Randomized controlled trials (RCT) have shown that continuous positive airway pressure (CPAP) treatment of obstructive sleep apnea (OSA) reduces blood pressure (BP). CPAP treatment has never been compared to antihypertensive medications in a RCT. Design: This randomized controlled crossover trial assesses whether CPAP compared to valsartan produces a similar fall in BP in hypertensive OSA never treated for both conditions.
Twenty-five hypertensive patients (clinic systolic BP/diastolic BP: 154±15/103±12 mmHg) with OSA (age: 57±8 years, BMI: 28±5 kg/m2, AHI: 31±18/h) were treated for 8 weeks, randomized first to either CPAP or valsartan 160 mg. The second 8 weeks’ alternative treatment (cross-over) followed a 4-week washout period. BP was measured over 24-h, before and at the end of the two active treatment periods: mean 24-h BP was the primary outcome variable.
There was an overall significant difference in mean 24-h BP between the two treatments: the change in mean 24-h BP on CPAP was −2.4±3.9 mmHg (p<0.05), and −8.8±7.0 mmHg on valsartan (p<0.001), with a difference of −6.4 mmHg (95% confidence interval (CI) −10.7 to −2.1, p<0.01). The difference was significant not only during the daytime but also during nighttime: the change in nighttime 24-h BP on CPAP was −1.5±4.2 mmHg (NS), and −6.7±8.3 mmHg on valsartan (p<0.01), with a difference of −5.2 mmHg (p<0.05) (95% CI −10.2 to −0.2).
In a RCT, although fall in BP was significant under CPAP treatment, valsartan induced a three fold higher fall in mean 24-h BP than CPAP in hypertensive OSA patients.
This study suggests that most OSA patients may not be adequately treated regarding HT when using CPAP alone.
Jean-Louis Pepin, No Financial Disclosure Information; No Product/Research Disclosure Information