METHODS: A cross-sectional study was carried out using a systematic random sampling method in hypertensive patients who attended two government primary care clinics in Sarawak. The STOP-Bang questionnaire was used to screen for OSA, and social-demographic data was captured with a questionnaire. Multiple logistic regressions were used to examine the determinants of the OSA.
RESULTS: A total of 410 patients were enrolled in this study. The mean age of study population patients was 56.4 years, with more than half being female. The mean blood pressure was 136/82. The prevalence of probable OSA among patients with hypertension was 54.4%. According to multiple logistic regression analyses, smoking (odds ratio [OR] 14.37, 95% confidence interval [CI] 3.335-61.947), retirees (OR 3.20, 95% CI 1.675-6.113), and being Chinese (OR 2.21, 95% CI 1.262-3.863) had a significant positive association with probable OSA.
CONCLUSIONS: Because of the high prevalence of probable OSA among patients with hypertension, primary care physicians should be more vigilant in identifying hypertensive patients with OSA risk. Early detection and intervention would reduce disease complications and healthcare costs.
METHODS: Children having home overnight oximetry for suspected OSA were identified over 12 months, and those with a normal result who went on to have polysomnography (PSG) were included. Oximetry, including PR-SD and PRI (rises of 8, 10 and 15 beats/min per hour), was analyzed using commercially available software. PR parameters were compared between those with OSA (obstructive apnoea-hypopnoea index (OAHI) >1 event/h) and those without OSA.
RESULTS: One hundred sixteen children had normal oximetry, of whom 93 (median age 4.5 years; 55 % M) had PSG. Fifty-seven of 93 (61 %) children had OSA (median OAHI 4.5 events/h, range 1.1-24). PR-SD was not different between the OSA and non-OSA groups (p = 0.87). PRI tended to be higher in those with OSA, but there was considerable overlap between the groups: PRI-8 (mean ± SD 58.5 ± 29.0/h in OSA group vs 48.6 ± 20.2/h in non-OSA group, p = 0.07), PRI-10 (45.1 ± 25.0 vs 36.2 ± 16.7, p = 0.06) and PRI-15 (24.4 ± 14.5 vs 18.9 ± 9.0, p = 0.04). A PRI-15 threshold of >35/h had specificity of 97 % for OSA.
CONCLUSION: The PRI-15 shows promise as an indicator of OSA in children with normal oximetry.
METHODS: This was a prospective, observational cohort study replacing the undivided nasal cannula with a divided nasal cannula during routine polysomnography (n = 28).
RESULTS: Integration of the divided nasal cannula pressure transducer system into routine polysomnography was easy and affordable. Most patients (89%) demonstrated nasal cycle changes during the test. Nasal cycle changes tended to occur during body position changes (62%) and transitions from non-rapid eye movement sleep to rapid eye movement sleep (41%). The mean nasal cycle duration was 2.5 ± 2.1 hours. Other sleep study metrics did not reveal statistically significant findings in relation to the nasal cycle.
CONCLUSIONS: Replacing an undivided nasal cannula with a divided nasal cannula is easy to implement, adding another physiologic measure to polysomnography. Although the divided nasal cannula did not significantly affect traditional polysomnographic metrics such as the apnea-hypopnea index or periodic limb movement index based on this small pilot study, we were able to replicate past nasal cycle findings that may be of interest to sleep clinicians and researchers. Given the ease with which the divided nasal cannula can be integrated, we encourage other sleep researchers to investigate the utility of using a divided nasal cannula during polysomnography.