Search

Timothy Howarth,1,2 Claire Gibbs,3 Asanga Abeyaratne,4 Subash S Heraganahally1,3,5,6 1Darwin Respiratory and Sleep Health, Darwin Private Hospital, Darwin, NT, Australia; 2Department of Technical Physics, University of Eastern Finland, Kuopio, North Savo, Finland; 3Department of Respiratory and Sleep Medicine, Royal Darwin Hospital, Darwin, NT, Australia; 4Menzies School of Health Research, Darwin, Northern Territory, Australia; 5Flinders University, College of Medicine and Public Health, Darwin, NT, Australia; 6School of Medicine, Charles Darwin University, Darwin, NT, AustraliaCorrespondence: Subash S Heraganahally, Respiratory and Sleep Medicine, Department of Respiratory and Sleep Medicine, Royal Darwin Hospital, 105, Rocklands Drive, Tiwi, Darwin, NT, Australia, Tel +61-8-89228888, Fax +61-8-89206309, Email hssubhashcmc@hotmail.comBackground: The prevalence of bronchiectasis is significantly higher among adult Aboriginal Australians (the Indigenous peoples of Australia) compared to non-Aboriginal Australians. Currently, there is no well-established tool to assess bronchiectasis severity specific to Indigenous peoples. Nor has the applicability and validity of the two well-established bronchiectasis severity assessment tools - The “Bronchiectasis Severity Index” (BSI) and “FACED” scale been vigorously tested in an Indigenous population. This retrospective study evaluated the validity of the BSI and FACED amongst an adult Aboriginal Australian cohort with bronchiectasis in the Top End Northern Territory (NT) of Australia.Methods: Patients with CT confirmed bronchiectasis identified between 2011 and 2020, residing in the Top End of the NT were eligible to be enrolled. The primary endpoint of 4-year mortality was assessed via hospital records, and sensitivity and specificity of the BSI and FACED assessed against this using area under the curve (AUC) receiver operating characteristics analysis. For patients with missing data, a relative BSI / FACED score was used which divided the score recorded for that patient by the total potential score based on their available clinical data.Results: A total of 456 adult Aboriginal Australian patients > 18 years of age were included (55.5% female, median age 49 years). According to the BSI score 43.4% of patients were assessed to have mild, 30.5% moderate and 26.1% severe bronchiectasis (median score 4 (IQR 2, 8)). According to the FACED 80.9% were assessed to have mild, 17.8% moderate and 1.3% severe (median score of 1 (IQR 0, 2)). Four-year mortality was 11.2% (median age of death 55.6 years). Sensitivity and specificity of the BSI combining moderate and severe were 86.3 and 47.2% respectively, and for severe alone 51% and 77%. Sensitivity and specificity of the FACED combining moderate and severe were 21.6% and 81.2%, respectively, and for severe alone 2% and 98.8%. The AUC for the continuous total BSI was 0.703, and the FACED 0.515. Utilising a relative score, based only on data available for patients with missing data (ie lung function or BMI) resulted in slightly improved AUCs for both the BSI (0.717) and FACED (0.571).Conclusion: Both BSI and FACED bronchiectasis assessment tools may not be ideal in an Indigenous/Aboriginal people’s context. However, it may be reasonable to utilise the relative BSI score in this population until Indigenous people’s specific bronchiectasis severity assessment tools are developed.Plain Language Summary: Adult Indigenous people globally have a higher prevalence of chronic respiratory disorders, and bronchiectasis is no exception. To assess the bronchiectasis severity and to predict future mortality, there are well-established assessment tools. However, the existing bronchiectasis assessment tools are developed predominately from data gathered from non-Indigenous population cohorts. To date, it is unclear if these existing bronchiectasis assessment tools are appropriate or applicable for Indigenous people. Therefore, this study assessed how existing bronchiectasis tools, namely the “Bronchiectasis Severity Index” (BSI) and “FACED” [Forced expiratory volume in 1 s, Age, Chronic colonization, Extension, and Dyspnea] fit for an adult Indigenous/ Aboriginal Australian cohort diagnosed to have bronchiectasis. The results of the study showed that both BSI and FACED assessment tools may not be ideal in the Australian Indigenous/Aboriginal population, due to population demographics and other social determinants, including geographical isolation. Hence, further research is warranted in developing Indigenous/Aboriginal specific bronchiectasis assessment tools.Keywords: assessment, hospital admissions, scale, severity, spirometry, tool

