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1.
Chronic obstructive pulmonary disease (COPD) is a significant health problem in developed countries. We aimed to estimate the prevalence of COPD in a single Spanish healthcare area. We also aimed to assess if there are any differences in prevalence and spirometry use among primary care services by utilizing already registered information. We designed a cross-sectional study to determine the prevalence of COPD and the performance of spirometries in each primary care service. A total of 8,444 patients were diagnosed with COPD, with a prevalence of 2.6% for individuals older than 39 years. The prevalence increased with age and was much higher in men. Significant heterogeneity was found in the prevalence of COPD and spirometry use among primary care services. COPD was underdiagnosed and there was wide variability in spirometry use in our area. Greater efforts are needed to diagnose COPD in order to improve its clinical outcomes and to refine registries so that they can be used as reliable sources of information  相似文献   
2.
AIMS: The developing world is particularly at risk of an increasing health burden due to an increased prevalence of Chronic Obstructive Pulmonary Disease (COPD) secondary to increasing tobacco consumption. However, research is scarce. The objectives of this study were to assess the current competence for diagnosing COPD in primary care in a resource-limited setting in Brazil, and to develop a local patient profile for case-finding. METHODS: 34 general practitioners (GPs) in five areas of northern Brazil recruited adult patients with principal complaints of cough and/or shortness of breath who then had spirometry (n = 142). RESULTS: For the dichotomous variable 'COPD' the degree of agreement between GP diagnosis (n = 64, 18.3%) and spirometric outcome (n = 36, 25.4%) was poor, with Kappa = 0.055 (SE 0.087) and DOR = 1.35. False-positive and false-negative diagnosis proportions were 19.8% and 75%, respectively. Independent risk factors were 'smoking history of more than five pack years' and 'presence of both dyspnoea and cough'. It requires the testing of 2.2 smokers with more than five pack years to detect one patient at risk. CONCLUSIONS: COPD is a common yet underdiagnosed disease in Brazilian primary care. Spirometry improves diagnostic competence and case-finding substantially. If applied in a pre-selected high-risk population, we believe spirometry can be a cost-effective diagnostic tool for case-finding in the resource-limited setting. This study provides important baseline information for effective guideline implementation.  相似文献   
3.
Summary The objective of this study was to investigate if the dust in a mill producing soft paper tissue caused respiratory symptoms or impaired respiratory function. Using a questionnaire and spirometry, 355 persons were examined. They were divided into three groups according to present exposure to dust; low (< 1 mg/m3), moderate (1–5 mg/m3) and heavy (> 5 mg/m3). There was a dose-dependent increase of symptoms from the upper respiratory tract. However, coughing and coughing with phlegm were not found to be more common among persons with heavy exposure compared to those with low exposure to the dust. There was no difference in FEV, or FVC during a work shift. Persons with long-term (> 10 years) and heavy exposure to dust seemed to have impaired respiratory function compared to those with low and/or short-term exposure to the dust.  相似文献   
4.
In children with acute obstructive lung disease gas exchange is affected by ventilation-perfusion mismatch and the degree of bronchoconstriction. Standard lung function measurements do not reflect the impairment in gas exchange. Alternatively, the effective pulmonary blood flow (EPBF), that is, the proportion of the cardiac output that is supplying well-ventilated lung units, can give accurate and noninvasive estimates of ventilation-perfusion mismatch. We measured EPBF with the argon freon ?22 rebreathing technique in children with acute severe asthma to assess their response to nebulized salbutamol and to determine whether induced changes in the EPBF could be predicted from baseline measurements. Twenty-four children admitted with an acute asthma attack had spirometry and triplicate EPBF measurements before and after nebulized salbutamol. Eighteen patients had repeated tests 50 days later when fully recovered; 4 patients were taking methylxanthines on at least one occasion. The mean forced expiratory volume in 1 sec (FEV1) rose from 55% of predicted to 66% after salbutamol and to 83% with recovery. The mean coefficients of variation for EPBF measurements on the three test occasions were 11.3%, 8.2%, and 9%. Except in children on methylxanthines, the EPBF values were reduced during the acute asthma attack (median, 2.53 L/min/m2; range, 1.99–3.60 L/min/m2) compared with paired values obtained after recovery (median, 2.89 L/min/m2; range, 2.2Eb4.04 L/min/m2) (P = 0.009). Salbutamol caused a highly significant increase in EPBF from 2.88 L/min/m2 (range, 1.86–3.80) before treatment to 3.34 L/min/m2 (range, 2.264.65) immediately afterwards (P = 0.0003). The spirometric indices did not relate to the changes in the EPBF values. However, when the effective stroke volume index was calculated in 11 patients, the changes induced by nebulized salbutamol had a significant inverse relation with the pretreatment FEV, (P = 0.61; P = 0.02). In conclusion, the argon freon-22 rebreathing technique can be used successfully and reproducibly to measure EPBF in children with an acute asthma attack. Except in children taking methylxanthines, EPBF during the acute attack is reduced and rises significantly after salbutamol. EPBF values after recovery were significantly higher than the presalbutamol values during the attack. Spirometric indices do not relate to the EPBF changes but are inversely related to the effective stroke volume changes. Pediatr Pulmonol. 1994; 17:370–377. © 1994 Wiley-Liss, Inc.  相似文献   
5.

