Prevalence of sleep apnea and cardiovascular risk factors in patients with hypertension in a day hospital model

Abstract

Introduction: To identify patients at risk for obstructive sleep apnea (OSA) syndrome at a specialized hypertension center, we administered questionnaires and used respiratory polygraphy (RP).

Results: We studied 168 patients (64.8% men and 35.2% women). Patients' body mass index (BMI) was 34.7 ± 6.79 and Epworth Sleepiness Scale (ESS) scores were 8.01 for male and 8.92 for women (p = 0.69). RP recordings revealed AHI (Apnea-Hypopnea Index) of 18.03 ± 15.7, an ODI (Oxygen Desaturation Index) of 18.6 ± 15.2, and a time oxygen saturation <90% (%) of 20.8 ± 24.3. Around 44% of patients had an AHI of >15 events/h, and continuous positive airway pressure (CPAP) was recommended to 69 patients (41.07%). Pulse wave velocity (PWV) showed high values in AHI > 15/h (p = 0.050), and carotid intima-media thickness (IMT) did not correlate with AHI > 15; right IMT: 0.83 ± 1.3 versus 0.78 ± 0.13 mm (p = 0.41) and 0.82 ± 0.16 versus 0.78 ± 0.19 mm (p = 0.40). However, we find correlation with carotid plaque (p = 0.046). The ACC/AHA calculator revealed a gradual increase in the risk of cardiovascular events: 8.7% with AHI < 5/h, and 30.3% in severe OSA.

Conclusions: In hypertension (HT) patients, RP revealed a high prevalence of OSA associated with carotid artery disease, high PWV, and increased cardiovascular risk.

Keywords: Hypertension; STOP–BANG; respiratory polygraphy; risk factor; sleep apnea.