Bronchiectasis among Indigenous adults in the Top End of the Northern Territory, 2011-2020: a retrospective cohort study.

OBJECTIVES: To assess the prevalence of bronchiectasis among Aboriginal and Torres Strait Islander (Indigenous) adults in the Top End of the Northern Territory, and mortality among Indigenous adults with bronchiectasis. STUDY DESIGN: Retrospective cohort study. SETTING, PARTICIPANTS: Aboriginal and Torres Strait Islander adults (18 years or older) living in the Top End Health Service region of the NT in whom bronchiectasis was confirmed by chest computed tomography (CT) during 1 January 2011 - 31 December 2020. MAIN OUTCOME MEASURES: Prevalence of bronchiectasis, and all-cause mortality among Indigenous adults with CT-confirmed bronchiectasis - overall, by sex, and by health district - based on 2011 population numbers (census data). RESULTS: A total of 23 722 Indigenous adults lived in the Top End Health Service region in 2011; during 2011-2020, 459 people received chest CT-confirmed diagnoses of bronchiectasis. Their median age was 47.5 years (interquartile range [IQR], 39.9-56.8 years), 254 were women (55.3%), and 425 lived in areas classified as remote (93.0%). The estimated prevalence of bronchiectasis was 19.4 per 1000 residents (20.6 per 1000 women; 18.0 per 1000 men). The age-adjusted prevalence of bronchiectasis was 5.0 (95% CI, 1.4-8.5) cases per 1000 people in the Darwin Urban health area, and 18-36 cases per 1000 people in the three non-urban health areas. By 30 April 2023, 195 people with bronchiectasis had died (42.5%), at a median age of 60.3 years (IQR, 50.3-68.9 years). CONCLUSION: The prevalence of bronchiectasis burden among Indigenous adults in the Top End of the NT is high, but differed by health district, as is all-cause mortality among adults with bronchiectasis. The socio-demographic and other factors that contribute to the high prevalence of bronchiectasis among Indigenous Australians should be investigated so that interventions for reducing its burden can be developed.

Hospital admission rates and related outcomes among adult Aboriginal australians with bronchiectasis - a ten-year retrospective cohort study.

BACKGROUND: This study assessed hospitalisation frequency and related clinical outcomes among adult Aboriginal Australians with bronchiectasis over a ten-year study period. METHOD: This retrospective study included patients aged ≥ 18 years diagnosed with bronchiectasis between 2011 and 2020 in the Top End, Northern Territory of Australia. Hospital admissions restricted to respiratory conditions (International Classification of Diseases (ICD) code J) and relevant clinical parameters were assessed and compared between those with and without hospital admissions. RESULTS: Of the 459 patients diagnosed to have bronchiectasis, 398 (87%) recorded at least one respiratory related (ICD-J code) hospitalisation during the 10-year window. In comparison to patients with a recorded hospitalisation against those without-hospitalised patients were older (median 57 vs 53 years), predominantly females (54 vs 46%), had lower body mass index (23 vs 26 kg/m2) and had greater concurrent presence of chronic obstructive pulmonary disease (COPD) (88 vs 47%), including demonstrating lower spirometry values (forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) (median FVC 49 vs 63% & FEV1 36 vs 55% respectively)). The total hospitalisations accounted for 3,123 admissions (median 4 per patient (IQR 2, 10)), at a median rate of 1 /year (IQR 0.5, 2.2) with a median length of 3 days (IQR 1, 6). Bronchiectasis along with COPD with lower respiratory tract infection (ICD code-J44) was the most common primary diagnosis code, accounting for 56% of presentations and 46% of days in hospital, which was also higher for patients using inhaled corticosteroids (81 vs 52%, p = 0.007). A total of 114 (29%) patients were recorded to have had an ICU admission, with a higher rate, including longer hospital stay among those patients with bronchiectasis and respiratory failure related presentations (32/35, 91%). In multivariate regression model, concurrent presence of COPD or asthma alongside bronchiectasis was associated with shorter times between subsequent hospitalisations (-423 days, p = 0.007 & -119 days, p = 0.02 respectively). CONCLUSION: Hospitalisation rates among adult Aboriginal Australians with bronchiectasis are high. Future interventions are required to explore avenues to reduce the overall morbidity associated with bronchiectasis among Aboriginal Australians.