Purpose

There is presently an ongoing debate on the relative merits of suggested criteria for spirometric airway obstruction. This study tests the null hypothesis that no superiority exists with the use of fixed ratio (FR) of forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) < 0.7 versus less than lower limit predicted (LLN) criteria with or without FEV1 <80% predicted in regards to future mortality.

Methods

In 1988–1994 the Third National Health and Nutrition Examination Survey (NHANES III) measured FEV1 and FVC with mortality follow-up data through December 31, 2011. For this survival analysis 7472 persons aged 40 and over with complete data formed the analytic sample.

Results

There were a total of 3554 deaths. Weighted Cox proportional hazards regression revealed an increased hazard ratio in persons with both fixed ratio and lower limit of normal with a low FEV1 (1.79, p < 0.0001), in those with fixed ratio only with a low FEV1 (1.77, p < 0.0001), in those with abnormal fixed ratio only with a normal FEV1 (1.28, p < 0.0001) compared with persons with no airflow obstruction (reference group). These remained significant after adjusting for demographic variables and other confounding variables.

Conclusions

The addition of FEV1 < 80% of predicted increased the prognostic power of the fixed ratio <0.7 and/or below the lower limit of predicted criteria for airway obstruction.  相似文献   
6.
7.
目的 了解中国≥40岁居民中COPD高危人群的分布和特征,为COPD综合防控提供依据。方法 对象来源于2014-2015年中国居民COPD监测项目中内地31个省(自治区、直辖市),采用多阶段分层整群随机抽样,共调查125个监测点的≥40岁研究对象75 107名。采用面对面询问调查方式收集相关信息,符合四项条件之一者定义为高危人群:慢性呼吸道症状、危险因素暴露史、慢性呼吸系统疾病史、家族史。对样本进行复杂抽样加权估计高危人群比例以及95% CI结果 74 296名调查对象纳入分析,至少符合一项条件的COPD高危人群比例为89.5%(95% CI:87.8%~91.2%),且随年龄增大比例增加(P<0.001);男性高于女性(P<0.001)、乡村高于城镇(P<0.001);西部农村男性中高危人群比例最高(98.8%,95% CI:98.0%~99.6%)。至少符合两项条件、三项条件和四项条件的高危人群占总人数的比例分别为32.0%(95% CI:29.7%~34.2%)、7.4%(95% CI:6.6%~8.3%)和1.5%(95% CI:1.2%~1.8%)。在高危人群中只有一项危险因素暴露者所占比重最大(61.7%,95% CI:59.8%~63.7%)。结论 中国≥40岁居民中COPD高危人群近九成,应在该人群中开展COPD筛查,采取综合防控策略降低人群危险因素流行水平。  相似文献   
8.
Despite evidence showing an improvement in nutritional outcomes following diagnosis by newborn screening (NBS) for cystic fibrosis (CF), the impact on pulmonary outcomes has been less clear. In this review the approaches to measurement of early lung function and knowledge gained from NBS CF cohorts will be described. Studies which have compared outcomes in those diagnosed by NBS to those diagnosed following symptomatic presentation will be presented. Compiling the evidence base used to evaluate the impact of NBS on pulmonary outcomes has been complicated by improvements in clinical management, infection control practices, as well as public health interventions (such as tobacco smoking bans in public places) that have evolved substantially over recent decades. Forced expiratory volumes have been used as the main outcome but it is important not to draw conclusions for ‘early lung function’ from tests such as spirometry alone, which lack sensitivity in early lung disease. There is, at present, insufficient evidence to draw firm conclusions about the effect of NBS on early lung function. In an era of highly effective treatments targeting the underlying molecular defect responsible for CF, future opportunities for early initiation of treatment may mean that the impact of NBS on early lung function may yet to be realised.  相似文献   
