Validation of the Apnealink Air for diagnosis of obstructive sleep apnoea (OSA) in pregnant women in early-mid gestation.

PURPOSE: The detection of obstructive sleep apnoea (OSA) in pregnant women in early-mid gestation is logistically difficult. Accurate alternates to polysomnography (PSG) in early pregnancy are not well identified. We compared the agreement between Apnealink Air (AL) and existing screening questionnaires to PSG in pregnant women ≤ 24-week gestation. METHODS: Pregnant women (≤ 24-week gestation) underwent AL at home plus attended PSG in any order, completed within 7 days where practicable. AL was manually scored (AL(M)) and automatically scored (AL(A)). An apnoea-hypopnea index (AHI) ≥ 5 was considered diagnostic of OSA and an AHI ≥ 15 considered at least moderate OSA. Diagnostic analysis was undertaken (sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV)) by generating receiver operating characteristic (ROC) curves and an area under the curve (AUC) (95% CI). Bland-Altman plots were used to plot agreement. Screening questionnaires (Epworth sleepiness score (ESS), STOP-BANG, calculated pregnancy-specific screening tool) were compared to PSG. RESULTS: A total of 49 participants successfully completed both tests at around 14-weeks gestation (IQR 12.9, 17.1). The time interval between AL and PSG was a median of 2 days (IQR 1, 5 (range 1-11)). A total of 14 (29%) participants had OSA. The median AHI of AL(A) (3.1(IQR 0.85,4.6)) and AL(M) (IQR2.4(0.65,4.8)) did not differ from PSG (1.7(IQR1.0,6.1)). AL(A) and AL(M) compared to PSG demonstrated diagnostic test accuracy (area under curve (ROC)) of 0.94(95% CI 0.87-1.0) and 0.92(95% CI 0.85-1.0) respectively. Apnealink Air outperformed screening questionnaires tested. CONCLUSION: The findings suggest that Apnealink may provide a substitute to attended PSG identification of OSA in pregnant women in early-mid gestation using both manual and auto-scoring methods.

Validation of self-applied unattended polysomnography using Somte V2 PSG (Somte) for diagnosis of obstructive sleep apnoea (OSA) in pregnant women in early to mid-gestation.

PURPOSE: Polysomnography (PSG) may be completed in the home environment (unattended), and when self-applied, allow the collection of data with minimal healthcare worker intervention. Self-applied, unattended PSG in the home environment using Somte PSG V2 (Somte) has not been validated in pregnant women in early to mid-gestation. We undertook a study to evaluate the accuracy of Somte compared to attended PSG. The agreement between apnoea hypopnea index (AHI) and respiratory disturbance index (RDI) scores in Somte and PSG in early to mid-gestation were assessed. METHODS: Pregnant women (≤ 24 weeks gestation) were scheduled for PSG and Somte within a 7-day window, in any order. Somte were self-applied and completed in the home. Somte were scored blinded to PSG result. AHI was the primary outcome of interest, though an AHI ≥ 5 or RDI ≥ 5 on PSG was considered diagnostic of Obstructive Sleep Apnoea (OSA). AHI, RDI, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) was calculated and receiver operating characteristic (ROC) curves were produced. Bland-Altman plots were used to determine agreement. Technical issues occurring during tests were explored. RESULTS: Twenty-four participants successfully completed both tests between March 2021 and January 2023. PSG were completed at around 14.1 weeks' gestation (IQR 13.4, 15.7). The time interval between Somte and PSG was a median of 4 days (IQR 2, 7 (range 1-12)). Five (20.8%) women had OSA on PSG at AHI ≥ 5 and 10 (41.6%) women had OSA on PSG at RDI ≥ 5. Somte and PSG did not differ in the measurement of AHI ((1.8, 1.6, p = 0.09) or RDI (3.3, 3.5), p = 0.73). At AHI ≥ 5, diagnostic test accuracy (area under the ROC curve) of Somte was 0.94, sensitivity 80.0%, specificity 94.7%, PPV and NPV were 80.0% and 94.7% respectively. At RDI ≥ 5, diagnostic test accuracy (area under the ROC curve) was 0.95, sensitivity 60.0%, specificity 93.0% and PPV and NPV were 85.7% and 76.4% respectively. The confidence limits of Bland-Altman plots were 6.37 to - 8.89 at cut off AHI ≥ 5 and 8.89 to - 10.43 at cut off RDI ≥ 5. Somte failed to start in four tests. Technical issues were reported in both Somte (n = 13, 54.2%) and PSG (n = 6, 25.0%). CONCLUSION: Self-applied, unattended Somte may provide an acceptable substitute to attended PSG in the identification of OSA in pregnant women in early to mid-gestation in this small sample but may fail to detect cases of OSA, particularly when using RDI as the diagnostic marker.

