11 research outputs found
Association of respiratory symptoms and lung function with occupation in the multinational Burden of Obstructive Lung Disease (BOLD) study
Background
Chronic obstructive pulmonary disease has been associated with exposures in the workplace. We aimed to assess the association of respiratory symptoms and lung function with occupation in the Burden of Obstructive Lung Disease study.
Methods
We analysed cross-sectional data from 28 823 adults (≥40 years) in 34 countries. We considered 11 occupations and grouped them by likelihood of exposure to organic dusts, inorganic dusts and fumes. The association of chronic cough, chronic phlegm, wheeze, dyspnoea, forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1)/FVC with occupation was assessed, per study site, using multivariable regression. These estimates were then meta-analysed. Sensitivity analyses explored differences between sexes and gross national income.
Results
Overall, working in settings with potentially high exposure to dusts or fumes was associated with respiratory symptoms but not lung function differences. The most common occupation was farming. Compared to people not working in any of the 11 considered occupations, those who were farmers for ≥20 years were more likely to have chronic cough (OR 1.52, 95% CI 1.19–1.94), wheeze (OR 1.37, 95% CI 1.16–1.63) and dyspnoea (OR 1.83, 95% CI 1.53–2.20), but not lower FVC (β=0.02 L, 95% CI −0.02–0.06 L) or lower FEV1/FVC (β=0.04%, 95% CI −0.49–0.58%). Some findings differed by sex and gross national income.
Conclusion
At a population level, the occupational exposures considered in this study do not appear to be major determinants of differences in lung function, although they are associated with more respiratory symptoms. Because not all work settings were included in this study, respiratory surveillance should still be encouraged among high-risk dusty and fume job workers, especially in low- and middle-income countries.publishedVersio
Cohort Profile: Burden of Obstructive Lung Disease (BOLD) study
The Burden of Obstructive Lung Disease (BOLD) study was established to assess the prevalence of chronic airflow obstruction, a key characteristic of chronic obstructive pulmonary disease, and its risk factors in adults (≥40 years) from general populations across the world.
The baseline study was conducted between 2003 and 2016, in 41 sites across Africa, Asia, Europe, North America, the Caribbean and Oceania, and collected high-quality pre- and post-bronchodilator spirometry from 28 828 participants.
The follow-up study was conducted between 2019 and 2021, in 18 sites across Africa, Asia, Europe and the Caribbean. At baseline, there were in these sites 12 502 participants with high-quality spirometry. A total of 6452 were followed up, with 5936 completing the study core questionnaire. Of these, 4044 also provided high-quality pre- and post-bronchodilator spirometry.
On both occasions, the core questionnaire covered information on respiratory symptoms, doctor diagnoses, health care use, medication use and ealth status, as well as potential risk factors. Information on occupation, environmental exposures and diet was also collected
Spirometry in Central Asian lowlanders and highlanders, a population based study
Introduction: The purpose of the study was to establish spirometric reference values for a Central Asian population of highlanders and lowlanders. Methods: Spirometries from a population-based cross-sectional study performed in 2013 in rural areas of Kyrgyzstan were analyzed. Using multivariable linear regression, Global Lung Function Initiative (GLI) equations were fitted separately for men and women, and altitude of residence (700-800 m, 1,900-2,800 m) to data from healthy, never-smoking Kyrgyz adults. The general GLI equation was applied: Predicted value = e a 0 + a 1 × ln ( Height ) + a 2 × ln ( Age ) + b 1 × ln ( Age 100 ) + b 2 × ln ( Age 100 ) 2 + b 3 × ln ( Age 100 ) 3 + b 4 × ln ( Age 100 ) 4 + b 5 × ln ( Age 100 ) 5 Results: Of 2,784 screened Kyrgyz, 448 healthy, non-smoking highlanders (379 females) and 505 lowlanders (368 females), aged 18-91 years, were included. Predicted FVC in Kyrgyz fit best with GLI "North-East Asians," predicted FEV1 fit best with GLI "Other/Mixed." Predicted FEV1/FVC was lower than that of all GLI categories. Age- and sex-adjusted mean FVC and FEV1 were higher in highlanders (+0.138l, +0.132l) than in lowlanders (P < 0.001, all comparisons), but FEV1/FVC was similar. Conclusion: We established prediction equations for an adult Central Asian population indicating that FVC is similar to GLI "North-East Asian" and FEV1/FVC is lower than in all other GLI population categories, consistent with a relatively smaller airway caliber. Central Asian highlanders have significantly greater dynamic lung volumes compared to lowlanders, which may be due to environmental and various other effects
Effect of Dexamethasone on Nocturnal Oxygenation in Lowlanders With Chronic Obstructive Pulmonary Disease Traveling to 3100 Meters
Importance:
During mountain travel, patients with chronic obstructive pulmonary disease (COPD) are at risk of experiencing severe hypoxemia, in particular, during sleep.
