Feasibility of portable sleep monitors to detect obstructive sleep apnea (OSA) in a vulnerable urban population

Enhancing Obstructive Sleep Apnea Diagnosis With Screening Through Disease Phenotypes: Algorithm Development and Validation

BACKGROUND

The American Academy of Sleep Medicine guidelines suggest that clinical prediction algorithms can be used in patients with obstructive sleep apnea (OSA) without replacing polysomnography, which is the gold standard.

OBJECTIVE

This study aims to develop a clinical decision support system for OSA diagnosis according to its standard definition (apnea-hypopnea index plus symptoms), identifying individuals with high pretest probability based on risk and diagnostic factors.

METHODS

A total of 47 predictive variables were extracted from a cohort of patients who underwent polysomnography. A total of 14 variables that were univariately significant were then used to compute the distance between patients with OSA, defining a hierarchical clustering structure from which patient phenotypes were derived and described. Affinity from individuals at risk of OSA phenotypes was later computed, and cluster membership was used as an additional predictor in a Bayesian network classifier (model B).

RESULTS

A total of 318 patients at risk were included, of whom 207 (65.1%) individuals were diagnosed with OSA (111, 53.6% with mild; 50, 24.2% with moderate; and 46, 22.2% with severe). On the basis of predictive variables, 3 phenotypes were defined (74/207, 35.7% low; 104/207, 50.2% medium; and 29/207, 14.1% high), with an increasing prevalence of symptoms and comorbidities, the latter describing older and obese patients, and a substantial increase in some comorbidities, suggesting their beneficial use as combined predictors (median apnea-hypopnea indices of 10, 14, and 31, respectively). Cross-validation results demonstrated that the inclusion of OSA phenotypes as an adjusting predictor in a Bayesian classifier improved screening specificity (26%, 95% CI 24-29, to 38%, 95% CI 35-40) while maintaining a high sensitivity (93%, 95% CI 91-95), with model B doubling the diagnostic model effectiveness (diagnostic odds ratio of 8.14).

CONCLUSIONS

Defined OSA phenotypes are a sensitive tool that enhances our understanding of the disease and allows the derivation of a predictive algorithm that can clearly outperform symptom-based guideline recommendations as a rule-out approach for screening.

The effect of CPAP therapy on excessive daytime sleepiness and quality of life in subjects with obstructive sleep apnoea: an AB design study

BACKGROUND

Obstructive sleep apnoea (OSA) is a disorder characterized by apnoeas and hypopnoeas due to repetitive upper airway collapse during sleep. So far, there are no published data regarding quality of life (QoL) and adherence to CPAP among patients with OSA in India. This study aims to measure sleepiness and QoL of patients before and after effective CPAP use in patients with OSA.

METHOD

Newly diagnosed subjects with OSA were included, and socio-demographic risk factors and anthropomorphic measures were collected. Epworth sleepiness scale (ESS) and short sleep apnoea quality of life index (SAQLI) were administered before and after a minimum of 4 weeks of domiciliary CPAP use. While short SAQLI is a disease-specific questionnaire, ESS measures excessive daytime sleepiness.

RESULTS

In 92 subjects age range was 28-74 years, mean age 49.7 ± 11.3 years, and male:female ratio was 70:22. Mean BMI was 32.1 ± 6.4 kg/sq.m; mean neck circumference was 39.4 ± 3.4 cm; 56 subjects had Mallampati score of 3 or 4. One-month follow-up was completed by 34 subjects who reported a mean of 5.8 ± 1.1 hours/night usage of CPAP. Mean ESS score was 11.31 ± 5.6 at baseline vs 6.9 ± 3.3 after 1 month (p = 0.02), and baseline short SAQLI score was at 2.54 ± 1.26 vs 1.38 ± 0.87 after 1 month (p = 0.0001).

CONCLUSIONS

Subjects reported adequate compliance with CPAP at 1 month, and both ESS and short SAQLI showed a significant improvement in these patients. CPAP compliance improved both QoL and sleepiness in patients with OSA.

