Quality of sleep is profoundly affected in patients with hypercapnic respiratory failure and restrictive disorders, with a decrease in rapid eye movement (REM) and slow wave sleep, and an increase in sleep fragmentation. Assisted ventilation aims at improving blood gases, but may also have a favorable impact on sleep structure. The investigators reviewed polysomnographic and blood gas data obtained between 1987 and 2008 in 95 patients with restrictive pulmonary disorders, before and after implementing non-invasive ventilatory support.

Chart review of all patients with predominantly restrictive pulmonary disorders treated for respiratory failure by NIV at our institution between 1987 and 2008.

Data systematically recorded included pulmonary function tests, diurnal arterial blood gases, and polysomnography before and after implementation of nocturnal NIV.

Inclusion Criteria:

• Patients with restrictive pulmonary disorders (neuro-muscular diseases, chest wall disorders, sequellae of tuberculosis) leading to hypercapnic respiratory failure requiring non invasive ventilation (NIV), investigated according to clinical standards in our institution by polysomnography before and after implementation of NIV

Exclusion Criteria:

• Patients fulfilling inclusion criteria for whom diagnostic polysomnography and/or polysomnography under NIV were not performed

Patients with respiratory failure due to predominantly restrictive disorders submitted to NIV in preparation for long-term home ventilation and assessed between 1987 and 2008 at the Sleep laboratory.