Habitual short sleepers with pre-existing medical conditions are at higher risk of Long COVID.

STUDY OBJECTIVES: Preliminary evidence suggests that the risk of Long COVID is higher among people with pre-existing medical conditions. Based on its proven adjuvant role in immunity, habitual sleep duration may alter the risk of developing Long COVID. The objective of this study was to determine whether the odds of Long COVID are higher among those with pre-existing medical conditions, and whether the strength of this association varies by habitual sleep duration. METHODS: Using data from 13,461 respondents from 16 countries who participated in the 2021 survey-based International COVID Sleep Study II (ICOSS II), we studied the associations between habitual sleep duration, pre-existing medical conditions, and Long COVID. RESULTS: Of 2,508 individuals who had COVID-19, 61% reported at least 1 Long COVID symptom. Multivariable logistic regression analysis showed that the risk of having Long COVID was 1.8-fold higher for average-length sleepers (6-9 h/night) with pre-existing medical conditions compared with those without pre-existing medical conditions (adjusted odds ratio [aOR] 1.84 [1.18-2.90]; P = .008). The risk of Long COVID was 3-fold higher for short sleepers with pre-existing medical conditions (aOR 2.95 [1.04-8.4]; P = .043) and not significantly higher for long sleepers with pre-existing conditions (aOR 2.11 [0.93-4.77]; P = .073) compared with average-length sleepers without pre-existing conditions. CONCLUSIONS: Habitual short nighttime sleep duration exacerbated the risk of Long COVID in individuals with pre-existing conditions. Restoring nighttime sleep to average duration represents a potentially modifiable behavioral factor to lower the odds of Long COVID for at-risk patients. CITATION: Berezin L, Waseem R, Merikanto I, et al. Habitual short sleepers with pre-existing medical conditions are at higher risk of long COVID. J Clin Sleep Med. 2024;20(1):111-119.

Do multiple physiological OCT biomarkers indicate age-related decline in rod mitochondrial function in C57BL/6J mice?

Purpose: To test the hypothesis that rod photoreceptor mitochondria function in vivo progressively declines over time. Methods: 2, 12, and 24 month-old dark- and light-adapted C57BL/6J (B6J) mice were examined by OCT. We measured (i) an index of mitochondrial configuration within photoreceptors measured from the profile shape aspect ratio (MCP/AR) of the hyperreflective band posterior to the external limiting membrane (ELM), (ii) a proxy for energy-dependent pH-triggered water removal, the thickness of the ELM-retinal pigment epithelium (ELM-RPE), and its correlate (iii) the hyporeflective band (HB) signal intensity at the photoreceptor tips. Visual performance was assessed by optokinetic tracking. Results: In 2 and 24 month-old mice, MCP/AR in both inferior and superior retina was smaller in light than in dark; no dark-light differences were noted in 12 month-old mice. Dark-adapted inferior and superior, and light-adapted superior, ELM-RPE thickness increased with age. The dark-light difference in ELM-RPE thickness remained constant across all ages. All ages showed a decreased HB signal intensity magnitude in dark relative to light. In 12 month-old mice, the dark-light difference in HB magnitude was greater than in younger and older mice. Anatomically, outer nuclear layer thickness decreased with age. Visual performance indices were reduced at 24 month-old compared to 2 month-old mice. Conclusion: While the working hypothesis was not supported herein, the results raise the possibility of a mid-life adaptation in rod mitochondrial function during healthy aging in B6J mice based on OCT biomarkers, a plasticity that occurred prior to declines in visual performance.

The effectiveness of supplemental oxygen and high-flow nasal cannula therapy in patients with obstructive sleep apnea in different clinical settings: A systematic review and meta-analysis.

STUDY OBJECTIVE: To evaluate the effectiveness of supplemental oxygen therapy and high-flow nasal cannula (HFNC) therapy in patients with obstructive sleep apnea (OSA) in different clinical settings to assess its application to surgical patients in the postoperative setting. DESIGN: A systematic search was conducted on MEDLINE and other databases from 1946 to December 16th, 2021. Title and abstract screening were conducted independently, and the lead investigators resolved conflicts. Meta-analyses were performed using a random-effects model and are presented as mean difference and standardized mean difference with 95% confidence intervals. These were calculated using RevMan 5.4. PATIENTS: 1395 and 228 OSA patients underwent oxygen therapy and HFNC therapy respectively. INTERVENTIONS: Oxygen therapy and HFNC therapy. MEASUREMENTS: Apnea-hypopnea index (AHI), oxyhemoglobin saturation (SpO2), cumulative time with SPO2 < 90% (CT90). MAIN RESULTS: Twenty-seven oxygen therapy studies were included in the review, with ten randomized controlled trials (RCT), seven randomized crossovers, seven non-randomized crossovers, and three prospective cohorts. Pooled analyses showed that oxygen therapy significantly reduced AHI by 31% and increased SpO2 by 5% versus baseline, and CPAP significantly reduced AHI by 84%, and increased SpO2 by 3% versus baseline. CPAP was 53% more effective in reducing AHI than oxygen therapy, but both treatments had similar effectiveness in increasing SpO2. Nine HFNC studies were included in the review, with five prospective cohorts, three randomized crossovers, and one RCT. Pooled analyses showed that HFNC therapy significantly reduced AHI by 36% but did not substantially increase SpO2. CONCLUSIONS: Oxygen therapy effectively reduces AHI and increases SpO2 in patients with OSA. CPAP is more effective in reducing AHI than oxygen therapy. HFNC therapy is effective in reducing AHI. Although both oxygen therapy and HFNC therapy effectively reduce AHI, more research is needed to draw conclusions on clinical outcomes.

