Predictors of lung function and its decline in mild to moderate COPD in association with gender: results from the Euroscop study

Exploring the Prevalence of Respiratory Failure in Adults Presenting With Acute Exacerbations of Chronic Obstructive Pulmonary Disease

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) poses a significant global health burden and is a leading cause of morbidity and mortality. Acute exacerbations of COPD often lead to respiratory failure, necessitating a thorough understanding of its prevalence. This study aimed to investigate the prevalence of respiratory failure among adult patients experiencing acute exacerbations of COPD.

MATERIALS AND METHODS

A descriptive, cross-sectional study was conducted over a span of seven months at the internal medicine department of Hayatabad Medical Complex, Peshawar. A total of 255 adult patients with acute exacerbations of COPD were included, and their demographic data, as well as arterial blood gas (ABG) analysis results, were collected. The prevalence of respiratory failure was defined by specific arterial blood gas criteria.

RESULTS

The study revealed a notable prevalence of respiratory failure (41.18%) among COPD patients presenting with acute exacerbations. Factors such as older age and male gender were identified as being associated with a heightened risk of respiratory failure.

CONCLUSION

In conclusion, acute exacerbations of COPD predominantly affect middle-aged males (65.5%), with the 51-60 age group being the most impacted. Respiratory failure was present in over 41% of cases. ABG analysis indicated significant acid-base imbalances, hypoxemia, and hypercapnia, with compensatory chronic respiratory acidosis. These findings highlight the need for targeted interventions to manage and prevent COPD exacerbations, especially in middle-aged men.

The Molecular Blueprint for Chronic Obstructive Pulmonary Disease (COPD): A New Paradigm for Diagnosis and Therapeutics

The global prevalence of chronic obstructive pulmonary disease (COPD) has increased over the last decade and has emerged as the third leading cause of death worldwide. It is characterized by emphysema with prolonged airflow limitation. COPD patients are more susceptible to COVID-19 and increase the disease severity about four times. The most used drugs to treat it show numerous side effects, including immune suppression and infection. This review discusses a narrative opinion and critical review of COPD. We present different aspects of the disease, from cellular and inflammatory responses to cigarette smoking in COPD and signaling pathways. In addition, we highlighted various risk factors for developing COPD apart from smoking, like occupational exposure, pollutants, genetic factors, gender, etc. After the recent elucidation of the underlying inflammatory signaling pathways in COPD, new molecular targeted drug candidates for COPD are signal-transmitting substances. We further summarize recent developments in biomarker discovery for COPD and its implications for disease diagnosis. In addition, we discuss novel drug targets for COPD that could be explored for drug development and subsequent clinical management of cardiovascular disease and COVID-19, commonly associated with COPD. Our extensive analysis of COPD cause, etiology, diagnosis, and therapeutic will provide a better understanding of the disease and the development of effective therapeutic options. In-depth knowledge of the underlying mechanism will offer deeper insights into identifying novel molecular targets for developing potent therapeutics and biomarkers of disease diagnosis.

Investigation of time profile of FEV1 across the onset of potential COPD: a retrospective cohort study using medical checkup data in Japan

This study compared the time profile of FEV₁ after COPD diagnosis among rapid decliners, slow decliners, and sustainers in the year of COPD diagnosis. COPD subjects were identified from the annual medical checkup records of Hitachi, Ltd., employees in Japan (April 1998-March 2019). Subjects were categorized into 3 groups (rapid decliner [decrease of FEV₁ ≥ 63 mL/year], slow decliner [< 63 and ≥ 31 mL/year], and sustainer [< 31 mL/year]) for 5 years. The time profile of FEV₁ was compared using mixed-effects model for 5 years after diagnosis; risk factors of rapid decliner were detected using logistic model/gradient boosting decision tree. Of 1294 eligible subjects, 18.6%, 25.7%, and 55.7% were classified as rapid decliners, slow decliners, and sustainers, respectively. The annual rates of FEV₁ decline were similar 3 years before and until COPD diagnosis. The mean FEV₁ in rapid decliners was 2.82 ± 0.04 L in year 0 and 2.41 ± 0.05 L in year 5, and in sustainers, it was 2.67 ± 0.02 L and 2.72 ± 0.02 L (year 0, p = 0.0004). In conclusion, FEV₁ declined yearly before diagnosis and the time profiles of FEV₁ were different in the 3 groups after COPD diagnosis. Therefore, appropriate treatment of the 3 groups with regular lung function tests is necessary to follow FEV₁ decline after COPD onset.

