Sex differences in pulmonary function parameters among Indigenous Australians with and without chronic airway disease

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.

Chest computed tomography findings among adult Indigenous Australians in the Northern Territory of Australia

INTRODUCTION

There is sparse evidence in the literature in relation to the chest computed tomography (CT) findings among adult Indigenous Australians with chronic respiratory conditions.

METHODS

In this retrospective study, patients who underwent chest CT between 2012 and 2020 among those referred to undergo lung function tests (spirometry) were assessed for the prevalence of abnormal chest CT radiological findings.

RESULTS

Of the 402 patients (59% female) included in this study, 331 (82%) had an abnormality identified on chest CT. Most abnormalities occurred alongside one (25%) or multiple (46%) other CT abnormalities. Airway disease ((AD) (including, emphysema, airway wall thickening and small airway disease) (35%), atelectasis: segmental or lobar collapse (27%), inflammatory opacities (24%) and bronchiectasis (23%) were the most common findings. AD and bronchiectasis were also the most common concurrent abnormalities in 40-50%. Other CT abnormalities noted in isolation or in combination with other CT findings were lung nodules (19%), lymph node enlargement (17%), consolidation or mass (17%), followed by lung cysts, ground-glass opacity, lung parenchymal architectural distortion, cavitating lung lesions and chronic pleural effusion were observed in ≤10%. Predictive models for odds of abnormality and outcomes showed age, smoking and underweight were associated with AD, and male sex and very remote residence were associated with bronchiectasis.

CONCLUSION

This study has illustrated that Indigenous Australian adults have a high prevalence of multiple chest CT abnormalities that may impose unprecedented diagnostic and therapeutic challenges in this population. Further studies are warranted to determine the long-term implications and prognostic significance of the CT findings as demonstrated in this study.

Critical analysis of spirometric patterns in correlation to chest computed tomography among adult Indigenous Australians with chronic airway diseases

Background: There is sparse literature evidence in the spirometric patterns of adult Indigenous Australians with and without chest computed tomography (CT)-proven chronic airway diseases (CADs).Methods: Participants spirometry testing graded as acceptable for quality and had a chest CT scan showing radiographic evidence of CADs were included for analysis.Results: Of the 1350 spirometric tests performed between 2012 and 2020, a total of 212 patients with a mean age of 53 years and 54% females were eligible to be included. One-third (30%) had normal chest CT (without CADs), 35% had predominant COPD, 19% bronchiectasis and 16% combined COPD and bronchiectasis. Percentage predicted values for forced vital capacity (FVC) and forced expiratory volume in one second (FEV₁) both pre- and post- bronchodilator were significantly reduced for all participants - FVC: CT-normal 64%, 65%; COPD 58%, 62%; bronchiectasis 54%, 54%; combined COPD and bronchiectasis 50%, 53%. FEV₁: CT-normal 62%, 65%; COPD 46%, 49%; bronchiectasis 48%,51%; combined COPD and bronchiectasis 36%,40%. FEV₁/FVC was only reduced for CT abnormality patients - CT-normal 96%,98%; COPD 77%,77%; bronchiectasis 87%,89%; combined COPD and bronchiectasis 71%,72%.Conclusions: Restrictive spirometric pattern is common and an obstructive pattern with COPD, in isolation or when COPD coexists with bronchiectasis.

Lung function parameters among Australian Aboriginal 'apparently healthy' adults: an Australian Caucasian and Global Lung Function Initiative (GLI-2012) various ethnic norms comparative study

Background: There is sparse literature evidence evaluating the applicability of the GLI-2012 spirometric norms for Australian Aboriginal adults.Methods: Lung function parameters (LFPs) were compared between Australian Aboriginal and Australian Caucasians, and the fit of Australian Aboriginals LFPs with various ethnic GLI equations was tested.Results: Of 1350 and 5634 Pulmonary function tests (PFTs) in Australian Aboriginal and Australian Caucasian adults, 153 and 208 PFTs matched for anthropometrics and normal chest radiology, respectively. Absolute FVC and FEV₁ values were 20% lower in Australian Aboriginals compared to Australian Caucasians. Differences remained significant after accounting for age, sex, height, weight and smoking status in multivariate regression (FVC -0.84 L (-0.98, -0.71), FEV₁ - 0.72 L (-0.84, -0.59), but with nearly preserved FEV₁/FVC. GLI-2012 transformation resulted in z-scores significantly below zero for each of FVC, FEV₁ and FEV₁/FVC with z-scores ranging from -4.52 (-4.87, -4.16) for North East Asian FVC transformation for males, to -0.34 (-0.73, 0.05) for Black FVC transformation for females.Conclusions: Australian Aboriginal adults had 20% lower values for FVC and FEV₁ but nearly preserved absolute FEV₁/FVC in comparison to Australian Caucasians. The GLI-2012 spirometric norms do not appear to fit for Australian Aboriginal adults regardless of which ethnicity options selected, including 'others/mixed'.

The squatting position for the second stage of labor: effects on labor and on maternal and fetal well-being

A cohort study was designed to assess the effects of maternal squatting position for the second stage of labor on the evolution and progress of labor, and on maternal and fetal well-being. Outcomes from 200 squatting births, randomly selected from a sample of 1000, were compared with 100 semirecumbent births, randomly selected from a sample of 300. Data collection was by chart review. The two groups were similar with respect to most antepartal, intrapartal, and socioeconomic variables likely to affect labor outcomes. The mean length of the second stage of labor was 23 minutes shorter in squatting primiparas and 13 minutes shorter in squatting multiparas than in semirecumbent women. Squatting women required significantly less labor stimulation by oxytocin during second stage (P = 0.0016), and they showed a trend toward fewer mechanically assisted deliveries. Significantly fewer and less severe perineal lacerations occurred, and fewer episiotomies were performed in the squatting group (P = 0.0001). No statistically significant differences were found between groups for third-stage complications and infant complications.

Assessment of hypothalamic-pituitary-adrenal (HPA) axis dysfunction: comparison of ACTH stimulation, insulin-hypoglycemia and metyrapone

The response to ACTH stimulation, insulin-hypoglycemia and metyrapone in patients with suspected HPA axis dysfunction due to corticosteroid therapy (Group I, n = 10), or pituitary surgery (Group II, n = 7) and in a control population (Group III, n = 8) was studied. Group I patients had been maintained on a stable low dose of prednisone 5.0-7.5 mg/day for 1 month-16 yr (mean = 31 mos) prior to testing. Basal 08:00 h cortisol levels in this group were not different from control values. However, the mean responses to all three testing procedures were suppressed (Group I vs III, ACTH p less than 0.001, insulin p less than 0.01, metyrapone p less than 0.05). Group II patients had undergone surgery 1-26 months (mean = 10 mo) prior to testing and had been maintained subsequently on a stable dose of prednisone 5.0-7.5 mg/day. In this group basal mean 08:00 h cortisol and the cortisol response to ACTH and insulin-hypoglycemia were not significantly different from control values while the response to metyrapone was suppressed (Group II vs III p less than 0.02). Basal serum DHEA-S levels were suppressed in both Groups I and II when compared to Group III (p less than 0.001). Discordant responses to the three testing procedures were noted in 6 patients with suspected HPA dysfunction with abnormal test results in 1/6 using cortrosyn, 3/6 using insulin-hypoglycemia and 4/6 using metyrapone.(ABSTRACT TRUNCATED AT 250 WORDS)