Background Prevalence of bronchiectasis among the adult Aboriginal Australians is high, estimated to be up to 19.4/1000 people, with associated higher morbidity and mortality. However, despite evidence to suggest that adult Aboriginal Australians have higher bronchiectasis disease burden, the knowledge surrounding sputum antimicrobial susceptibility data is sparce. Objectives To assess the sputum antimicrobial susceptibility patterns among adult Aboriginal patients with bronchiectasis in the Northern Territory of Australia. Design Retrospective study. Method Patients aged 18 years and over with sputum antimicrobial susceptibility results available between 2011-2020 during a respiratory related hospital admission (restricted to ICD J presentations) were included. The sputum samples were processed and antibacterial susceptibility reported as per recommended selective susceptibility testing guidelines. Results A total of 183 patients had positive sputum cultures. Of these, 167 had antimicrobial susceptibility tested. Antimicrobial resistance to at least one antibiotic was noted for Haemophilus spp. 12 (7%), Pseudomonas spp. 26 (15.4%), Streptococcus pneumoniae 18 (23.1%), Staphylococcus spp. 17 (47.2%) and Klebsiella spp. 8 (88.9%). The greatest frequency of antimicrobial resistance was recorded against Ampicillin for Haemophilus spp . (5.8%), Ceftazidime for Pseudomonas spp. (7.7%), Erythromycin for Streptococcus pneumoniae (20.5%), Flucloxacillin and Amoxycillin/Clavulanate for Staphylococcus spp. (27.8%) and Ampicillin for Klebsiella spp. (88.9%). Multi-antimicrobial resistance was recorded in 31 unique patients. In univariate logistic regression models advancing age was associated with increased odds for antimicrobial resistance for Haemophilus spp. and patients with multi-antimicrobial resistance recorded a higher hospitalisation rate (median 14 vs. 8), more hours in intensive care (median 225.5 vs. 131) and left upper lobe bronchiectasis (41.9 vs 20.4%). Although, statistically not significant, the overall mortality was higher among patients demonstrating multi-antimicrobial resistance, including younger age at death. Conclusion The results of this study may be of utility in advocating antimicrobial stewardship among adult Aboriginal/Indigenous patients with bronchiectasis.

Objective.Obstructive sleep apnea (OSA) increases circulatory system load and risk of cardiovascular diseases (CVDs). Despite being biomarkers of vascular health, photoplethysmography (PPG) signal waveforms have not been systematically investigated in patients with OSA. Thus, we aimed to study the immediate effects of respiratory event characteristics on PPG waveforms and to examine potential patterns that could be associated with cardiovascular health.Approach.We retrospectively analyzed 520 clinical polysomnographies from suspected OSA patients, focusing on three PPG signal segments: 10 s before, during, and 10 s after respiratory events (n= 14442 in each segment). We determined PPG waveform parameters (full width at half maximum (FWHM) as well as differences in absolute and relative time (Δt, Δtrel) and amplitude (ΔA, and ΔArel) between systolic peak and dicrotic notch) within each segment and tested the effect of respiratory event type (apnea vs hypopnea) and duration (10-20 s, 20-30 s, ⩾30 s).Main results.Before and during respiratory events, longer respiratory events significantly (p< 0.001) increased ΔAreland FWHM, and decreased ΔAand Δtrel. These findings were significantly (p< 0.001) more pronounced during apneas than hypopneas. After the events, all PPG waveform parameters fluctuated strongly. Moreover, the type and duration of the respiratory event, pre-event values of PPG parameters, and heart rate were significantly (p< 0.001) associated with changes in the parameter values during the event.Significance.By analyzing PPG characteristics, we could enhance the evaluation of physiological stress caused by respiratory events in patients with OSA and therefore provide tools for the risk assessment of CVDs.