Multiple Bioenergy-Linked OCT Biomarkers Suggest Greater-Than-Normal Rod Mitochondria Activity Early in Experimental Alzheimer's Disease.

Purpose: In Alzheimer's disease, central brain neurons show evidence for early hyperactivity. It is unclear if this occurs in the retina, another disease target. Here, we tested for imaging biomarker manifestation of prodromal hyperactivity in rod mitochondria in vivo in experimental Alzheimer's disease. Methods: Light- and dark-adapted 4-month-old 5xFAD and wild-type (WT) mice, both on a C57BL/6J background, were studied with optical coherence tomography (OCT). We measured the reflectivity profile shape of the inner segment ellipsoid zone (EZ) as a proxy for mitochondria distribution. Two additional indices responsive to mitochondria activity were also measured: the thickness of the external limiting membrane-retinal pigment epithelium (ELM-RPE) region and the signal magnitude of a hyporeflective band (HB) between photoreceptor tips and apical RPE. Retinal laminar thickness and visual performance were evaluated. Results: In response to low energy demand (light), WT mice showed the expected elongation in EZ reflectivity profile shape, relatively thicker ELM-RPE, and greater HB signal. Under high energy demand (dark), the EZ reflectivity profile shape was rounder, the ELM-RPE was thinner, and the HB was reduced. These OCT biomarker patterns for light-adapted 5xFAD mice did not match those of light-adapted WT mice but rather that of dark-adapted WT mice. Dark-adapted 5xFAD and WT mice showed the same biomarker pattern. The 5xFAD mice exhibited modest nuclear layer thinning and lower-than-normal contrast sensitivity. Conclusions: Results from three OCT bioenergy biomarkers raise the novel possibility of early rod hyperactivity in vivo in a common Alzheimer's disease model.

Transducin-Deficient Rod Photoreceptors Evaluated With Optical Coherence Tomography and Oxygen Consumption Rate Energy Biomarkers.

Purpose: To test the hypothesis that rod energy biomarkers in light and dark are similar in mice without functional rod transducin (Gnat1rd17). Methods: Gnat1rd17 and wildtype (WT) mice were studied in canonically low energy demand (light) and high energy demand (dark) conditions. We measured rod inner segment ellipsoid zone (ISez) profile shape, external limiting membrane-retinal pigment epithelium (ELM-RPE) thickness, and magnitude of a hyporeflective band (HB) intensity dip located between photoreceptor tips and apical RPE; antioxidants were given in a subset of mice. Oxygen consumption rate (OCR) and visual performance indexes were also measured. Results: The lower energy demand expected in light-adapted wildtype retinas was associated with an elongated ISez, thicker ELM-RPE, and higher HB magnitude, and lower OCR compared to high energy demand conditions in the dark. Gnat1rd17 mice showed a wildtype-like ISez profile shape at 20 minutes of light that became rounder at 60 minutes; at both times, ELM-RPE was smaller than wildtype values, and the HB magnitude was unmeasurable. OCR was higher than in the dark. Light-adapted Gnat1rd17 mice biomarkers were unaffected by anti-oxidants. Gnat1rd17 mice showed modest outer nuclear layer thinning and no reduction in visual performance indexes. Conclusions: Light-stimulated changes in all biomarkers in WT mice are consistent with the established light-induced decrease in net energy demand. In contrast, biomarker changes in Gnat1rd17 mice raise the possibility that light increases net energy demand in the absence of rod phototransduction.

Characteristics of Patients with Unrecognized Sleep Apnea Requiring Postoperative Oxygen Therapy.

