Lack of polysomnographic Non-REM sleep changes in early Parkinson's disease.

BACKGROUND: Polysomnography (PSG) data are rare in patients who have early stage idiopathic Parkinson's disease (IPD). METHODS: Thirty-three patients who had IPD with a disease duration </= 3 years and 37 age-matched controls were recruited. PSG analysis was performed on current medication. RESULTS: Patients with IPD had a reduced mean percentage of muscle atonia during rapid eye movement (REM) sleep (80% vs 93%; P < 0.05). Total sleep time, sleep efficiency, indices/hour of arousals, awakenings, apnea/hypopnea, and periodic leg movements were similar in both groups. Age, but not dopaminergic medication, had a negative impact on sleep architecture in patients with IPD. There was no correlation between sleep efficiency assessed by PSG and sleep quality assessed by questionnaire. CONCLUSIONS: The results confirmed a reduction in muscle atonia during REM sleep as a characteristic finding in early IPD. However, there were no further disease-inherent or medication-induced changes in sleep architecture. Although sleep disturbances are considered to be an integral part of IPD, PSG cannot yet identify them objectively at an early stage.