How many hours do you sleep? A comparison of subjective and objective sleep duration measures in a sample of insomnia patients and good sleepers.

Our objective was to assess the agreement and linear relationships amongst multiple measures of sleep duration in a sample of patients with insomnia disorder and good sleeper controls. We retrospectively analysed data from 123 patients with insomnia disorder and 123 age- and gender-matched good sleeper controls who completed a simple subjective habitual sleep duration question (Pittsburgh Sleep Quality Index), a sleep diary (5-14 days), 2 nights of polysomnography, and two corresponding morning subjective estimates of sleep duration. Descriptive statistics, linear regression analyses and Bland-Altman plots were used to describe the relationship and (dis)agreement between sleep duration measures. Relationships between polysomnography and the simple question as well as between polysomnography and sleep diary were weak to non-existent. Subjective measures and polysomnography did not agree. Sleep duration measured with the Pittsburgh Sleep Quality Index or sleep diary was about 2 hr above or up to 4 hr below polysomnography-measured sleep duration. Patients with insomnia disorder, on average, reported shorter sleep duration compared with polysomnography, while good sleeper controls, on average, reported longer sleep duration compared with polysomnography. The results suggest that subjective and objective measures apparently capture different aspects of sleep, even when nominally addressing the same value (sleep duration). They disagree in both patients with insomnia disorder and good sleeper controls, but in different directions. Studies assessing sleep duration should take into account both the investigated population and the assessment method when interpreting results. Future studies should continue to investigate possible psychological and physiological correlates of sleep (mis)perception.

Does obstructive sleep apnea increase the risk of cancer and cancer mortality in combined community-based cohorts?

Obstructive sleep apnea (OSA) has been linked to cancer in several clinical and community-based cohorts. The effect in community-based studies free of clinical referral bias needs to be replicated. In this observational prospective cohort study, we pooled data from three community-based prospective cohorts (Uppsala Sleep and Health in Men cohort [UMEN]; Sleep and health in women [SHE]; Men Androgen Inflammation Lifestyle Environment and Stress Cohort [MAILES]; nTotal = 1467). All cohorts had objective data on obstructive sleep apnea and registry linkage data on cancer and cancer mortality. Analyses for different obstructive sleep apnea measures (apnea-hypopnea index [AHI], oxygen desaturation index [ODI], and minimal saturation) as risk factors for cancer incidence (all cancers) were performed using Cox proportional hazards models (follow-up 5-16 years). We did not find an overall increased risk of cancer after adjustment for age, sex, and BMI (HRAHI [95% CI] = 1.00 [0.98; 1.01] and HRODI [95% CI] = 0.99 [0.97; 1.01]). Stratifying by daytime sleepiness did not influence the association. Cancer mortality was not significantly associated with obstructive sleep apnea. Taken together, we did not observe an overall increased risk of cancer or cancer mortality in relation to obstructive sleep apnea, however, our confidence limits remain wide for important diagnostic categories of sleep apnea severity. The relationship between obstructive sleep apnea and cancer needs further investigation in a comprehensive multi-cohort approach with greater statistical precision. For future studies we may need to find and then combine every community-based cohort study that can provide a definitive answer to the question on the risk of cancer from obstructive sleep apnea in the general population.

Armodafinil to reduce the sleepiness related side-effects of sleep restriction therapy being used to treat insomnia disorder: An open label clinical trial pilot study compared with historical controls.

