Does a Low Arousal Threshold Equal Low PAP Adherence?

Association between air pollutant exposure, body water distribution and sleep disorder indices in individuals with low-arousal-threshold obstructive sleep apnoea

BACKGROUND

Air pollution may alter body water distribution, it may also be linked to low-arousal-threshold obstructive sleep apnoea (low-ArTH OSA). Here, we explored the mediation effects of air pollution on body water distribution and low-ArTH OSA manifestations.

METHODS

In this retrospective study, we obtained sleep centre data from healthy participants and patients with low-ArTH OSA (N=1924) in northern Taiwan. Air pollutant exposure at different time intervals (1, 3, 6 and 12 months) was estimated using the nearest station estimation method, and government air-quality data were also obtained. Regression models were used to assess the associations of estimated exposure, sleep disorder indices and body water distribution with the risk of low-ArTH OSA. Mediation analysis was performed to explore the relationships between air pollution, body water distribution and sleep disorder indices.

RESULTS

First, exposure to particulate matter (PM) with a diameter of ≤10 µm (PM10) for 1 and 3 months and exposure to PM with a diameter of ≤2.5 µm (PM2.5) for 3 months were significantly associated with the Apnoea-Hypopnoea Index (AHI), Oxygen Desaturation Index (ODI), Arousal Index (ArI) and intracellular-to-extracellular water ratio (I-E water ratio). Significant associations were observed between the risk of low-ArTH OSA and 1- month exposure to PM10 (OR 1.42, 95% CI 1.09 to 1.84), PM2.5 (OR 1.33, 95% CI 1.02 to 1.74) and ozone (OR 1.27, 95% CI 1.01 to 1.6). I-E water ratio alternation caused by 1-month exposure to PM10 and 3-month exposure to PM2.5 and PM10 had partial mediation effects on AHI and ODI.

CONCLUSION

Air pollution can directly increase sleep disorder indices (AHI, ODI and ArI) and alter body water distribution, thus mediating the risk of low-ArTH OSA.

A randomized, placebo-controlled trial using a novel PAP delivery platform to treat patients with OSA and comorbid PTSD

PURPOSE

Positive airway pressure (PAP) adherence is poor in comorbid OSA/PTSD. SensAwake™ (SA) is a wake-sensing PAP algorithm that lowers pressure when wake is detected. We compared auto-PAP (aPAP) with and without SA for comorbid OSA/PTSD.

METHODS

Prospective, randomized crossover study comparing aPAP to aPAP + SA. We enrolled patients with OSA/PTSD who were PAP naïve. Four weeks after randomization, the patients were crossed over to the alternate treatment group, with final follow-up at eight weeks. Sleep questionnaires (ESS, ISI, FSS, and FOSQ-10) were assessed at baseline and follow-up.

RESULTS

We enrolled 85 patients with OSA/PTSD. aPAP reduced AHI to < 5/h in both groups. Our primary endpoint, average hours of aPAP adherence (total) after 4 weeks, was significantly increased in the SA group in our intention-to-treat (ITT) analysis (ß = 1.13 (95% CI 0.16-2.1); p = 0.02), after adjustment for ESS differences at baseline. After adjustment for ESS, SA (ITT analysis) also showed significant improvement in percentage of nights used for ≥ 4 h (ß = 14.9 (95% CI 1.02-28.9); p = 0.04). There were trends toward an increase in percentage nights used total (ß = 17.4 (95% CI - 0.1 to 34.9); p = 0.05), average hours of aPAP adherence (nights used) (ß = 1.04 (95% CI - 0.07 to 2.1); p = 0.07), and regular use (OR = 7.5 (95% CI 0.9-64.7); p = 0.07) after adjustment for ESS at baseline. After adjustment for ESS and days to cross over, SA by actual assignment did not show any effect on adherence variables. The ESS, ISI, FSS, and FOSQ-10 all showed significant improvements with PAP, but there were no differences in the magnitude of improvement in any score between groups.

CONCLUSIONS

Adherence to aPAP may be improved with the addition of SA and deserves further study. SA is as effective as standard aPAP for normalizing the AHI and improving sleep-related symptoms.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT02549508 https://clinicaltrials.gov/ct2/show/NCT02549508?term=NCT02549508&rank=1 "Comparison Study Using APAP With and Without SensAwake in Patients With OSA and PTSD".