Surgical patients with obstructive sleep apnea (OSA) have increased risk of perioperative complications. The primary objective is to determine the characteristics of surgical patients with unrecognized OSA requiring oxygen therapy for postoperative hypoxemia. The secondary objective is to investigate the characteristics of patients who were responsive to oxygen therapy. This was a post-hoc multicenter study involving patients with cardiovascular risk factors undergoing major non-cardiac surgery. Patients ≥45 years old underwent Type 3 sleep apnea testing and nocturnal oximetry preoperatively. Responders to oxygen therapy were defined as individuals with ≥50% reduction in oxygen desaturation index (ODI) on postoperative night 1 versus preoperative ODI. In total, 624 out of 823 patients with unrecognized OSA required oxygen therapy. These were mostly males, had larger neck circumferences, higher Revised Cardiac Risk Indices, higher STOP-Bang scores, and higher ASA physical status, undergoing intraperitoneal or vascular surgery. Multivariable regression analysis showed that the preoperative longer cumulative time SpO2 < 90% or CT90% (adjusted p = 0.03), and lower average overnight SpO2 (adjusted p < 0.001), were independently associated with patients requiring oxygen therapy. Seventy percent of patients were responders to oxygen therapy with ≥50% ODI reduction. Preoperative ODI (19.0 ± 12.9 vs. 14.1 ± 11.4 events/h, p < 0.001), CT90% (42.3 ± 66.2 vs. 31.1 ± 57.0 min, p = 0.038), and CT80% (7.1 ± 22.6 vs. 3.6 ± 8.7 min, p = 0.007) were significantly higher in the responder than the non-responder. Patients with unrecognized OSA requiring postoperative oxygen therapy were males with larger neck circumferences and higher STOP-Bang scores. Those responding to oxygen therapy were likely to have severe OSA and worse preoperative nocturnal hypoxemia. Preoperative overnight oximetry parameters may help in stratifying patients.

Functional Changes Within the Rod Inner Segment Ellipsoid in Wildtype Mice: An Optical Coherence Tomography and Electron Microscopy Study.

Purpose: To test the hypothesis that changing energy needs alter mitochondria distribution within the rod inner segment ellipsoid. Methods: In mice with relatively smaller (C57BL/6J [B6J]) or greater (129S6/ev [S6]) retina mitochondria maximum reserve capacity, the profile shape of the rod inner segment ellipsoid zone (ISez) was measured with optical coherence tomography (OCT) under higher (dark) or lower (light) energy demand conditions. ISez profile shape was characterized using an unbiased ellipse descriptor (minor/major aspect ratio). Other bioenergy indexes evaluated include the external limiting membrane-retinal pigment epithelium (ELM-RPE) thickness and the magnitude of the signal intensity of a hyporeflective band located between the photoreceptor tips and apical RPE. The spatial distribution of rod ellipsoid mitochondria were also examined with electron microscopy. Results: In B6J mice, darkness produced a greater ISez aspect ratio, thinner ELM-RPE, and a smaller hyporeflective band intensity than in light. In S6 mice, dark and light ISez aspect ratio values were not different and were greater than in light-adapted B6J mice; dark-adapted S6 mice showed smaller ELM-RPE thinning versus light, and negligible hyporeflective band intensity in the light. In B6J mice, mitochondria number in light increased in the distal inner segment ellipsoid and decreased proximally. In S6 mice, mitochondria number in the inner segment ellipsoid were not different between light and dark, and were greater than in B6J mice. Conclusions: These data raise the possibility that rod mitochondria activity in mice can be noninvasively evaluated based on the ISez profile shape, a new OCT index that complements OCT energy biomarkers measured outside of the ISez region.

Preoperative oximetry-derived hypoxemia predicts postoperative cardiovascular events in surgical patients with unrecognized obstructive sleep apnea.

STUDY OBJECTIVE: Obstructive sleep apnea (OSA) is known to be associated with postoperative cardiovascular events in patients undergoing major non-cardiac surgery. The objective of the study is to determine whether preoperative oximetry-derived hypoxemia predicts postoperative cardiovascular events in surgical patients with unrecognized obstructive sleep apnea. DESIGN AND SETTING: The study was a planned post hoc analyses of a multicenter prospective cohort study. PATIENTS: The inclusion criteria were patients ≥45 years old undergoing major non-cardiac surgery with cardiovascular risk factors. INTERVENTIONS AND MEASUREMENTS: All patients underwent pre-operative pulse oximetry (PULSOX-300i, Konica-Minolta Sensing, Inc). The severity of OSA was classified based on oxygen desaturation index (ODI) (mild: ≥5 to <15, moderate: ≥15 to <30, and severe OSA: ≥30 events/h). The 30 days cardiovascular events were a composite of myocardial injury, cardiac death, congestive heart failure, thromboembolism, atrial fibrillation, and stroke. MAIN RESULTS: For 1218 patients with mild, moderate, or severe OSA (mean age: 67.2 ± 9.3 years; body mass index: 27.0 ± 5.3 kg/m2), the rate of postoperative cardiovascular events was 16.4%, 25.2%, and 29.8% respectively. The multivariable analysis showed that preoperative oxygen desaturation index (ODI) ≥30 events per hour {adjusted hazard ratio (aHR) 1.63 [95% confidence interval (CI): 1.05-2.53]}, and cumulative time spent during sleep with oxygen saturation below 80% (CT80) ≥10 min {aHR 1.79 [95% CI: 1.28-2.50]} were independent predictors of 30-day postoperative cardiovascular events. CONCLUSIONS: Preoperative ODI ≥30 events per hour and CT80 ≥ 10 min are associated with increased risk of postoperative cardiovascular events. Preoperative screening using oximetry helps in risk stratification for unrecognized sleep apnea. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01494181.