Respiratory complications of obesity: from early changes to respiratory failure

Obesity is a significant and increasingly common cause of respiratory compromise. It causes a decrease in static and dynamic pulmonary volumes. The expiratory reserve volume is one of the first to be affected. Obesity is associated with reduced airflow, increased airway hyperresponsiveness, and an increased risk of developing pulmonary hypertension, pulmonary embolism, respiratory tract infections, obstructive sleep apnoea and obesity hypoventilation syndrome. The physiological changes caused by obesity will eventually lead to hypoxic or hypercapnic respiratory failure. The pathophysiology of these changes includes a physical load of adipose tissue on the respiratory system and a systemic inflammatory state. Weight loss has clear, well-defined benefits in improving respiratory and airway physiology in obese individuals.

Outcomes of Patients with Burns Associated with Home Oxygen Therapy: An Institutional Retrospective Review

Home oxygen therapy (HOT) burns carry high morbidity and mortality. Many patients are active smokers, which is the most frequent cause of oxygen ignition. We conducted a retrospective review at our institution to characterize demographics and outcomes in this patient population. An IRB-approved single-institution retrospective review was conducted for home oxygen therapy burn patients between July 2016 and January 2021. Demographic and clinical outcome data were compared between groups. We identified 100 patients with oxygen therapy burns. Mean age was 66.6 years with a male to female ratio of 1.3:1 and median burn surface area of 1%. In these patients, 97% were on oxygen for COPD and smoking caused 83% of burns. Thirteen were discharged from the emergency department, 35 observed for less than 24 hours, and 52 admitted. For admitted patients, 69.2% were admitted to the ICU, 37% required intubation, and 11.5% required debridement and grafting. Inhalational injury was found in 26.9% of patients, 3.9% underwent tracheostomy, and 17.3% experienced hospital complications. In-hospital mortality was 9.6% and 7.7% were discharged to hospice. 13.5% required readmission within 30 days. Admitted patients had significantly higher rates of admission to the ICU, intubation, and inhalational injury compared to those that were not admitted (p &lt; .01). Most HOT-related burns are caused by smoking and can result in significant morbidity and mortality. Efforts to educate and encourage smoking cessation with more judicious HOT allocation would assist in preventing these unnecessary highly morbid injuries.

Predictors of chronic obstructive pulmonary disease in women who never smoked: A cohort study

COPD is responsible for an increasing number of deaths worldwide. Smoking is the most reliable predictor for developing COPD later in life. However, women make up the majority of patients with COPD who have never smoked. There is therefore a need to identify other factors that can predict COPD in women. The aim of this study is to identify factors associated with increasing the risk of developing COPD later in life in women who have never smoked.

Data from the Australian Longitudinal Study on Women's Health (ALSWH) cohort born between 1946 and 1951 were used to investigate potential predictors of COPD. Retrospective analyses were performed on data from two of the ALSWH surveys: wave 1 (1996) and wave 9 (2019).

There were 3584 women who self-reported as being never-smokers (at waves 1 and 9) and did not have COPD at baseline, of which 109 had developed COPD at wave 9. Logistic regression showed a significant relationship between COPD at wave 9 and baseline breathing difficulties (p<0.001), asthma (p<0.001) and allergies (p=0.026), though significance of asthma and allergies disappeared when included together in a single model, implying that women with these symptoms earlier in life were more likely to be diagnosed with COPD later in life compared to women without these symptoms.

