Bone mineral status measured by direct photon absorptiometry in institutionalized adults receiving long-term anticonvulsant therapy and multivitamin supplementation.

The effects of long-term anticonvulsant drug therapy and multivitamin supplementation on bone mineral status were evaluated by direct photon absorptiometry in 53 adult residents of an institution for the mentally disturbed. Results demonstrated a similar amount of osteopenia for control subjects and those on anticonvulsant drugs. Average osteopenia was 8% for control subjects and 6% for subjects taking anticonvulsant drugs. Significant osteopenia was found in 25% of subjects taking anticonvulsant drugs and 20% of control subjects. Multivitamin supplementation had a beneficial effect on bone status in both subject groups. The use of anticonvulsant drugs had a significant effect on levels of alkaline phosphatase. Elevated alkaline phosphatase was found in 37% of subjects taking anticonvulsant drugs and 22% of control subjects. Hypocalcemia was found only in subjects taking anticonvulsant drugs (19%). Average calcium values were similar for both subject groups. Multivitamins were shown to have no significant effect on alkaline phosphatase or calcium values. Because both control subjects and those taking anticonvulsant drugs showed similar levels of osteopenia, factors other than anticonvulsant drug therapy appeared to adversely affect bone mineral status in this population. Conversely, multivitamin supplementation and the dietary control present in the institutionalized setting appear to have ameliorated the osteopenia commonly seen in anticonvulsant-treated populations without greatly modifying elevated alkaline phosphatase and hypocalcemia.