Evaluation of ventilatory function of the small airways]

The results of functional tests and the values of flow-volume and spirometric parameters were reevaluated in 1174 randomly selected patients with no evidence of heart disease. There were 533 patients with normal ventilation and 327 patients with no restrictive disorders. In the latter group 11% of the patients had normal FEV1 and lowered FEF50 and FEF75 values. In those patients obstructive changes would not have been found if expiratory flow rates had not been taken into account as one of the criteria for evaluating airway obstruction. In further 13% of the patients a mild airway obstruction would have been found had only FEV1 been evaluated without taking account of expiratory flow rates. It is concluded that expiratory flow rates along with anamnestic data and clinical status are important indicators of obstructive changes of ventilation, especially as they serve to identify functional disorders while these are still reversible and therapy can be useful.     

Prevalence of airflow limitation on medical check-up in Japanese subjects

The prevalence and mortality of chronic obstructive pulmonary disease (COPD) is expected to increase in the future throughout the world. Little data is available on the prevalence of airflow limitation in Japan, especially on medical check-up. The purpose of this study was to assess the prevalence of airflow limitation in Japanese subjects during medical check-ups. The study subjects were 13,534 Japanese subjects (8,583 males and 4,951 females) aged 40-69 years who underwent medical check-ups at the Japanese Red Cross Kumamoto Health Care Center. Pulmonary function data were analyzed according to smoking habits in each age group. The spirometric criteria for diagnosis of airflow limitation were forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) < 70%. The severity of COPD was defined according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines. People with a medical diagnosis of asthma or individuals who had other pulmonary diseases were excluded from a diagnosis of COPD. The prevalence of airflow limitation was 7.0% in all subjects, 9.1% in males and 3.3% in females. Using the GOLD system, the prevalence of mild, moderate, severe and very severe airflow limitation was 7.06, 1.92, 0.10 and 0.00%, respectively, in males. In females, the prevalence of mild, moderate, severe and very severe airflow limitation was 2.67, 0.63, 0.02 and 0.00%, respectively. Only 10 cases with airflow limitation reported a previous diagnosis of COPD. These results suggest that screening spirometry during medical check-ups can identify many COPD patients not aware of this disease and highlight the need for enhanced screening efforts, intervention and treatment.     

慢性阻塞性肺疾病患者呼出气冷凝液中髓过氧化物酶检测的临床意义

目的探讨慢性阻塞性肺疾病(COPD)患者呼出气冷凝液(EBC)中髓过氧化物酶(MPO)的浓度改变及临床意义。方法收集49例COPD患者、18例健康体检者的EBC,用酶免疫法测定EBC中MPO浓度。结果 COPD组MPO浓度显著高于对照组(P<0.05);COPD组EBC中MPO浓度与患者FEV1占预计值%、PEF呈正相关(均P<0.05)。结论 COPD患者EBC中的MPO浓度能反映炎症和氧化应激程度,监测EBC中的MPO浓度可作为一种较好的评价COPD病情的生物学指标。     

Organic dust disease of airways

Summary Exposure to aerosols of organic dusts such as coffee, tea, spices, soy, fur, and animal food in an occupational setting can affect the respiratory health of industrial workers. Based on our experience with workers from many small industries processing organic materials, we discuss the clinical features and possible mechanisms responsible for the respiratory impairment associated with these types of dust exposure. Significantly higher prevalences for most chronic respiratory symptoms were found among exposed workers than among control workers. Smoking appears to aggravate these symptoms. A large number of exposed workers complained of acute symptoms which developed during the work shift. In exposed workers, significant across-shift reductions in lung function were recorded for all spirometric tests, but particularly for the flow rates at 50% and 25% of vital capacity on maximum expiratory flow-volume curves. Comparison of preshift measured ventilatory capacity tests with predicted normal values indicates that these workers demonstrate obstructive changes affecting primarily flow rate at low lung volumes. The data suggest that exposure to organic aerosols in industrial settings, particularly in conjunction with smoking, may be associated with the development of chronic obstructive lung disease.     

