Analysis of sleep characteristics in post-polio syndrome patients

The main post-polio syndrome (PPS) symptoms are new weakness, new atrophy, fatigue, pain and sleep disturbances. Polysomnography is the gold standard for sleep analysis. Objective: To analyze sleep patterns in PPS patients. Method: Sixty patients (mean age 46.8 +/- 11.3 years) at the Federal University of Sao Paulo (UNIFESP/EPM) complaining of sleep disturbances were evaluated by means of polysomnography, performed at the Sleep Institute. Results: Sleep efficiency was lower due to high sleep latency and arousal index. The apnea and hypopnea index (AHI) and the periodic limb movements (PLM) index were higher. Sleep architecture was also impaired. There were no abnormalities of oxygen saturation, carbon dioxide levels, respiratory rate or heart rate. Conclusion: New post-polio sleep disturbances were isolated symptoms. It appears that these symptoms were not due to post-polio features, but rather, that they were due to dysfunction of the surviving motor neurons in the brainstem. Abnormal dopamine production, which is responsible for many sleep-related breathing disorders and abnormal movements, may also have been implicated in the present findings.