Obstructive sleep apnea (OSA) is a common nocturnal breathing disorder characterized by recurrent upper airway obstruction during sleep, leading to sleep fragmentation and intermittent hypoxemia. The apnea-hypopnea index (AHI) is the most widely used clinical metric to assess OSA severity; however, the AHI fails to capture the full physiological burden caused by recurrent oxygen desaturations. Consequently, quantifying hypoxemia, the cumulative burden of oxygen desaturations, has become crucial for assessing the physiological impact of OSA more comprehensively. Furthermore, studies have illustrated that hypoxemia is associated with cardiovascular morbidity, metabolic dysfunction, and neurocognitive impairment in OSA patients. This narrative review aims to explore various methods used to quantify nocturnal hypoxemia from sleep recordings and discuss the different approaches, and their association with OSA-related comorbidities. The discussed metrics include traditional measures and newer parameters that provide a more detailed quantification of oxygen desaturation, including separate characterization of desaturation and re-saturation dynamics as well as integrated measures of the overall hypoxic load. Additionally, this review discusses how these more detailed metrics have provided further insight into the associations between OSA-related hypoxemia and clinically relevant outcomes, including cardiometabolic comorbidities and impaired daytime functioning. This narrative review emphasizes the need for diagnostic modifications and advocates for the integration of metrics quantifying hypoxemia into routine clinical practice to enable early recognition of the health risks associated with OSA.

Abstract This study examined inter‐community‐based variations in spirometry parameters in 243 Aboriginal patients aged >18 years from 14 individual remote communities (61% female, with a median age of 54.6 years). Mixed ventilatory impairment was the most common pattern (51.6%), followed by restrictive (32.4%) and obstructive (9.8%). Significant inter‐community variability was observed, ranging for mixed (85.7% to 37.5%), restrictive (62.5% to none) and obstructive (20% to none). These findings indicate a more tailored approach is needed to address lung health in rural and remote residing adult Aboriginal Australians.

This paper comprehensively examines the evolution of OSA screening tools from 1991 to 2025 and evaluates their clinical applicability. Thirty-one screening tools have been developed over the last three decades (from the Epworth Sleepiness Scale (ESS) in the 1990’s to the General Practice Sleep Scale (GPSS) in 2025), varying in their structure, population base, and diagnostic thresholds. Earlier tools primarily targeted high-risk, clinic-based cohorts, while newer tools attempt to address limitations in sensitivity, inclusivity, and usability in general practice and community settings. Variability in definitions (e.g. Apnoea/hypopnoea index (AHI) thresholds, symptom scoring) and population characteristics (e.g. age, sex, ethnicity, comorbidities) impacts the performance and generalisability of existing tools. No single OSA screening tool is universally applicable across diverse populations. While newer tools like the GPSS show promise by addressing demographic and clinical diversity, further validation in international and ethnically varied cohorts is needed.

Bronchiectasis is a significant health burden among Australian Indigenous adults and global Indigenous populations, particularly those in rural and remote communities. This review synthesizes the current literature and integrates insights from local and national experts to inform a culturally appropriate and clinically effective approach to bronchiectasis management in this population. Recent findings highlight a high prevalence of bronchiectasis among Australian Indigenous adults (14.9 per 1,000), with common symptoms including chronic cough, sputum production, and dyspnoea. Clinical signs may include coarse crackles, digital clubbing, and reduced BMI, often accompanied by coexisting COPD and other comorbidities. While chest CT remains the diagnostic gold standard, clinical features and chest X-rays can support a presumptive diagnosis where access is limited. Spirometry typically reveals restrictive patterns, and sputum cultures frequently identify Haemophilus influenzae, Pseudomonas aeruginosa, and non-Aspergillus fungi. The Indigenous Bronchiectasis Assessment Scale (IBAS) may assist in evaluating disease burden. Key management strategies include patient education, airway clearance, smoking cessation, nutritional support, physical activity, and vaccination. Pharmacologic therapies such as long-acting bronchodilators, azithromycin, and N-acetylcysteine may be beneficial, whereas inhaled corticosteroids should be used cautiously. This report proposes a tailored clinical framework aimed at reducing morbidity and mortality in Indigenous adults with bronchiectasis.

Sleep stages exhibit differing patterns of cardiac, respiratory and nervous system activation. Rapid eye movement (REM) sleep is associated with deeper oxygen desaturation events in obstructive sleep apnea. However, no studies have looked to the effect of sleep staging on re-saturation characteristics. Polysomnographic data from the Sleep Heart Health Study were utilised to derive oxygen saturation parameters from events having both desaturation and re-saturation parts. Sleep stages were described as non-REM (NREM) 1 or 2 (combined), 3 and REM. Sleep stage effects on desaturation and re-saturation characteristics were investigated in a healthy subgroup (n = 759) and participants with hypertension (n = 2534), lung disease (n = 715), heart failure (n = 199) and myocardial infarction (n = 713). A total of 3793 participants (48.3% female) were included for analysis (171,976 saturation events; median 20 per participant). Events during REM had the longest duration, deepest nadirs and greatest area for desaturations and re-saturations. Sleep stage effected re-saturation parameters more than desaturation parameters, with a relative difference from NREM 1/2 to REM in duration of 16.7% and 29.8%, in rate of 0.2% and 4.5% and in area of 36.1% and 48.0% for desaturation and re-saturation, respectively, among healthy participants. Similarly, the effect of comorbidities was greater upon re-saturations than desaturations, as participants with heart failure recorded a relative difference to healthy participants of 10.3% and 24.4% for desaturation and re-saturation duration, respectively, 12.8% and 15.0% for rate and 6.4% and 16.4% for area. Sleep stages and comorbidities have significant effects upon nocturnal oxygen re-saturation parameters. Cardiorespiratory comorbidities elicit greater degradations in oxygen re-saturations than they do desaturations.

