Study objectives: Patients with Fabry disease (FD) report impaired quality of life and excessive daytime sleepiness. Obstructive sleep apnea (OSA) is frequently reported among patients with FD; however, its prevalence and its influence on quality of life and daytime sleepiness in this population are unclear.
Methods: Patients with FD in a cohort from the University Hospital Zurich (n = 52) were one-to-two matched to healthy adult controls (n = 104) according to age, sex, and body mass index. Participants underwent structured interviews (including Short Form-36) and level-3 respiratory polygraphy. An apnea-hypopnea index of ≥ 5/h was defined as OSA and the severity of FD was quantified with the Mainz Severity Score Index (MSSI). Conditional logistic regression was used to compare the outcomes.
Results: In patients with FD the mean MSSI was 13.3 ± 10.5 points and OSA prevalence was 19.2% vs. 9.0% in the matched control group (p = 0.09). The apnea-hypopnea index was significantly higher in patients with FD than in the control group (0.5/h [0.2-3.0] vs. 0.2/h [0.1-1.8], p = 0.026). OSA severity was associated with impaired quality of life in four dimensions for the whole study population. Furthermore, patients with FD did report significantly higher daytime sleepiness (Epworth Sleepiness Scale 7.6 points vs. 6.3 points; p = 0.01) than healthy controls.
Conclusion: Patients with mild FD do not have a higher OSA prevalence than matched control subjects. Differences in OSA severity did not reach clinical significance. Further studies are warranted to determine the impact of OSA in patients with moderate-to-severe FD.
Keywords: Epidemiology; Fabry disease; Obstructive sleep apnea; Quality of life.