Establishing a telehealth model addressing paediatric sleep health in remote and rural Northern Territory Australia: Overcoming the distance barrier.

AIM: This study examined the outcomes of a telehealth model for sleep health assessment among Indigenous and non-Indigenous children residing in remote and regional communities at the Top End Northern Territory (NT) of Australia. METHODS: Video telehealth consultation, that included clinical history and relevant physical findings assessed virtually with an interstate paediatric sleep physician was conducted remotely. Polysomnography (PSG) and therapeutic interventions were carried out locally at Darwin, NT. The study participants were children referred between 2015 and 2020. RESULTS: Of the total 812 children referred for sleep assessment, 699 underwent a diagnostic PSG. The majority of patients were female (63%), non-Indigenous (81%) and resided in outer regional areas (88%). Indigenous children were significantly older and resided in remote or very remote locations (22% vs. 10%). Referral patterns differed according to locality and Indigenous status - (non-Indigenous via private (53%), Indigenous via public system (35%)). Receipt of referrals to initial consultation was a median of 16 days and 4 weeks from consult to PSG. Remote children had slightly longer time delay between the referral and initial consult (32 vs. 15 days). Fifty one percent were diagnosed to have OSA, 27% underwent adenotonsillectomy and 2% were prescribed with CPAP therapy. CONCLUSIONS: This study has demonstrated that a telehealth model can be an effective way in overcoming logistical barriers and in providing sleep health services to children in remote and regional Australia. Further innovative efforts are needed to improve the service model and expand the reach for vulnerable children in very remote communities.

Validity of the new 'Top End Sleepiness Scale' against the STOP-Bang tool in predicting obstructive sleep apnoea among Indigenous Australian adults.

BACKGROUND: The validity of the newly developed sleepiness assessment tool, the 'Top End Sleepiness Scale' (TESS), against other established obstructive sleep apnoea (OSA) screening tools has not been evaluated. AIMS: To compare the utility and validity of the culturally safe and clinically relevant subjective daytime sleepiness assessment tool, the 'TESS' was used among Indigenous Australians against STOP-Bang screening tool for predicting OSA in a regional and remote Indigenous Australian cohort. METHODS: The TESS questionnaire, consisting of pictorial representations of six items representing daily activities that would induce daytime sleepiness specific for Indigenous Australians, was assessed for its correlation in predicting moderate to severe OSA according to Apnoea-Hypopnoea Index (AHI, ≥15) against the STOP-Bang screening tool. RESULTS: Eighty Indigenous Australian patients (51% male; mean age 45.1 ± 11.5 years) were included in this study with the majority (n = 70; 88%) having OSA, of which 65 (93%) had an AHI ≥ 15. Area under the curve statistics for overall scores showed no significant difference between TESS or STOP-Bang in the prediction of OSA (P = 0.16). A moderate risk score of TESS (≥3) was superior to STOP-Bang (score 3-4) in sensitivity (84% vs 33%) and specificity (39% vs 30%). The sensitivity for a high-risk score for the STOP-Bang (≥5) was superior to the TESS (≥8; 60% vs 33%), although specificity was comparable (83% vs 91% respectively). CONCLUSIONS: The TESS screening tool could be a useful standalone or could be adopted alongside the STOP-Bang OSA screening tools in the clinical assessment of sleep disorders among Indigenous Australians.

Flexible bronchoscopy indications and outcomes between indigenous and non-indigenous patients in the Northern Territory of Australia.