Effects of tiotropium or combined therapy with salmeterol on hyperinflation in COPD

BACKGROUND: Hyperinflation is widely accepted as an abnormal state affecting clinical symptoms, activities of daily living and exercise tolerance in chronic obstructive pulmonary disease (COPD). Reducing hyperinflation is an essential theme in COPD treatment. In this study, we let patients with COPD hyperventilate to evoke hyperinflation, and evaluated the effects of tiotropium alone or in combination with salmeterol on hyperventilation-evoked hyperinflation. METHODS: Thirty-eight patients with COPD received pulmonary function tests including hyperventilation-evoked hyperinflation testing and the St. George's Respiratory Questionnaire (SGRQ) before treatment, after tiotropium administration for 8 weeks, and after combined therapy with salmeterol for 8 weeks. RESULTS: Before treatment, inspiratory capacity (IC) after hyperventilation decreased significantly in a breathing frequency-dependent manner. After tiotropium administration, forced expiratory volume in one second (FEV1) increased significantly. IC after hyperventilation decreased significantly in a breathing frequency-dependent manner; however, IC was significantly greater than that before treatment (at rest, p=0.001; after hyperventilation at twice the resting respiratory rate, p=0.0009; and after hyperventilation at three times the resting respiratory rate, p<0.0001). The SGRQ score also improved significantly. After combined therapy with salmeterol, FEV1 increased significantly compared with after tiotropium alone. However, there was no significant difference between the IC after tiotropium alone and that after combined therapy, at each stage. However, after combined therapy the SGRQ score significantly improved compared with that after tiotropium alone. CONCLUSIONS: Tiotropium improved airflow obstruction and hyperventilation-evoked hyperinflation. In combination with salmeterol, the improvement in airflow obstruction was greater, but hyperventilation-evoked hyperinflation was not further improved.     

咳嗽峰值流速在COPD机械通气患者撤机相关性研究

目的探讨咳嗽峰值流速能否预测COPD机械通气患者成功撤机。方法前瞻性采集19例进行机械通气的重度COPD患者通过自主通气治疗后准备拔除气管捕管前的咳嗽峰值流速，肺功能指标，APACHE Ⅱ，根据最终撤机结果将患者分成两组，采用U检验，Х^2检验，ROC曲线进行分析。结果两组患者CPF有显著性差异（P〈0．05），根据咳嗽峰值流速推测撤机成功所作ROC曲线下面积为0．917（P〈0．05），并确定最佳临界值为29．35L／min，以CPF=29．35 L／min捧测撤机成功率敏感性为66．7％，特异性为100％。结论咳嗽峰值流速在一定程度上可预测机械通气的COPD患者撤机的成功率。     

Characteristics of tidal expiratory flow pattern in healthy people and patient with chronic obstructive pulmonary disease

According to data reported in literature tidal breathing parameters and especially tidal expiratory flow pattern parameters can be useful in distinguishing airflow obstruction. The purpose of the present study was to investigate the parameters of the tidal breathing in healthy people and patients with chronic obstructive pulmonary disease. The study sample included 158 patients with COPD in clinically stable condition and different degree of functional disturbances (FEV1% pred. = 42% +/- 15%; ATS dyspnea scale = 2.5 +/- 0.9; mean +/- SD). The control group of healthy subjects consisted of 43 men and 37 women. The obtained results show that TPTEF/TE (the time necessary to reach the peak expiratory flow in tidal breathing over the total expiratory time) and VPTEF/VE (the volume necessary to reach the peak expiratory flow in tidal breathing over the total expiratory volume) are an independent aspect of tidal breathing. In healthy people these parameters show weak negative correlation with age and high variability. In COPD they are statistically significantly lower than those of healthy people but, since they are highly variable, they cannot be used for an individual assessment. The increase of the mean inspiratory flow (TV/Tin) and the shortening of VPTEF/VE, TPTEF/TE and Tin/Ttot, are indicative of the lung mechanics changes which have a bearing on dyspnea, too. According to factor analysis the parameters of tidal breathing are four separate dimensions: 1. Breathing frequency and respiratory times; 2. Relationship between the respiratory times; 3. Minute ventilation, mean expiratory flow, mean inspiratory flow and tidal volume; 4. Parameters of the expiratory flow VPTEF/VE and TPTEF/TE. The parameters of forced expiration and those of tidal breathing are separate dimensions of the functional profile of patients with COPD.     

