The effect of continuous positive airway pressure therapy on the prevalence of masked hypertension in obstructive sleep apnea patients.

BACKGROUND AND AIM

Obstructive sleep apnea (OSA) is a common cause of secondary arterial hypertension. Masked hypertension (MH) is defined as normal office blood pressure and abnormal results in 24 h ambulatory blood pressure monitoring (ABPM). The aim of this study was to evaluate the effect of CPAP therapy on the prevalence of MH in patients with OSA.

METHODS

43 patients (40 men) were included, average age 54.2±10.5 years. All underwent sleep study (PG or PSG) with a diagnosis of OSA indicated for CPAP treatment, average apnea-hypopnea index (AHI) 60.6±23.6. Patients were treated with CPAP for one year. Ambulatory blood pressure monitoring was performed before and after one year of treatment.

RESULTS

Masked hypertension was initially present in 25 (58.1%) and in 26 (60.5%) patients after one year of CPAP therapy. However, there was a statistically significant improvement in BP for all evaluated intervals of ABPM with the exception of systolic pressure during the daytime.

CONCLUSIONS

Masked hypertension was very prevalent in these patients with OSA. The CPAP treatment for one year however had no affect on prevalence of masked hypertension although there was a positive effect of CPAP treatment on blood pressure for all assessed intervals of ABPM with the exception of systolic BP during daytime.