Longitudinal lung function in urban firefighters: A group-based multi-trajectory modelling approach.

BACKGROUND AND OBJECTIVE: Urban firefighters are routinely exposed to both physical and chemical hazards that can negatively impact lung health, but it is unclear if firefighters experience accelerated decline in spirometry parameters due to chronic exposure and acute insults. This study aimed to describe sub-groups of firefighters with differing spirometry trajectories and examine the relationship between the identified trajectories and demographic, lifestyle and occupational characteristics. METHODS: Data from six waves of the Respiratory Function Measurement and Surveillance for South Australian Metropolitan Fire Service Study (2007-2019) were used to identify spirometry parameter z-score trajectories, using group-based multi-trajectory modelling (GBMTM). Analysis of variance and chi-square statistics were used to assess trajectory group differences in baseline self-reported demographic, lifestyle and occupational characteristics. RESULTS: In the 669 included firefighters, we identified five trajectories for the combination of Forced Expiratory Volume in the first second z-score (FEV1 z), Forced Vital Capacity z-score (FVCz) and the ratio of FEV1 and FVC z-score (FEV1 /FVCz). There were three stable trajectories of low, average and very high lung function and two declining trajectories of average and high lung function. Analysis of subgroup characteristics revealed no significant differences between expected and actual group proportions for the occupational characteristics of years of service and respiratory protection use. Significant differences were seen in respiratory health and body mass index. CONCLUSION: GBMTM defined distinct, plausible spirometry trajectory sub-groups. Firefighter longitudinal spirometry trajectory group membership was associated with BMI and respiratory disease or symptoms but not with self-reported smoking history or occupational factors.

Correction to: The long-term rate of change in lung function in urban professional firefighters: a systematic review.

Following publication of the original article [1], the authors flagged an error in Table 2; specifically, within the row beginning 'Aldrich et al. 2013' on page 11 of the article PDF.

The long-term rate of change in lung function in urban professional firefighters: a systematic review.

BACKGROUND: Despite the known occupational hazards, it is not yet clear whether long-term career firefighting leads to a greater rate of decline in lung function than would normally be expected, and how this rate of change is affected by firefighting exposures and other risk/protective factors. METHODS: A systematic search of online electronic databases was conducted to identify longitudinal studies reporting on the rate of change in the forced expiratory volume in one second (FEV1) of forced vital capacity (FVC). Included studies were critically appraised to determine their risk of bias using the Research Triangle Institute Item Bank (RTI-IB) on Risk of Bias and Precision of Observational Studies. RESULTS: Twenty-two studies were identified for inclusion, from four different countries, published between 1974 and 2016. Examined separately, studies were categorised by the type of firefighting exposure. Firefighters experienced variable rates of decline in lung function, which were particularly influenced by cigarette smoking. The influence of routine firefighting exposures is unclear and limited by the methods of measurement, while firefighters exposed to 'non-routine' severe exposures unanimously experienced accelerated declines. CONCLUSIONS: The data provided by longitudinal studies provide an unclear picture of how the rate of change in lung function of firefighters relates to routine exposures and how it compares to the rate of change expected in a working-age population. Non-smoking firefighters who routinely wear respiratory protection are more likely than otherwise to have a normal rate of decline in lung function. Exposure to catastrophic events significantly increases the rate of decline in firefighter lung function but there is limited evidence detailing the effect of routine firefighting. Future studies will benefit from more robust methods of measuring exposure. TRIAL REGISTRATION: International Prospective Register of Systematic Reviews (PROSPERO), registration number ( CRD42017058499 ).

Barriers and outcomes of an evidence-based approach to diagnosis and management of chronic obstructive pulmonary disease (COPD) in Australia: a qualitative study.

