BACKGROUND: Although sleep disturbances are highly prevalent in patients with Parkinson's disease, sleep macroarchitecture metrics show only minor changes.

OBJECTIVE: To assess alterations of the cyclic alternating pattern (CAP) as a critical feature of sleep microarchitecture in patients with prodromal, recent, and established Parkinson's disease.

METHODS: We evaluated overnight polysomnography for classic sleep macroarchitecture and CAP metrics in 68 patients at various disease stages and compared results to 22 age- and sex-matched controls.

RESULTS: Already at the prodromal stage, patients showed a significantly reduced CAP rate as a central characteristic of sleep microarchitecture. Temporal characteristics of CAP showed a gradual change over disease stages and correlated with motor performance. In contrast, the sleep macroarchitecture metrics did not differ between groups.

CONCLUSION: Data suggest that alterations of sleep microarchitecture are an early and more sensitive characteristic of Parkinson's disease than changes in sleep macroarchitecture.