LOS ANGELES — Children with treated epilepsy show significant osteopenia, placing them at high risk for pathological fractures, early results from an ongoing prospective study have shown.
The findings suggest that epilepsy and/or its treatment either induce accelerated bone loss or are primary determinants of failure to accrue normal bone mineral density, according to Dr. Marc K. Drezner, a professor of medicine at the University of Wisconsin, Madison.
While older patients with treated epilepsy have osteopenia and pathologic fractures at a significantly higher rate than the general population, controversy exists over whether the osteopathy results from epilepsy and its treatments or reflects age-dependent bone disease, Dr. Drezner said in a poster presentation at the annual meeting of the Child Neurology Society.
Dr. Drezner and his associates compared age-normalized total body bone mineral density (BMD) z scores of 8- to 18-year-old patients with treated epilepsy and healthy controls, excluding epilepsy patients who were non-ambulatory, had chronic diseases other than epilepsy, or were taking medications with known adverse bone effects.
The investigation included 34 treated epilepsy patients and 24 healthy controls (mean age 13) with comparable gender and weight distributions, calcium intake, and activity levels.
The mean BMD z scores were −0.31 for the epilepsy patients and 0.71 for the control group, a statistically significant difference, Dr. Drezner stated. Of the 34 epilepsy patients, 8 had BMD measures more than one standard deviation below normal, indicating osteopenia, while none of the healthy controls had osteopenic measures. Also, 8 of the control patients had BMD measures more than one standard deviation above normal, compared with only 5 of the epilepsy patients.
This study, which is still enrolling patients, is supported by a grant from GlaxoSmithKline.