Background: Chronic obstructive pulmonary disease (COPD) is commonly managed in primary care but there is poor awareness of evidence-based guidelines and the quality and interpretation of spirometry is suboptimal. Objectives: The aims of this qualitative study were to explore how an intervention involving case finding and management of COPD was implemented, and the extent to which the GPs and practice nurses (PNs) worked in partnership to diagnose and manage COPD. Methods: Semi-structured interviews with PNs (n = 7), GPs (n = 4) and patients (n = 26) who had participated in the Primary care EarLy Intervention for Copd mANagement (PELICAN) study. The Theoretical Domains Framework was used to guide the coding and analysis of the interviews with PN and GPs. The patient interviews were analysed thematically. Results: PNs developed technical skills and understood the requirements for good-quality spirometry. However, many lacked confidence in its interpretation and felt this was not part of their professional role. This was reflected in responses from the GPs. Once COPD was diagnosed, the GPs tended to manage the patients with the PNs less involved. This was in contrast with PNs' active role in managing patients with other chronic diseases such as diabetes. The extent to which the GPs and PNs worked in partnership to manage COPD varied. Conclusions: PNs improved their skills and confidence in performing spirometry. Beliefs about their professional role, identity and confidence influenced the extent to which PNs were involved in interpretation of the spirometry results and managing the patient in partnership with the GP.

Early intervention for chronic obstructive pulmonary disease by practice nurse and GP teams: a cluster randomized trial.

BACKGROUND: Early detection and intervention for chronic obstructive pulmonary disease (COPD) could potentially slow disease progress and minimize harm. OBJECTIVES: To assess the effectiveness of early intervention by a practice nurse-GP team on quality of life (QoL) and process of care in patients with newly diagnosed COPD, compared with usual care. Nurses and GPs in intervention practices were educated to develop and implement disease management plans for COPD. METHODS: A 12-month, multicentre, pragmatic randomized controlled trial with blinded outcome assessment was conducted. Participants were current and former smokers aged 40 to 85 years newly identified as having COPD on post-bronchodilator spirometry. The primary outcome was health-related QoL, assessed with the St George's Respiratory Questionnaire (SGRQ). Secondary outcome measures were other QoL measures, lung function, disease knowledge, smoking and immunization status, inhaler technique and health service use. RESULTS: Of the 10 234 patients from 36 practices in Sydney invited to a case-finding appointment, 1641 (16%) attended and 287 (18%) were diagnosed with COPD. Nineteen practices (144 patients) were randomized to the intervention group and 17 practices (110 patients) to the control group. Only 15.3% (n = 22) patients in the intervention group saw the nurse for COPD care following case finding. There was no between-group difference in SGRQ score at follow-up (mean difference -0.21; P = 0.86). Influenza vaccination was higher in the intervention group (OR 2.31: P = 0.035), but there were no other significant between-group differences in outcomes. CONCLUSION: Intervention uptake was low and had no additional beneficial effect, over usual care, on participants' health-related QoL.

Mucolytics for bronchiectasis.

