Underdiagnosis of obstructive sleep apnoea in peripheral arterial disease
Background: Obstructive sleep apnoea (OSA) has been interdependently related to the onset and progression of a large portion of atherosclerotic cardiovascular disorders. In due consideration of OSA-mediated endothelial dysfunction, its impact on peripheral artery disease (PAD) is conceivable, but undefined.
Objectives: To identify the prevalence of OSA in a lower extremity artery disease (LEAD) study population.
Methods: 91 patients receiving in- and outpatient treatment for LEAD were included in this prospectively conducted trial. Additionally to angiologic examination, all patients underwent nocturnal screening for sleep disordered breathing by use of SOMNOcheck micro® (SC micro) and – dependent on the hereby obtained results' severity – polysomnography.
Results: Patients were principally late middle-aged (69.3 ± 10.8years), male (71.4%) and slightly overweight (BMI = 26.8 ± 3.9 kg/m2). Overnight screening determined sleep apnoea prevalence of 78.0%, of whom 90.1% exhibited a predominantly obstructive genesis. Mean apnoea hypopnoea index (AHI) and oxygen desaturation index (ODI) averaged 11.8/h ± 13.4/h and 8.9/h ± 14.2/h, respectively. Percentage AHI portions accounted for 22.5% (AHI: < 5/h), 53.5% (AHI: 5< 15/h), 16.9% (AHI: 15< 30/h) and 7.1% (AHI: ≥30/h). Distributive examination of AHI within LEAD severity groups evinced significant association (p = 0.047). In case of at least moderate sleep apnoea (AHI ≥15/h), polysomnography was performed (n= 17, 18.7% of whole collective). Correlative analysis objectified significant correlation of values obtained by SC micro recording and polysomnography, manifesting diagnostic accuracy of screening results.
Conclusions: OSA exhibits important prevalence of 70.3% in LEAD patients with prior undiagnosed sleep disordered breathing, indicating major OSA unawareness in this cardiovascular cohort. However, the impact of OSA treatment on LEAD propagation remains to be determined.