Sleep restriction therapy (SRT) is an effective stand-alone behavioural intervention for insomnia disorder. However, its daytime side effects, particularly sleepiness, may be troubling for patients and/or may be a necessary part of the patient's treatment journey. This pilot trial aims to explore the potential benefit of armodafinil, a wakefulness promoter. Patients were treated with SRT with open label adjunctive armodafinil (150 mg/day). Thirty-three patients from previous studies that have undergone exactly the same SRT intervention acted as controls. The primary outcome measure was the insomnia severity index (ISI), and secondary outcomes were the Epworth sleepiness scale, sleep restriction adherence scale (SRAS), and safety from baseline through to 12 weeks. We recruited 25 patients into the trial. Data for the primary end point (ISI at 12 weeks) was available for 20 of the participants. The baseline insomnia severity index was 20.2 (SD 3.3) and decreased to 9.1 (SE 1.1), with no change, to 10.2 and 11.2 at weeks 6 and 12 respectively (all p > 0.05 compared with baseline). The insomnia severity index values for armodafinil patients were statistically inferior to historical controls at the primary time point of 12 weeks (11.2 vs. 6.7, p < 0.01). Sleep restriction therapy plus armodafinil treatment was associated with frequent minor side effects but was generally safe and acceptable to patients. Sleep restriction therapy was associated with a robust clinical response in the insomnia severity index values for insomnia patients. Based upon historical control data, armodafinil does not appear to have beneficial adjunctive effects in addition to sleep restriction therapy alone.

Safety of higher doses of melatonin in adults: A systematic review and meta-analysis.

Melatonin is commonly used for sleep and jetlag at low doses. However, there is less documentation on the safety of higher doses, which are being increasingly used for a wide variety of conditions, including more recently COVID-19 prevention and treatment. The aim of this review was to investigate the safety of higher doses of melatonin in adults. Medline, Scopus, Embase and PsycINFO databases from inception until December 2019 with convenience searches until October 2020. Randomised controlled trials investigating high-dose melatonin (≥10 mg) in human adults over 30 years of age were included. Two investigators independently abstracted articles using PRISMA guidelines. Risk of bias was assessed by a committee of three investigators. 79 studies were identified with a total of 3861 participants. Studies included a large range of medical conditions. The meta-analysis was pooled data using a random effects model. The outcomes examined were the number of adverse events (AEs), serious adverse events (SAEs) and withdrawals due to AEs. A total of 29 studies (37%) made no mention of the presence or absence of AEs. Overall, only four studies met the pre-specified low risk of bias criteria for meta-analysis. In that small subset, melatonin did not cause a detectable increase in SAEs (Rate Ratio = 0.88 [0.52, 1.50], p = .64) or withdrawals due to AEs (0.93 [0.24, 3.56], p = .92), but did appear to increase the risk of AEs such as drowsiness, headache and dizziness (1.40 [1.15, 1.69], p < .001). Overall, there has been limited AE reporting from high-dose melatonin studies. Based on this limited evidence, melatonin appears to have a good safety profile. Better safety reporting in future long-term trials is needed to confirm this as our confidence limits were very wide due to the paucity of suitable data.

Predictors of weight loss in obese patients with obstructive sleep apnea.

PURPOSE: Consistent predictors of weight loss outcomes with very low-energy diets (VLEDs) in obstructive sleep apnea (OSA) have not been identified. This study aimed to identify variables predictive of weight loss success in obese patients with OSA undertaking an intensive weight loss programme. METHODS: We analysed biological, psychological, and behavioural variables as potential predictors of weight loss in obese patients with OSA after a 2-month VLED followed by one of two 10-month weight loss maintenance diets. Actigraphy, in-lab polysomnography, urinary catecholamines, and various psychological and behavioural variables were measured at baseline, 2, and 12 months. Spearman's correlations analysed baseline variables with 2-month weight loss, and 2-month variables with 2-12 month-weight change. RESULTS: Forty-two patients completed the VLED and thirty-eight completed the maintenance diets. Actigraphy data revealed that late bedtime (rs = - 0.45, p = < 0.01) was correlated with 2-month weight loss. The change in the time that participants got out of bed (rise-time) from baseline to two months was also correlated with 2-month weight loss (rs = 0.36, p = 0.03). The Impact of Weight on Quality of Life-Lite questionnaire (IWQOL) Public Distress domain (rs = - 0.54, p = < 0.01) and total (rs = - 0.38, p = 0.02) scores were correlated with weight loss maintenance from 2 to 12 months. CONCLUSIONS: Results from this small patient sample reveal correlations between actigraphy characteristics and weight loss in obese patients with OSA. We suggest the IWQOL may also be a useful clinical tool to identify OSA patients at risk of weight regain after initial weight loss. CLINICAL TRIAL REGISTRATION: This clinical trial was prospectively registered on 18/02/2013 with the Australia and New Zealand Clinical Trials Registry (ACTRN12613000191796). PUBLIC REGISTRY TITLE: Sleep, Lifestyle, Energy, Eating, Exercise Program for the management of sleep apnea patients indicated for weight loss treatment: A randomised, controlled pilot study. URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=363680.