Practice guideline 'Medical treatment of COPD'

The practice guideline 'Medical treatment of COPD' completes the practice guideline for diagnostics and non-medicinal treatment. Patients with stable chronic obstructive pulmonary disease (COPD) and minor complaints can be treated with short-acting beta-2-adrenoceptor agonists or anticholinergics or a combination of these. In cases of insufficient clinical control of the condition or if patients use their medication for maintenance, a long-acting bronchodilator is the drug of choice. In patients with severe or very severe COPD (stage III-IV of the criteria of the Global Initiative for Obstructive Lung Disease (GOLD) or with cardiac comorbidity, there is a slight preference for the long-acting anticholinergic tiotropium. Inhaled corticosteroids (ICS) reduce the exacerbation frequency in patients with moderate to severe or very severe COPD (GOLD stage II-IV) and recurrent exacerbations. A combination of ICS with long-acting beta-2-adrenoceptor agonists (LABA) is prescribed in patients with GOLD stage III-IV with at least 2 exacerbations in the past year, a deterioration of the quality of life and with symptoms, if treatment with a LABA alone or an ICS alone results in insufficient improvement. Anticholinergics and beta-2-adrenoceptor agonists have a similar effect on bronchodilation in patients with an acute exacerbation of COPD. If improvement is inadequate, patients with an exacerbation should be treated with prednisolone 30 mg for a period of 7 to 14 days. In outpatients and clinical patients with an exacerbation ofCOPD, an antibiotic is added to prednisolone in very poor lung function (forced expiratory volume in 1 second (FEV1) < 30%) or another risk factor of a severe disease course, such as a respiratory rate > or = 30/min, a systolic blood pressure < 90 mmHg, and disorientation in time, place or person.     

Interpretation of change and longitudinal validity of the quality of life for respiratory illness questionnaire (QoLRIQ) in inpatient pulmonary rehabilitation

The quality of life for respiratory illness questionnaire (QoLRIQ) is an outcome measure for patients with asthma or chronic obstructive pulmonary disease (COPD). This study assessed the longitudinal validity, reliability of the change score and the interpretation of changes on the QoLRIQ in inpatient pulmonary rehabilitation, completed by 108 patients with moderate to severe asthma (39) or COPD (69). Domains and total score of the QoLRIQ changed significant (all p < 0.0002) with standardized response means from 0.46 to 0.90. All QoLRIQ-change scores were significantly correlated with self-rated change in health and in disease symptoms and with change in self-assessed health status (r from 0.2 to 0.61). There were several significant correlations between QoLRIQ-change scores and change in experienced invalidity, emotional well-being, anxiety, depressive symptoms and Rand-36-domains (r from 0.2 to 0.68). The intraclass correlation coefficient of change was 0.90. The size of a minimal important difference (MID), computed from a retrospective global rating of change by the patients and with the standard error of measurement, was 0.5 points on a 7-point response scale. Computation of the MID from retrospective assessment of change may not be valid because this change was significantly correlated to post-treatment health status and significantly higher than serial assessment of change. We conclude that the QoLRIQ is sensitive to change, longitudinally valid and reliable, with a MID of 0.5 points. These results enable the use of the QoLRIQ as an outcome measure in clinical trials with patients with moderate to severe asthma or COPD. The longitudinal measurement properties in less severe patients still need to be studied.     

Associations of depression and anxiety with gender, age, health-related quality of life and symptoms in primary care COPD patients

BACKGROUND: Under-diagnosis of anxiety and depression in Chronic Obstructive Pulmonary Disease (COPD) patients may have a negative impact on patient quality of life and result in disparity between prevalence and the recognition and treatment of these symptoms. OBJECTIVE: To reveal associations of depression and anxiety with demographic, health-related quality of life and clinical characteristics of COPD patients seen in UK primary care. METHODS: Cross-sectional population-based postal survey of COPD patients comprising the EQ-5D visual analogue scale (EQ-5D(VAS)), the COPD symptom control questionnaire, the Hospital Anxiety and Depression Scale, the Medical Research Council dyspnea index. Demographic and spirometric data were collected from general practice records. RESULTS: A total of 170 (57%) patients consented to take part. Data are reported on 110 of these patients for whom up-to-date spirometry was available. Approximately one in five participants reported 'caseness' for depression (20.8%) and one in three reported anxiety (32.7%). Age and high levels of symptoms were independent predictors of anxiety and depression, as was the EQ-5D(VAS) of depression. CONCLUSIONS: These data suggest that in UK primary care, depressive and anxious symptoms in COPD are related to age and high levels of symptoms. Depression is also associated with lower patient-reported generic health status. The data suggest that assessment and treatment for depression and anxiety should be considered for all COPD patients, not just those with more severe clinical levels of disease. The potential of the EQ-5D(VAS) as a screening tool for anxiety and depression in primary care COPD patients also merits study.     