Timothy Howarth,1– 3 Helmi Ben Saad,4 Subash S Heraganahally1,5,6 1Darwin Respiratory and Sleep Health, Darwin Private Hospital, Darwin, Northern Territory, Australia; 2Department of Technical Physics, University of Eastern Finland, Kuopio, Finland; 3College of Health and Human Sciences, Charles Darwin University, Darwin, Northern Territory, Australia; 4Faculté de Médecine de Sousse, Hôpital Farhat HACHED de Sousse, Laboratoire de recherche “Insuffisance Cardiaque” (LR12SP09), Université de Sousse, Sousse, Tunisia; 5Department of Respiratory and Sleep Medicine, Royal Darwin Hospital, Darwin, Northern Territory, Australia; 6College of Medicine and Public Health, Flinders University, Adelaide, South Australia, AustraliaCorrespondence: Subash S Heraganahally, Email hssubhashcmc@hotmail.com; Subash.heraganahally@nt.gov.auBackground: Sleep disorders such as obstructive sleep apnoea (OSA) are known to overlap significantly with airway diseases in various populations. This study assessed the relationship between lung function parameters against polysomnography (PSG) and continuous positive airway pressure (CPAP) adherence data amongst an Aboriginal Australian population.Methods: Patients who undertook both a diagnostic PSG and spirometry were included. Restrictive, obstructive, and mixed impairments were assessed via global lung function initiative (GLI-2012, ATS/ERS) criteria/guidelines. PSG and CPAP data were evaluated between patients with or without spirometry impairments.Results: Of the total 771 patients, 248 had PSG and spirometry data available (52% female, 44% remote residents, 78% obese). The majority (89%) had OSA (51% severe), 95 (38%) were observed to have a restrictive impairment, and 31 (13%) had an obstructive or mixed impairment on spirometry. Compared to patients with no spirometric impairment, those with restrictive or obstructive/mixed impairments demonstrated significantly lower sleep efficiency (median 84% vs 79% and 78%), higher apnoea-hypopnea index (AHI) during rapid eye movement (REM) sleep (median 32 vs 52 and 55 events/hour), reduced REM oxygen saturation (SpO2) (median 94.0% vs 92.0% and 92.5%) and reduced adherence to CPAP therapy (median 39% vs 22% and 17%). Differences in sleep efficiency, REM AHI, and NREM SpO2 held for patients with obstructive/mixed impairments in multivariate modelling.Conclusion: Aboriginal Australian patients with OSA have a higher concurrent lung function’ impairment. Spirometric impairment appears to negatively influence sleep efficiency, nocturnal SpO2 and CPAP adherence. This may have substantial implications for OSA management among Aboriginal Australians.Keywords: COPD, CPAP, first nations, OSA, sleep apnoea, spirometry

Edmund Benn,1 Hugh Wirth,1 Teagan Short,1 Timothy Howarth,2,3 Subash S Heraganahally1,3,4 1College of Medicine and Public Health, Flinders University, Adelaide, South Australia, Australia; 2College of Health and Human Sciences, Charles Darwin University, Darwin, Northern Territory, Australia; 3Darwin Respiratory and Sleep Health, Darwin Private Hospital, Darwin, Northern Territory, Australia; 4Department of Respiratory and Sleep Medicine, Royal Darwin Hospital, Darwin, Northern Territory, AustraliaCorrespondence: Subash S HeraganahallyDepartment of Respiratory and Sleep Medicine, Royal Darwin Hospital, Tiwi, Darwin, NT, AustraliaTel +61-8-89228888Fax +61-8-89206309Email hssubhashcmc@hotmail.comPurpose: To illustrate the utility of a newly developed culturally safe and clinically relevant subjective daytime sleepiness assessment tool “Top End Sleepiness Scale” (TESS) for use among Indigenous Australians.Patients and Methods: The TESS questionnaire consists of pictorial representations of 6 items representing daily activities that would induce daytime sleepiness specific for Indigenous Australians living in the regional and remote Australia. Consecutive adult Indigenous patients who consented to pilot the TESS questionnaire prior to undergoing a diagnostic polysomnography (PSG) at the Top End Health Service region, Northern Territory of Australia were assessed. The TESS questionnaire was evaluated for its correlation in predicting obstructive sleep apnea (OSA) according to apnea-hypopnea index.Results: Eighty-two patients were included. The majority (70%) had moderate to severe