The aim of the Task Force was to derive continuous prediction equations and their lower limits of normal for spirometric indices, which are applicable globally. Over 160,000 data points from 72 ...centres in 33 countries were shared with the European Respiratory Society Global Lung Function Initiative. Eliminating data that could not be used (mostly missing ethnic group, some outliers) left 97,759 records of healthy nonsmokers (55.3% females) aged 2.5-95 yrs. Lung function data were collated and prediction equations derived using the LMS method, which allows simultaneous modelling of the mean (mu), the coefficient of variation (sigma) and skewness (lambda) of a distribution family. After discarding 23,572 records, mostly because they could not be combined with other ethnic or geographic groups, reference equations were derived for healthy individuals aged 3-95 yrs for Caucasians (n=57,395), African-Americans (n=3,545), and North (n=4,992) and South East Asians (n=8,255). Forced expiratory value in 1 s (FEV(1)) and forced vital capacity (FVC) between ethnic groups differed proportionally from that in Caucasians, such that FEV(1)/FVC remained virtually independent of ethnic group. For individuals not represented by these four groups, or of mixed ethnic origins, a composite equation taken as the average of the above equations is provided to facilitate interpretation until a more appropriate solution is developed. Spirometric prediction equations for the 3-95-age range are now available that include appropriate age-dependent lower limits of normal. They can be applied globally to different ethnic groups. Additional data from the Indian subcontinent and Arabic, Polynesian and Latin American countries, as well as Africa will further improve these equations in the future.
The American Thoracic Society has issued guidelines for the 6-minute walk test (6MWT). The 6MWT is safer, easier to administer, better tolerated, and better reflects activities of daily living than ...other walk tests (such as the shuttle walk test). The primary measurement is 6-min walk distance (6MWD), but during the 6MWT data can also be collected about the patient's blood oxygen saturation and perception of dyspnea during exertion. When conducting the 6MWT do not walk with the patient and do not assist the patient in carrying or pulling his or her supplemental oxygen. The patient should walk alone, not with other patients. Do not use a treadmill on which the patient adjusts the speed and/or the slope. Do not use an oval or circular track. Use standardized phrases while speaking to the patient, because your encouragement and enthusiasm can make a difference of up to 30% in the 6MWD. Count the laps with a lap counter. If the 6MWD is low, thoroughly search for the cause(s) of the impairment. Better 6MWD reference equations will be published in the future, so be sure you are using the best available reference equations.
Background Differences in COPD classification have been shown in population data sets when using fifth percentiles as the lower limit of normal (LLN) vs the current GOLD (Global Initiative for ...Chronic Obstructive Lung Disease) guidelines of FEV1 /FVC < 0.70 for detecting airway obstruction and an FEV1 of 80% predicted for detecting and classifying the severity of COPD (GOLD/PP). Many lung function laboratories use 80% predicted to determine whether results are abnormal. Misclassification of the full range of lung diseases in large patient groups when using GOLD/PP criteria instead of the LLN has not been explored previously. Methods We determined the discrepancy rates in pulmonary function test interpretation between the GOLD/PP and LLN methods on prebronchodilator lung function results from a large number of adult patients from the United Kingdom, New Zealand, and the United States. Results In 11,413 patients, the GOLD/PP method misclassified 24%. Ten percent of patients who had normal lung function were falsely classified with a disease category, and 7% of patients were falsely attributed with emphysema. The GOLD/PP method gave false-positive classifications for airflow obstruction and restrictive defects to significantly more men ( P < .01) and older patients ( P < .0001) and also missed airflow obstruction and restrictive defects in younger patients ( P < .0001). Conclusions Using lung function tests on their own with 80% predicted and fixed cut points to determine whether a test is abnormal could misdiagnose > 20% of patients referred for pulmonary function tests. The GOLD/PP method introduces clinically important biases in assessing disease status that could affect allocation to treatment groups. This misclassification is avoided by using the LLN based on the fifth-percentile values.
M. Waatevik and co-investigators from Bergen, Norway, have added to the evidence that smokers with airflow limitation who have oxygen desaturation during a 6-min walk test (6MWT) are: 50% more likely ...to have respiratory exacerbations; more rapidly lose lung function; and have twice the mortality rate when compared with patients who do not desaturate 1. Uniquely, they also found that "desaturators" were much more likely to become cachectic (lose fat-free body mass) during follow-up.
Frailty and Respiratory Impairment in Older Persons Vaz Fragoso, Carlos A., MD; Enright, Paul L., MD; McAvay, Gail, PhD ...