Incidence and Predictive Factors of Acute Kidney Injury After Off-pump Lung Transplantation.

OBJECTIVES: To determine the incidence and predictive factors of acute kidney injury (AKI) after off-pump lung transplantation. DESIGN: A retrospective cohort study. SETTING: The operating room and intensive care unit. PARTICIPANTS: Adult patients who underwent lung transplant without cardiopulmonary bypass or extracorporeal membrane oxygenator between 2006 and 2016 at the Vanderbilt University Medical Center. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The presence of postoperative AKI was assessed by the Kidney Disease: Improving Global Outcomes criteria in the first seven postoperative days. Multivariate logistic regression analysis was used to determine the independent predictive factors of AKI. One hundred forty-eight patients were included in the final analysis, of whom 63 (42.6%) subsequently developed AKI: 43 (29.0%) stage 1, ten (6.8%) stage 2, and ten (6.8%) stage 3. Patients who had AKI had a longer hospital length of stay (12 days [interquartile range (IQR): 10-17] vs ten days [IQR: 8-12], p < 0.001). For every one-year increase in age, the odds of AKI decreased by 8% (odds ratio [OR] 0.92, 95% confidence interval [CI]: 0.87-0.98, p = 0.008). The odds of having AKI in patients with bilateral lung transplant was lower than patients with unilateral transplant (OR 0.09, 95% CI: 0.01-0.63, p = 0.015). Additionally, a diagnosis of chronic obstructive pulmonary disease increased the odds of AKI by four-fold compared with a diagnosis of idiopathic pulmonary fibrosis (OR 4.73, 95% CI: 1.44-15.56, p = 0.011). CONCLUSIONS: AKI is a common complication after off-pump lung transplantation and is associated with increased hospital length of stay. Younger age, unilateral lung transplant, and diagnosis of chronic obstructive pulmonary disease are independently associated with AKI.

Can the complete blood count be used as a reliable screening tool for obstructive sleep apnea?

PURPOSE: Since hypoxia increases erythropoietin production and inflammation, the complete blood count (CBC) has been proposed as an inexpensive alternative for obstructive sleep apnea (OSA) screening. The objective of this study was to determine whether or not intermittent hypoxia and OSA severity, as measured by the mean oxygen saturation (SpO2) and apnea-hypopnea index (AHI), affect parameters measured by the CBC. METHODS: This retrospective study included a total of 941 surgical patients who had a pre-operative home sleep study. The pre-operative CBC was extracted from the electronic patient records. Patients were stratified according to their AHI scores, into mild (AHI ≥ 5 - < 15), moderate (AHI ≥ 15 - < 30), and severe (AHI ≥ 30) OSA groups. RESULTS: There were 244 patients without OSA, 294 with mild, 223 with moderate, and 180 with severe OSA. Our analysis showed that hemoglobin (P = 0.010), hematocrit (P = 0.027), and basophils (P = 0.006) showed significant changes among the different severities of OSA. For mean SpO2, there were negative associations with body mass index (r = - 0.287; P < 0.001), age (r = - 0.077; P = 0.021), hemoglobin (r = - 0.208; P < 0.001), hematocrit (r = - 0.220; P < 0.001), red blood cells (r = - 0.107; P = 0.001), mean corpuscular volume (MCV) (r = - 0.159; P < 0.001), mean corpuscular hemoglobin (r = - 0.142; P < 0.001), and basophils (r = - 0.091; P = 0.007). All analyzed parameters remained within normal clinical range. Multivariable regression identified hemoglobin, MCV, and basophils to be independent predictors of mean SpO2 and AHI. CONCLUSION: Hemoglobin, MCV, and basophils were independently associated with intermittent hypoxia defined by mean SpO2 and AHI. Adding CBC parameters to other screening tools for OSA may have additional value due to its association with changes in mean SpO2.

Prevalence of preoperative cognitive impairment in older surgical patients.: A systematic review and meta-analysis.