BACKGROUND: There is sparse evidence in the literature in relation to indications and outcomes among adult indigenous patients requiring a flexible bronchoscopy (FB). In this study, FB indications and outcomes between indigenous and non-indigenous patients were assessed. AIM: To assess the similarities and differences of FB indications and outcomes between indigenous and non-indigenous patients. METHODS: Self-reported indigenous status, resident locality and the primary indication for FB were assessed. The FB procedures details, results of microbiology, cytology and histopathology were compared between indigenous and non-indigenous patients. Chest computed tomography (CT) was also analysed for its relationship to FB outcomes. RESULTS: Of the 403 patients, 111 (28%) were indigenous, and indigenous patients were younger (mean difference 11 years) and had a higher proportion of remote residence (70% vs 13%). Malignancy (40%) and infection (31%) were the most common indications for FB, although indigenous patients reported significantly more haemoptysis (15% vs 9%). No differences were noted in findings of the preceding chest CT scans. For positive microbiology, indigenous patients had a higher presence of Streptococcus pneumoniae (30% vs 9%), while non-indigenous patients had a higher presence of Pseudomonas aeruginosa (43% vs 11%) and mycobacteria (15% vs 4%). There was no significant difference between indigenous and non-indigenous patients for a positive histopathology, particularly for a diagnosis of lung malignancy (58% vs 54%). CONCLUSIONS: This study has demonstrated that adult indigenous patients requiring a FB are significantly younger, tend to reside in remote communities and demonstrate differing microbiology with no significant difference in the diagnostic outcomes for lung malignancy. Ethnic status or remoteness should not preclude indigenous patients to undergo a FB if clinically indicated.

Correlation of spirometry indices to chest radiology in the diagnosis of chronic airway disease among regional and rural Indigenous Australians.

BACKGROUND: The majority of Indigenous Australians reside in non-urban locations, with reduced access to chest radiology such as computed tomography (CT). Spirometry and chest X-ray (CXR) may be used in the absence of CT; however, the correlation of spirometry indices to CT-defined chronic airway diseases (i.e. chronic obstructive pulmonary disease (COPD) and bronchiectasis) compared with CXR among Indigenous people is sparsely reported. AIM: To evaluate spirometry indices against CXR and CT findings among adult Indigenous Australians. METHODS: Indigenous patients who had undergone a spirometry test between 2012 and 2020 and had a CXR or chest CT scan assessed for the presence (+ )/absence (- ) of airway diseases were included in this study. RESULTS: Of 643 patients (57% female, 31% remote/very remote), 364 (57%) had CT and CXR available. Patients who were 'CT- and CXR- ' for airway diseases (48%) recorded a mean FVC, FEV1 and FEV1 /FVC of 61%, 59% and 0.76 compared to 57%, 49% and 0.66 in the 'CT+ and CXR- ' group and 53%, 39% and 0.58 in the 'CT+ and CXR+ ' group. CXR showed sensitivity (44%) and specificity (88%), while spirometry showed 62% and 77% compared to CT. Spirometry demonstrated predominately restrictive impairment among 'CT- and CXR- ' and mixed/obstructive impairment among 'CT+ and CXR- ' and 'CT+ and CXR+ ' groups. CONCLUSION: Indigenous Australians tend to demonstrate restrictive impairment in the absence of radiological evidence of airway disease. However, in the presence of airway disease, combinations of mixed and obstructive impairments were common. Obstructive impairment shows greater sensitivity for identifying COPD than that shown by CXR; however, CXR shows greater specificity. Hence, spirometry in conjunction with chest radiology should be utilised to aid in the assessment of airway diseases in this population.

Comparison of clinical manifestation among Australian Indigenous and non-indigenous patients presenting with pleural effusion.