Our study supports the inclusion of lung function testing in primary care settings for women over the age of 45 years who have never smoked and have a history of breathing difficulties, asthma or allergies.

A history of breathing difficulties, asthma, allergies, hay fever and sinusitis are associated with an increased risk of developing COPD later in life in women who have never smoked. Lung function testing should be considered for these women.https://bit.ly/3jDX9Mp

Prevalence of obstructive sleep apnea among patients with chronic obstructive pulmonary disease

Background

The conjunction of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) is known as overlap syndrome (OS). The coexistence of these diseases has cardiovascular morbidity and mortality. The aim of this study is to assess the prevalence of OSA in COPD patients. One hundred COPD patients (obese and non-obese) performed sleep questionnaires and polysomnograms.

Results

OSA prevalence in COPD was 50% and it increases with increasing disease severity (P < 0.001). The highest prevalence of OSA was found in obese patients with severe COPD; 90.5% of these patients have OSA. In the OSA group, obese patients were found to have significantly higher STOP-Bang Questionnaire (SBQ), Epworth Sleep Scale (ESS), modified medical research council (mMRC) dyspnea scale, apnea-hypopnea index (AHI), respiratory disturbance index (RDI), and oxygen desaturation index (ODI). Both obese and non-obese COPD patients showed significant positive correlations between AHI and smoking index (SI), SBQ, ESS, mMRC, ODI, and neck circumference (NC).

Conclusions

From this study, it can be concluded that moderate and severe COPD patients had a higher diagnosis of sleep-disordered breathing. Also, obese-COPD patients are more susceptible to develop OSA.

Trial registration

Name of the registry: Benha University Protocol Record Benha U123, Obstructive Sleep Apnea Prevalence in Patients With Chronic Obstructive Pulmonary Diseases. Trial registration number: NCT04903639. Date of registry: 5/22/2021 (retrospective study).

Association of obesity-related inflammatory pathways with lung function and exercise capacity

BACKGROUND

Obesity has multifactorial effects on lung function and exercise capacity. The contributions of obesity-related inflammatory pathways to alterations in lung function remain unclear.

RESEARCH QUESTION

To examine the association of obesity-related inflammatory pathways with pulmonary function, exercise capacity, and pulmonary-specific contributors to exercise intolerance.

METHOD

We examined 695 patients who underwent cardiopulmonary exercise testing (CPET) with invasive hemodynamic monitoring at Massachusetts General Hospital between December 2006-June 2017. We investigated the association of adiponectin, leptin, resistin, IL-6, CRP, and insulin resistance (HOMA-IR) with pulmonary function and exercise parameters using multivariable linear regression.

RESULTS

Obesity-related inflammatory pathways were associated with worse lung function. Specifically, higher CRP, IL-6, and HOMA-IR were associated with lower percent predicted FEV₁ and FVC with a preserved FEV₁/FVC ratio suggesting a restrictive physiology pattern (P ≤ 0.001 for all). For example, a 1-SD higher natural-logged CRP level was associated with a nearly 5% lower percent predicted FEV₁ and FVC (beta -4.8, s.e. 0.9 for FEV1; beta -4.9, s.e. 0.8 for FVC; P < 0.0001 for both). Obesity-related inflammatory pathways were associated with worse pulmonary vascular distensibility (adiponectin, IL-6, and CRP, P < 0.05 for all), as well as lower pulmonary artery compliance (IL-6 and CRP, P ≤ 0.01 for both).

INTERPRETATION

Our findings highlight the importance of obesity-related inflammatory pathways including inflammation and insulin resistance on pulmonary spirometry and pulmonary vascular function. Specifically, systemic inflammation as ascertained by CRP, IL-6 and insulin resistance are associated with restrictive pulmonary physiology independent of BMI. In addition, inflammatory markers were associated with lower exercise capacity and pulmonary vascular dysfunction.