STUDY OBJECTIVE: Older surgical patients with cognitive impairment are at an increased risk for adverse perioperative outcomes, however the prevalence of preoperative cognitive impairment is not well-established within this population. The purpose of this review is to determine the pooled prevalence of preoperative cognitive impairment in older surgical patients. DESIGN: Systematic review and meta-analysis. SETTING: MEDLINE (Ovid), PubMed (non-MEDLINE records only), Embase, Cochrane Central, Cochrane Database of Systematic Reviews, PsycINFO, and EMCare Nursing for relevant articles from 1946 to April 2021. PATIENTS: Patients aged ≥60 years old undergoing surgery, and preoperative cognitive impairment assessed by validated cognitive assessment tools. INTERVENTIONS: Preoperative assessment. MEASUREMENTS: Primary outcomes were the pooled prevalence of preoperative cognitive impairment in older patients undergoing either elective (cardiac or non-cardiac) or emergency surgery. MAIN RESULTS: Forty-eight studies (n = 42,498) were included. In elective non-cardiac surgeries, the pooled prevalence of unrecognized cognitive impairment was 37.0% (95% confidence interval [CI]: 30.0%, 45.0%) among 27,845 patients and diagnosed cognitive impairment was 18.0% (95% CI: 9.0%, 33.0%) among 11,676 patients. Within the elective non-cardiac surgery category, elective orthopedic surgery was analyzed. In this subcategory, the pooled prevalence of unrecognized cognitive impairment was 37.0% (95% CI: 26.0%, 49.0%) among 1117 patients, and diagnosed cognitive impairment was 17.0% (95% CI: 3.0%, 60.0%) among 6871 patients. In cardiac surgeries, the unrecognized cognitive impairment prevalence across 588 patients was 26.0% (95% CI: 15.0%, 42.0%). In emergency surgeries, the unrecognized cognitive impairment prevalence was 50.0% (95% CI: 35.0%, 65.0%) among 2389 patients. CONCLUSIONS: A substantial number of surgical patients had unrecognized cognitive impairment. In elective non-cardiac and emergency surgeries, the pooled prevalence of unrecognized cognitive impairment was 37.0% and 50.0%. Preoperative cognitive screening warrants more attention for risk assessment and stratification.

Virtual preoperative assessment in surgical patients: A systematic review and meta-analysis.

STUDY OBJECTIVE: Preoperative assessment is a standard evaluation, traditionally done in-person in a preanesthesia clinic, for patients who will be undergoing a procedure involving anesthesia. Given the increased adoption of virtual care during the coronavirus disease 2019 (COVID-19) pandemic, the purpose of this systematic review and meta-analysis is to review the effectiveness of virtual preoperative assessment for the evaluation of surgical patients. DESIGN: Systematic review and meta-analysis. SETTING: MEDLINE (Ovid), MEDLINE InProcess/ePubs, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and ClinicalTrials.gov were searched from the initial coverage of the respective database to May 2021. A manual citation search of Google Scholar and PubMed was conducted to identify missed articles. Continued literature surveillance was done through July 2021. PATIENTS: Patients aged 18 years and older undergoing virtual preoperative anesthesia assessment. INTERVENTIONS: Virtual preoperative assessment. MEASUREMENTS: Surgery cancellation rates, patient experience, resources saved, staff experience, success in using the data collected to diagnose and manage patients. MAIN RESULTS: Fifteen studies (n = 31,496 patients) were included in this review. The average age of patients was 58 ± 15 years, and 47% were male. Virtual preoperative assessment resulted in similar surgery cancellation rates compared to in-person evaluation, with a pooled cancellation rate of 2% (95% confidence interval [CI]: 1-3%). Most studies reported a positive patient experience, with a pooled estimate of 90% (95% CI, 81-95%). There was a high success rate in using the information collected with virtual care, in the range of 92-100%, to diagnose and manage patients resulting in time and cost savings in the range of 24-137 min and $60-67 per patient. CONCLUSIONS: This systematic review and meta-analysis demonstrates the utility of virtual care for preoperative assessment of surgical patients. Virtual preanesthesia evaluation had similar surgery cancellation rates, high patient satisfaction, and reduced costs compared to in-person evaluation.

Simple screening model for identifying the risk of sleep apnea in patients on opioids for chronic pain.

BACKGROUND: There is an increased risk of sleep apnea in patients using opioids for chronic pain. We hypothesized that a simple model comprizing of: (1) STOP-Bang questionnaire and resting daytime oxyhemoglobin saturation (SpO2); and (2) overnight oximetry will identify those at risk of moderate-to-severe sleep apnea in patients with chronic pain. METHOD: Adults on opioids for chronic pain were recruited from pain clinics. Participants completed the STOP-Bang questionnaire, resting daytime SpO2, and in-laboratory polysomnography. Overnight oximetry was performed at home to derive the Oxygen Desaturation Index. A STOP-Bang score ≥3 or resting daytime SpO2 ≤95% were used as thresholds for the first step, and for those identified at risk, overnight oximetry was used for further screening. The Oxygen Desaturation Index from overnight oximetry was validated against the Apnea-Hypopnea Index (≥15 events/hour) from polysomnography. RESULTS: Of 199 participants (52.5±12.8 years, 58% women), 159 (79.9%) had a STOP-Bang score ≥3 or resting SpO2 ≤95% and entered the second step (overnight oximetry). Using an Oxygen Desaturation Index ≥5 events/hour, the model had a sensitivity of 86.4% and specificity of 52% for identifying moderate-to-severe sleep apnea. The number of participants who would require diagnostic sleep studies was decreased by 38% from Step 1 to Step 2 of the model. CONCLUSION: A simple model using STOP-Bang questionnaire and resting daytime SpO2, followed by overnight oximetry, can identify those at high risk of moderate-to-severe sleep apnea in patients using opioids for chronic pain. TRIAL REGISTRATION NUMBER: NCT02513836.

