Sleep Disturbance, Obstructive Sleep Apnoea and Abnormal Periodic Leg Movements: Very Common Problems in Fabry...

To assess the prevalence of sleep disorder(s) in males with Fabry disease and explore possible association with disease phenotype.

Fabry disease, an X-linked lysosomal storage disease caused by deficiency in α-galactosidase, results in intracellular accumulation of globotriaosylceramide. It causes organ dysfunction, most significantly affecting renal, cerebrovascular and cardiovascular systems. Respiratory involvement may include obstructive lung disease, reduced diffusing capacity and thickened soft and hard palates. Patients commonly develop small-fibre sensory peripheral neuropathy manifested by acroparaesthesia and pain crises. Combined with self-reported sleep disturbance and snoring, these features suggest an increased risk of sleep disorders.

In-laboratory polysomnography (PSG) studies and sleep inventory assessments, including Epworth Sleepiness Scale (ESS), were performed in a cohort of male Fabry patients. PSGs were reviewed by a sleep physician. Sleep-disordered breathing and periodic leg movements were targeted for analysis. Associations with renal, cardiovascular and cerebrovascular function were sought.

Twenty males underwent overnight PSG. Patient baseline characteristics included age 43.9 ± 10.7 years, BMI 24.3 ± 3.8 kg/m², neck circumference 39.7 ± 3.3 cm and ESS 9.8 ± 5.1 (7/20, abnormal ESS >10). Abnormal periodic leg movement index (PLMI) was present in 95% (mean frequency 42.4 ± 28.5/min) and sleep-disordered breathing in 50% patients. Periodic leg movements were associated with pain and depression but not with increased cortical arousal.

Sleep-disordered breathing and abnormal PLMI are highly prevalent in patients with FD. The presence of abnormal PLMI alone appears to have minimal impact on sleep disturbance, but is associated with depression and analgesic requirement.