Abstracts

Patients with epilepsy have higher rates of osteopenia and osteoporosis. The increased fracture rate is believed to be seizure-related. Chronic antiepileptic use may contribute to fracture risk, through their effects on bone density[1]. Clinicians should understand the clinical implications of long term antiepileptic treatment. This study examined fracture rates in patients on specific epilepsy medications., A bone health survey of 31 questions asked about medication use, fractures, smoking and alcohol use, concomitant diseases, and preventive behaviors for osteoporosis. Consecutive patients with appointments at two Epilepsy centers completed the survey during their visit and existing DXA scan results were collected, when available, from patients to correlate responses to survey., 273 patients completed the survey, 117(43%) males, 155(57%) females, and 1 unknown. The majority of patients (59%) were Caucasian, 13% were African Americans, and 19% were Hispanic. The mean age was 41.9 (range 13 - 89 years). 71 patients (28%) reported a bone fracture. Of these, 26 (36%) were males and 45 (63%) were female and with a mean age of 47.5 years. Half of the women over 50 years old reported a fracture. 26(35%) patients with a fracture reported exposure to both phenytoin [PHT] and carbamazepine [CBZ]. 19(30%) patients on PHT, who reported never having been exposed to CBZ, reported a fracture. Five patients (28%) on valproate monotherapy reported a fracture. Seven (17%) patients on CBZ monotherapy reported a fracture. The number of patients with a fracture increased with duration of use of PHT. At less than 5 years exposure, about 15% of patients experienced a fracture. Forty-five percent of patients on PHT reporting a fracture had greater than 10 years exposure. This same increase was not seen in patients taking CBZ monotherapy. Four of ten patients on lamotrigine monotherapy reported a history of fracture. DEXA scans were available for 57 subjects. 61% were female and the average age was 55. 39% were male with an average age of 54. The prevalence of osteopenia [40% women, 52% men] and osteoporosis [30% women, 22% men] was higher in this group of patients on antiepileptics than in the general population, where 0.6% of women over the age of 50 have osteoporosis.[2], This study found a difference in fracture rate by epilepsy medication. Patients on CBZ were found to have the lowest fracture rate. Limited DEXA scan data indicate worse osteopenia and osteoporosis among patients on anticonvulsants than the general population. The increased fracture rate in epilepsy may be partly due to metabolic effects of anticonvulsants on bone mineral density.
[1] Persson HB, [italic]et al.[/italic] Epilepsia. 2002;43(7):768-72.
[2] Pack A, [italic]et al. [/italic]Epilepsy [amp] Behavior 2003:4:169-174.,