Changes in sleepiness and 24-h blood pressure following 4 months of CPAP treatment are not mediated by ICAM-1

Obesity does not modify the effect of continuous positive airway pressure on insulin resistance in adults with obstructive sleep apnoea

This study found no evidence that obesity significantly modifies the effect of 4 months of CPAP treatment on HOMA-IR. Longer duration of CPAP treatment may be needed in order to reduce insulin resistance and determine whether obesity modifies the effect. https://bit.ly/3CtX7jZ.

Nocturnal blood pressure and nocturnal blood pressure fluctuations: the effect of short-term CPAP therapy and their association with the severity of obstructive sleep apnea

STUDY OBJECTIVES

We determined the relationship of cardiovascular risk factors, cardiovascular diseases, nocturnal blood pressure (NBP), and NBP fluctuations (NBPFs) with the severity of obstructive sleep apnea (OSA). We also investigated the effect of short-term continuous positive airway pressure therapy on NBP parameters.

METHODS

This retrospective study included 548 patients from our cardiac clinic with suspected OSA. Patients underwent polysomnography and continuous NBP measurement using the pulse transit time. According to their apnea-hypopnea index (AHI), patients were subclassified as controls (AHI < 5 events/h), mild (AHI 5 to < 15 events/h), moderate (AHI 15 to < 30 events/h), and severe OSA (AHI ≥ 30 events/h); 294 patients received continuous positive airway pressure therapy.

RESULTS

Analysis of covariance showed that NBP and the frequency of NBPFs were the highest in severe followed by moderate and mild OSA (all P < .001). Multivariable regression analysis revealed a significant association of NBPFs with AHI, body mass index, systolic NBP, and lowest SpO₂. The severity of OSA is also associated with the frequency of obesity, hypertension, diabetes mellitus, atrial fibrillation, heart failure (all P < .001), and coronary artery disease (P = .035). Short-term continuous positive airway pressure decreased the frequency of NBPFs in all OSA groups and the systolic NBP in severe and moderate but not in mild OSA.

CONCLUSIONS

The severity of OSA is associated with an increase in NBP and NBPFs. Continuous positive airway pressure reduces NBP parameters already after the first night. In addition to BP, the diagnosis and therapy of NBPFs should be considered in patients with OSA.

CLINICAL TRIAL REGISTRATION

Registry: German Clinical Trials Register; Name: Nocturnal blood pressure and nocturnal blood pressure fluctuations associated with the severity of obstructive sleep apnea; URL: https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00024087; Identifier: DRKS00024087.

CITATION

Picard F, Panagiotidou P, Tammen A-B, et al. Nocturnal blood pressure and nocturnal blood pressure fluctuations: the effect of short-term CPAP therapy and their association with the severity of obstructive sleep apnea. J Clin Sleep Med. 2022;18(2):361-371.

Effects of Continuous Positive Airway Pressure on Cell Adhesion Molecules in Patients with Obstructive Sleep Apnea: A Meta-Analysis

PURPOSE

Previous studies have confirmed that patients with obstructive sleep apnea (OSA) have higher systemic inflammatory markers, including intercellular adhesion molecule-1(ICAM-1), vascular cell adhesion molecule-1(VCAM-1), and E-selectin compared to control subjects. However, the effects of continuous positive airway pressure (CPAP) therapy on circulating levels of ICAM-1, VCAM-1, and E-selectin in OSA patients remain inconsistent. Therefore, the primary purpose of the present meta-analysis is to estimate the effect of CPAP therapy on these cell adhesion molecules (CAMs) in patients with OSA.

METHODS

The PubMed, Scopus, Embase, and Cochrane Library databases were searched. The overall effects were measured by the standardized mean difference (SMD) with a 95% confidence interval (CI). A random effects model or a fixed-effects model was used, depending on the heterogeneity of the studies.

RESULTS

A total of 11 studies were included, comprising 650 OSA patients. The pooled results showed that CPAP therapy significantly decreased ICAM-1 (SMD =  - 0.283, 95% CI   - 0.464 to - 0.101, p = 0.002) and E-selectin levels (SMD =  - 0.349, 95% CI   - 0.566 to - 0.133, p = 0.002). In contrast, there was no significant improvement of VCAM-1 levels after CPAP treatment (SMD =  - 0.160, 95% CI   - 0.641 to 0.320, p = 0.513).

CONCLUSIONS

Our meta-analysis demonstrated that CPAP treatment significantly decreased the circulating levels of ICAM-1 and E-selectin in OSA patients. Thus, ICAM-1 and E-selectin may be effective markers to evaluate CPAP therapy for reducing OSA cardiovascular risk in clinical practice.