BACKGROUND: Bronchiectasis is predominantly an acquired disease process that represents the end stage of a variety of unrelated pulmonary insults. It is defined as persistent irreversible dilatation and distortion of medium-sized bronchi. It has been suggested that with widespread use of high-resolution computed tomography, more bronchiectasis diagnoses are being made. Patients diagnosed with bronchiectasis frequently have difficulty expectorating sputum. Sputum therefore is retained in the lungs and may become infected, leading to further lung damage. Mucolytic agents target hypersecretion or changed physiochemical properties of sputum to make it easier to clear. One drug, recombinant human DNase, breaks down the DNA that is released at the site of infection by neutrophils.Mucus clearance along with antimicrobial therapy remains an integral part of bronchiectasis management. Chest physiotherapy along with mucolytic agents is commonly used in practice without clear supportive evidence. OBJECTIVES: To determine whether ingested or inhaled mucolytics are effective in the treatment of patients with bronchiectasis. SEARCH METHODS: We searched the Cochrane Airways Group Specialised Register and reference lists of relevant articles. We contacted experts in the field and drug companies. Searches were current as of June 2013. SELECTION CRITERIA: Randomised trials of mucolytic treatment in people with bronchiectasis but not cystic fibrosis. DATA COLLECTION AND ANALYSIS: Data extraction was performed independently by two review authors. Study authors were contacted for confirmation. MAIN RESULTS: Four trials (with a combined total of 528 adult participants) were included, but almost none of the data from these studies could be aggregated in a meta-analysis.One trial (with 88 participants) compared bromhexine versus placebo. Compared with placebo, high doses of bromhexine with antibiotics eased difficulty in expectoration (mean difference (MD) -0.53, 95% confidence interval (CI) -0.81 to -0.25 at 16 days); the quality of the evidence was rated as low. A reduction in sputum production was noted with bromhexine (MD -21.5%, 95% CI -38.9 to -4.1 at day 16); again the quality of the evidence was rated as low. No significant differences between bromhexine and placebo were observed with respect to reported adverse events (odds ratio (OR) 2.93; 95% CI 0.12 to 73.97), and again the quality of the evidence was rated as low.In a single small, blinded but not placebo-controlled trial of older (> 55 years) participants with stable bronchiectasis and mucus hypersecretion, erdosteine combined with physiotherapy over a 15-day period improved spirometry and sputum purulence more effectively compared with physiotherapy alone. The spirometric improvement was small (MD 200 mL in forced expiratory volume in one second (FEV1) and 300 mL in forced vital capacity (FVC)) and was apparent only at day 15, not at earlier time points.The remaining two studies (with a combined total of 410 participants) compared recombinant human DNase (RhDNase) versus placebo. These two studies were very different (one was a two-week study of 61 participants, and the other ran for 24 weeks and included 349 participants), and the opportunity for combining data from the two studies was very limited. Compared with placebo, recombinant human DNase showed no difference in FEV1 or FVC in the smaller study but showed a significant negative effect on FEV1 in the larger and longer study. For reported adverse events, no significant differences between recombinant human DNase and placebo were noted. In all of the above comparisons of recombinant human DNase versus placebo, the quality of the evidence was judged to be low. AUTHORS' CONCLUSIONS: Given the harmful effects of recombinant human DNase in one trial and no evidence of benefit, this drug should be avoided in non-cystic fibrosis bronchiectasis, except in the context of clinical trials. Evidence is insufficient to permit evaluation of the routine use of other mucolytics for bronchiectasis. High doses of bromhexine coupled with antibiotics may help with sputum production and clearance, but long-term data and robust clinical outcomes are lacking. Similarly, erdosteine may be a useful adjunct to physiotherapy in stable patients with mucus hypersecretion, but robust longer-term trials are required.Generally, clinical trials in children on the use of various mucolytic agents are lacking. As the number of agents available on the market, such as RhDNase, acetylcysteine and bromhexine, is increasing, improvement of the evidence base is needed.

Chronic respiratory conditions in a cohort of metropolitan fire-fighters: associations with occupational exposure and quality of life.

OBJECTIVES: To assess the prevalence of chronic respiratory conditions in metropolitan fire-fighters and to study associations between occupational exposure, use of respiratory protection and health-related quality of life (HRQoL) in fire-fighters with and without chronic respiratory conditions. METHODS: Cross-sectional cohort analysis: Respiratory symptoms, medical conditions, occupational tasks and exposures and consistency of using respiratory protection were inquired by questionnaire. The SF12(®)V2 Health Survey was used to measure physical (PCS-12) and mental (MCS-12) HRQoL. Fire-fighters were categorised in subgroups: asthma; COPD/emphysema/chronic bronchitis; no chronic respiratory conditions; and as being 'not involved' or 'involved' in fire-fighting tasks, the latter further categorised as 'consistent' or 'inconsistent' use of respiratory protection. PCS-12 and MCS-12 scores were compared between subgroups and categories using linear regression. RESULTS: Five hundred and seventy fire-fighters were analysed, 24 (4%) fulfilled the criteria for asthma, 39 (7%) for COPD/emphysema/chronic bronchitis. Fire-fighters with asthma were older than those in the other two subgroups and had been employed in the fire service longer. Respiratory subgroups did not differ in their involvement in fire-fighting tasks. Ninety-one percent of fire-fighters reported relevant occupational exposure in the past year. Mean PCS-12 scores for fire-fighters with no chronic respiratory conditions, asthma and COPD/emphysema/bronchitis were 52.0 (SD 6.9), 47.0 (8.5) and 48.1 (9.4). For PCS-12 (but not for MCS-12), interaction between having a chronic respiratory condition and inconsistent use of respiratory protection during fire knockdown was observed (p < 0.001). CONCLUSIONS: Ten percent of metropolitan fire-fighters reported underlying chronic respiratory conditions. Presence of such a condition in combination with suboptimal protection from inhaled exposures may lead to poorer physical HRQoL.