The American journal of medicine,
2012, 2012-Jan, 2012-01-00, 20120101, Letnik:
125, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Abstract Background Among older persons, the association between frailty and spirometry-confirmed respiratory impairment has not been evaluated yet. Methods By using data on white participants aged ...65 to 80 years (Cardiovascular Health Study, N = 3578), we evaluated cross-sectional and longitudinal associations between frailty and respiratory impairment, including their combined effect on mortality. Baseline assessments included frailty status (Fried phenotype: non-frail, pre-frail, and frail) and spirometry. Outcomes included development of frailty features (pre-frail or frail) at year 3 and respiratory impairment (airflow limitation or restrictive pattern) at year 4, and death (median follow-up, 13.2 years). Results At baseline, 48.3% of participants were pre-frail, 5.8% of participants were frail, 13.8% of participants had airflow limitation, and 9.3% of participants had restrictive pattern; 46.1% of participants subsequently died. At baseline, pre-frail and frail were cross-sectionally associated with airflow limitation (adjusted odds ratio OR, 1.62; 95% confidence interval CI, 1.29-2.04 and adjusted OR 1.88; 95% CI, 1.15-3.09) and restrictive pattern (adjusted OR, 1.80; 95% CI, 1.37-2.36 and adjusted OR, 3.05; 95% CI, 1.91-4.88), respectively. Longitudinally, participants with baseline frailty features had an increased likelihood of developing respiratory impairment (adjusted OR, 1.42; 95% CI, 1.11-1.82). Conversely, participants with baseline respiratory impairment had an increased likelihood of developing frailty features (adjusted OR, 1.58; 95% CI, 1.17-2.13). Mortality was highest among participants who were frail and had respiratory impairment (adjusted hazard ratio, 3.91; 95% CI, 2.93-5.22), compared with those who were non-frail and had no respiratory impairment. Conclusion Frailty and respiratory impairment are strongly associated with one another and substantially increase the risk of death when both are present. Establishing these associations may inform interventions designed to reverse or prevent the progression of either condition and to reduce adverse outcomes.
Objective To systematically review the risk of mortality associated with long term use of tiotropium delivered using a mist inhaler for symptomatic improvement in chronic obstructive pulmonary ...disease.Data sources Medline, Embase, the pharmaceutical company clinical trials register, the US Food and Drug Administration website, and ClinicalTrials.gov for randomised controlled trials from inception to July 2010.Study selection Trials were selected for inclusion if they were parallel group randomised controlled trials of tiotropium solution using a mist inhaler (Respimat Soft Mist Inhaler, Boehringer Ingelheim) versus placebo for chronic obstructive pulmonary disease; the treatment duration was more than 30 days, and they reported data on mortality. Relative risks of all cause mortality were estimated using a fixed effect meta-analysis, and heterogeneity was assessed with the I2 statistic.Results Five randomised controlled trials were eligible for inclusion. Tiotropium mist inhaler was associated with a significantly increased risk of mortality (90/3686 v 47/2836; relative risk 1.52, 95% confidence interval, 1.06 to 2.16; P=0.02; I2=0%). Both 10 µg (2.15, 1.03 to 4.51; P=0.04; I2=9%) and 5 µg (1.46, 1.01 to 2.10; P=0.04; I2=0%) doses of tiotropium mist inhaler were associated with an increased risk of mortality. The overall estimates were not substantially changed by sensitivity analysis of the fixed effect analysis of the five trials combined using the random effects model (1.45, 1.02 to 2.07; P=0.04), limiting the analysis to three trials of one year’s duration each (1.50, 1.05 to 2.15), or the inclusion of additional data on tiotropium mist inhaler from another investigational drug programme (1.42, 1.01 to 2.00). The number needed to treat for a year with the 5 µg dose to see one additional death was estimated to be 124 (95% confidence interval 52 to 5682) based on the average control event rate from the long term trials.Conclusions This meta-analysis explains safety concerns by regulatory agencies and indicates a 52% increased risk of mortality associated with tiotropium mist inhaler in patients with chronic obstructive pulmonary disease.
In a population-based study, emphysema was quantified by computed tomography, pulmonary function was assessed by spirometry, and cardiac volumes and function were measured by magnetic resonance ...imaging. Both percent emphysema and the severity of airflow obstruction were linearly related to reductions in left ventricular end-diastolic volume, stroke volume, and cardiac output. These effects were more pronounced among smokers.
In a population-based study, emphysema and the severity of airflow obstruction were linearly related to reductions in left ventricular end-diastolic volume, stroke volume, and cardiac output.
Chronic obstructive pulmonary disease (COPD), defined as airflow obstruction that is not fully reversible,
1
is currently the fourth leading cause of death in the United States.
2
COPD overlaps partially with emphysema, which is characterized by the destruction of alveolar walls and the permanent enlargement of air spaces distal to the terminal bronchioles.
1
,
3
Cor pulmonale, which can occur in very severe COPD, is characterized by elevated pulmonary vascular resistance and right heart failure, with associated reductions in left ventricular filling, left ventricular stroke volume, and cardiac output, although left ventricular ejection fraction is generally preserved.
4
–
7
This disorder may occur . . .
Abstract Measurement of diffusing capacity of the lungs for carbon monoxide (DLCO), also known as transfer factor, is the second most important pulmonary function test (PFT), after spirometry. ...Previously available only in hospital-based PFT labs, DLCO testing is now available at outpatient clinics using a portable device. Compared to spirometry tests, assessments with these devices require very little effort. The patient breathes quietly, inhales the test gas, holds the breath for ten seconds, and then exhales. In adult smokers with post-bronchodilator airway obstruction, a low DLCO greatly increases the probability of the emphysema phenotype of COPD due to cigarette smoking, while a normal DLCO makes chronic asthma more likely. In patients with spirometric restriction (a low FVC with a normal FEV1/FVC), a low DLCO increases the pre-test probability of an interstitial lung disease (ILD), while a normal DLCO makes a chest wall type of restriction more likely. A normal TLC (VA from the single-breath helium dilution provided by a DLCO test) rules out restriction of lung volumes without the need for a body box measurement. In patients with dyspnea of unknown cause, the pattern of a low DLCO with normal spirometry increases the likelihood of pulmonary vascular disease, but this pattern also occurs with several other diseases such as a mild ILD. Once a diagnosis is made, the percent predicted DLCO provides an objective index of disease severity and prognosis. A DLCO below 40% predicted, or a decline in DLCO of more than 4 units, is associated with increased morbidity and mortality.
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