Osteomalacia in institutionalized epileptic patients on long-term anticonvulsant therapy

Abstract
The occurrence of anticonvulsant osteomalacia was studied in 31 epileptic inpatients, 16 women and 15 men. Disturbances in biochemical parameters indicating osteomalacia were frequent. Of the patients, 32% were hypocalcemic, 55% had an increase in S-ALP [serum alkaline phosphatase] and 26% in U-HOP [urinary hydroxyproline] and dU-Ca [diurnal urinary Ca] was decreased in 55%. S-25OHD3 [serum 25-hydroxycholecalciferol] concentrations were significantly lower in patients compared with healthy controls. BMD [bone mineral density] was decreased in females compared with controls. Histomorphometric analysis revealed an increased amount of osteoid but the amount of trabecular bone was no lower than in controls. The amount of resorption surfaces increased in females. The patients who took less physical activity had a pronounced decrease in BMD. Osteomalacia was a frequent complication of long-term anticonvulsant medication, especially among institutionalized patients.