9.
The ALAT and SEPAR Treatment and Control of Smoking Groups have collaborated in the preparation of this document which attempts to answer, by way of PICO methodology, different questions on health interventions for helping COPD patients to stop smoking.The main recommendations are: (i) moderate-quality evidence and strong recommendation for performing spirometry in COPD patients and in smokers with a high risk of developing the disease, as a motivational tool (particularly for showing evidence of lung age), a diagnostic tool, and for active case-finding; (ii) high-quality evidence and strong recommendation for using intensive dedicated behavioral counselling and drug treatment for helping COPD patients to stop smoking; (iii) high-quality evidence and strong recommendation for initiating interventions for helping COPD patients to stop smoking during hospitalization with improvement when the intervention is prolonged after discharge, and (iv) high-quality evidence and strong recommendation for funding treatment of smoking in COPD patients, in view of the impact on health and health economics.  相似文献   
10.
BackgroundPreserved ratio impaired spirometry (PRISm) is a common spirometry finding, but its heterogeneous manifestations and frequent transitions to airflow limitation (AFL), chronic obstructive pulmonary disease, or normal spirometry hinder establishing an appropriate management strategy. This study examined whether transition to AFL and baseline comorbidities are more frequent in subjects with definite PRISm (PRISm confirmed on both current and past two spirometry tests) versus incident PRISm (PRISm confirmed only on a current test with past normal spirometry records) than in normal spirometry.MethodsArchived medical check-up data of subjects aged ≥40 years (n = 10828) with two past spirometry records, in a Japanese hospital, were cross-sectionally analyzed. Among them, data from those with follow-up spirometry after three years (n = 6467) were used to evaluate transition to AFL. PRISm was defined as forced volume in 1 s (FEV1)/forced vital capacity ≥0.7 and % predicted FEV1 < 80%.ResultsOverall PRISm prevalence was 6.5%. In multivariable models adjusted for age, sex, smoking status, and body mass index, definite PRISm (n = 290), but not incident PRISm (n = 183), was associated with elevated hemoglobin A1c and C-reactive protein levels, and higher rates of asthma, hypertension, hyperlipidemia, and diabetes than was consistent normal spirometry (n = 9694). The transition to AFL after three years was more frequent in definite PRISm, but not incident PRISm, than in normal spirometry (adjusted hazard ratio [95% confidence interval] = 6.21 [3.42–10.71] and 1.45 [0.23–4.73], respectively).ConclusionsMultiple confirmed PRISm on past and baseline spirometry is closely associated with metabolic syndrome factors, asthma history, and future AFL development.  相似文献   
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