Background Globally, adult Indigenous people, including Aboriginal Australians, have a high burden of chronic respiratory disorders, and bronchiectasis is no exception. However, literature detailing bronchiectasis disease characteristics among adult Indigenous people is sparse. This study assessed the clinical profile of bronchiectasis among adult Aboriginal Australians and compared against previously published international bronchiectasis registry reports.Methods Aboriginal Australians aged >18 years with chest CT confirmed bronchiectasis between 2011 and 2020 in the Top End Northern Territory of Australia were included. Demographics, chest CT findings, pulmonary function results, sputum microbiology, coexistent medical comorbidities, and pharmacotherapy use were assessed and compared against five published international bronchiectasis registry reports (Australian (ABR), European (European Multicentre Bronchiectasis Audit and Research Collaboration (EMBARC)-Europe), Indian (EMBARC-India), Korean (KMBARC) and the USA (USBRR)).Results A total of 459 patients were assessed. In comparison with international and non-Aboriginal Australian national cohorts, Aboriginal Australians were younger (median 56 years (IQR (48, 65)); however, sex distribution (55% female) and body mass index (23 kg/m2 (IQR 19.4–27)) were comparable . Smoking rates were higher at 85% compared with other registry cohorts (22–46%) as was the prevalence of comorbidities (97%): cardiovascular diseases (73%), diabetes mellitus (50%) and chronic obstructive pulmonary disease (83%) compared with other registry cohorts (4–32%; 6–14%; and 14–37%, respectively). Spirometry demonstrated forced expiratory volume in 1 s of 38% predicted in comparison with 61–77% in other cohorts. Sputum microbiology showed Haemophilus influenzae (57%) isolated at 3.4 to 6 times the rate of other registry cohorts and Pseudomonas aeruginosa in 31%. Chest CT demonstrated multilobar and lower lobes involvement in 73% and inhaled pharmacotherapy use was recorded in up to 62% and long-term antibiotics in 5%.Conclusion The overall bronchiectasis disease burden is higher in Aboriginal Australian adults in comparison with global ethnically diverse non-Indigenous populations. Further efforts are required to address this disparity secondary to bronchiectasis among Indigenous people.

This cross-sectional study assessed the clinical and economic costs (Inpatient Activity Database) associated with hospitalisations due to bronchiectasis exacerbations among adult indigenous patients in the Top End, Northern Territory. Twenty case episodes from 15 indigenous patients with a mean age of 51.8 ± 12.7 years were recorded in a 3-month study window. The estimated cost was AUD 400 579.9, with cost per patient AUD 26 705 over 3 months and average cost per admission AUD 20 029. Extrapolating cost data across a 10-year period gave a conservative estimate of AUD 28 million.

Chronic respiratory disorders are highly prevalent among adult Aboriginal and Torres Strait Islander peoples, with emerging evidence suggesting that there is a significant burden of bronchiectasis contributing to overall higher morbidity and mortality. Despite this, bronchiectasis in adult Aboriginal Australians has attracted little attention in the past few decades, and only recently is published evidence on this topic beginning to emerge. This paper highlights recent insights into the disease profiles of bronchiectasis among adult Aboriginal populations, revealing a particularly high prevalence among rural and remote residing Aboriginal people that is disproportionately higher in comparison to global diverse ethnic cohorts. Studies reveal differences in disease characteristics as well as prevalence, with higher presence of multi-morbidity, impaired lung function (spirometry), multi-lobar involvement on chest radiology and higher bacterial load measured in sputum. In addition, hospital admission rates and all-cause mortality are high, significantly influencing the economic impact. These findings highlight the need for further research into the unique characteristics of bronchiectasis in adult Aboriginal Australian patients and highlight the need for targeted action.