OSA (AHI ≥ 15). Patients were aged in their mid-40’s (45.47 95% CI (42.9, 48.05)) with a tendency to obesity (median BMI 33.67 IQR 30.86, 38.95) and a high prevalence of chronic conditions (72%) (hypertension, diabetes or heart disease). The TESS showed high internal consistency (Split half Spearman correlation=0.71, Cronbach’s α =0.81), and a cut-off value ≥ 3 resulted in sensitivity 84%, specificity 38%. Comparison of area under the curve for TESS to Epworth Sleepiness Scale (ESS) in this sample showed the TESS to have greater sensitivity and specificity overall, which approached significance (p=0.072) when cut-off values of ≥ 3 and ≥ 8 (TESS & ESS respectively) were used. The sensitivity and specificity for TESS was also comparable to the other currently used questionnaires, such as the Berlin Questionnaire, STOP-BANG and OSA 50.Conclusion: Currently, there are no subjective daytime sleepiness assessment toll available specifically for Indigenous population. The proposed TESS sleepiness screening tool represented in this study can potentially complement or adopted alongside other existing questionnaire, which may offer greater utility in the assessment of sleep disorders among Indigenous people.Keywords: First Nations, Aboriginal, Epworth Sleepiness Scale, indigenous, Sleepiness Scale, subjective daytime sleepiness

Himanshu Garg,1 Xin Yi Er,1 Timothy Howarth,2,3 Subash S Heraganahally1,3,4 1Department of Respiratory and Sleep Medicine, Royal Darwin Hospital, Darwin, Northern Territory, Australia; 2College of Health and Human Sciences, Charles Darwin University, Darwin, Northern Territory, Australia; 3Darwin Respiratory and Sleep Health, Darwin Private Hospital, Tiwi, Darwin, Northern Territory, Australia; 4Flinders University – College of Medicine and Public Health, Adelaide, South AustraliaCorrespondence: Subash S HeraganahallyDepartment of Respiratory and Sleep Medicine, Royal Darwin Hospital, 105, Rocklands Drive, Tiwi, Darwin, NT, AustraliaTel +61-8-89228888Fax +61-8-89206309Email hssubhashcmc@hotmail.comPurpose: To assess the prevalence of positional sleep apnea (POSA) and its predictors in patients diagnosed to have obstructive sleep apnea (OSA) in the regional and remote population of the Northern Territory of Australia over a two-year study period (2018 and 2019).Patients and Methods: Of the total 1463 adult patients who underwent a diagnostic polysomnography (PSG), 946 patients were eligible to be included in the study, of them, 810 consecutive patients with OSA (Apnea-Hypopnea Index (AHI) ≥ 5) who slept > 4 h and had ≥ 30 min sleep in both supine and lateral positions were assessed. Patients were considered to have POSA if supine AHI to lateral AHI ratio ≥ 2. The likely comparative impact of use of continuous positive airway therapy (CPAP) or positional therapy (PT) on disease severity was evaluated using model simulation.Results: A total of 495/810 (61%) patients had POSA, the majority were males (68% vs 60%, p=0.013) and non-Indigenous Australians (93% vs 87%, p=0.004). POSA patients were younger (mean difference 2.23 years (95% CI 0.27, 4.19)), less obese (BMI mean difference 3.06 (95% CI 2.11, 4.01)), demonstrated less severe OSA (p < 0.001) and a greater proportion reported alcohol consumption (72% vs 62%, p=0.001) as compared to those with non-POSA. Using the simulation model, if patients with POSA use PT two-thirds (323/495, 65%) would obtain significant improvement of their OSA severity, with one in five (92/495, 19%) displaying complete resolution. Comparing this to simulated CPAP therapy, where the majority (444/495, 90%) will show significant improvement, and one-third (162/495, 33%) will display complete resolution.Conclusion: POSA needs to be routinely recognised and positional therapy integrated in practice especially in the remote regions and in the developing world when effective methods are in place to monitor positional therapy.Keywords: adherence: apnea hypopnea index, body mass index, continuous positive airway pressure, obstructive sleep apnea, positional therapy

