9 research outputs found
Ethnic differences in respiratory impairment
Objective Spirometric Z scores by lambda-mu-sigma (LMS) rigorously account for age-related changes in lung function. Recently, the Global Lung Function Initiative (GLI) expanded LMS spirometric Z scores to multiple ethnicities. Hence, in aging populations, the GLI provides an opportunity to rigorously evaluate ethnic differences in respiratory impairment, including airflow limitation and restrictive pattern. Methods Using data from the Third National Health and Nutrition Examination Survey, including participants aged 40-80, we evaluated ethnic differences in GLI-defined respiratory impairment, including prevalence and associations with mortality and respiratory symptoms. Results Among 3506 white Americans, 1860 African Americans and 1749 Mexican Americans, the prevalence of airflow limitation was 15.1% (13.9% to 16.4%), 12.4% (10.7% to 14.0%) and 8.2% (6.7% to 9.8%), and restrictive pattern was 5.6% (4.6% to 6.5%), 8.0% 6.9% to 9.0%) and 5.7% (4.5% to 6.9%), respectively. Airflow limitation was associated with mortality in white Americans, African Americans and Mexican Americans - adjusted HR (aHR) 1.66 (1.23 to 2.25), 1.60 (1.09 to 2.36) and 1.80 (1.17 to 2.76), respectively, but associated with respiratory symptoms only in white Americans - adjusted OR (aOR) 2.15 (1.70 to 2.73). Restrictive pattern was associated with mortality but only in white Americans and African Americans - aHR 2.56 (1.84 to 3.55) and 3.23 (2.06 to 5.05), and associated with respiratory symptoms but only in white Americans and Mexican Americans-aOR 2.16 (1.51 to 3.07) and .12 (1.45 to 3.08), respectively. Conclusions In an aging population, we found ethnic differences in GLI-defined respiratory impairment. In particular, African Americans had high rates of respiratory impairment that were associated with mortality but not respiratory symptoms
Use of forced vital capacity and forced expiratory volume in 1 second quality criteria for determining a valid test
The 2005 American Thoracic Society (ATS)/European Respiratory Society (ERS) spirometry
guidelines define valid tests as having three acceptable blows and a repeatable forced vital capacity (FVC)
and forced expiratory volume in 1 s (FEV1). The aim of this study was to determine how reviewer and
computer-determined ATS/ERS quality could affect population reference values for FVC and FEV1.
Spirometry results from 7777 normal subjects aged 8–80 years (NHANES (National Health and
Nutrition Examination Survey) III) were assigned quality grades A to F for FVC and FEV1 by a computer
and one reviewer (reviewer 1). Results from a subgroup of 1466 Caucasian adults (aged 19–80 years) were
reviewed by two additional reviewers. Mean deviations from NHANES III predicted for FVC and FEV1
were examined by quality grade (A to F).
Reviewer 1 rejected (D and F grade) 5.2% of the 7777 test sessions and the computer rejected ∼16%,
primarily due to end-of-test (EOT) failures. Within the subgroup, the computer rejected 11.5% of the
results and the three reviewers rejected 3.7–5.9%. Average FEV1 and FVC were minimally influenced by
grades A to C allocated by reviewer 1.
Quality assessment of individual blows including EOT assessments should primarily be used as an aid
to good quality during testing rather than for subsequently disregarding data. Reconsideration of EOT
criteria and its application, and improved grading standards and training in over-reading are required.
Present EOT criteria results in the exclusion of too many subjects while having minimal impact on
predicted values
Inhaled corticosteroids and growth of airway function in asthmatic children
Airway inflammation and remodelling play an important role in the
pathophysiology of asthma. Remodelling may affect childhood lung function,
and this process may be reversed by anti-inflammatory treatment. The
current study assessed longitudinally whether asthma affects growth of
airway function relative to airspaces, and if so whether this is redressed
by inhaled corticosteroids (ICS). Every 4 months for up to 3 yrs, lung
function was assessed in 54 asthmatic children (initial age 7-16 yrs), who
inhaled 0.2 mg salbutamol t.i.d. and 0.2 mg budesonide t.i.d.
(beta2-agonist (BA)+ICS), or placebo (PL) t.i.d. (BA+PL) in a randomised,
double-blind design. Measurements were carried out before and after
maximal bronchodilation. Airway growth was assessed from the change of
forced expiratory volume in one second and of maximal expiratory flows (at
60% and 40% of total lung capacity (TLC) remaining in the lung) relative
to TLC, as measures of more central, intermediate and more peripheral
airways. Growth patterns were compared with the longitudinal findings in
376 healthy children. Airway patency after maximal bronchodilation in
patients on BA+PL remained reduced compared to healthy subjects, whereas
in patients on BA+ICS a marked improvement was observed to subnormal. No
differences between patients and controls could be demonstrated for growth
patterns of central and intermediate airway function. Compliance with
BA+ICS was 75% of the prescribed dose, resulting in significant, sustained
improvement of symptoms and postbronchodilator calibre of central and
intermediate airways to subnormal within 2 months, but postbronchodilator
small airway patency remained reduced, though improved compared to
patients on BA+PL. Anti-inflammatory treatment of asthmatic children is
associated with normal functional development of central and intermediate
airways. The persistently reduced postbronchodilator patency of peripheral
airways may reflect remodelling, or insufficient anti-inflammatory
treatment
Comparison of pulmonary function in immigrant vs US-born Asian Indians
Objective: This study investigated whether there is a difference in pulmonary function between healthy adult US-born Asian Indians and immigrant Asian Indians attributable to country of birth, environmental, and socioeconomic factors. Design: FEV 1, FVC, and forced mid-expiratory flow between 25% and 75% of vital capacity (FEF25-75) were measured in India-born and US-born subjects residing in the Chicago metropolitan area. Hollingshead Index of Social Position was used to evaluate socioeconomic factors. Results: There were 262 India-born (61.8% male), and 200 US-born (50% male) subjects who were healthy lifelong nonsmokers; their age range was 16 to 36 years. US-born Asian Indian men and women were taller and had higher pulmonary function values for height and age compared with immigrant Asian Indian men and women. The differences were most pronounced in women:about 7% for FVC, 9% for FEV 1, and 17% for FEF25-75. Immigrant and US-born subjects did not differ in socioeconomic position. Conclusion: We conclude that US-born Asian Indian men and women have higher pulmonary function values for age and height compared with immigrant Asian Indian men and women. This probably refl ects the effect of differing environmental conditions, which cause year-of-birth trends in lung volumes