BACKGROUND:There is a lack of a comprehensive bronchiectasis severity assessment tool specific for Indigenous people that corrects for normative references established for the non-Indigenous population. AIMS:An innovative bronchiectasis assessment tool is developed for use in adult Indigenous patients - the Indigenous bronchiectasis assessment scale '(IBAS)'. METHODS:A total of 454 adult Indigenous Australian patients, with chest CT confirmed bronchiectasis diagnosed between 2011 and 2020, were included. Age, sex, residence location, body mass index, radiological findings, sputum microbiology, lung function parameters and medical comorbidities were utilised to predict 5-year all-cause mortality and 5-year hospitalisations. Scores of parameters with P < 0.20 from univariate Cox regressions were derived. RESULTS:The resultant IBAS included age (<30, 30-50, 50-70 and 70+ years), urban residence, forced vital capacity (% predicted) (>50%, 30%-50% and <30%), right lower lobe involvement, history of Haemophilus spp., Pseudomonas spp., yeast spp. or Moraxella spp., 2-year respiratory condition hospitalisation history (<2, 2 and 3+ admissions), and comorbid chronic obstructive pulmonary disease, asthma and arterial hypertension. The maximum score was 18, with thresholds at 0-4 (mild, n = 78, 34.4%), 5-7 (moderate, n = 111, 48.9%) and ≥ 8 (severe, n = 38, 16.7%). The area under the curve for 5-year mortality was 0.743 (95% confidence interval (CI) 0.683, 0.803). The IBAS score demonstrated significant delineation in mortality between mild and moderate (moderate hazard ratio (HR) 3.45 (95% CI 1.57, 7.58)) and between moderate and severe (severe HR 2.43 (95% CI 1.45, 4.07)). CONCLUSION:The proposed IBAS tool could be of aid in assessing bronchiectasis severity in Indigenous patients.

The GPSS is a new tool for screening at risk patients for obstructive sleep apnoea (OSA) at primary healthcare. However, the GPSS was designed and developed amongst a relatively small and young population with a high pre-test probability of OSA. To better define the accuracy and validity of this tool, broader, community sampled populations are needed. We utilised first visit data from the Sleep Heart Health Study (SHHS), defining OSA as an AHI≥15. Questions 5-8 of the GPSS (snoring, witnessed apnoeas, sleepiness and presence of hypertension/diabetes/heart disease/depression) were not directly assessed in the SHHS, thus derived from composites. We compared the GPSS against the STOP-Bang (derived in a similar manner to the GPSS) and the Epworth sleepiness scale (ESS). 3959 (47.6% female median age 63-years, BMI 27.8) participants had data available to be included. 943 (23.8%) recorded OSA. The median GPSS was 8 (IQR 5, 11), STOP-Bang 3 (IQR 2, 4) and ESS 8 (5, 11). The total continuous GPSS score was significantly associated with OSA (OR 1.24 (95% CI 1.21, 1.26)). GPSS moderate (>7) significantly increased odds for OSA compared to mild (≤7) (OR 3.18 (95% CI 2.59, 3.90)), and GPSS severe (>13) did so compared to moderate (OR 2.59 (95% CI 2.16, 3.11)). Sensitivity and specificity of GPSS moderate was 85.8 & 41.9% respectively, correctly classifying 52.3%, and of GPSS severe was 35.1 & 87.7% respectively, correctly classifying 75.2%. Sensitivity and specificity of STOP-Bang ≥3 was 77.8 & 54.8% respectively, correctly classifying 60.3%, and ESS ≥11 was 34.6 & 74.3% respectively, correctly classifying 64.9%. The ROC, AUC for the 3-level GPSS was 0.69 (95% CI 0.67, 0.71). For the 2-level STOP-Bang this was 0.66 (95% CI 0.65, 0.68) and for the 2-level ESS 0.55 (95% CI 0.53, 0.56). Due to the higher age in the SHHS compared to the GPSS development cohort, we tested adding additional scores for age thresholds 60-75 & >75. This slightly improved the 3-level GPSS AUC to 0.70 (9%% CI 0.68, 0.72). The GPSS is a valid and reliable tool in a community setting and appears to outperform both the STOP-Bang and the ESS.