Predictive performance of oximetry in detecting sleep apnea in surgical patients with cardiovascular risk factors.

INTRODUCTION: In adults with cardiovascular risk factors undergoing major noncardiac surgery, unrecognized obstructive sleep apnea (OSA) was associated with postoperative cardiovascular complications. There is a need for an easy and accessible home device in predicting sleep apnea. The objective of the study is to determine the predictive performance of the overnight pulse oximetry in predicting OSA in at-risk surgical patients. METHODS: This was a planned post-hoc analysis of multicenter prospective cohort study involving 1,218 at-risk surgical patients without prior diagnosis of sleep apnea. All patients underwent home sleep apnea testing (ApneaLink Plus, ResMed) simultaneously with pulse oximetry (PULSOX-300i, Konica Minolta Sensing, Inc). The predictive performance of the 4% oxygen desaturation index (ODI) versus apnea-hypopnea index (AHI) were determined. RESULTS: Of 1,218 patients, the mean age was 67.2 ± 9.2 years and body mass index (BMI) was 27.0 ± 5.3 kg/m2. The optimal cut-off for predicting moderate-to-severe and severe OSA was ODI ≥15 events/hour. For predicting moderate-to-severe OSA (AHI ≥15), the sensitivity and specificity of ODI ≥ 15 events per hour were 88.4% (95% confidence interval [CI], 85.7-90.6) and 95.4% (95% CI, 94.2-96.4). For severe OSA (AHI ≥30), the sensitivity and specificity were 97.2% (95% CI, 92.7-99.1) and 78.8% (95% CI, 78.2-79.0). The area under the curve (AUC) for moderate-to-severe and severe OSA was 0.983 (95% CI, 0.977-0.988) and 0.979 (95% CI, 0.97-0.909) respectively. DISCUSSION: ODI from oximetry is sensitive and specific in predicting moderate-to-severe or severe OSA in at-risk surgical population. It provides an easy, accurate, and accessible tool for at-risk surgical patients with suspected OSA.

Perioperative adherence to continuous positive airway pressure and its effect on postoperative nocturnal hypoxemia in obstructive sleep apnea patients: a prospective cohort study.

BACKGROUND: Although continuous positive airway pressure (CPAP) is the first line treatment for obstructive sleep apnea (OSA) patients, the perioperative adherence rate is unclear. The objective of this study was to determine the perioperative adherence rate of patients with OSA with a CPAP prescription and the effect of adherence on nocturnal oxygen saturation. METHODS: This prospective cohort study included adult surgical patients with a diagnosis of OSA with CPAP prescription undergoing elective non-cardiac surgery. Patients were divided into CPAP adherent and non-adherent groups based on duration of usage (≥ 4 h/night). Overnight oximetry was performed preoperatively and on postoperative night 1 and 2 (N1, N2). The primary outcome was adherence rate and the secondary outcome was nocturnal oxygen saturation. RESULTS: One hundred and thirty-two patients completed the study. CPAP adherence was 61% preoperatively, 58% on postoperative N1, and 59% on N2. Forty-nine percent were consistently CPAP adherent pre- and postoperatively. Using a linear fixed effects regression, oxygen desaturation index (ODI) was significantly improved by CPAP adherence (p = 0.0011). The interaction term CPAP x N1 was significant (p = 0.0015), suggesting that the effect of CPAP adherence varied on N1 vs preoperatively. There was no benefit of CPAP adherence on postoperative mean SpO2, minimum SpO2, and percentage of sleep duration with SpO2 < 90%. Use of supplemental oxygen therapy was much lower in the CPAP adherent group vs non-adherent group (9.8% vs 46.5%, p <  0.001). CONCLUSIONS: Among patients with a preoperative CPAP prescription, approximately 50% were consistently adherent. CPAP adherence was associated with improved preoperative ODI and the benefit was maintained on N1. These modest effects may be underestimated by a higher severity of OSA in the CPAP adherent group and a higher rate of oxygen supplementation in the non-adherent group. TRIAL REGISTRATION: ClinicalTrials.Gov registry ( NCT02796846 ).

Predictive Performance of Oximetry to Detect Sleep Apnea in Patients Taking Opioids.