The Effectiveness of Digital Insomnia Treatment with Adjunctive Wearable Technology: A Pilot Randomized Controlled Trial.

OBJECTIVE: This pilot trial aimed to provide evidence for whether the integration of a wearable device with digital behavioral therapy for insomnia (dBTi) improves treatment outcomes and engagement. PARTICIPANTS AND METHODS: One hundred and twenty-eight participants with insomnia symptoms were randomized to a 3-week dBTi program (SleepFix®) with a wearable device enabling sleep data synchronization (dBTi+wearable group; n = 62) or dBTi alone (n = 66). Participants completed the Insomnia Severity Index (ISI) and modified Pittsburgh Sleep Quality Index (PSQI) parameters: wake-after-sleep-onset (WASO), sleep-onset-latency (SOL), and total sleep time (TST) at baseline and weeks 1, 2, 3, and primary endpoint of week 6 and follow-up at 12 weeks. Engagement was measured by the number of daily sleep diaries logged in the app. RESULTS: There was no difference in ISI change scores between the groups from pre- to post-treatment (Cohen's d= 0.7, p= .061). The dBTi+wearable group showed greater improvements in WASO (d= 0.8, p = .005) and TST (d= 0.3, p= .049) compared to the dBTi group. Significantly greater engagement (sleep diary entries) was observed in the dBTi+wearable group (mean = 22.4, SD = 10.0) compared to the dBTi group (mean = 14.1, SD = 14.2) (p = .010). CONCLUSIONS: This pilot trial found that integration of wearable device with a digital insomnia therapy enhanced user engagement and led to improvements in sleep parameters compared to dBTi alone. These findings suggest that adjunctive wearable technologies may improve digital insomnia therapy effectiveness.

Analyzing Unnecessary Imaging for Low Back Pain in Nebraska from a Statewide Health Information Exchange.

Excessive amounts of resources in healthcare are wasted due to duplicated or unnecessary health screenings, especially in the diagnosis of low back pain (LBP). Research shows that two-thirds of people will present with LBP at some point throughout their lifetime, but 20-50% of high-tech imaging procedures fail to provide information that improves the patient's condition, representing unnecessary services. The purpose of this study was to evaluate the existence of unnecessary imaging for low back pain throughout healthcare systems in Nebraska based on what was documented in the electronic health record. This study was a retrospective electronic health record analysis of a limited data set focused on procedures related to imaging for LBP extracted from Nebraska Health Information Exchange (HIE) managed by CyncHealth. The sample included 937 patient records with a diagnosis of LBP who received imaging in the state of Nebraska and whose health record was recorded in the Nebraska HIE. To determine necessity, records were categorized in three areas including necessary imaging, likely wasteful imaging, or wasteful imaging based on the criteria from the "First, Do No Harm" study conducted by the Washington Health Alliance. Results revealed a total of 51% of low back pain imaging considered wasteful, 35% likely wasteful, and 14% necessary. Based on these results, further research is warranted to determine specific demographics related to necessary, likely wasteful, and wasteful imaging and the purpose for performing these expensive imaging procedures.

Sleep EEG microstructure is associated with neurobehavioural impairment after extended wakefulness in obstructive sleep apnea.

PURPOSE: Using quantitative EEG (qEEG) analysis, we investigated sleep EEG microstructure as correlates of neurobehavioural performance after 24 h of extended wakefulness in untreated OSA. METHODS: Eight male OSA patients underwent overnight polysomnography (PSG) at baseline followed by 40 h awake with repeated performance testing (psychomotor vigilance task [PVT] and AusEd driving simulator). EEG slowing during REM and spindle density during NREM sleep were calculated using power spectral analysis and a spindle detection algorithm at frontal and central electrode sites. Correlations between sleep EEG microstructure measures and performance after 24-h awake were assessed. RESULTS: Greater EEG slowing during REM sleep was associated with slower PVT reaction times (rho = - 0.79, p = 0.02), more PVT lapses (rho = 0.87, p = 0.005) and more AusEd crashes (rho = 0.73, p = 0.04). Decreased spindle density in NREM sleep was also associated with slower PVT reaction times (rho = 0.89, p = 0.007). Traditional PSG measures of disease severity were not consistent correlates of neurobehavioural performance in OSA. CONCLUSIONS: Sleep EEG microstructure measures recorded during routine PSG are associated with impaired vigilance in OSA patients after sleep deprivation. SIGNIFICANCE: Quantitative brain oscillatory (or EEG)-based measures of sleep may better reflect the deleterious effects of untreated OSA than traditional PSG metrics in at-risk individuals. Trial Registration ACTRN12606000066583.