Living with failing lungs: the doctor-patient relationship

OBJECTIVE: The aim of the present study was to explore the perceptions and needs of chronic obstructive pulmonary disease (COPD) patients by a qualitative study using semi-structured interviews. METHODS: Sixteen patients with a diagnosis of COPD (age range 59-75 years) were recruited from two sample frames. One group were under the care of GPs and the second had received in-patient care previously at a district general hospital. Participants had either moderate or severe impairment of respiratory function identified by spirometric testing [forced expiratory volume in 1 second (FEV(1)) <50% of predicted value]. RESULTS: Primary and secondary care samples were chosen in the hope of identifying various aspects of care. However, the patients in this study primarily chose to discuss their relationship with their GP when considering aspects of their lives as a COPD patient. The most significant findings related to the respondents' chronic patient status, their ability to control symptoms and expectations of health care support. All these factors were connected to their perceived relationship with their GP. CONCLUSIONS: Doctors, as gatekeepers of health care resources, were seen to have immense power over the patients' lives. The need to be perceived in a good light by their doctor was intensified by their low self-esteem, poor control of symptoms and their chronic disease status. The majority of patients expressed a need to take a more active part in the decision-making processes involved in the management of their disease. A more balanced doctor-patient relationship could develop if frank and open discussions are based upon a shared decision-making approach.     

Prevalence of chronic obstructive pulmonary disease and associated factors: the PLATINO Study in São Paulo, Brazil

Chronic obstructive pulmonary disease (COPD) is now a major public health concern; deaths attributable to COPD in Latin America have increased by 65.0% in the last decade. This study was aimed at evaluating COPD prevalence and associated factors in adults (> 40 years) living in Greater Metropolitan S?o Paulo, Brazil. The study is part of the Proyecto Latinoamericano de Investigación en Obstrucción Pulmonar (The PLATINO Project), a multi-center survey on COPD burden in Latin America, with S?o Paulo as the first center where the project has been carried out. A population-based sample was selected in multiple stages. Spirometry tests were performed in each subject pre- and post-bronchodilator and COPD was mainly defined as the ratio of forced expiratory volume to forced vital capacity below 70.0% (fixed ratio definition). Other spirometric criteria were also used for the diagnosis of COPD. COPD prevalence was 15.8% (95%CI: 13.5-18.1) using the fixed ratio definition. COPD was positively associated with age and smoking and inversely with body mass index. Utilization of different COPD spirometry criteria resulted in different percentages of COPD, but similar associated factors.     

Influence of noninvasive ventilation by BiPAP on exercise tolerance and respiratory muscle strength in chronic obstructive pulmonary disease patients (COPD)

This study aimed to assess the effect of BiPAP, by nasal mask, on exercise tolerance and respiratory muscle strength in patients with a clinical and spirometric diagnosis of moderate/severe COPD (FEV1 < 60% of predicted). Ten patients of 59.4+/-8.9 years old, with FEV1/FVC <70% of predicted level, were treated with 30 minutes of BiPAP (IPAP:10 and 15 cmH2O; EPAP:4 cmH2O), three days per week, during two months. Before and after the treatment, spirometry, inspiratory (MIP) and expiratory (MEP) muscle strength and the distance walked in six minutes (6MWT) were measured. We observed a significant increase (Wilcoxon, p<0.05) in the mean values of MIP (from -55+/-17 to -77+/-19, respectively), MEP (from 75+/-20 to 109+/-36, respectively) and walking distance (from 349+/-67 to 448+/-75). Based on these results, we concluded that BiPAP improves respiratory muscle strength and exercise tolerance in these COPD patients.     

