Background: Craniofacial abnormalities and increased pharyngeal collapsibility due to abnormal connective tissue suggest the possibility of an increased prevalence of obstructive sleep apnoea (OSA) in patients with Marfan's syndrome, but the actual prevalence is uncertain. Aortic dilatation and dissection are life-threatening manifestations of Marfan's syndrome and case reports have suggested a possible association with OSA, but data from cohort studies are not available.
Methods: A sleep study was performed in 61 patients with Ghent-criteria positive Marfan's syndrome (mean age±SD, 38.3±12.9, 37 females) and in 26 control subjects matched for age, gender, height and weight. OSA was defined using two conventional levels of apnoea/hypopnoea index (AHI), >5 and >15 per hour. In patients with Marfan's syndrome aortic root diameter was measured by echocardiography.
Results: More patients with Marfan's syndrome than controls had OSA (AHI >5, 32.8% compared to 11.5%, mean difference +21.3%, 95% CI 4.2-38.3%, p=0.04, AHI >15, 18.0% compared to 0%, mean difference +18.0%, 95% CI 8.4-27.7%, p=0.02). AHI was correlated with aortic root diameter (r=0.50, 95% CI 0.26-0.69, p=0.0003), and mean±SD aortic root diameter was significantly greater in patients with OSA (4.5±0.6cm) compared to those without OSA (3.7±0.6cm) (mean difference 0.8cm, 95% CI 0.4-1.2 cm, p<0.0001).
Conclusions: In patients with Marfan's syndrome the prevalence of OSA is considerably higher than in matched control subjects. OSA may be a risk factor for aortic root dilatation in Marfan's syndrome.