Waist-To-Hip Ratio Predicts Abnormal Overnight Oximetry in Men Independent of Body Mass Index

Background: Ambulatory overnight oximetry (OXI) has emerged as a cost-effective initial test for sleep disordered breathing. Obesity is closely associated with obstructive sleep apnea (OSA); however, whether body mass index (BMI) or waist-to-hip ratio (WHR) predicts abnormal overnight OXI remains unknown.Methods: We performed a retrospective cross-sectional study of 393 men seen in the Executive Health Program at Mayo Clinic in Rochester, Minnesota who underwent ambulatory overnight OXI ordered by preventive medicine physicians between January 1, 2004 through December 31, 2010. We compared participant/spouse-reported symptoms (sleepiness, snoring), physician indications for OXI (obesity, fatigue), Epworth Sleepiness Scale scores, anthropomorphic measurements (WHR, BMI), and comorbid medical conditions (hypertension, diabetes) with OXI results.Results: 295 of the 393 men who completed OXI had abnormal results. During multivariate analysis, the strongest independent predictor of abnormal OXI for men was WHR (≥1.0, OR = 5.59) followed by BMI (≥30.0 kg/m2, OR = 2.75), age (≥55 yrs, OR = 2.06), and the presence of snoring (OR = 1.91, P < 0.05 for all). A strong association was observed between WHR and abnormal OXI in obese (BMI ≥ 30.0 kg/m2, OR = 6.28) and non-obese (BMI < 29.9 kg/m2, OR = 6.42, P < 0.01 for both) men. Furthermore, 88 men with abnormal OXI underwent polysomnography with 91% being subsequently diagnosed with OSA.Conclusions: In ambulatory, predominantly middle-aged men undergoing preventive services evaluation many physician indications for OXI were not predictors of abnormal results; however, WHR strongly predicted abnormal OXI in obese and non-obese men. As such, we suggest middle-aged men who snore and have a WHR ≥1.0 should be directly referred to a sleep clinic for polysomnography.

126 BRUE and evaluation of higher-risk infants with overnight oximetry

Primary Subject area Hospital Paediatrics Background BRUE (Brief resolved unexplained event) is a worrisome event for parents. Investigation guidelines for infants 2 months and older have been published, but an evaluation framework for higher-risk infants is still evolving. Objectives The goal of this study is to determine if an overnight oximetry for patients presenting with BRUE under the age of the 2 months would help to target patients at higher risk of recurrent BRUE. The secondary goals are to evaluate the characteristics of those infants, the rate of recurrence of BRUE and to evaluate the effectiveness of other investigations. Design/Methods This was an observational retrospective study of infants presenting with BRUE between the age of 7 days and 60 days between January 1 2010 and October 1 of 2018. Patients were selected if they matched the definition of BRUE defined by the American Academy of Pediatrics in 2016. Patient demographics and antecedents, characteristics of the events, investigations results, recurrence of BRUE, and hospitalizations until the age of 1 year were recorded. Results 103 patients presented with BRUE under the age of 2 months. Of those, 63 (61.2%) were boys. Only four (3.9%) had a recurrence of BRUE. The mean corrected age at the presentation was 20.7 days. Thirty-three (32%) infants had an overnight oximetry; of those 19 (18.4%) had an abnormal result. An abnormal overnight oximetry result was associated with a lower risk of recurrent BRUE (0%) compared to infants without an oximetry (4.3%) or with a negative result (7.1%) (p=0.6195). 68.4% of patients with an abnormal overnight oximetry had received medical treatment (caffeine, oxygen or anti-acid), which was significantly higher than those with normal overnight oximetry (14.3%) or no oximetry (9.4%) (p < 0.0001). There was an association between male sex and abnormal overnight oximetry (p=0.0137). No other investigation was able to predict a higher risk of recurrent BRUE among those evaluated. Conclusion In our cohort, boys were more frequently affected and had a higher rate of abnormal overnight oximetry. One hypothesis is that BRUE under 2 months of age might be a presentation mode for immature respiratory control and boys might be at higher risk for such events. Even though an abnormal result was present in 18.4% of the overnight oximetry, this investigation was not able to identify infants at higher risk of recurrent BRUE. This could be partly explained by the fact that a recurrent BRUE is a rare event and that a majority of patients with abnormal overnight oximetry were treated medically, which might have prevented recurrence.