Objective:
To evaluate whether preventive dexamethasone treatment improves nocturnal oxygenation in lowlanders with COPD at 3100 m.
Design, Setting, and Participants:
A randomized, placebo-controlled, double-blind, parallel trial was performed from May 1 to August 31, 2015, in 118 patients with COPD (forced expiratory volume in the first second of expiration [FEV1] >50% predicted, pulse oximetry at 760 m ≥92%) who were living at altitudes below 800 m. The study was conducted at a university hospital (760 m) and high-altitude clinic (3100 m) in Tuja-Ashu, Kyrgyz Republic. Patients underwent baseline evaluation at 760 m, were taken by bus to the clinic at 3100 m, and remained at the clinic for 2 days and nights. Participants were randomized 1:1 to receive either dexamethasone, 4 mg, orally twice daily or placebo starting 24 hours before ascent and while staying at 3100 m. Data analysis was performed from September 1, 2015, to December 31, 2016.
Interventions:
Dexamethasone, 4 mg, orally twice daily (dexamethasone total daily dose, 8 mg) or placebo starting 24 hours before ascent and while staying at 3100 m.
Main Outcomes and Measures:
Difference in altitude-induced change in nocturnal mean oxygen saturation measured by pulse oximetry (Spo2) during night 1 at 3100 m between patients receiving dexamethasone and those receiving placebo was the primary outcome and was analyzed according to the intention-to-treat principle. Other outcomes were apnea/hypopnea index (AHI) (mean number of apneas/hypopneas per hour of time in bed), subjective sleep quality measured by a visual analog scale (range, 0 [extremely bad] to 100 [excellent]), and clinical evaluations.
Results:
Among the 118 patients included, 18 (15.3%) were women; the median (interquartile range [IQR]) age was 58 (52-63) years; and FEV1 was 91% predicted (IQR, 73%-103%). In 58 patients receiving placebo, median nocturnal Spo2 at 760 m was 92% (IQR, 91%-93%) and AHI was 20.5 events/h (IQR, 12.3-48.1); during night 1 at 3100 m, Spo2 was 84% (IQR, 83%-85%) and AHI was 39.4 events/h (IQR, 19.3-66.2) (P < .001 both comparisons vs 760 m). In 60 patients receiving dexamethasone, Spo2 at 760 m was 92% (IQR, 91%-93%) and AHI was 25.9 events/h (IQR, 16.3-37.1); during night 1 at 3100 m, Spo2 was 86% (IQR, 84%-88%) (P < .001 vs 760 m) and AHI was 24.7 events/h (IQR, 13.2-33.7) (P = .99 vs 760 m). Altitude-induced decreases in Spo2 during night 1 were mitigated by dexamethasone vs placebo by a mean of 3% (95% CI, 2%-3%), and increases in AHI were reduced by 18.7 events/h (95% CI, 12.0-25.3). Similar effects were observed during night 2. Subjective sleep quality was improved with dexamethasone during night 2 by 12% (95% CI, 0%-23%). Sixteen (27.6%) patients using dexamethasone had asymptomatic hyperglycemia.