BACKGROUND: Long-term use of opioids for treatment of chronic pain is associated with significant risks including worsening unrecognized or untreated sleep apnea that may increase morbidity and mortality. Overnight oximetry has been validated for predicting sleep apnea in surgical and sleep clinic patients. The objective of the study was to assess the predictive accuracy of oxygen desaturation index (ODI 4%) from home overnight oximetry when compared to apnea hypopnea index (AHI) from polysomnography for predicting sleep apnea in patients taking opioids for chronic pain. METHODS: This was a planned post hoc analysis of a prospective cohort study conducted at 5 pain clinics. Patient characteristics and daily morphine milligram equivalent (MME) dose were recorded. All consented patients underwent home overnight oximetry (PULSOX-300i, Konica Minolta Sensing, Inc, Osaka, Japan) and in-laboratory polysomnography. The predictive performance of ODI 4% from oximetry was assessed against AHI from polysomnography. RESULTS: Among 332 consented patients, 181 with polysomnography and overnight oximetry data were analyzed. The mean age and body mass index of 181 patients were 52 ± 13 years and 29 ± 6 kg/m2, respectively, with 40% men. The area under the receiver operating curve for ODI to predict moderate-to-severe sleep apnea (AHI ≥15 events/h) and severe sleep apnea (AHI ≥30 events/h) was 0.82 (95% confidence interval [CI], 0.75-0.88) and 0.87 (95% CI, 0.80-0.94). ODI ≥5 events/h had a sensitivity of 85% (95% CI, 74-92) and specificity of 57% (95% CI, 52-61) to predict moderate-to-severe sleep apnea. ODI ≥15 events/h had a sensitivity of 71% (95% CI, 55-83) and specificity of 88% (95% CI, 84-91) to predict severe sleep apnea. CONCLUSIONS: Overnight home oximetry has a high predictive performance in predicting moderate-to-severe and severe sleep apnea in patients on opioids for chronic pain. It is a useful additional tool for health care providers for the screening of sleep apnea in this high-risk group.

The association between high risk of sleep apnea, comorbidities, and risk of COVID-19: a population-based international harmonized study.

PURPOSE: Obstructive sleep apnea (OSA) may increase the risk of severe COVID-19; however, the level of potential modulation has not yet been established. The objective of the study was to determine the association between high risk of OSA, comorbidities, and increased risk for COVID-19, hospitalization, and intensive care unit (ICU) treatment. METHODS: We conducted a cross-sectional population-based web survey in adults in 14 countries/regions. The survey included sociodemographic variables and comorbidities. Participants were asked questions about COVID-19, hospitalization, and ICU treatment. Standardized questionnaire (STOP questionnaire for high risk of OSA) was included. Multivariable logistic regression was conducted adjusting for various factors. RESULTS: Out of 26,539 respondents, 20,598 (35.4% male) completed the survey. Mean age and BMI of participants were 41.5 ± 16.0 years and 24.0 ± 5.0 kg/m2, respectively. The prevalence of physician-diagnosed OSA was 4.1% and high risk of OSA was 9.5%. We found that high risk of OSA (adjusted odds ratio (aOR) 1.72, 95% confidence interval (CI): 1.20, 2.47) and diabetes (aOR 2.07, 95% CI: 1.23, 3.48) were associated with reporting of a COVID-19 diagnosis. High risk for OSA (aOR 2.11, 95% CI: 1.10-4.01), being male (aOR: 2.82, 95% CI: 1.55-5.12), having diabetes (aOR: 3.93, 95% CI: 1.70-9.12), and having depression (aOR: 2.33, 95% CI: 1.15-4.77) were associated with increased risk of hospitalization or ICU treatment. CONCLUSIONS: Participants at high risk of OSA had increased odds of having COVID-19 and were two times more likely to be hospitalized or treated in ICU.

Use and Performance of the STOP-Bang Questionnaire for Obstructive Sleep Apnea Screening Across Geographic Regions: A Systematic Review and Meta-Analysis.

Importance: Obstructive sleep apnea (OSA) is a highly prevalent global health concern and is associated with many adverse outcomes for patients. Objective: To evaluate the utility of the STOP-Bang (snoring, tiredness, observed apnea, blood pressure, body mass index, age, neck size, gender) questionnaire in the sleep clinic setting to screen for and stratify the risk of OSA among populations from different geographical regions. Data Sources and Study Selection: MEDLINE, MEDLINE In-process, Embase, EmCare Nursing, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, PsycINFO, Journals@Ovid, Web of Science, Scopus, and CINAHL electronic databases were systematically searched from January 2008 to March 2020. This was done to identify studies that used the STOP-Bang questionnaire and polysomnography testing in adults referred to sleep clinics. Data Extraction and Synthesis: Clinical and demographic data were extracted from each article independently by 2 reviewers. The combined test characteristics were calculated using 2 × 2 contingency tables. Random-effects meta-analyses and metaregression with sensitivity analyses were performed. The Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) guideline was followed. Main Outcomes and Measures: The combined test characteristics and area under summary receiver operating characteristic curves (AUCs) were used to compare STOP-Bang questionnaire accuracy with polysomnography testing. Results: A total of 47 studies with 26 547 participants (mean [SD] age, 50 [5] years; mean [SD] body mass index, 32 [3]; 16 780 [65%] men) met the criteria for the systematic review. Studies were organized in different geographic regional groups: North America, South America, Europe, Middle East, East Asia, and South or Southeast Asia. The prevalence rates for all OSA, moderate to severe OSA, and severe OSA were 80% (95% CI, 80%-81%), 58% (95% CI, 58%-59%), and 39% (95% CI, 38%-39%), respectively. A STOP-Bang score of at least 3 had excellent sensitivity (>90%) and high discriminative power to exclude moderate to severe and severe OSA, with negative predictive values of 77% (95% CI, 75%-78%) and 91% (95% CI, 90%-92%), respectively. The diagnostic accuracy of a STOP-Bang score of at least 3 to detect moderate to severe OSA was high (>0.80) in all regions except East Asia (0.52; 95% CI, 0.48-0.56). Conclusions and Relevance: The results of this meta-analysis suggest that the STOP-Bang questionnaire can be used as a screening tool to assist in triaging patients with suspected OSA referred to sleep clinics in different global regions.