BACKGROUND:Sputum microbiology is an integral aspect of managing patients with bronchiectasis. Adult Aboriginal Australians have a high bronchiectasis disease burden; however, as yet there is sparce literature detailing the sputum microbiology profile in this population. AIMS:To assess the sputum microbiology profile among Aboriginal patients aged ≥18 years with chest computed tomography-confirmed bronchiectasis in the Top End Northern Territory of Australia. METHOD:All available sputum samples processed in a single laboratory service with established protocols for examining and reporting sputum microbiology results between 2011 through 2020 were assessed in relation to demographics, lung function parameters, chest radiology, inhaled pharmacotherapy, hospital admissions restricted to respiratory conditions and all-cause mortality. RESULTS:Four hundred twenty-eight patients (median age 47 years, 56% female) had sputum cultures available to assess. Haemophilus spp. was the most common (64%), followed by yeast/Candida spp. (53%) and Pseudomonas spp. (36%). Polymicrobial cultures were noted in 92% of patients. There were significant geographic differences on a region-wise and community-wise basis. Patients with yeast/Candida spp. and Pseudomonas spp. recorded more hospitalisations (median 7 (interquartile range (IQR) 3-14) and 8 (IQR 4-16)). In multivariate models, both yeast/Candida spp. (odds ratio (OR) 2.63 (95% confidence interval (CI) 1.68-4.14)) and Pseudomonas spp. (OR 1.95 (95% CI 1.25-3.04)) were associated with increased odds for mortality. Other than higher Pseudomonas spp. isolated with the use of inhaled corticosteroids, no significant association was observed either with lung function or chest radiology. CONCLUSION:Adult Aboriginal Australians with bronchiectasis harbour a significant microorganism load that may play a role in overall morbidity and mortality.

Background Studies assessing normative values and sex differences in pulmonary function test parameters (PFTPs) among Indigenous populations are sparse. Methods PFTPs were compared between male and female Indigenous Australian adults with and without chest radiologically proven chronic airway diseases (CADs). Results 485 adults (56% were female) with no significant difference in age, body mass index or smoking status between sexes were included. Females displayed a higher prevalence of radiology without CADs compared to males (66 vs. 52%, respectively). Among patients without CADs, after adjustment for age, stature and smoking, males displayed significantly higher absolute values of Forced Vital Capacity (FVC) (mean difference, 0.41L (0.21,0.62), p<0.001) and Forced Expiratory Volume in one second (FEV1) (mean difference 0.27L (0.07,0.47), p<0.001), with no significant difference in FEV1/FVC ratio (mean difference -0.02 (-0.06, 0.02), p = 0.174). Male and female patients with radiologically proven CADs demonstrated lower FEV1/FVC values. However, compared to females, males showed significantly greater reductions in pre- [-0.53 (-0.74, -0.32) vs. -0.29 (-0.42, -0.16), p = 0.045] and post- [-0.51 (-0.72, -0.3) vs. -0.27 (-0.39, -0.14), p = 0.049] bronchodilator FEV1. Conclusions There are significant sex differences in the PFTPs among Indigenous Australians. Recognising these differences may be of value in the accurate diagnosis, management, monitoring and prognostication of CADs in this population.

AbstractIntroductionThere are limited data on chest computed tomography (CT) findings in the assessment of lung nodules among adult Aboriginal Australians. In this retrospective study, we assessed lung nodules among a group of adult Aboriginal Australians in the Northern Territory of Australia.MethodsPatients who underwent at least two chest CT scans between 2012 and 2020 among those referred to undergo lung function testing (spirometry) were included. Chest CT scans were assessed for the number, location, size and morphological characteristics of lung nodules.ResultsOf the 402 chest CTs assessed, 75 patients (18.7%) had lung nodules, and 57 patients were included in the final analysis with at least two CT scans available for assessment over a median follow‐up of 87 weeks. Most patients (68%) were women, with a median age of 58 years and smoking history in 83%. The majority recorded only a single nodule 43 (74%). Six patients (10%) were diagnosed with malignancy, five with primary lung cancer and one with metastatic thyroid cancer. Of the 51 (90%) patients assessed to be benign, 64 nodules were identified, of which 25 (39%) resolved, 38 (59%) remained stable and one (1.8%) enlarged on follow‐up. Nodules among patients with malignancy were typically initially larger and enlarged over time, had spiculated margins and were solid, showing no specific lobar predilection.ConclusionsMost lung nodules in Aboriginal Australians are likely to be benign. However, a proportion could be malignant. Further prospective studies are required for prognostication and monitoring of lung nodules in this population.