Conclusions and Relevance:
In lowlanders in Central Asia with COPD traveling to a high altitude, preventive dexamethasone treatment improved nocturnal oxygen saturation, sleep apnea, and subjective sleep quality
Clinical Characteristics, Treatment Patterns and Economic Burden of COPD in Kyrgyzstan:A FRESH AIR Study
Background: COPD prevalence and mortality in Kyrgyzstan are high. Data on clinical and economic impact of COPD in Kyrgyzstan are scarce. This study was part of the FRESH AIR research project that focused on prevention, diagnosis and treatment of chronic lung diseases in low-resource settings.Aim: We aimed to evaluate the clinical characteristics, treatment patterns and economic burden of COPD in Kyrgyzstan.Methods: A representative sample of patients with a spirometry-confirmed diagnosis of COPD was included. All patients were registered in one of the five major hospitals in Kyrgyzstan. Patients were surveyed on COPD risk factors, health-care utilization and patient reported outcomes (CCQ, MRC). Associations with high symptom burden (MRC score >= 4) and cost were assessed using logistic regression analyses.Results: A total of 306 patients were included with mean age 62.1 (SD: 11.2), 61.4% being male, mean BMI 26.9 (SD: 5.2) and mean monthly income 107) and co-payments (331. We found that only GOLD IV and hypertension were significantly associated with high symptom burden. Exacerbations and hypertension were significantly associated with high cost.Conclusion: The clinical and economic burden of COPD on patients and the government in Kyrgyzstan is considerable. Notably, almost half of interviewed patients were current or exsmokers and biomass exposure was high.Public Health and primary carePrevention, Population and Disease management (PrePoD
Asthma rehabilitation at high vs. low altitude and its impact on exhaled nitric oxide and sensitization patterns: Randomized parallel-group trial
Postural Control in Lowlanders With COPD Traveling to 3100 m: Data From a Randomized Trial Evaluating the Effect of Preventive Dexamethasone Treatment
Objective: To evaluate the effects of acute exposure to high altitude and preventive dexamethasone treatment on postural control in patients with chronic obstructive pulmonary disease (COPD). Methods: In this randomized, double-blind parallel-group trial, 104 lowlanders with COPD GOLD 1-2 age 20-75 y, living near Bishkek (760 m), were randomized to receive either dexamethasone (2x4 mg/d p.o.) or placebo on the day before ascent and during a 2-day sojourn at Tuja-Ashu high altitude clinic (3100 m), Kyrgyzstan. Postural control was assessed with a Wii Balance BoardTM at 760 m and one day after arrival at 3100 m. Patients were instructed to stand immobile on both legs with eyes open during five tests of 30 s each, while the center of pressure path length (PL) was measured. Results: With ascent from 760 to 3100 m the PL increased in the placebo group from median (quartiles) 29.2 (25.8 ; 38.2) to 31.5 (27.3 ; 39.3) cm (P< 0.05); in the dexamethasone group the corresponding increase from 28.8 (22.8 ; 34.5) to 29.9 (25.2 ; 37.0) cm was not significant (P=0.10). The mean difference (95% CI) between dexamethasone and placebo groups in altitude-induced changes (treatment effect) was -0.3 (-3.2 to 2.5) cm, (P=0.41). Multivariable regression analysis confirmed a significant increase in PL with higher altitude (coefficient 1.6, 95% CI 0.2 to 3.1, P=0.031) but no effect of dexamethasone was shown (coefficient -0.2, 95% CI -4.0 to 3.6, P=0.925), even when controlled for several potential confounders. PL changes were related more to antero-posterior than lateral sway. 22 of 104 patients had an altitude-related increase in the antero-posterior sway velocity of >25%, what has been associated with an increased risk of falls in previous studies. Conclusions: Lowlanders with COPD travelling from 760 to 3100 m revealed postural instability 24 h after arriving at high altitude, and this was not prevented by dexamethasone
Efficacy of Dexamethasone in Preventing Acute Mountain Sickness in COPD Patients: Randomized Trial
BACKGROUND Patients with COPD may experience acute mountain sickness (AMS) and other altitude-related adverse health effects (ARAHE) when traveling to high altitudes. This study evaluated whether dexamethasone, a drug used for the prevention of AMS in healthy individuals, would prevent AMS/ARAHE in patients with COPD.
