Effect of sodium valproate on the sleep structures of epileptic patients

The aims of the present study were to investigate the effect of sodium valproate (VPA) on the sleep structures of epileptic patients and the correlation of these effects with patient weight gain. A total of 60 epileptic patients were divided into three groups: E-AED I (VPA administration for a duration of <3 months), E-AED II (VPA administration for a duration of >3 months) and ECO (without VPA) groups, for polysomnography monitoring. When the E-AED II group was compared with the E-AED I and ECO groups, non-rapid eye movement sleep phase 1 was significantly prolonged (92.10±48.24, 29.50±10.61 and 23.94±13.27 min, respectively; P<0.01), rapid eye movement sleep was significantly shortened (70.82±17.69, 116.99±12.90 and 126.19±35.01 min, respectively; P<0.01), sleep efficiency was significantly reduced (89.39±2.55, 91.98±2.53 and 91.96±3.14%, respectively; P<0.01), the number of times of that the patients awoke was significantly increased (7.25±2.86, 2.55±1.42 and 2.40±1.39, respectively; P<0.01) and the number of REM phases throughout the night was significantly reduced (P<0.01). There were no significant differences for the various sleep parameters between the E-AED I and ECO groups. Therefore, VPA is capable of inducing sleep structure disorders in epileptic patients. In addition, these disorders begin 3 months following the administration of VPA, which indicates that these disorders may be associated with VPA-induced weight gain.