BACKGROUND: There is sparse evidence in the literature in relation to the nature and causes of pleural effusion among Australian Indigenous population. AIM: To investigate the clinical and demographic characteristics of adult indigenous patients presenting with pleural effusion in the Northern Territory of Australia. METHODS: In this retrospective study, indigenous and non-indigenous adults diagnosed to have pleural effusion over a 2-year study period were included for comparative analysis. RESULTS: Of the 314 patients, 205 (65%) were non-indigenous and 52% were male. In comparison with non-indigenous patients, the indigenous patients were younger (50 years (interquartile range (IQR) 39-60) vs 63 years (IQR 52-72); P < 0.001), female (61% vs 41%; P = 0.001), had a higher prevalence of renal and cardiovascular disease and tended to have exudative effusion (93% vs 76%; P = 0.032). Infections were judged to be the most common cause of effusion in both groups, more so among the indigenous cohort. Effusion secondary to renal disease was higher (13% vs 1%; P < 0.001) among Australian Indigenous patients, but in contrast, malignant effusions were higher (13% vs 4%; P = 0.004) among non-indigenous patients. Length of hospital stay was longer for indigenous patients (P = 0.001), and a greater proportion received renal dialysis (13% vs 1%; P < 0.001). Intensive care unit admission rates were higher with infective aetiology of pleural effusion (82% vs 53% indigenous and 44% vs 39% non-indigenous respectively). Re-presentations to hospital were higher among indigenous patients (46% vs 33%; P = 0.046) and were associated with renal and cardiac disease and malignancy in non-indigenous patients. CONCLUSION: There are significant differences in the way pleural effusion manifests among Australian Indigenous patients. Understanding these differences might facilitate approaches to management and to implementation of strategies to reduce morbidity and mortality in this population.

Obstructive sleep apnoea and adherence to continuous positive airway therapy among Australian women.

BACKGROUND: Clinical characteristics of women with different obstructive sleep apnoea (OSA) severity and adherence to continuous positive airway pressure (CPAP) therapy have not been previously explored. AIMS: To assess OSA prevalence, predictors, clinical and polysomnographic (PSG) characteristics and adherence to CPAP therapy among adult Australian women in a retrospective study. METHODS: All female patients who underwent a diagnostic PSG between 2014 and 2015 were included. CPAP adherence was assessed during the study period between 2018 and 2019 using multiple regression models. RESULTS: Among a total of 591 women included in this study (Aboriginal, n = 86), OSA was diagnosed in 458/591 (78%) patients; mild, moderate and severe OSA was present in 44%, 27% and 29% respectively. Older age, higher BMI and hypertension predicted the presence and severity of OSA. The Epworth Sleepiness Scale (ESS) score was not significantly different with (8 (5, 12)) or without (10 (5, 13)) OSA. PSG showed the rapid eye movement (REM) sleep-associated apnoea-hypopnea index (AHI) was higher with all severity of OSA. Adherence to CPAP therapy was noted in 171 (57%) patients; 47% mild, 57% moderate and 63% with severe OSA respectively. Three multiple regression models (clinical, PSG parameters, OSA severity, combined (clinical and PSG)) showed the combined model had the strongest predictive value and demonstrated that higher ESS and more severe oxygen desaturation were associated with CPAP adherence irrespective of OSA severity. CONCLUSIONS: Older age, higher BMI and the presence of hypertension predicted the presence of OSA. The REM sleep-related AHI was higher. Adherence to CPAP was associated with symptomatic OSA and severe oxygen desaturation.

Comparison and outcomes of emergency department presentations with respiratory disorders among Australian indigenous and non-indigenous patients.

BACKGROUND: There is sparse evidence in the literature assessing emergency department presentation with respiratory disorders among Indigenous patients. The objective of this study was to evaluate the clinical characteristics and outcomes for Indigenous Australians in comparison to non-Indigenous patients presenting to Emergency Department (ED) with respiratory disorders. METHODS: In this study, two non-contiguous one-month study periods during wet (January) and dry (August) season were reported on, and differences in demographics, respiratory diagnosis, hospital admission, length of hospital stay, re-presentation to hospital after discharge and mortality between Australian Indigenous and non-Indigenous patients was assessed. RESULTS: There were a total of 528 respiratory ED presentations, 258 (49%) during wet and 270 (51%) in dry season, from 477 patients (52% female and 40% Indigenous). The majority of ED presentations (84%) were self-initiated, with a difference between Indigenous (80%) and non-Indigenous (88%) presentations. Indigenous presentations recorded a greater proportion of transfers from another healthcare facility compared to non-Indigenous presentations (11% vs. 1%). Less than half of presentations (42%) resulted in admission to the ward with no difference by Indigenous status. Lower respiratory tract infections were the most common cause of presentation (41%), followed by airway exacerbation (31%) which was more commonly seen among Indigenous (34%) than non-Indigenous (28%) presentations. Almost 20% of Indigenous patients reported multiple presentations to ED compared to 1% of non-Indigenous patients, though mortality on follow up did not differ (22% for both). CONCLUSIONS: The results of this study may be an avenue to explore possibilities of implementing programs that may be helpful to reduce preventable ED presentation and recurrent hospitalisations among Indigenous population.

