Effect of antihypertensive agents on sleep apnea and ambulatory blood pressure in patients with hypertension: A randomized controlled trial.

BACKGROUND: Obstructive sleep apnea (OSA) and hypertension are common conditions that may be linked through sympathetic activation and water retention. We hypothesized that diuretics, which reduce the body water content, may be more effective than amlodipine, a blood pressure (BP)-lowering agent implicated with edema, in controlling OSA in patients with hypertension. We also aimed to compare the effects of these treatments on ambulatory blood pressure monitoring (ABPM). METHODS: In a randomized, double-blind clinical trial, we compared the effects of chlorthalidone/amiloride 25/5 mg with amlodipine 10 mg on OSA measured by portable sleep monitor and BP measured by ABPM. The study included participants older than 40 who had moderate OSA (10-40 apneas/hour of sleep) and BP within the systolic range of 140-159 mmHg or diastolic range of 90-99 mmHg. RESULTS: The individuals in the experimental groups were comparable in age, gender, and other relevant characteristics. Neither the combination of diuretics nor amlodipine alone reduced the AHI after 8 weeks of treatment (AHI 26.3 with diuretics and 25.0 with amlodipine. P = 0.713). Both treatments significantly lowered office, 24-h, and nighttime ABP, but the two groups had no significant difference. CONCLUSION: Chlorthalidone associated with amiloride and amlodipine are ineffective in decreasing the frequency of sleep apnea episodes in patients with moderate OSA and hypertension. Both treatments have comparable effects in lowering both office and ambulatory blood pressure. The notion that treatments could offer benefits for both OSA and hypertension remains to be demonstrated. TRIAL REGISTRATION CLINICALTRIALS. GOV IDENTIFIER: NCT01896661.

Effects of chlorthalidone plus amiloride compared with amlodipine on short-term blood pressure variability in individuals with hypertension and obstructive sleep apnea: a randomized controlled trial.

OBJECTIVE: To compare the effects of chlortalidone plus amiloride and amlodipine on blood pressure (BP) variability in patients with hypertension and obstructive sleep apnea syndrome (OSA). METHODS: A randomized, controlled, double-blind trial enrolled men and women aged 40 years or older with a diagnosis of OSA (apnea-hypopnea index 10-40 apneas/h of sleep) confirmed by overnight laboratory polysomnography and systolic BP 140-159 mmHg or diastolic BP 90-99 mmHg. Participants were randomized to receive chlortalidone 25 mg plus amiloride 5 mg daily or amlodipine 10 mg daily for 8 weeks. BP variability was calculated from 24-hour ambulatory BP monitoring at baseline and follow-up using the following indices: SD, coefficient of variation, average real variability (ARV), time-rate index, and variability independent of the mean (VIM). RESULTS: The study included 65 patients, with 33 assigned to the chlortalidone plus amiloride group and 32 to the amlodipine group. Participants in both groups had similar baseline characteristics. Short-term BP variability decreased within groups for SD and ARV indexes for 24-hour systolic BP and daytime systolic BP, but statistically significant time*group interactions were found for sleep systolic SD and VIM, with greater reduction in patients treated with amlodipine. CONCLUSION: In brief, our study has shown that the use of chlorthalidone in combination with amiloride and amlodipine produces comparable effects on short-term BP variability in patients with hypertension and OSA. Therefore, our findings suggest that BP variability may not be a significant factor when choosing between these medications for the treatment of hypertension and OSA.

Effects of Antihypertensive Treatment on Left and Right Ventricular Global Longitudinal Strain and Diastolic Parameters in Patients with Hypertension and Obstructive Sleep Apnea: Randomized Clinical Trial of Chlorthalidone plus Amiloride vs. Amlodipine.

Hypertension is highly prevalent in patients with obstructive sleep apnea (OSA), and fluid retention with its nighttime rostral distribution is one potential mechanism. We tested whether or not diuretics differ from amlodipine in their impact on echocardiographic parameters. Patients with moderate OSA and hypertension were randomized to receive diuretics (chlorthalidone plus amiloride) or amlodipine daily for 8 weeks. We compared their effects on left and right ventricular global longitudinal strain (LV-GLS and RV-GLS, respectively), on LV diastolic parameters, and on LV remodeling. In the 55 participants who had echocardiographic images feasible for strain analysis, all echocardiographic parameters were within normal ranges. After 8 weeks, the 24 h blood pressure (BP) reduction values were similar, while most echocardiographic metrics were kept unchanged, except for LV-GLS and LV mass. In conclusion, the use of diuretics or amlodipine had small and similar effects on echocardiographic parameters in patients with moderate OSA and hypertension, suggesting that they do not have important effects on mediating the interaction between OSA and hypertension.

Association between different measurements of blood pressure variability by ABP monitoring and ankle-brachial index.

BACKGROUND: Blood pressure (BP) variability has been associated with cardiovascular outcomes, but there is no consensus about the more effective method to measure it by ambulatory blood pressure monitoring (ABPM). We evaluated the association between three different methods to estimate BP variability by ABPM and the ankle brachial index (ABI). METHODS AND RESULTS: In a cross-sectional study of patients with hypertension, BP variability was estimated by the time rate index (the first derivative of SBP over time), standard deviation (SD) of 24-hour SBP; and coefficient of variability of 24-hour SBP. ABI was measured with a doppler probe. The sample included 425 patients with a mean age of 57 ± 12 years, being 69.2% women, 26.1% current smokers and 22.1% diabetics. Abnormal ABI (≤ 0.90 or ≥ 1.40) was present in 58 patients. The time rate index was 0.516 ± 0.146 mmHg/min in patients with abnormal ABI versus 0.476 ± 0.124 mmHg/min in patients with normal ABI (P = 0.007). In a logistic regression model the time rate index was associated with ABI, regardless of age (OR = 6.9, 95% CI = 1.1- 42.1; P = 0.04). In a multiple linear regression model, adjusting for age, SBP and diabetes, the time rate index was strongly associated with ABI (P < 0.01). None of the other indexes of BP variability were associated with ABI in univariate and multivariate analyses. CONCLUSION: Time rate index is a sensible method to measure BP variability by ABPM. Its performance for risk stratification of patients with hypertension should be explored in longitudinal studies.