The role of compliance with PAP use on blood pressure in patients with obstructive sleep apnea: is longer use a key-factor?

Blood pressure control in hypertensive sleep apnoea patients of the European Sleep Apnea Database cohort - effects of positive airway pressure and antihypertensive medication

Aims

We analysed longitudinal blood pressure (BP) data from hypertensive obstructive sleep apnoea (OSA) patients in the European Sleep Apnea Database cohort. The study investigated the interaction between positive airway pressure (PAP)-induced BP change and antihypertensive treatment (AHT).

Methods and results

Hypertensive patients with AHT [monotherapy/dual therapy n = 1283/652, mean age 59.6 ± 10.7/60.6 ± 10.3 years, body mass index (BMI) 34.2 ± 6.5/34.8 ± 7.0 kg/m2, apnoea-hypopnoea index 46 ± 25/46 ± 24 n/h, proportion female 29/26%, respectively] started PAP treatment. Office BP at baseline and 2- to 36-month follow-up were assessed. The interaction between AHT drug classes and PAP on BP was quantified and the influences of age, gender, BMI, co-morbidities, BP at baseline, and study site were evaluated. Following PAP treatment (daily usage, 5.6 ± 1.6/5.7 ± 1.9 h/day), systolic BP was reduced by -3.9 ± 15.5/-2.8 ± 17.7 mmHg in mono/dual AHT and diastolic BP by -3.0 ± 9.8/-2.7 ± 10.8 mmHg, respectively, all P < 0.0001. Systolic and diastolic BP control was improved following PAP treatment (38/35% to 54/46% and 67/67% to 79/74%, mono/dual AHT, respectively). PAP treatment duration predicted a larger BP improvement in the monotherapy group. Intake of renin-angiotensin blockers [angiotensin converting enzyme inhibitor (ACEI)/angiotensin receptor blocker (ARB)] alone or in any AHT combination was associated with better BP control. The AHT-dependent BP improvement was independent of confounders.

Conclusion

In this pan-European OSA patient cohort, BP control improved following initiation of PAP. Longer PAP treatment duration, was associated with a favourable effect on BP. Our study suggests that ACEI/ARB, alone or in combination with other drug classes, provides a particularly strong reduction of BP and better BP control when combined with PAP in OSA.

Long-term effect of continuous positive airway pressure therapy on blood pressure in patients with obstructive sleep apnea

Obstructive sleep apnea (OSA) is a common cause of hypertension. Previous studies have demonstrated beneficial short-term effects of continuous positive airway pressure (CPAP) therapy on blood pressure. However, long-term antihypertensive effects of CPAP have not been properly verified. This study examined the longitudinal effect of CPAP therapy adherence on blood pressure among OSA patients. All patients diagnosed with OSA and undergoing subsequent CPAP therapy at a Kanagawa-area sleep clinic were clinically followed for 24 months to examine CPAP adherence, as well as longitudinal changes in blood pressure and body weight because it may become a confound factor for changes in blood pressure. The hours of CPAP usage were collected over the course of 30 nights prior to each follow-up visit (1st, 3rd, 6th, 12th, and 24th month). The relationship between CPAP adherence and blood pressure was analyzed using mixed-effect logistic regression models. A total of 918 OSA patients were enrolled in the study. We found a significant reduction in diastolic blood pressure among patients with good CPAP adherence during the 24-month follow-up period (β = − 0.13, p = 0.03), when compared to the group with poor CPAP adherence. No significant association was found between CPAP adherence and weight loss (β = − 0.02, p = 0.59). Long-term, good CPAP therapy adherence was associated with lower diastolic blood pressure without significant weight loss.

Role of rhinomanometry in the prediction of therapeutic positive airway pressure for obstructive sleep apnea

Background

This study was conducted to evaluate the relationship between nasal resistance in different posture and optimal positive airway pressure (PAP) level. Other potential factors were also assessed for possible influence on PAP pressure.

Methods

Forty- three patients diagnosed with obstructive sleep apnea (OSA) were prospectively recruited in this study. Nasal resistance was assessed by active anterior rhinomanometry in a seated position and then in a supine position at pressures of 75, 150, and 300 pascal. The factors correlating with PAP pressure were analyzed, including nasal resistance and patients’ clinical data.

Results

Univariate analysis revealed that PAP pressure was correlated to nasal resistance in the supine position at 75 and 150 pascal (SupineNR75 and SupineNR150) (P = 0.019 and P = 0.004 in Spearman’s correlation coefficient analysis), but not correlated to nasal resistance in the seated position at different pressures or in the supine position at 300 pascal. The multiple linear regression analysis revealed that both SupineNR150 and body mass index (BMI) significantly predicted PAP pressure (β = 0.308, p = 0.044; β = 0.727, p = 0.006). The final PAP pressure predictive model was:

PAP pressure = 0.29 BMI + 2.65 SupineNR150 + 2.11.

Conclusions

Nasal resistance in the supine position measured at 150 pascal may provide valuable information regarding optimal PAP pressure. Rhinomanometry should be included in the treatment algorithm of OSA patients when PAP therapy is considered.