Utility and outcomes among Indigenous and non-Indigenous patients requiring domiciliary oxygen therapy in the regional and rural Australian population.

OBJECTIVE: To evaluate the utility and outcomes for Indigenous and non-Indigenous patients requiring domiciliary oxygen therapy. DESIGN: Retrospective study. SETTING: Patients residing in the regional and rural Top End Health Service region of the Northern Territory of Australia. PARTICIPANTS: Indigenous and non-Indigenous patients prescribed domiciliary oxygen therapy between 2018 and 2020. INTERVENTIONS: Demographics and clinical indication for domiciliary oxygen therapy and mortality were analysed. MAIN OUTCOME MEASURES: Differences between Indigenous patients requiring domiciliary oxygen therapy in comparison with their non-Indigenous counterparts. RESULTS: Of the 199 study participants, the majority were male (51%), non-Indigenous (77%) and urban residents (72%). Overall chronic obstructive pulmonary disease was the most common indication for domiciliary oxygen therapy (51%) followed by palliative intent (22%). Indigenous patients were significantly younger (61 vs 73 years), with a higher proportion of males (62% vs 45%, P = .039) and remote residents (62% vs 8%, P < .001). Among Indigenous patients, a significantly greater proportion of domiciliary oxygen therapy was indicated for chronic obstructive pulmonary disease and bronchiectasis (16% vs 1%, P < .001). Among non-Indigenous patients, malignancies were a more common indication for domiciliary oxygen therapy. A similar proportion of Indigenous and non-Indigenous patients were prescribed domiciliary oxygen therapy for palliative intent (31% and 20%, P = .108); however, the underlying diagnosis differed significantly, with a greater proportion of chronic obstructive pulmonary disease among Indigenous patients (43% vs 13%, P = .030) and malignancy among the non-Indigenous patients (73% vs 43%, P = .050). Mortality and length of survival were not significantly different by Indigenous status. Linear regression showed longer survival with domiciliary oxygen therapy for chronic obstructive pulmonary disease. CONCLUSION: Indigenous Australian patients living in remote communities will likely derive the same benefits and outcomes of domiciliary oxygen therapy as non-Indigenous peers.

Maternal Anaemia in Pregnancy: A Significantly Greater Risk Factor for Anaemia in Australian Aboriginal Children than Low Birth Weight or Prematurity.

OBJECTIVES: To identify maternal and perinatal risk factors associated with childhood anaemia. METHODS: A retrospective cohort study was conducted in three remote Katherine East Aboriginal communities in Northern Territory, Australia. Children born 2004-2014 in Community A and 2010-2014 in Community B and C, and their respective mothers were recruited into the study. Maternal and child data were linked to provide a longitudinal view of each child for the first 1000 days from conception to 2-years of age. Descriptive analyses were used to calculate mean maternal age, and proportions were used to describe other antenatal and perinatal characteristics of the mother/child dyads. The main outcome was the prevalence of maternal anaemia in pregnancy and risk factors associated with childhood anaemia at age 6 months. RESULTS: Prevalence of maternal anaemia in pregnancy was higher in the third trimester (62%) compared to the first (46%) and second trimesters (48%). There was a strong positive linear association (R2 = 0.46, p < 0.001) between maternal haemoglobin (Hb) in third trimester pregnancy and child Hb at age 6 months. Maternal anaemia in pregnancy (OR 4.42 95% CI 2.08-9.36) and low birth weight (LBW, OR 2.62, 95% CI 1.21-5.70) were associated with an increased risk of childhood anaemia at 6 months of age. CONCLUSIONS FOR PRACTICE: This is the first study to identify the association of maternal anaemia with childhood anaemia in the Australian Aboriginal population. A review of current policies and practices for anaemia screening, prevention and treatment during pregnancy and early childhood would be beneficial to both mother and child. Our findings indicate that administering prophylactic iron supplementation only to children who are born LBW or premature would be of greater benefit if expanded to include children born to anaemic mothers.

