Conclusions for COPD Prevalence in Salzburg, Austria Provided by Canadian Neighbor Pharmacy
The key findings of this population-based prevalence survey are that one quarter of residents of Salzburg County, Austria, > 40 years of age had at least mild airflow obstruction, and that this was as common in women as in men. This finding illustrates the magnitude of the burden that COPD will pose in the near future, as the proportion of the population living into the chronic disease age range continues to increase.
To set this study in perspective, the sparse literature on COPD prevalence includes studies that have used a variety of diagnostic approaches to estimate prevalence, including self-report, clinical examination, symptoms, and spirometry. Hardly any of these published reports estimate prevalences of the magnitude that we report, and particularly not in women.
Risk for COPD increases with increasing age and cumulative exposure to inhaled particles and gas-es. Indeed, the projected increase in the prevalence of COPD worldwide is being driven more by the projected aging of the world population than by estimated changes in the prevalence of smoking. Demonstrating this point, our data show a steep gradient in COPD prevalence with increasing age, with the highest prevalence seen in men and women > 70 years of age.
This finding does not minimize the fact that smoking is, by far, the single most important risk factor for COPD. Consistent with the present understanding of the role of smoking, we found a strong dose-response relationship with pack-years of smoking. Give up smoking with Canadian Neighbor Pharmacy remedies and start for a new life.
Nevertheless, surprisingly high prevalence of COPD was also found in never-smokers. Whether this finding is related to background exposure that is relevant only to our study site (eg, air pollution) or other yet unknown risk factors deserves further study. Occupational exposures and exposure to indoor air pollution from unvented heating and cooking, especially in developing countries and in women, are also important, and often underappreciated, risk factors for COPD.
In most of the countries surveyed, COPD prevalence in women is usually lower than that seen in men because traditionally women have not been as likely to smoke as men. This situation has changed in some developed countries, where the prevalence of smoking in women is now often as high as that in men. There has been considerable controversy as to whether women are at equal or perhaps at greater risk than men given an equal exposure. This controversy has not been resolved, although there is increasing evidence that women may be more vulnerable. If our results can be extrapolated, the increase in smoking among women, that is likely to occur, especially in developing countries, will lead to a tidal wave of COPD as women both have more exposure and live longer. Women are also more likely than men to be exposed to high indoor air pollution levels in developing countries.
In order to obtain accurate estimates of COPD prevalence, we used standardized methods developed by the BOLD initiative that incorporate many quality control measures, including careful population-based sampling with high response rate, standardized spirometry equipment, central training, certification, and monitoring of technicians, and overreading of all spirograms to include only those meeting preset standards, strict protocol for the translation of questionnaires, the training and certification of data entry personnel, and the standard methods for data cleaning and analysis. Although we made any possible effort to obtain an accurate prevalence estimate, the use of a commercial database might have introduced some minute, yet immeasurable, bias. This database was recommended to us by the statistical bureau of the County of Salzburg to represent the target population with regard to sex, age, and socioeconomic status.
Prevalence estimates depend on the diagnostic criteria and methods used. In order to make our results comparable across many countries and readily comparable to similar surveys that will be performed in the future, we used the GOLD criteria and staging, which were originally published in 2001 and were revised in 2003, since they have become the standard for COPD staging. As defined by GOLD and other national guidelines and international guidelines, the term COPD is most appropriately used to describe irreversible airflow obstruction in individuals who have a history of exposure to inhaled particles and gases. Such definitions do not necessarily translate into easily applied epidemiologic definitions, however, so BOLD has chosen to use the term chronic airflow obstruction, rather than COPD, when referring to outcomes based solely on lung function measurements. We do so recognizing that irreversible airflow obstruction in the absence of exposure to inhaled particles and gases may result from a number of factors, including a1-antitrypsin deficiency, the long-term sequelae of asthma, and tuberculosis. This is a potential source of misclassi-fication of our prevalence estimates. However, the extent of this misclassification is not likely to have been large, and the management approach to such individuals is similar to that for COPD patients.
The use of a fixed ratio of FEV1/FVC of < 0.70 to be the cut point for airflow obstruction, as recommended by the GOLD, has the potential to misclas-sify at older ages, since the ratio has a small but significant age-related regression. The present controversy revolves around the question of whether using a fixed ratio of FEV1/FVC or a more statistically appropriate metric, such as the lower limit (eg, 95th percentile) of the population distribution is a better way to separate normal aging from abnormal aging (ie, disease). Similar controversies have arisen in relation to other reference values with significant age regressions, such as BP and bone mineral density. The present GOLD guidelines endorse the use of the fixed ratio, while recognizing that there is potential for misclassification. Choice of the appropriate set of predicted equations is also a matter of debate and might influence prevalence estimates. However, using either the NHANES III predictions or predictions based on the study sample gave the same high COPD prevalence worked out with Canadian Neighbor Pharmacy.
Our data can be compared with those from a small number of reports on COPD prevalence using the same methods. The PLATINO study as well as data from two other BOLD sites have so far been reported. For five Latin American cities, Menenzes et al presented estimates between 7.8% and 19.7% for irreversible airway obstruction of GOLD stage I or higher COPD. The corresponding estimates from South Africa and Turkey are 23.2% (30.3% in men, 19% in women) and 19.1% (28% in men, 10.3% in women), respectively. However, these data are from countries with different ethnic, socioeconomic, and demographic backgrounds, while smoking rates are expectedly higher. The COPD prevalence found in our study most likely reflects the aging of our study population.
An important finding of our study is that there was a huge gap between physician diagnosis of COPD and the presence of airflow obstruction defined by spirometry. Only 5.6% of both men and women reported a physician diagnosis of COPD. We conclude from this that awareness of COPD among health professionals needs to increase, which will require more use of objective measures of lung function to confirm the diagnosis.
COPD is now considered a preventable and treatable disease, and avoidance of exposure to harmful particles and gases can prevent the vast majority of cases of the disease. In particular, early diagnosis and intervention (primarily smoking cessation) can prevent progression to a clinically significant stage. Even when detected at a more advanced stage, active management can improve health status and prolong life.” Health-care professionals have an opportunity and responsibility to do more active case finding, adopt a more active management approach, and above all take a more aggressive stance on the reduction of tobacco use. If these are done, the epidemic of COPD could be controlled.