Melatonin for rapid eye movement sleep behavior disorder in Parkinson's disease: A randomised controlled trial.

BACKGROUND: Melatonin may reduce REM-sleep behavior disorder (RBD) symptoms in Parkinson's disease (PD), though robust clinical trials are lacking. OBJECTIVE: To assess the efficacy of prolonged-release (PR) melatonin for RBD in PD. METHODS: Randomized, double-blind, placebo-controlled, parallel-group trial with an 8-week intervention and 4-week observation pre- and postintervention (ACTRN12613000648729). Thirty PD patients with rapid eye movement sleep behavior disorder were randomized to 4 mg of prolonged-release melatonin (Circadin) or matched placebo, ingested orally once-daily before bedtime. Primary outcome was the aggregate of rapid eye movement sleep behavior disorder incidents averaged over weeks 5 to 8 of treatment captured by a weekly diary. Data were included in a mixed-model analysis of variance (n = 15 per group). RESULTS: No differences between groups at the primary endpoint (3.4 events/week melatonin vs. 3.6 placebo; difference, 0.2; 95% confidence interval = -3.2 to 3.6; P = 0.92). Adverse events included mild headaches, fatigue, and morning sleepiness (n = 4 melatonin; n = 5 placebo). CONCLUSION: Prolonged-release melatonin 4 mg did not reduce rapid eye movement sleep behavior disorder in PD. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Impact factor rankings for sleep research journals between 2005 and 2018.

Impact factors and ranking lists of research journals are very often used to judge our career achievements and progression by employers and granting bodies. However, a comprehensive list for the interdisciplinary field of sleep research does not currently exist because our journals tend to be placed into discipline-specific lists that do not cope well with our historic interdisciplinarity, which embraces many core disciplines. We aimed to build a ranking list specifically for sleep research journals based on the journal impact factor and the google scholar H5 indices. We then searched for all sleep journals given an impact factor by Thomson Reuters from 2005 to 2018 and all journals given a current H5 index by Google Scholar. We provide a ranking list specifically for sleep journals that might be useful for researchers to cite when providing context in their applications for employment, promotion and funding.

Dose-dependent effects of continuous positive airway pressure for sleep apnea on weight or metabolic function: Individual patient-level clinical trial meta-analysis.

Therapeutic-continuous positive airway pressure seems to increase weight compared with placebo-continuous positive airway pressure. It is not known whether weight gain with therapeutic-continuous positive airway pressure dose is dependent or whether it causes metabolic dysfunction. Data synthesis of three randomised placebo-continuous positive airway pressure-controlled trials (2-3 months) was performed to test whether there is a dose-dependent effect of continuous positive airway pressure on weight. Fasting glucose, insulin, insulin resistance (homeostatic model assessment), lipids and visceral abdominal fat were also tested to determine any effect on metabolic function. Mixed-model analysis of variance was used to quantify these effects. One-hundred and twenty-eight patients were analysed. Overall there was a small increase in weight with therapeutic-continuous positive airway pressure use compared with placebo-continuous positive airway pressure (difference: 1.17 kg; 0.37-1.97, p = 0.005), which was greater with high-use therapeutic-continuous positive airway pressure compared with high-use placebo-continuous positive airway pressure (1.45 kg; 0.10-2.80, p = 0.04). Continuous positive airway pressure use as a continuous variable was also significantly associated with weight change in continuous positive airway pressure users (0.30 kg hr-1  night-1 ; 0.04-0.56, p = 0.001), but not in placebo users (0.04 kg hr-1  night-1 ; -0.22 to 0.26, p = 0.76). Neither therapeutic-continuous positive airway pressure nor the dose of therapeutic-continuous positive airway pressure caused any changes to metabolic outcomes. The weight gain effects of medium-term therapeutic-continuous positive airway pressure appear modest and are not accompanied by any adverse metabolic effects.

Intra-individual stability of NREM sleep quantitative EEG measures in obstructive sleep apnea.