Validation of the COPD Diagnostic Questionnaire in an Australian general practice cohort: a cross-sectional study.

BACKGROUND: The gold standard for the diagnosis of chronic obstructive pulmonary disease (COPD) is spirometry, but there are barriers to its use in primary care. AIMS: To externally validate the COPD Diagnostic Questionnaire (CDQ) as a diagnostic tool in patients at increased risk in Australian general practice and to compare its performance with other CDQ validation studies. METHODS: Patients were recruited from 36 general practices in Sydney, Australia. Former or current smokers aged 40-85 years with no prior COPD diagnosis were invited to a case-finding appointment with the practice nurse. The CDQ was collected and pre- and postbronchodilator spirometry was performed. Cases for whom complete CDQ data were present and the spirometry met quality standards were analysed. RESULTS: Of 1,631 patients who attended case-finding recruitment, 1,054 (65%) could be analysed. Spirometry showed 13% had COPD. The ability of the CDQ to discriminate between patients with and without COPD was fair, represented by the area under the receiver operating characteristic curve of 0.713. With a CDQ cut-off point value of 16.5 the sensitivity was 80% and specificity 47% and, at a cut-off point value of 19.5, the sensitivity was 63% and specificity 70%. CONCLUSIONS: The CDQ did not discriminate between patients with and without COPD accurately enough to use as a diagnostic tool in patients at increased risk of COPD in Australian general practice. Further research is needed on the value of the CDQ as a tool for selecting patients for spirometry.

Perceptions of lung function surveillance in urban firefighters.

BACKGROUND AND OBJECTIVE: Workplace health and safety (WHS) is an important responsibility falling on both employers and employees and is most effective when the perspectives of all stakeholders are considered. This study aimed to explore the facilitators and barriers to a voluntary workplace lung function surveillance program from the perspective of urban firefighters and describe their perceptions of its value. METHODS: Using a qualitative, descriptive methodology, firefighters who had participated in a longitudinal lung function surveillance study were invited to participate in semi-structured interviews. Purposeful, maximum variation sampling was used to achieve diversity in those firefighters invited to participate. We used inductive content analysis to identify themes. RESULTS: Interviews with 15 firefighters identified 3 main themes: (i) practical experience of surveillance (administration, communication, workplace culture change, convenience, acceptability, and appeal); (ii) value of surveillance (lung health efficacy and control, social support, workplace management support/motivations, contribution to global firefighter health); and (iii) contribution of surveillance to health (occupational risk, relevance in the context of total health, workability, and fitness and future value). CONCLUSION: Practical and psychosocial facilitators and barriers to providing lung function surveillance in the fire service were identified. In addition to the personal benefits of detecting adverse lung health and allowing for medical intervention, factors known to positively influence firefighter workplace wellbeing, such as providing peace of mind, feedback on good work practices, motivation to utilize control measures, management commitment to health, and providing data to assist with global knowledge were valued aspects of longitudinal lung function surveillance.

Accuracy and precision of desktop spirometers in general practices.

BACKGROUND: Spirometry has become an essential tool for general practices to diagnose and monitor chronic airways diseases, but very little is known about the performance of the spirometry equipment that is being used in general practice settings. The use of invalid spirometry equipment may have consequences on disease diagnosis and management of patients. OBJECTIVES: To establish the accuracy and precision of desktop spirometers that are routinely used in general practices. METHODS: We evaluated a random sample of 50 spirometers from Dutch general practices by testing them on a certified waveform generator using 8 standard American Thoracic Society waveforms to determine accuracy and precision. Details about the brand and type of spirometers, year of purchase, frequency of use, cleaning and calibration were inquired with a study-specific questionnaire. RESULTS: 39 devices (80%) were turbine spirometers, 8 (16%) were pneumotachographs, and 1 (2%) was a volume displacement spirometer. Mean age of the spirometers was 4.3 (SD 3.7) years. Average deviation from the waveform generator reference values (accuracy) was 25 ml (95% confidence interval 12-39 ml) for FEV(1) and 27 ml (10-45 ml) for FVC, but some devices showed substantial deviations. FEV(1) deviations were larger for pneumotachographs than for turbine spirometers (p < 0.0031), but FVC deviations did not differ between the two types of spirometers. In the subset of turbine spirometers, no association between age and device performance was observed. CONCLUSIONS: On average, desktop spirometers in general practices slightly overestimated FEV(1) and FVC values, but some devices showed substantial deviations. General practices should pay more attention to the calibration of their spirometer.

