Valproate for sleep consolidation in periodic limb movement disorder

In this study, open-label valproate (VPA) was administered to patients as a treatment for periodic limb movement disorder (PLMD). Six patients aged 28 to 62 years with complaints of sleep disturbance and at least five periodic limb movements (PLMs) per hour of sleep underwent polysomnograms (PSGs) with and without low-dose VPA treatment (125-600 mg at bedtime). After a baseline PSG, patients received VPA therapy from 2 weeks to 14 months, until the time of the follow-up PSG on VPA (median, 5 months; mean, 6 months). All six patients experienced subjective improvement in daytime alertness. Sleep efficiency was improved from 76% to 88% (p = 0.003), stage 1 (light) sleep decreased from 26% to 13% (p = 0.04), stage 3 and 4 (deep) sleep increased from 19% to 30% (p = 0.01), and rapid eye movement sleep was unchanged. There was a trend toward a reduction in the number of PLMs per hour of sleep and in the percentage of arousals associated with PLMs. All of the patients continued taking VPA after the PSGs were completed. One patient discontinued VPA 1 month after completion of the last PSG because of short-term side effects, and one patient stopped VPA 22 months after the last PSG because of weight gain. Thus, these data indicate that VPA has a long-term beneficial effect on sleep consolidation in patients with PLMD.