Nutritional dual burden in Indigenous young adults: The geographical differential.

OBJECTIVE: Nutritional dual burden is defined as the coexistence of underweight and overweight in the same population. We report the rates of nutritional dual burden in Indigenous young men and women in the Northern Territory. Additionally, we examine the impact geographical area has on these rates. DESIGN: Cross-sectional data obtained from the longitudinal Aboriginal Birth Cohort Study. SETTING: Participants residing in over 40 urban and remote communities across the Top End of the Northern Territory. PARTICIPANTS: Young adults aged 23-28 years; urban (n = 99) and remote (n = 316). MAIN OUTCOME MEASURE(S): Anthropometric data was directly collected using standardised methods. Underweight was defined as BMI ≤ 18.5 kg/m2 and overweight/obese as body mass index ≥ 25 kg/m2 . Remote residency was categorised by established shires/regions (Vic/Daly, Arnhem and Tiwi). RESULTS: Significantly higher levels of underweight were seen in remote participants, compared to urban participants, irrespective of sex. Further differences were seen by regions, with the highest rates seen in Vic/Daly, compared to Arnhem and Tiwi. Higher rates of overweight/obesity were found in urban participants, compared to remote. The levels of overweight/obesity varied, depending on region of residence. CONCLUSION: Underweight and overweight patterns coexist in Indigenous young adults, with variation across geographical regions. Health programs need to take this dual nutritional burden into consideration to avoid worsening the severity of underweight, whilst reducing levels of overweight.

Chest computed tomography findings among adult Aboriginal Australians with bronchiectasis in the Top End Northern Territory of Australia.

INTRODUCTION: There is limited evidence in the literature illustrating chest computed tomography (CT) characteristics among adult Aboriginal Australians with bronchiectasis. This retrospective study evaluates the radiological characteristics of bronchiectasis in Aboriginal Australians residing in the Top End, Northern Territory of Australia. METHODS: Patients aged >18 years with chest CT-confirmed bronchiectasis between 2011 and 2020 were included. Demographics and relevant clinical parameters were collected. Alongside confirming bronchiectasis, chest CT reports were assessed for (i) lobar location (ii) unilateral or bilateral involvement and (iii) bronchiectasis type when available. RESULTS: A total of 459 patients were identified with chest CT-confirmed bronchiectasis, with a median age of 47 years, and 55% were females. Bronchiectasis was predominantly recorded in the left lower lobe (LLL) (73%), followed by the right lower lobe (RLL) (62%) and the left upper lobe (LUL) was least common (22%). Females recorded the right middle lobe (RML) affected significantly more often than males (50 vs. 34%, P = 0.012). Bilateral involvement was common (74%), with the strongest pairwise correlation associated between the right upper lobe (RUL) and LUL (P < 0.001). Cylindrical (50%) and cystic (28%) types were most common. The RML and LLL showed positive correlation with cylindrical and LUL with cystic bronchiectasis. Neither lobar location nor bronchiectasis type showed any significant association with lung function parameters other than RML, Lingula and LUL involvement being associated with better percent predicted values of diffusing capacity for carbon monoxide. There were no significant associations between sputum culture and type or lobar locations of bronchiectasis except for non-Aspergillus fungus culture prevalence was higher with cystic or cylindrical types. CONCLUSION: The results of this study may be an avenue to develop CT bronchiectasis severity scale in the future specific for Aboriginal Australians.

Cystic lung disease in adult Indigenous Australians in the Northern Territory of Australia.