Newer equations better predict lung age in smokers: a retrospective analysis using a cohort of randomly selected participants.

AIMS: To produce new lung age equations using four previously published predictive equations for forced expiratory volume in 1 second and to compare them with lung age equations published in 1985 and 2010. METHODS: Initial comparisons used phantom subjects of different ages and levels of lung function. Comparison of lung age equations by regression analysis used an independent dataset of 3,206 randomly selected community-dwelling adults aged >18 years in the North West Adelaide Health Study. RESULTS: The more recent equations estimated lung age as greater than chronological age as lung function decreased, whereas the oldest equations estimated lung age as less than chronological age until lung function was severely limited. Significant differences (p<0.001) were detected by regression analysis, with four newer lung age equations being significantly different from the 1985 equation and one being no different. CONCLUSIONS: Lung age estimates using six predictive equations spanning 50 years show differences attributable to cohort and period effects. This reinforces the need for regular updating of predictive equations for lung function. These results further confirm the need to use modern lung age equations which will provide a stronger message in smoking cessation counselling.

Microbiological contamination of spirometers - an exploratory study in general practice.

BACKGROUND: Spirometry is an important tool when diagnosing chronic respiratory conditions in general practice. However, the equipment may harbour pathogenic micro-organisms and cross-transmission of aerolised pathogens could occur if hygiene measures are insufficient. METHODS: We assessed microbiological contamination in 16 spirometers from a convenience sample of South Australian general practices. Results We found potentially relevant microbiological contamination in three spirometers: two Pseudomonas spp.; one coagulase negative Staphylococcus sp. and one Alcaligenes sp. Although the three practices concerned all reported to have a written spirometer cleaning protocol in place, the frequency of spirometer disinfection did not match the manufacturers' DISCUSSION: Despite the small size of our study sample, we found potentially relevant microbiological contamination in 3 out of 16 spirometers from metropolitan general practices. The potential hazard of spirometers as reservoirs of microorganisms stresses the need for stricter attention to hygiene measures for spirometer maintenance in general practices.

Effect of palliative oxygen versus room air in relief of breathlessness in patients with refractory dyspnoea: a double-blind, randomised controlled trial.

BACKGROUND: Palliative oxygen therapy is widely used for treatment of dyspnoea in individuals with life-limiting illness who are ineligible for long-term oxygen therapy. We assessed the effectiveness of oxygen compared with room air delivered by nasal cannula for relief of breathlessness in this population of patients. METHODS: Adults from outpatient clinics at nine sites in Australia, the USA, and the UK were eligible for enrolment in this double-blind, randomised controlled trial if they had life-limiting illness, refractory dyspnoea, and partial pressure of oxygen in arterial blood (PaO(2)) more than 7.3 kPa. Participants were randomly assigned in a 1:1 ratio by a central computer-generated system to receive oxygen or room air via a concentrator through a nasal cannula at 2 L per min for 7 days. Participants were instructed to use the concentrator for at least 15 h per day. The randomisation sequence was stratified by baseline PaO(2) with balanced blocks of four patients. The primary outcome measure was breathlessness (0-10 numerical rating scale [NRS]), measured twice a day (morning and evening). All randomised patients who completed an assessment were included in the primary analysis for that data point (no data were imputed). This study is registered, numbers NCT00327873 and ISRCTN67448752. FINDINGS: 239 participants were randomly assigned to treatment (oxygen, n=120; room air, n=119). 112 (93%) patients assigned to receive oxygen and 99 (83%) assigned to receive room air completed all 7 days of assessments. From baseline to day 6, mean morning breathlessness changed by -0.9 points (95% CI -1.3 to -0.5) in patients assigned to receive oxygen and by -0.7 points (-1.2 to -0.2) in patients assigned to receive room air (p=0.504). Mean evening breathlessness changed by -0.3 points (-0.7 to 0.1) in the oxygen group and by -0.5 (-0.9 to -0.1) in the room air group (p=0.554). The frequency of side-effects did not differ between groups. Extreme drowsiness was reported by 12 (10%) of 116 patients assigned to receive oxygen compared with 14 (13%) of 108 patients assigned to receive room air. Two (2%) patients in the oxygen group reported extreme symptoms of nasal irritation compared with seven (6%) in the room air group. One patient reported an extremely troublesome nose bleed (oxygen group). INTERPRETATION: Since oxygen delivered by a nasal cannula provides no additional symptomatic benefit for relief of refractory dyspnoea in patients with life-limiting illness compared with room air, less burdensome strategies should be considered after brief assessment of the effect of oxygen therapy on the individual patient. FUNDING: US National Institutes of Health, Australian National Health and Medical Research Council, Duke Institute for Care at the End of Life, and Doris Duke Charitable Foundation.