肺减容术在治疗重度慢性阻塞性肺气肿中的研究进展

重度慢性阻塞性肺病（COPD）是一种常见病,终末期患者最终导致心肺功能衰竭而死亡。肺容积减少术为部分重度慢性阻塞性肺气肿患者提供了一种有效的治疗方法,江门市新会区人民医院开展肺容积减少术治疗重度慢性阻塞性肺气肿已有八年,并取得较好的临床疗效。本文综合国内外关于肺减容术治疗重度慢阻肺方面的文献资料,结合该院临床经验,现就其基础理论与实施方法作一综述。     

沙美特罗替卡松联合白三烯受体拮抗剂治疗对重度COPD患者稳定期IC变化的影响

目的：研究重度慢性阻塞性肺疾病 （Chronic obstructive pulmonary disease,COPD） 患者使用沙美特罗替卡松联合白三烯受体拮抗剂 （Leukotriene receptor antagonists,LTRA） 及单独使用沙美特罗替卡松治疗前后深吸气量的变化。方法：选取 60 例重度 COPD 患者随机分为观察组 （n=30） 及对照组 （n=30）,观察组给予沙美特罗替卡松 （500 μg/50 μg） 早晚各一次吸入联合白三烯受体拮抗剂 （10 mg） 上午口服一次,对照组给予沙美特罗替卡松沙美特罗替卡松 （500μg/50μg） 早晚各一次吸入,两组治疗 6 个月。在治疗前、治疗 3 个月、6 个月后行肺功能检测、IC（inspiratory capacity,IC） 检测 ;同时采用 6 min 步行距离评价运动能力,呼吸困难指数 mmRC 评价生活质量。结果：在治疗 3 个月及 6 个月观察组 IC 优于对照组 （P〈0.05） ;在各治疗阶段呼吸困难指数 mmRC 观察组均优于对照组 （P〈0.05）。结论：沙美特罗替卡松联合白三烯受体拮抗剂治疗重度COPD 较单用沙美特罗替卡松对IC 肺功能和生活质量的改善作用更明显,早期改善 COPD 的运动耐量,延缓肺功能的下降。     

The last breath. The decision to ventilate patients with severe chronic obstructive pulmonary disease or not

Three patients, a 74-year-old man and 2 women aged 40 and 58 years, were admitted to the hospital on a number of occasions due to respiratory insufficiency as a result of progressive debilitating COPD. Weaning from mechanical ventilation became increasingly difficult. Therefore, in two patients it was eventually decided not to apply mechanical ventilation again; they died after the next COPD exacerbation. The 40-year-old woman was eligible for a lung transplant and was placed on the waiting list for this procedure. The decision to mechanically ventilate patients with severe COPD and respiratory insufficiency is fraught with therapeutical, emotional and ethical dilemma. Objective criteria indicating a poor outcome in mechanically ventilated patients with severe COPD are: a forced expiratory volume in one second lower than 700 ml, being housebound, advanced age, cardiac comorbidity, and a low serum albumin concentration prior to mechanical ventilation. Since subjective criteria such as the patient's own wishes should also be considered, a policy is advocated in which the consultant pulmonologist regularly evaluates the available data and communicates the feasibility of mechanical ventilation.     

噻托溴铵联合布地奈德福莫特罗粉吸入剂治疗COPD加重期的临床疗效

目的分析噻托溴铵粉吸入剂联合布地奈德福莫特罗粉吸入剂治疗慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)急性加重期的临床疗效。方法选择我院COPD急性加重期患者共70例,数字表法随机分两组,每组35例,对照组的患者给予布地奈德福莫特罗粉吸入剂治疗,观察组在该基础上增加噻托溴铵粉吸入剂。比较两组住院时间、治疗前后患者肺功能指标、血气分析结果、C反应蛋白、总有效率。结果观察组住院时间短于对照组,肺功能一秒末用力呼气容积、最高呼气流量、第一秒用力呼气容积/肺活量高于对照组,治疗后患者血气分析改善、C反应蛋白低于对照组,总有效率高于对照组,P<0.05。结论布地奈德福莫特罗粉吸入剂联合噻托溴铵粉吸入剂对于COPD急性加重期的治疗效果确切。     

Lower inhaled steroid requirement with a fluticasone/salmeterol combination in family practice patients with asthma or COPD

