Reorganization of sleep patterns in severe OSAS under prolonged CPAP treatment.

Objective: To evaluate the immediate and long-term recovery processes of sleep and daytime vigilance in patients with sleep apnea syndrome (OSAS) after continuous CPAP treatment.

Methods: Five consecutive polysomnographic (PSG) studies were carried out on 10 male patients with severe OSAS. The first recording (baseline) was accomplished without ventilatory support (N0).

Is insomnia a neurophysiological disorder? The role of sleep EEG microstructure.

Unlike other sleep disorders, such as sleep-related breathing disorders and periodic limb movement (PLM), the nature and severity of which are quantified by specific respiratory and motor indexes, no apparent organ dysfunction underlies several cases of insomnia (in particular primary insomnia), which can be objectively diagnosed only through the structural alterations of sleep. Polysomnography (PSG) investigation indicates that insomnia is the outcome of a neurophysiological disturbance that impairs the regulatory mechanisms of sleep control, including sleep duration, intensity, continuity and stability. In particular, analysis of sleep microstructure has permitted to establish that etiologic factors of different nature (including depressive disorders) exert a common destabilizing action on sleep, which is reflected in an increase of cyclic alternating pattern (CAP) rate.

CAP variables and arousals as sleep electroencephalogram markers for primary insomnia.

Objective: Polysomnographic (PSG) measures consistently reflect poor sleep quality and effective treatment in insomniac patients.

Methods: The PSG findings of 47 patients (18 M and 29 F, 42.5+/-10 years) meeting the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria for a diagnosis of primary insomnia were compared with those of 25 age- and gender-balanced healthy subjects (controls) without sleep complaints.