INTRODUCTION: Indigenous Australians have a high prevalence of chronic lung diseases. However, no previous studies have reported on cystic lung disease in an Indigenous patient cohort. METHODS: This report describes 20 adult Indigenous patients noted to have incidental lung cysts on chest computed tomography (CT) while being referred to undergo lung function tests in the Northern Territory of Australia. RESULTS: Of the total 20 Indigenous patients demonstrating presence of pulmonary cysts on chest CT scan, 13/20 (65%) were males with a mean age of 49.9 years (range 24-74 years), with no significant difference in age between males and females. The majority reported a smoking history and spirometry demonstrated moderate reduction in lung function parameters. While there was no pattern in the size or location of cysts, most demonstrated multiple cysts (55% had ≥5 cysts) with bilateral involvement (65%), alongside a range of concurrent pulmonary radiological abnormalities. The aetiology for lung cysts was largely unknown. CONCLUSION: This is the first report to illustrate cystic lung disease within an Indigenous population. Further radiology studies are required to investigate the causes and prognostications of cystic lung disease in Indigenous patients.

Excessive daytime sleepiness is associated with relative delta frequency power among patients with mild OSA.

Background: Excessive daytime sleepiness (EDS) is a cause of low quality of life among obstructive sleep apnoea (OSA) patients. Current methods of assessing and predicting EDS are limited due to time constraints or differences in subjective experience and scoring. Electroencephalogram (EEG) power spectral densities (PSDs) have shown differences between OSA and non-OSA patients, and fatigued and non-fatigued patients. Therefore, polysomnographic EEG PSDs may be useful to assess the extent of EDS among patients with OSA. Methods: Patients presenting to Israel Loewenstein hospital reporting daytime sleepiness who recorded mild OSA on polysomnography and undertook a multiple sleep latency test. Alpha, beta, and delta relative powers were assessed between patients categorized as non-sleepy (mean sleep latency (MSL) ≥10 min) and sleepy (MSL <10 min). Results: 139 patients (74% male) were included for analysis. 73 (53%) were categorized as sleepy (median MSL 6.5 min). There were no significant differences in demographics or polysomnographic parameters between sleepy and non-sleepy groups. In multivariate analysis, increasing relative delta frequency power was associated with increased odds of sleepiness (OR 1.025 (95% CI 1.024-1.026)), while relative alpha and beta powers were associated with decreased odds. The effect size of delta PSD on sleepiness was significantly greater than that of either alpha or beta frequencies. Conclusion: Delta PSD during polysomnography is significantly associated with a greater degree of objective daytime sleepiness among patients with mild OSA. Further research is needed to corroborate our findings and identify the direction of potential causal correlation between delta PSD and EDS.

Factors influencing survival and mortality among adult Aboriginal Australians with bronchiectasis-A 10-year retrospective study.

Background: The prevalence of bronchiectasis among adult Aboriginal Australians is higher than that of non-Aboriginal Australians. However, despite evidence to suggest higher prevalence of bronchiectasis among Aboriginal people in Australia, there is sparce evidence in the literature assessing clinical parameters that may predict survival or mortality in this population. Methods: Aboriginal Australians residing in the Top End Health Service region of the Northern Territory of Australia aged >18 years with chest computed tomography (CT) confirmed bronchiectasis between 2011 and 2020 were included. Demographics, body mass index (BMI), medical co-morbidities, lung function data, sputum microbiology, chest CT scan results, hospital admissions restricted to respiratory conditions and all-cause mortality were assessed. Results: A total of 459 patients were included, of whom 146 were recorded deceased (median age at death 59 years). Among the deceased cohort, patients were older (median age 52 vs. 45 years, p = 0.023), had a higher prevalence of chronic obstructive pulmonary disease (91 vs. 79%, p = 0.126), lower lung function parameters (median percentage predicted forced expiratory volume in 1 s 29 vs. 40%, p = 0.149), a significantly greater proportion cultured non-Aspergillus fungi (65 vs. 46%, p = 0.007) and pseudomonas (46 vs. 28%, p = 0.007) on sputum microbiology and demonstrated bilateral involvement on radiology. In multivariate models advancing age, prior pseudomonas culture and Intensive care unit (ICU) visits were associated with increased odds of mortality. Higher BMI, better lung function on spirometry, prior positive sputum microbiology for Haemophilus and use of inhaled long-acting beta antagonist/muscarinic agents may have a favourable effect. Conclusion: The results of this study may be of use to stratify high risk adult Aboriginal patients with bronchiectasis and to develop strategies to prevent future mortality.

