Following up
Anti-epileptic drugs associated with an increased risk of fractures
Story by Laura Ly/Photo by Trudie Lee
A new study has shown that most anti-epileptic drugs are associated with an increased risk of non-traumatic fractures in patients 50 years of age or older. Although most commonly used to treat epilepsy, anti-epileptic drugs are also used to treat many other common conditions such as mental health disorders, headaches, and other chronic pain conditions.
The population-based study looked at almost 16,000 individuals who were taking anti-epileptic drugs and also suffered a non-traumatic fracture between 1996 and 2004. Non-traumatic fractures are fractures related to osteoporosis. Using factors such as age, sex, and ethnicity, the individuals were matched with more than 45,000 fracture-free individuals who acted as controls for the study.
“The study found that all the drugs—except for one, valproic acid—were associated with an increased risk of non-traumatic fractures in patients 50 years or older,” says Dr. Nathalie Jetté, one of the study’s researchers. Two important factors influenced the degree of fracture risk: the numbers and types of anti-epileptic drugs patients were taking. Certain drugs, such as phenytoin and carbamazepine—two of the most common drugs for epilepsy—were almost twice as likely to be associated with non-traumatic fractures. Also, patients taking more than one anti-epileptic drug were three times more likely to suffer fractures when compared to patients taking only one drug.
However, Dr. Jetté emphasizes that patients on anti-epileptic drugs can offset these effects by optimizing their bone health. Lifestyle changes, such as weight-bearing exercise, smoking cessation, and a diet rich in vitamin D and calcium, help prevent bone loss as we age. The same lifestyle factors have also shown to reduce the effects of osteoporosis after onset.
“There are many potential explanations for this association. For example, certain anti-epileptic drugs may affect vitamin D metabolism or calcium absorption in the body. But we need more research to better understand exactly how these drugs affect bone health,” explains Dr. Jetté. She is currently looking to expand the reach of the study to see if there is a similar association between non-traumatic fractures and other drugs that are used to treat other neurological conditions.