Electroencephalography is collected routinely during clinical polysomnography, but is often utilised to simply determine sleep time to calculate apnea-hypopnea indices. Quantitative analysis of these data (quantitative electroencephalogram) may provide trait-like information to predict patient vulnerability to sleepiness. Measurements of trait-like characteristics need to have high test-retest reliability. We aimed to investigate the intra-individual stability of slow-wave (delta power) and spindle frequency (sigma power) activity during non-rapid eye movement sleep in patients with obstructive sleep apnea. We recorded sleep electroencephalograms during two overnight polysomnographic recordings in 61 patients with obstructive sleep apnea (median days between studies 47, inter-quartile range 53). Electroencephalograms recorded at C3-M2 derivation were quantitatively analysed using power spectral analysis following artefact removal. Relative delta (0.5-4.5 Hz) and sigma (12-15 Hz) power during non-rapid eye movement sleep were calculated. Intra-class correlation coefficients and Bland-Altman plots were used to assess agreement between nights. Intra-class correlation coefficients demonstrated good-to-excellent agreement in the delta and sigma frequencies between nights (intra-class correlation coefficients: 0.84, 0.89, respectively). Bland-Altman analysis of delta power showed a mean difference close to zero (-0.4, 95% limits of agreement -9.4, 8.7) and no heteroscedasticity with increasing power. Sigma power demonstrated heteroscedasticity, with reduced stability as sigma power increased. The mean difference of sigma power between nights was close to zero (0.1, 95% limits -1.6, 1.8). We have demonstrated the stability of slow-wave and spindle frequency electroencephalograms during non-rapid eye movement sleep within patients with obstructive sleep apnea. The electroencephalogram profile during non-rapid eye movement sleep may be a useful biomarker for predicting vulnerability to daytime impairment in obstructive sleep apnea and responsiveness to treatment.

Does Armodafinil Improve Driving Task Performance and Weight Loss in Sleep Apnea? A Randomized Trial.

RATIONALE: Patients with obstructive sleep apnea (OSA) unable to tolerate standard treatments have few alternatives. They may benefit from weight loss, but the major symptom of daytime performance impairment may remain during weight loss programs. OBJECTIVES: We hypothesized that wakefulness-promoter armodafinil would improve driving task performance over placebo in patients undergoing weight loss. METHODS: This was a placebo-controlled, double-blind, randomized trial of armodafinil versus placebo daily for 6 months in patients who were also randomized to one of two diets for 6 months with follow-up at 1 year in overweight, adult, patients with OSA who had rejected standard treatment and suffered daytime sleepiness. MEASUREMENTS AND MAIN RESULTS: Primary outcome was change in steering deviation in the final 30 minutes of a 90-minute afternoon driving task (AusED) at 6 months. Secondary outcomes were Epworth Sleepiness Scale, Functional Outcomes of Sleep Questionnaire, and fat mass measured by dual-emission X-ray absorptiometry. Armodafinil improved driving task performance over placebo at 3 months (12.9 cm; 95% confidence interval, 4.1-21.7; P = 0.004), but not the primary time point of 6 months (5.5 cm; 95% confidence interval, -3.3 to 14.3; P = 0.223). Patients on armodafinil lost 2.4 kg more fat than those on placebo at 6 months (95% confidence interval, 0.9-4.0; P = 0.002). Other secondary outcomes were not significantly improved. CONCLUSIONS: Armodafinil did not improve driving task performance at the primary endpoint of 6 months. Armodafinil might be a useful adjunctive to weight loss in patients with OSA rejecting conventional treatments but this needs to be directly tested in a specifically designed, properly powered clinical trial. Clinical trial registered with Australian and New Zealand Clinical Trials Registry (ACTRN 12611000847910).

Parsing the craniofacial phenotype: effect of weight change in an obstructive sleep apnoea population.