Diagnostic performance of the STOP-Bang questionnaire as a screening tool for obstructive sleep apnea in different ethnic groups.

STUDY OBJECTIVES: The STOP-Bang questionnaire is a concise and easy screening tool for obstructive sleep apnea (OSA). Using modified body mass index (BMI), we assessed the diagnostic performance of the STOP-Bang questionnaire in predicting OSA in ethnically different groups of patients undergoing surgery. METHODS: This was a multicenter prospective cohort study involving patients with cardiovascular risk factors who were undergoing major noncardiac surgery. Patients underwent home sleep apnea testing. All patients completed the STOP-Bang questionnaire. The predictive parameters of STOP-Bang scores were calculated against the apnea-hypopnea index. RESULTS: From 4 ethnic groups 1,205 patients (666 Chinese, 161 Indian, 195 Malay, and 183 Caucasian) were included in the study. The mean BMI ranged from 25 ± 4 to 30 ± 6 kg/m² and mean age ranged from 64 ± 8 to 71 ± 10 years. For the Chinese and Indian patients, diagnostic parameters are presented using BMI threshold of 27.5 kg/m² with the area under curve to predict moderate-to-severe OSA being 0.709 (0.665-0.753) and 0.722 (0.635-0.808), respectively. For the Malay and Caucasian, diagnostic parameters are presented using BMI threshold of 35 kg/m² with the area under curve for predicting moderate-to-severe OSA being 0.645 (0.572-0.720) and 0.657 (0.578-0.736), respectively. Balancing the sensitivity and specificity, the optimal STOP-Bang thresholds for the Chinese, Indian, Malay, and Caucasian groups were determined to be 4 or greater. CONCLUSIONS: For predicting moderate-to-severe OSA, we recommend BMI threshold of 27.5 kg/m² for Chinese and Indian patients and 35 kg/m² for Malay and Caucasian patients. The optimal STOP-Bang threshold for the Chinese, Indian, Malay and Caucasian groups is 4 or greater. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov; Name: Postoperative Vascular Events in Unrecognized Obstructive Sleep Apnea; URL: https://clinicaltrials.gov/ct2/show/study/NCT01494181; Identifier: NCT01494181.

Treatment for patients with sleep apnea on opioids for chronic pain: results of the OpSafe trial.

STUDY OBJECTIVES: Approximately 20% of North Americans are afflicted with chronic pain with 3% being opioid users. The objective was to determine whether patients on opioids for chronic pain with newly diagnosed sleep apnea attended sleep clinic review and followed treatment recommendations. METHODS: The study was a post hoc analysis from a multicenter perspective cohort study. Inclusion criteria included adults taking opioid medications for chronic pain for >3 months. Demographic data and daily opioid dose were collected. Sleep apnea was diagnosed via level 1 polysomnography. Patients who attended sleep clinic review were grouped based on the types of treatment they received. RESULTS: A total of 204 patients completed polysomnography and 58.8% were diagnosed to have sleep apnea (apnea-hypopnea index ≥5 events/h). Of those with sleep apnea, 58% were recommended to have an evaluation by a sleep physician. Body mass index and age were 29.5 ± 6 kg/m² and 56 ± 12 years, respectively. Of those with newly diagnosed sleep apnea, 25% received treatment, with the majority being treated with positive airway pressure therapy, whereas the rest received positional therapy and opioids/sedative reduction. The adherence rate of positive airway pressure therapy was 55% at 1 year. Over 50% of participants on opioids for chronic pain with newly diagnosed sleep apnea declined attendance for sleep clinic review or treatment. CONCLUSIONS: There was a high refusal rate to attend clinic for treatment. Adherence to positive airway pressure therapy was low at 55%. This sheds light on the high rate of treatment nonadherence and the need for further research. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov; Name: Opioid Safety Program in Pain Clinics (Op-Safe); URL: https://www.clinicaltrials.gov/ct2/show/NCT02513836; Identifier: NCT02513836.