The incidence of late-onset Pompe disease in subjects with obstructive sleep apnea

Patients with obstructive sleep apnea/hypopnea (OSA) have, on average, a
narrower and more collapsible upper airway relative to others. They may
overcome the abnormal upper airway mechanics during wakefulness by increased
activation of upper airway dilators but develop OSA in sleep because of a
reduction in basal upper airway muscle activity and attenuation of the
mechanisms involved in activating upper airway dilators in response to negative
pressure. Patients with abnormal passive upper airway mechanics are more
dependent on upper airway muscle activation to maintain upper airway patency
and, hence, are more vulnerable to sleep-related changes in neuromuscular
control of pharyngeal muscles. Patients who have respiratory insufficiency
related to neuromuscular disease are at high risk for sleep apnea and nocturnal
hypoventilation, and these conditions often occur before the development of
daytime respiratory insufficiency. Early detection of respiratory insufficiency
is critical in the management of patients who have late-onset Pompe disease.
This is a slowly progressive muscle disorder based on acid maltase deficiency,
is a rare genetic lysosomal storage disorder caused by an absence or deficiency
of the lysosomal enzyme acid -glucosidase (GAA). Late-onset Pompe disease is
characterized by substantial involvement of skeletal muscle, which leads to
progressive muscle weakness and respiratory insufficiency. In late-onset Pompe
disease, death is usually due to respiratory complications.

The aim of this study is to estimate the prevalence of late-onset inherited
Pompe disease in a large cohort of patients with recently diagnosed obstructive
sleep apnea syndrome (OSAS) in two different centres across Europe.

This is a cross-sectional, explorative study to measure the prevalence of
late-onset Pompe disease in subjects with an established diagnosis of
obstructive sleep apnea syndrome. In two different study centers in Europe
(Leiden, Copenhagen) patients will be asked to donate a blood sample for the
detection of Acid -glucosidase enzyme activity. Patient information sheets will
be mailed to all patients known in an OSAS database of the clinic. The medical
record of each patient will be checked to know if the in- and exclusion
criteria of this study are met.

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