Effect of e-learning and repeated performance feedback on spirometry test quality in family practice: a cluster trial.

PURPOSE: Spirometry has become an indispensable tool in primary care to exclude, diagnose, and monitor chronic respiratory conditions, but the quality of spirometry tests in family practices is a reason for concern. Aim of this study was to investigate whether a combination of e-learning and bimonthly performance feedback would improve spirometry test quality in family practices in the course of 1 year. METHODS: Our study was a cluster trial with 19 family practices allocated to intervention or control conditions through minimization. Intervention consisted of e-learning and bimonthly feedback reports to practice nurses. Control practices received only the joint baseline workshop. Spirometry quality was assessed by independent lung function technicians. Two outcomes were defined, with the difference between rates of tests with 2 acceptable and repeatable blows being the primary outcome and the difference between rates of tests with 2 acceptable blows being the secondary outcome. We used multilevel logistic regression analysis to calculate odds ratios (ORs) for an adequate test in intervention group practices. RESULTS: We analyzed 1,135 tests. Rate of adequate tests was 33% in intervention and 30% in control group practices (OR = 1.3; P=.605). Adequacy of tests did not differ between groups but tended to increase with time: OR = 2.2 (P = .057) after 3 and OR = 2.0 (P = .086) in intervention group practices after 4 feedback reports. When ignoring test repeatability, these differences between the groups were slightly more pronounced: OR = 2.4 (P = .033) after 3 and OR=2.2 (P = .051) after 4 feedback reports. CONCLUSIONS: In the course of 1 year, we observed a small and late effect of e-learning and repeated feedback on the quality of spirometry as performed by family practice nurses. This intervention does not seem to compensate the lack of rigorous training and experience in performing spirometry tests in most practices.

Vitamin D insufficiency in Aboriginal Australians.

OBJECTIVE: To investigate the adequacy of vitamin D status in a South Australian Aboriginal population, and to examine the relationship between serum 25-hydroxyvitamin D (25-OHD) levels and biochemical variables of calcium and bone mineral homeostasis, as well as other factors which may influence vitamin D synthesis, storage and metabolism. DESIGN, SETTING AND PARTICIPANTS: A single-visit, observational study of 58 adults from two Aboriginal community-controlled health services in Adelaide and Yalata, South Australia. Participants were recruited between May 2008 and December 2009. MAIN OUTCOME MEASURES: Serum levels of 25-OHD, parathyroid hormone (PTH), fasting glucose and fasting C-terminal telopeptides of type I collagen (ß-CTx). RESULTS: Serum 25-OHD levels showed clear seasonal variation, being higher in summer (P < 0.001). The overall mean level was 56.8 nmol/L (SD, 22.1), which is below the recommended target level of 60 nmol/L. Serum 25-OHD levels correlated significantly with ß-CTx (P = 0.03), but not with age, body mass index (BMI), PTH levels or levels of fasting glucose. A significant association was found between BMI and PTH levels (P = 0.001). A significant inverse association between serum 25-OHD levels and BMI, observed in other studies, was not found in our study. CONCLUSIONS: Vitamin D insufficiency is highly prevalent in this population of adult Aboriginal Australians, with low mean values found in all seasons other than summer.