PURPOSE: Craniofacial structure is an important risk factor in the development of obstructive sleep apnoea. Most craniofacial imaging methods are not feasible for large-scale studies or the clinic. Craniofacial photography is a high-throughput technique for facial phenotyping; however, derived measurements are a composite of skeletal and soft tissue craniofacial information. Weight change is a paradigm to help determine which facial measurements most relate to regional soft tissue (i.e. change with weight) versus skeletal structure (i.e. stable with weight changes). We aimed to assess the association between weight change and changes in key facial measurements from facial photography. METHODS: Calibrated frontal and profile photographs were taken of participants in weight loss studies (N = 106). Univariate linear regression was used to assess whether weight change explained changes in facial dimensions. RESULTS: Patients lost 11.7 ± 10.8 kg body weight and 2.0 ± 2.0 cm of neck circumference. Weight changes influenced face width (r = 0.3, p < 0.001), mandibular width (r = 0.4, p < 0.001) and cervicomental angle (r = 0.3, p = 0.001). Facial angles, facial heights and mandibular length were not influenced by weight change. CONCLUSIONS: A weight loss paradigm suggests that face and mandibular width and cervicomental angle most strongly reflect regional adiposity. Facial angles and heights are insensitive to weight change and could be more representative of craniofacial skeletal structure. This study informs the interpretation of facial phenotype assessed by this craniofacial photographic method which can be applied to future studies of craniofacial phenotype in OSA.

No association between sleep apnoea and macular telangiectasia type 2 and its markers of severity and progression: a case-control study and retrospective cohort study.

IMPORTANCE: Idiopathic Macular Telangiectasia Type 2 (MacTel) is an uncommon, progressive retinal disease usually affecting both eyes. Currently there is no know treatment however with similar comorbidities to Obstructive Sleep Apnoea (OSA) there is plausibility of an association which may accelerate disease progression. BACKGROUND: To identify an association between MacTel and OSA and whether OSA may result in increased disease progression. DESIGN: Matched case-control study and retrospective cohort analysis. PARTICIPANTS: Fifty-seven patients with MacTel and 165 matched controls from the Busselton Health Study. METHODS: MacTel participants were matched based on age, gender and body mass index (BMI) (and where possible hypertension and diabetes) on a 3:1 ratio with controls from the Busselton Health Study. Participants undertook a sleep questionnaire using a previously validated questionnaire. In a subset sleep apnoea severity was objectively measured via overnight ambulatory polygraphy (30 cases and 83 matched controls; ApneaLink device; ResMed, Sydney, Australia). In a retrospective analysis of the suspected MacTel cases we assessed whether major markers of OSA severity and MacTel progression were associated. MAIN OUTCOME MEASURES: Apnoea Hypopnea Index along with key markers of MacTel progression. RESULTS: MacTel patients did not have a higher risk of sleep apnoea when compared to age, sex and BMI -matched controls (mean ± SD Apnoea hypopnea index [AHI] cases 9.6 ± 14.7 vs. controls 9.7 ± 10.8, P = 0.95). No markers of disease progression in the cases were associated with any marker of OSA severity. CONCLUSIONS AND RELEVANCE: Sleep apnoea does not increase the risk or accelerate the progression of MacTel.

Maintenance diets following rapid weight loss in obstructive sleep apnea: a pilot 1-year clinical trial.

Very low energy diets (VLED) appear to be the most efficacious dietary-based obesity reduction treatments in obstructive sleep apnea (OSA); however, effective weight loss maintenance strategies remain untested in this condition. Our study aimed to assess the feasibility, tolerability and efficacy of two common maintenance diets during a 10-month follow-up period after rapid weight loss using a 2-month VLED. In this two-arm, single-centre, open-label pilot trial, obese adult OSA patients received a 2-month VLED before being allocated to either the Australian Guide to Healthy Eating diet (AGHE) or a low glycaemic index high-protein diet (LGHP). Outcomes were measured at 0, 2 and 12 months. We recruited 44 patients [113.1 ± 19.5 kg, body mass index (BMI): 37.2 ± 5.6 kg m-2 , 49.3 ± 9.2 years, 12 females]. Twenty-four patients were on continuous positive airway pressure (CPAP) or mandibular advancement splint (MAS) therapy for OSA. Forty-two patients completed the VLED. The primary outcome of waist circumference was reduced by 10.6 cm at 2 months [95% confidence interval (CI): 9.2-12.1], and patients lost 12.9 kg in total weight (95% CI: 11.2-14.6). There were small but statistically significant regains in waist circumference between 2 and 12 months [AGHE = 3.5 cm (1.3-5.6) and LGHP = 2.8 cm (0.6-5.0]. Other outcomes followed a similar pattern of change. After weight loss with a 2-month VLED in obese patients with OSA, a structured weight loss maintenance programme incorporating commonly used diets was feasible, tolerable and efficacious for 10 months. This programme may be deployed easily within sleep clinics; however, future research should first test its translation within general clinical practice.