Transient insomnia induced by high-frequency deep brain stimulation in Parkinson disease

A 48-year-old woman presented with Parkinson disease (PD) in 1991. Disabling motor complications became evident in 1997. As the patient presented major levodopa-sensitive motor fluctuations in the absence of cognitive impairment, chronic bilateral subthalamic nucleus (STN) stimulation was proposed. Stereotaxic surgery was performed in April 2001. The subjective sleep quality was good for the week following surgery. One week after stereotaxic electrode placement, a Medtronic pulse generator (Minneapolis, MN) was implanted in the subclavicular region. After the generator had been turned on, the parkinsonian syndrome was significantly improved by STN stimulation, but the patient reported severe insomnia with 1 hour’s sleep per night. Surprisingly, this severe insomnia was well tolerated and was not associated with excessive daytime sleepiness or memory impairment. We investigated this phenomenon with polysomnography (table). Total sleep time (TST) during the first night (stimulation on) was 64 minutes. During the second night, STN stimulation was turned off: The …