METHODS This placebo-controlled, double-blind, parallel-design trial included patients with COPD and Global Initiative for Obstructive Lung Disease grade 1 to 2 who were living below 800 m. Patients were randomized to receive dexamethasone (8 mg/d) or placebo starting on the day before ascent and while staying in a high-altitude clinic at 3,100 m for 2 days. The primary outcome assessed during the altitude sojourn was the combined incidence of AMS/ARAHE, defined as an Environmental Symptoms Questionnaire cerebral score evaluating AMS ≥ 0.7 or ARAHE requiring descent or an intervention.
RESULTS In 60 patients randomized to receive dexamethasone (median [quartiles] age: 57 years [50; 60], FEV 86% predicted [70; 104]; PaO at 760 m: 9.6 kPa [9.2; 10.0]), the incidence of AMS/ARAHE was 22% (13 of 60). In 58 patients randomized to receive placebo (age: 60 y [53; 64]; FEV 94% predicted [76; 103]; PaO: 10.0 kPa [9.1; 10.5]), the incidence of AMS/ARAHE was 24% (14 of 58) (χ statistic vs dexamethasone, P = .749). Dexamethasone mitigated the altitude-induced PaO reduction compared with placebo (mean between-group difference [95% CI], 0.4 kPa [0.0-0.8]; P = .028).
CONCLUSIONS In lowlanders with mild to moderate COPD, the incidence of AMS/ARAHE at 3,100Â m was moderate and not reduced by dexamethasone treatment. Based on these findings, dexamethasone cannot be recommended for the prevention of AMS/ARAHE in patients with COPD undertaking high-altitude travel, although the drug mitigated the altitude-induced hypoxemia
Table_1_Postural Control in Lowlanders With COPD Traveling to 3100 m: Data From a Randomized Trial Evaluating the Effect of Preventive Dexamethasone Treatment.docx
<p>Objective: To evaluate the effects of acute exposure to high altitude and preventive dexamethasone treatment on postural control in patients with chronic obstructive pulmonary disease (COPD).</p><p>Methods: In this randomized, double-blind parallel-group trial, 104 lowlanders with COPD GOLD 1-2 age 20–75 years, living near Bishkek (760 m), were randomized to receive either dexamethasone (2 × 4 mg/day p.o.) or placebo on the day before ascent and during a 2-day sojourn at Tuja-Ashu high altitude clinic (3100 m), Kyrgyzstan. Postural control was assessed with a Wii Balance Board<sup>TM</sup> at 760 m and 1 day after arrival at 3100 m. Patients were instructed to stand immobile on both legs with eyes open during five tests of 30 s each, while the center of pressure path length (PL) was measured.</p><p>Results: With ascent from 760 to 3100 m the PL increased in the placebo group from median (quartiles) 29.2 (25.8; 38.2) to 31.5 (27.3; 39.3) cm (P < 0.05); in the dexamethasone group the corresponding increase from 28.8 (22.8; 34.5) to 29.9 (25.2; 37.0) cm was not significant (P = 0.10). The mean difference (95% CI) between dexamethasone and placebo groups in altitude-induced changes (treatment effect) was -0.3 (-3.2 to 2.5) cm, (P = 0.41). Multivariable regression analysis confirmed a significant increase in PL with higher altitude (coefficient 1.6, 95% CI 0.2 to 3.1, P = 0.031) but no effect of dexamethasone was shown (coefficient -0.2, 95% CI -0.4 to 3.6, P = 0.925), even when controlled for several potential confounders. PL changes were related more to antero-posterior than lateral sway. Twenty-two of 104 patients had an altitude-related increase in the antero-posterior sway velocity of >25%, what has been associated with an increased risk of falls in previous studies.</p><p>Conclusion: Lowlanders with COPD travelling from 760 to 3100 m revealed postural instability 24 h after arriving at high altitude, and this was not prevented by dexamethasone.</p><p>Trial Registration:clinicaltrials.gov Identifier: NCT02450968.</p