Subash S Heraganahally,1– 3 Timothy P Howarth,3,4 Angus Lloyd,1 Elisha White,3 Antony Veale,5 Helmi Ben Saad6 1Department of Respiratory and Sleep Medicine, Royal Darwin Hospital, Darwin, Northern Territory, Australia; 2College of Medicine and Public Health, Flinders University, Adelaide, South Australia, Australia; 3Darwin Respiratory and Sleep Health, Darwin Private Hospital, Darwin, Northern Territory, Australia; 4College of Health and Human Sciences, Charles Darwin University, Darwin, Northern Territory, Australia; 5Department of Respiratory and Sleep Medicine, Queen Elizabeth Hospital, Adelaide, South Australia, Australia; 6Faculty of Medicine of Sousse, Hospital Farhat HACHED of Sousse, Research Laboratory “Heart Failure, LR12SP09”, University of Sousse, Sousse, TunisiaCorrespondence: Subash S Heraganahally, Department of Respiratory and Sleep Medicine, Royal Darwin Hospital, Darwin Respiratory and Sleep Health, Darwin private Hospital, Darwin, Northern Territory, Australia, Tel +61-8-89228888 ; +61-8-89206306, Fax +61-8-89206309, Email hssubhashcmc@hotmail.com; Subash.heraganahally@nt.gov.auBackground: Among Indigenous Australians, studies examining the clinical significance of airway bronchodilator responsiveness (BDR) are limited. In this retrospective study, we examined the nature of underlying lung disease in adult Indigenous patients with BDR referred for lung function testing (LFT) in the Top End Health Service region of the Northern Territory of Australia.Methods: Presence or absence of BDR as per usual (FVC or FEV1 change pre to post ≥ 12% and ≥ 0.2L) and updated (2021 “> 10% predicted) ATS/ERS criteria among Indigenous and non-Indigenous Australians was determined. The radiological findings in the Indigenous study participants with and without BDR were next assessed for the presence of underlying chronic airway/lung disease.Results: We found that 123/742 (17%) Indigenous and 578/4579 (13%) non-Indigenous patients had a significant BDR. Indigenous patients with BDR were younger (mean difference 7 years), with a greater proportion of females (52 vs 32%), underweight (15 vs 4%) and current smokers (52 vs 25%). Indigenous patients with BDR displayed lower LFT values, and a higher proportion exhibited FVC BDR compared to non-Indigenous (34 vs 20%). Almost half (46%) of Indigenous patients with BDR had evidence of COPD and/or bronchiectasis on radiology. Adjusting for the presence of radiologic or spirometric evidence of COPD, the presence of BDR was similar between Indigenous and non-Indigenous patients (5– 8 vs 7– 11%), irrespective of which BDR criteria was used.Conclusion: BDR was higher overall among Indigenous in comparison to non-Indigenous patients; however, a significant proportion of Indigenous patients demonstrating BDR had evidence of underlying COPD/bronchiectasis. This study highlights that although presence of BDR among Indigenous people may indicate asthma, it may also be observed among patients with COPD/bronchiectasis or could represent asthma/COPD/bronchiectasis overlap. Hence, a combination of clinical history, LFT and radiology should be considered for precise diagnosis of lung disease in this population.Keywords: asthma, airway obstruction, first nations, radiology imaging, reversible airflow obstruction, spirometry

Dorothy FL Sze,1 Timothy P Howarth,2,3 Clair D Lake,4 Helmi Ben Saad,5,6 Subash S Heraganahally1,3,7 1Department of Respiratory and Sleep Medicine, Royal Darwin Hospital, Darwin, NT, Australia; 2College of Health and Human Sciences, Charles Darwin University, Darwin, NT, Australia; 3Darwin Respiratory and Sleep Health, Darwin Private Hospital, Darwin, NT, Australia; 4Pulmonary Function Laboratory, Royal Darwin Hospital, Darwin, NT, Australia; 5Laboratory of Physiology, Faculty of Medicine of Sousse, University of Sousse, Sousse, Tunisia; 6Research laboratory “Heart Failure, LR12SP09”, Farhat HACHED Hospital, Faculty of Medicine of Sousse, University of Sousse, Sousse, Tunisia; 7College of Medicine and Public Health, Flinders University, Adelaide, SA, AustraliaCorrespondence: Subash S Heraganahally, Department of Respiratory and Sleep Medicine, Royal Darwin Hospital, Darwin, NT, Australia, Tel +61-8-89228888, Fax +61-8-89206309, Email hssubhashcmc@hotmail.com; Subash.heraganahally@nt.gov.auBackground: Comparison of spirometry parameters between Indigenous and non-Indigenous patients with underlying chronic obstructive pulmonary disease (COPD) has been sparsely reported in the past. In this study, differences in the lung function parameters (LFPs), in particular spirometry values for forced vital capacity (FVC), forced expiratory volume in one second (FEV1) and FEV1/FVC ratio between Indigenous and non-Indigenous patients with COPD were assessed.Methods: In this retrospective study, Indigenous and non-Indigenous patients with a diagnosis of COPD between 2012– 2020 according to spirometry criteria (ie; post-bronchodilator (BD) FEV1/FVC < 0.7) were included. A further analysis was undertaken to compare the differences in the spirometry parameters, including lower limit of normal (LLN) values matching for age, sex, height and smoking status between these two diverse ethnic populations.Results: A total of 240/742 (32%) Indigenous and 873/4579 (19%) non-Indigenous patients were identified to fit the criteria for COPD. Indigenous patients were significantly younger (mean difference 9.9 years), with a greater proportion of females (50% vs 33%), underweight (20% vs 8%) and current smokers (47% vs 32%). Prior to matching, Indigenous patients’ post-BD percent predicted values for FVC, FEV1, and FEV1/FVC ratio were 17, 17%, and − 2 points lower (Hedges G measure of effect size large (0.91), large (0.87), and small (0.25), respectively). Among the matched cohort (111 Indigenous and non-Indigenous), Indigenous patients LFPs remained significantly lower, with a mean difference of 16%, 16%, and − 4, respectively (Hedges G large (0.94), large (0.92) and small (0.41), respectively). The differences persisted despite no significant differences in LLN values for these parameters.Conclusion: Indigenous Australian patients with COPD display a significantly different demographic and clinical profile than non-Indigenous patients. LFPs were significantly lower, which may or may not equate to greater severity of disease in the absence of normative predictive lung function reference values specific to this population.Keywords: chronic obstructive pulmonary disease, Global Initiative for Chronic Obstructive Lung Disease, First Nations, Indigenous, lung function test, spirometry

Subash S Heraganahally,1– 3 Tarun R Ponneri,2 Timothy P Howarth,3,4 Helmi Ben Saad5 1Department of Respiratory and Sleep Medicine, Royal Darwin Hospital, Darwin, NT, Australia; 2Northern Territory Medical Program - College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia; 3Darwin Respiratory and Sleep Health, Darwin Private Hospital, Darwin, NT, Australia; 4College of Health and Human Sciences, Charles Darwin University, Darwin, NT, Australia; 5Université de Sousse, Faculté de Médecine de Sousse, Hôpital Farhat HACHED de Sousse, Laboratoire de Recherche “LR12SP09” “Insuffisance cardiaque”, Sousse, TunisiaCorrespondence: Subash S HeraganahallyDepartment of Respiratory and Sleep Medicine, Royal Darwin Hospital, Darwin, NT, AustraliaTel +61 8-89228888; +61 8-89206306Fax +61 8-89206309Email hssubhashcmc@hotmail.comBackground: The trajectory of lung function decline among Indigenous patients with or without underlying chronic airway disease (COPD and concomitant bronchiectasis) and with use of inhaled pharmacotherapy, including inhaled corticosteroids (ICS), has not been reported in the past.Methods: Adult Indigenous Australian patients identified to have undergone at least two or more lung function tests (LFTs) between 2012 and 2020 were assessed for changes in the lung function parameters (LFPs) between the first and last recorded LFTs.Results: Of the total 1350 patients identified to have undergone LFTs, 965 were assessed to fulfil session quality, 115 (n=58 females) were eligible to be included with two or more LFTs. Among the 115 patients, 49% showed radiological evidence of airway diseases, and 77% were on airway directed inhaled pharmacotherapy. Median time between LFTs was 1.5 years (IQR 0.86,5.85), with no significant differences in LFPs noted between first and last LFT. Overall rate of change (mL/year) showed considerable variation for FVC (median − 37.55 mL/year [IQR − 159.88,92.67]) and FEV1 (− 18.74 mL/year [− 102.49,71.44]) with minimal change in FEV1/FVC (0.00 ratio/year [− 0.03,0.01]). When stratified by inhaled pharmacotherapy group, however, patients using ICS showed significantly greater rate of FEV1 decline (− 48.64 mL/year [− 110.18,62.5]) compared to those using pharmacotherapy with no ICS (15.46 mL/year [− 73.5,74.62]) and those using no pharmacotherapy (− 5.76 mL/year [− 63.19,67.34]) (p=0.022). Additionally, a greater proportion of these patients reached the threshold for excessive FEV1 decline (64%) compared to those using pharmacotherapy without ICS (44%) and those using no pharmacotherapy (52%).Conclusion: Decline in LFPs occurs commonly among adult Indigenous population, especially, excessive so among those using inhaled pharmacotherapy containing ICS.Keywords: Aboriginal, bronchiectasis, COPD, indigenous, inhaled corticosteroids, lung function test, ICS, LFT