood to flow easier throughout the cardiovascular system, it is very common to find blood in the urine. This is known as hematuria. It is unknown how common and how severe this finding can be in patients treated with antithrombotic medication. As of yet, no studies have examined hematuria-related complications.
Researchers at the Sunnybrook Health Sciences Centre’s Division of Urology in Toronto, Canada examined the rate of hematuria-related complications in over 800,000 elderly patients. These complications were defined as a visit to the emergency department, a hospitalization, or a urological procedure to investigate or manage hematuria over the course of 7.3 years. The results were recently published in the Journal of the American Medical Association.
Patients on Blood Thinners Had More Hematuria-Related Complications
The results showed that, when compared to non-users of blood thinners, patients on these medications showed a higher prevalence of hematuria-related complications. Urological procedures to manage hematuria were the most common complication reported, followed by hospitalizations, and emergency department visits. The highest association between antithrombotic use and hematuria-related complications was for emergency room visits and this rate was highest among patients over 85 years old.
Older Blood Thinners vs New Blood Thinners
The researchers also examined each blood thinner medication individually to evaluate the risk of hematuria-related complications. As a general trend, patients using older antithrombotic agents (aspirin or warfarin) experienced lower rates of hematuria-related complications, but these complications were more common with anticoagulants than with antiplatelets.
Of the newer oral anticoagulant medications, dabigatran (Pradaxa) was associated with the lowest rate of hematuria-related complications and rivaroxaban (Xarelto) was associated with the highest rate. Similarly, clopidogrel (Plavix), ticagrelor (Brilinta), and prasugrel (Effient) showed higher hematuria-related complication rates as compared with aspirin. Some patients require treatment with both antiplatelets and anticoagulants. These patients have an expected increased risk of hematuria-related complications as compared with patients using only one type of antithrombotic agent.
In conclusion, patients taking blood thinners are at an increased risk of hematuria-related complications. Patients are usually required to take antithrombotic medication for long periods of time, if not for life. Therefore, serious consideration of the risks and benefits of antithrombotic therapy is necessary as non-adherence is common and associated with an increased risk of stroke or heart attack.
Written by Jessica Caporuscio, PharmD
Reference: Wallis CJD, Juvet T, Lee Y, et al. Association Between Use of Antithrombotic Medication and Hematuria-Related Complications. JAMA. 2017