Sleep stage continuity is associated with objective daytime sleepiness in patients with suspected obstructive sleep apnea.

STUDY OBJECTIVES: Excessive daytime sleepiness (EDS) in patients with obstructive sleep apnea (OSA) is poorly explained by standard clinical sleep architecture metrics. We hypothesized that reduced sleep stage continuity mediates this connection independently from standard sleep architecture metrics. METHODS: 1,907 patients with suspected OSA with daytime sleepiness complaints underwent in-lab diagnostic polysomnography and next-day Multiple Sleep Latency Test (MSLT). Sleep architecture was evaluated with novel sleep-stage continuity quantifications (mean sleep stage duration and probability of remaining in each sleep stage), and conventional metrics (total N1, N2, N3 and REM times; and sleep onset latency). Multivariate analyses were utilized to identify variables associated with moderate EDS (5 ≤ mean daytime sleep latency (MSL) ≤ 10 minutes) and severe EDS (MSL < 5 minutes). RESULTS: Compared to those without EDS, participants with severe EDS had lower N3 sleep continuity (mean N3 period duration 10.4 vs 13.7 minutes, p<0.05), less N3 time (53.8 vs 76.5 minutes, p<0.05); greater total sleep time (374.0 vs 352.5 minutes, p<0.05) and greater N2 time (227.5 vs 186.8 minutes, p<0.05). After adjusting for standard sleep architecture metrics using multivariate logistic regression, decreased mean wake and N3 period duration, and the decreased probability of remaining in N2 and N3 sleep remained significantly associated with severe EDS, while the decreased probability of remaining in wake and N2 sleep were associated with moderate EDS. CONCLUSIONS: Patients with OSA with EDS experience lower sleep continuity, noticeable especially during N3 sleep and wake. Sleep-stage continuity quantifications assist in characterizing the sleep architecture and are associated with objective daytime sleepiness highlighting the need for more detailed evaluations of sleep quality.

Nocturnal oxygen resaturation parameters are associated with cardiorespiratory comorbidities.

BACKGROUND: There are strong associations between oxygen desaturations and cardiovascular outcomes. Additionally, oxygen resaturation rates are linked to excessive daytime sleepiness independent of oxygen desaturation severity. No studies have yet looked at the independent effects of comorbidities or medications on resaturation parameters. METHODS: The Sleep Heart Health Study data was utilised to derive oxygen saturation parameters from 5804 participants. Participants with a history of comorbidities or medication usage were compared against healthy participants with no comorbidity/medication history. RESULTS: 4293 participants (50.4% female, median age 64 years) were included in the analysis. Females recorded significantly faster resaturation rates (mean 0.61%/s) than males (mean 0.57%/s, p < 0.001), regardless of comorbidities. After adjusting for demographics, sleep parameters, and desaturation parameters, resaturation rate was reduced with hypertension (-0.09 (95% CI -0.16, -0.03)), myocardial infarction (-0.13 (95% CI -0.21, -0.04)) and heart failure (-0.19 (95% CI -0.33, -0.05)), or when using anti-hypertensives (-0.10 (95% CI -0.17, -0.03)), mental health medications (-0.18 (95% CI -0.27, -0.08)) or anticoagulants (-0.41 (95% CI -0.56, -0.26)). Desaturation to Resaturation ratio for duration was decreased with mental health (-0.21 (95% CI -0.34, -0.08)) or diabetic medications (-0.24 (95% CI -0.41, -0.07)), and desaturation to resaturation ratio for area decreased with heart failure (-0.25 (95% CI -0.42, -0.08)). CONCLUSIONS: Comorbidities and medications significantly affect nocturnal resaturation parameters, independent of desaturation parameters. However, the causal relationship remains unclear. Further research can enhance our knowledge and develop more precise and safer interventions for individuals affected by certain comorbidities.