Effects of continuous positive airway pressure (CPAP) therapy on neurological and functional rehabilitation in Basal Ganglia Stroke patients with obstructive sleep apnea: A prospective multicenter study

Obstructive sleep apnea (OSA) adversely affects neurological recovery. This study aimed to determine the impact of continuous positive airway pressure (CPAP) and/or rehabilitation in basal ganglia stroke patients with OSA.A prospective controlled trial was conducted in 2015-2018. The subjects received routine rehabilitation training for up to 2 years and were assigned to the intervention and control groups treated with CPAP or without, respectively. Then, treatment effects on sleep parameters, motor function, stroke severity, daily life activities, cognitive function, and psychological states were assessed at different time points.At 6 months, the CPAP group showed significantly lower mean apnea-hypopnea index (AHI), percentage of time with SpO2 at <90% (TS90%), micro-arousal index, and percentages of time in non-rapid eye movement (non-REM) stages 1-2 and REM stage in total sleeping time compared with the control group, and significantly higher mean minimum of peripheral oxygen saturation (L-SaO2%) and percentage of time in stage 3 (P < .001) sleep. The CPAP group showed significant improvements in average the National Institutes of Health Stroke Scale (NIHSS), Fugl-Meyer assessment scale (FMA), Barthel index (BI), Minimental state examination (MMSE), Hamilton anxiety scale (HAMA) and Hamilton depression rating scale for depression (HRSD) scores at different times versus the control group, respectively (P < .05). However, no difference in body mass index (BMI) management was observed (P > .05). Repeated-measures ANOVA revealed significant interactions between the two groups for change in FMA, MMSE, BI, HAMA, and HRSD scores from admission to 24 months (P < .001), but no significant was found for BMI (P = .582).Basal ganglia stroke patients with OSA tend to have significantly greater sleeping, neurological and functional recovery after CPAP, and rehabilitation over 2 years.

Methodological strategies in using home sleep apnea testing in research and practice

PURPOSE

Home sleep apnea testing (HSAT) has increased due to improvements in technology, accessibility, and changes in third party reimbursement requirements. Research studies using HSAT have not consistently reported procedures and methodological challenges. This paper had two objectives: (1) summarize the literature on use of HSAT in research of adults and (2) identify methodological strategies to use in research and practice to standardize HSAT procedures and information.

METHODS

Search strategy included studies of participants undergoing sleep testing for OSA using HSAT. MEDLINE via PubMed, CINAHL, and Embase with the following search terms: "polysomnography," "home," "level III," "obstructive sleep apnea," and "out of center testing."

RESULTS

Research articles that met inclusion criteria (n = 34) inconsistently reported methods and methodological challenges in terms of: (a) participant sampling; (b) instrumentation issues; (c) clinical variables; (d) data processing; and (e) patient acceptability. Ten methodological strategies were identified for adoption when using HSAT in research and practice.

CONCLUSIONS

Future studies need to address the methodological challenges summarized in this paper as well as identify and report consistent HSAT procedures and information.

Impact of obstructive sleep apnea on neurological recovery after ischemic stroke: A prospective study

OBJECTIVES

The presence of obstructive sleep apnea (OSA) has been found to adversely affect the neurological recovery after acute ischemic stroke (AIS) in previous observational studies. However, in most of these studies, diagnosis of OSA was based on oximetry data alone, raising concern in the accuracy of diagnosis as well as estimation of severity. Purpose of our study was to determine the prevalence and severity of OSA (based on polysomnography and American Association of Sleep Medicine [AASM] criteria) in patients with AIS and to compare the post-stroke neurological and functional outcome, in those with and without OSA.

MATERIALS AND METHODS

A prospective single-centre study was conducted over a period of eighteen months from January 2013. The demographic and clinical data were collected, and the etiology of stroke was classified according to TOAST classification. Subsequently, all selected patients (N=99) underwent premorbid sleep status assessment by Epworth Sleepiness Scale followed by polysomnography using Resmed ApneaLink polysomnograph. Data were analyzed to find out the prevalence and severity of OSA as well as its impact on neurological recovery as assessed by National Institutes of Health Stroke Scale (NIHSS) and modified Rankin scale (mRS) at different time points, starting from admission.

RESULTS

There was a high prevalence of OSA (~60%) with a quarter of them having severe OSA. The OSA group had a significantly higher mean NIHSS score at discharge (P=.002) and significantly higher mRS score (irrespective of severity of OSA) at all points of evaluation.

CONCLUSION

Ischemic stroke patients with OSA tend to have poor neurological and functional recovery, across all segments of stroke and OSA severity.