BACKGROUND: Previous studies on inhaled steroid and long-acting beta2-agonist combination products may not be representative for the asthma and chronic obstructive pulmonary disease (COPD) patients in family practice. OBJECTIVES: To compare in a group of doctor-diagnosed patients with asthma or COPD, the effects of a lower dose of fluticasone in a combination product with salmeterol with conventional treatment (i.e. a higher dose of fluticasone), both supplemented with as-needed use of a short-acting bronchodilator. METHODS: The study was a 12-week multicentre, randomized controlled, double-blind trial. In all, 41 family practices recruited 137 patients diagnosed with asthma and 40 patients diagnosed with COPD. Primary outcome was the forced expiratory volume in 1 second (FEV1) as percentage of predicted. Morning peak expiratory flow (PEF), symptom-free days, health status [Asthma Quality of Life Questionnaire (AQLQ) and St. George's Respiratory Questionnaire (SGRQ)], exacerbations, use of short-acting bronchodilators and adverse events were secondary outcomes. RESULTS: FEV1% predicted increased 2.6% (SD 8.3) in fluticasone/salmeterol- and 0.01% (SD 6.6) in fluticasone-treated patients (overall: P=0.036, asthma: P=0.025 and COPD: P=0.700). PEF increased in favour of fluticasone/salmeterol in asthma patients only (P=0.016). Fluticasone/salmeterol-treated asthma patients had 1.1 more symptom-free days per week (P=0.044); no such effect was observed for COPD (P=0.769). There were no differences in total AQLQ and SGRQ scores, exacerbations, use of reliever puffs or adverse effects. CONCLUSIONS: In family practice patients diagnosed with asthma, several treatment goals were better achieved with a lower dose of fluticasone and salmeterol in a combination product than with a higher dose of fluticasone. We found no differences between the two approaches for patients with COPD.     

慢性阻塞性肺病患者营养状况与肺通气功能关系的研究

目的探讨慢性阻塞性肺病(chronicobstructivepulmonarydisease,COPD)患者营养状况对肺通气功能的影响。方法对149例COPD患者根据其营养状况分为营养正常组和营养不良组,再进行肺通气功能测定,观察指标包括最大通气量(MVV),用力肺活量(FVC),第一秒用力呼气容积(FEV1),最大呼气流量(PEF),最大呼气中段流量(MMEF)。结果营养不良组与营养正常组比较,MVV、FVC、PEF、FEV1等反映呼吸肌的指标相差非常显著(P<0.001),且两组在COPD病程同一阶段(肺气肿、肺心病)肺通气功能各值比较也显示营养不良组呼吸肌力等指标比正常组降低明显(P<0.05)。结论COPD合并营养不良对与呼吸肌有关的肺通气功能指标有明显影响。     

Annals Journal Club: Clinical Relevance of Fixed Ratio vs Lower Limit of Normal of FEV1/FVC in COPD: Patient-Reported Outcomes From the CanCOLD Cohort

PURPOSEThe way in which spirometry is interpreted can lead to misdiagnosis of chronic obstructive pulmonary disease (COPD) resulting in inappropriate treatment. We compared the clinical relevance of 2 criteria for defining a low ratio of forced expiratory volume in 1 second to forced vital capacity (FEV₁/FVC): the fixed ratio and the lower limit of normal.METHODSWe analyzed data from the cross-sectional phase of the population-based Canadian Cohort of Obstructive Lung Disease (CanCOLD) study. We determined associations of the spirometric criteria for airflow limitation with patient-reported adverse outcomes, including respiratory symptoms, disability, health status, exacerbations, and cardiovascular disease. Sensitivity analyses were used to explore the impact of age and severity of airflow limitation on these associations.RESULTSWe analyzed data from 4,882 patients aged 40 years and older. The prevalence of airflow limitation was 17% by fixed ratio and 11% by lower limit of normal. Patients classified as having airflow limitation by fixed ratio only had generally small, nonsignificant increases in the odds of adverse outcomes. Patients having airflow limitation based on both fixed ratio and lower limit of normal had larger, significant increases in odds. But strongest associations were seen for patients who had airflow limitation by both fixed ratio and lower limit of normal and also had a low FEV₁, defined as one less than 80% of the predicted value.CONCLUSIONSOur results suggest that use of the fixed ratio alone may lead to misdiagnosis of COPD. A diagnosis established by both a low FEV₁/FVC (according to fixed ratio and/or lower limit of normal) and a low FEV₁ is strongly associated with clinical outcomes. Guidelines should be reconsidered to require both spirometry abnormalities so as to reduce overdiagnosis of COPD.