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

BackgroundThere 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.MethodAdults 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.ResultsOf 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.ConclusionA 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 numberNCT02513836.

Development of a pediatric obstructive sleep apnea triage algorithm

Introduction Diagnosis and treatment of obstructive sleep apnea (OSA) in children is often delayed due to the high prevalence and limited physician and sleep testing resources. As a result, children may be referred to multiple specialties, such as pediatric sleep medicine and pediatric otolaryngology, resulting in long waitlists. Method We used data from our pediatric OSA clinic to identify predictors of tonsillectomy and/or adenoidectomy (AT). Before being seen in the clinic, parents completed the Pediatric Sleep Questionnaire (PSQ) and screening questionnaires for restless leg syndrome (RLS), nasal rhinitis, and gastroesophageal reflux disease (GERD). Tonsil size data were obtained from patient charts and graded using the Brodsky-five grade scale. Children completed an overnight oximetry study before being seen in the clinic, and a McGill oximetry score (MOS) was assigned based on the number and depth of oxygen desaturations. Logistic regression, controlling for otolaryngology physician, was used to identify significant predictors of AT. Three triage algorithms were subsequently generated based on the univariate and multivariate results to predict AT. Results From the OSA cohort, there were 469 eligible children (47% female, mean age = 8.19 years, SD = 3.59), with 89% of children reported snoring. Significant predictors of AT in univariate analysis included tonsil size and four PSQ questions, (1) struggles to breathe at night, (2) apneas, (3) daytime mouth breathing, and (4) AM dry mouth. The first triage algorithm, only using the four PSQ questions, had an odds ratio (OR) of 4.02 for predicting AT (sensitivity = 0.28, specificity = 0.91). Using only tonsil size, the second algorithm had an OR to predict AT of 9.11 (sensitivity = 0.72, specificity = 0.78). The third algorithm, where MOS was used to stratify risk for AT among those children with 2+ tonsils, had the same OR, sensitivity, and specificity as the tonsil-only algorithm. Conclusion Tonsil size was the strongest predictor of AT, while oximetry helped stratify individual risk for AT. We recommend that referral letters for snoring children include graded tonsil size to aid in the triage based on our findings. Children with 2+ tonsil sizes should be triaged to otolaryngology, while the remainder should be referred to a pediatric sleep specialist. Graphical abstract

Long-term oxygen therapy in children with sickle cell disease and hypoxaemia

ObjectiveTo evaluate the acceptability and safety profile of nocturnal long-term oxygen therapy (LTOT) in children with sickle cell disease (SCD) and chronic hypoxaemia.DesignRetrospective cohort study.Patients, setting and interventionChildren with SCD who started LTOT from 2014 to early 2019 in two tertiary hospitals in London, UK were retrospectively enrolled. Patients who started disease-modifying therapies <12 months before LTOT or while on LTOT were excluded.Main outcome measuresMinor and major adverse events during LTOT were reported. Laboratory and clinical data, transcranial Doppler (TCD) scans and overnight oximetry studies performed at steady state within 12 months before and after starting LTOT were compared.ResultsNineteen children (10 males; median age 12 years, range 6–15) were included. Nearly half of them (9/19; 47%) were on hydroxyurea at baseline. No child discontinued LTOT because of intolerance or poor adherence. No major adverse events were reported. Laboratory data did not show significant changes in haemoglobin and reticulocyte count after 1 year of follow-up. No statistically significant change in the incidence of vaso-occlusive pain events was noted (median annual rate from 0.5 to 0 episode per patient/year; p=0.062). Overnight oximetry tests performed while on LTOT showed improvements in all oxygen saturation parameters (mean overnight and nadir SpO2, % of time spent with SpO2 <90%) compared with the baseline.ConclusionLTOT is a safe and feasible treatment option for children with SCD and chronic hypoxaemia.