Does spirometry training in general practice improve quality and outcomes of asthma care?

OBJECTIVE: Clinical asthma guidelines recommend spirometry for asthma diagnosis, but there is inconsistent evidence about benefits to patients in using it for ongoing management. Our aim was to determine whether training in the use of spirometry for management of asthma provided better health outcomes and improved the quality of care in the primary care setting. DESIGN: Pragmatic, cluster randomized controlled trial. SETTING: General practices in two states of Australia. PARTICIPANTS: Forty practices and 397 adults with asthma. INTERVENTION: The staff of 26 intervention practices received comprehensive spirometry training. Fourteen control practices provided usual care. MAIN OUTCOME MEASURES: Primary outcome measures were quality of life, self-reported asthma symptoms and lung function. Secondary measures related to the process of care (e.g. performance of spirometry, preparation of a written asthma action plan) and patient and general practitioner rating of the acceptability and usefulness of spirometry. RESULTS: There were no statistically significant differences between the groups at 12 months for quality of life (mean difference = -0.23; 95% CI: -0.44, -0.01), days off work (rate ratio = 1.52; 95% CI: 0.91, 2.54), exacerbations (rate ratio = 1.09; 95% CI: 0.85, 1.41), asthma on waking (rate ratio = 1.21; 95% CI: 0.79, 1.85), nocturnal asthma (rate ratio = 0.98; 95% CI: 0.63, 1.51) and post-bronchodilator FEV(1)/FVC ratio (mean difference = -0.01, 95% CI: -0.03, 0.02). There was no improvement in the quality of care provided. CONCLUSIONS: Training in spirometry did not result in any measurable improvement in the use of spirometry, quality of management of asthma or patient outcomes in primary care.

Simplified COPD screening: validation of the PiKo-6® in primary care.

AIMS: To determine the accuracy of the forced expiratory volume ratio at one and six seconds (FEV1/FEV6) using a hand-held, expiratory flow meter (PiKo-6®, nSpire Health, Inc.) to screen for chronic obstructive pulmonary disease (COPD) in primary care settings. METHODS: Current and former smokers (≥ 50 years old) with no previous respiratory diagnosis (case finding [CF] = 204 subjects) or with an asthma diagnosis (differential diagnosis [DD] = 93 subjects) were evaluated using validated questionnaires, pre-bronchodilator (BD) FEV1/FEV6 and post-BD FEV1/forced vital capacity (FVC) spirometry. RESULTS: The PiKo-6® FEV1/FEV6 showed good sensitivity and specificity (areas under the Receiver Operating Characteristic curves [95% confidence intervals]: CF = 0.85 [0.79, 0.90]; DD = 0.88 [0.80, 0.96]) and exceeded the accuracy of the questionnaires. An FEV1/FEV6 cutoff < 0.75 provided optimal sensitivity (CF = 81%; DD = 86%) and specificity (CF = 71%; DD = 67%) for COPD screening. CONCLUSIONS: The PiKo-6® allows simple and reliable screening for COPD which could optimise early referral for spirometry and early, targeted interventions for COPD.

Spirometry and impulse oscillometry (IOS) for detection of respiratory abnormalities in metropolitan firefighters.

