Prevention of Bone Loss and Vertebral Fractures in Patients with Chronic Epilepsy

In the early view issue of the journal Epilepsia, Drs. Lazzari and colleagues evaluated whether the use of a bisphosphonate or risedronate in addition to calcium and vitamin D in male veterans with epilepsy who were taking antiepileptic drugs over a long-term basis could prevent the loss of bone mass or bone mineral density associated with antiepileptic drug use. The study compared this treatment to patients who were treated with a placebo plus calcium and vitamin D. Antiepileptic drug and osteoporosis prevention trial (ADOPT) was designed as a prospective two-year, double-blind randomized placebo-control study involving 80 male veterans with epilepsy who were being treated with antiepileptic drugs such as phenytoin, phenobarbital, sodium valproate or carbamazepine for a minimum of two years. All enrolled participants received calcium and vitamin D supplementation and were randomized to risedronate or a matching placebo.

• 53 of 80 patients completed the study.
• In the placebo plus calcium and vitamin D group, there was a significant improvement in bone mineral density at any of the evaluated sites when compared to their baseline scans in 69% of the participants.
• In the risedronate plus calcium and vitamin D group, they also observed significant improvement of bone mineral density in 70% of the participants.
• At the end of the study, the risedronate group experienced a significant increase of bone mineral density at the lumbar spine, which was significantly larger than that seen in the placebo group.
• There were no differences between the groups regarding changes of total body bone mineral density or at the proximal bilateral femora.
• Five new vertebral fractures and one non-vertebral fracture were observed only in the placebo group.

The authors concluded:

• Calcium and vitamin D supplementation or calcium and vitamin D supplementation in addition to risedronate improved bone mineral density in more than 69% of male veterans with epilepsy who were taking antiepileptic drugs.
• In the group receiving risedronate plus calcium and vitamin D, there was a significant improvement of bone mineral density at the lumbar spine as compared to the placebo group which also received calcium and vitamin D.
• The use of risedronate plus calcium and vitamin D prevented the incidence of new vertebral fractures and one non-vertebral fracture in the cohort.