BACKGROUND AND OBJECTIVE: As firefighters are at increased risk of adverse health effects, periodic examination of their respiratory health is important. The objective of this study was to establish whether the use of impulse oscillometry (IOS) reveals respiratory abnormalities in metropolitan firefighters that go undetected during routine respiratory health screening by spirometry and assessment of respiratory symptoms. METHODS: This was a cross-sectional analysis of spirometry, IOS and questionnaire data from 488 male firefighters. Abnormal spirometry was defined as FEV(1), FEV(1)/FVC and/or FEF(50) below the lower limit of normal. Abnormal IOS was defined as resistance at 5 Hz (R5), frequency dependence of resistance (DeltaR5-R20) and/or reactance area (AX) above the upper limit of normal. Respiratory symptoms, smoking history, exposures and medical history were assessed. Data were analysed using logistic and linear regression models. RESULTS: The mean age of the firefighters was 43.8 (SD 8.4) years. There were 123 (25%) former smokers and 50 (10%) current smokers. Abnormal spirometry was detected in 12%, abnormal IOS in 9% and respiratory symptoms in 20% of firefighters. Current smoking was associated with all IOS parameters (OR for R5 = 3.1, OR for DeltaR5-R20 = 7.7, OR for AX = 4.3), and with FEF(50) (OR = 9.1), chronic productive cough (OR = 4.0) and breathlessness (OR = 5.4) (P < 0.05 for all). Exposure during firefighting duties was associated with chronic productive cough (OR = 2.6), but not with spirometry or IOS parameters. Interaction terms in the linear regression models indicated associations between smoking and DeltaR5-R20, and also between smoking and AX, in the lowest and second lowest quartiles of spirometry parameters. CONCLUSIONS: Application of IOS for the assessment of respiratory health in firefighters identified airways dysfunction in some individuals, even when spirometry values were within the normal range and there were no respiratory symptoms.

Lung function and health status in metropolitan fire-fighters compared to general population controls.

PURPOSE: To assess health status of South Australian (SA) metropolitan fire-fighters in terms of lung function and health-related quality of life, compare these with general population controls, and explore associations between fire-fighters' self-reported occupational exposure and health status. METHODS: The study was a cross-sectional comparison of (respiratory) health indices between 501 fire-fighters and 1,324 general population controls taken from the North West Adelaide Health Study (NWAHS). All were men aged 21 to 61. Measurements included spirometry (i.e., forced expiratory volume in 1 s (FEV(1)), forced vital capacity (FVC), mid-expiratory flow (FEF(25-75)) and the Short Form 36 (SF-36) health-related quality of life questionnaire. RESULTS: Health status in the fire-fighters was generally better than in NWAHS controls. Mean % predicted FEV(1) and FVC were 103.4% [SD 12.1] versus 89.5% [13.7] and 110.0% [11.6] versus 88.5% [12.5] (both p < 0.001 in linear regression analysis, adjusted for age, smoking, BMI, and FEV(1) % predicted). FEV(1)/FVC and FEF(25-75) were significantly lower in the fire-fighters (p < 0.003). A total of 93 (18.6%) fire-fighters and 82 (6.2%) controls had an FEV(1)/FVC < 70% (p < 0.001). The SF-36 Mental Health scale was the only scale on which fire-fighters had a lower mean score (p = 0.009), but none of the SF-36 scales showed clinically meaningful differences between the cohorts. Fire-fighters exposed > 6 h/week to dust, smoke, and fire showed lower FEV(1), FEV(1) % predicted, and FVC values compared to those who were less exposed (p < 0.05). CONCLUSIONS: Male metropolitan fire-fighters showed better general health, better lung health, and similar mental health compared to general population controls. The high rate of fire-fighters with FEV(1)/FVC values below the recommended cut-point for airflow obstruction illustrates the inappropriateness of this clinical cut-point for use in populations preselected on their physical fitness. The observed dose-effect relationship between self-reported occupational exposure and fire-fighters' lung function warrants further investigation.

Exploring the need to update lung age equations.

AIMS: A renewed interest in lung age is evidenced by recent smoking cessation publications. This research compares the original Morris lung age equations (1985) with contemporary Australian lung age equations. METHODS: Both lung age equations were applied to the spirometry results of two sub-groups (never-smokers n=340, and current smokers n=50) from an independent dataset. Means of both lung age estimates were compared to the mean of the chronological age of each group by paired Student's t-test. RESULTS: The Morris lung age estimates were paradoxically lower (younger) than chronological age in both groups. The new Australian equation produced lung age estimates that were equivalent to chronological age in the never-smoker group and significantly higher (older) than chronological age in the current smoker group. CONCLUSIONS: These results strongly suggest that the Morris lung age equations are in need of review. The use of contemporary lung age equations may translate into greater success for smoking cessation programs. The new Australian equations seem to possess internal validity.