Contemporary perspectives in COPD: Patient burden, the role of gender and trajectories of multimorbidity

An individual's experience of COPD is determined by many factors in addition to the pathological features of chronic bronchitis and emphysema and the symptoms that derive directly from them. Multimorbidity is the norm rather than the exception, so most people with COPD are living with a range of other medical problems which can decrease overall quality of life. COPD is caused by the inhalation of noxious particles or gases, in particular tobacco smoke, but also by early life disadvantage impairing lung development and by occupations where inhaled exposures are common (e.g. industrial, farming and cleaning work). Wealthy people are therefore relatively protected from developing COPD and people who do develop the condition may have reduced resources to cope. COPD is also no longer a condition that predominantly affects men. The prevalence of COPD among women has equalled that of men since 2008 in many high-income countries, due to increased exposure to tobacco, and in low-income countries due to biomass fuels. COPD is one of the leading causes of death in women in the USA, and death rates attributed to COPD in women in some countries are predicted to overtake those of men in the next decade. Many factors contribute to this phenomenon, but in addition to socioeconomic and occupational factors, there is increasing evidence of a higher susceptibility of females to smoking and pollutants. Quality of life is also more significantly impaired in women. Although most medications (bronchodilators and inhaled corticosteroids) used to treat COPD demonstrate similar trends for exacerbation prevention and lung function improvement in men and women, this is an understudied area and clinical trials frequently have a preponderance of males. A better understanding of gender-based predictors of efficacy of all therapeutic interventions is crucial for comprehensive patient care. There is an urgent need to recognize the increasing burden of COPD in women and to facilitate global improvements in disease prevention and management in this specific population. Many individuals with COPD follow a trajectory of both lung function decline and also multimorbidity. Unfavourable lung function trajectories throughout life have implications for later development of other chronic diseases. An enhanced understanding of the temporal associations underlying the development of coexisting diseases is a crucial first step in unravelling potential common disease pathways. Lessons can be learned from exploring disease trajectories of other NCD as well as multimorbidity development. Further research will be essential to explain how early life risk factors commonly influence trajectories of COPD and other diseases, how different diseases develop in relation to each other in a temporal way and how this ultimately leads to different multimorbidity patterns in COPD. This review integrates new knowledge and ideas pertaining to three broad themes (i) the overall burden of disease in COPD, (ii) an unappreciated high burden in women and (iii) the contrast of COPD trajectories and different multimorbidity patterns with trajectories of other NCD. The underlying pathology of COPD is largely irreversible, but many factors noted in the review are potentially amenable to intervention. Health and social care systems need to ensure that effective treatment is accessible to all people with the condition. Preventive strategies and treatments that alter the course of disease are crucial, particularly for patients with COPD as one of many problems.

New Mexico Female Miners Have Lower Odds for COPD than Their Male Counterparts

Chronic obstructive pulmonary disease (COPD) is a significant cause of morbidity among miners. There is an increasing number of women in the mining industry and the differences in their risk for COPD compared to men miners are not understood. Our objective is to compare the odds for COPD between male and female miners. Using cross-sectional data from the Mining Dust in the United States (MiDUS) Cohort, that included New Mexico miners between 1989 and 2018, we compared the odds for airflow obstruction or chronic bronchitis between women and men. There were 299 women in this diverse cohort of 7,464 miners. Compared to men, female miners reported lower cumulative smoking but higher prevalence of current smoking. Multivariable analysis showed that women miners had significantly lower odds for having airflow obstruction (OR 0.40; 95% CI (0.26, 0.6)) and chronic bronchitis (OR 0.31, 95% CI (0.19, 0.53)) than men. Future studies need to determine whether this sex difference is explained by residual confounders or true biological difference.

Lung Function Decline in Farm and Nonfarm Rural Residents of Saskatchewan

OBJECTIVE

This study aims to assess the annual changes in lung function among farm and nonfarm adult residences in rural Saskatchewan, Canada.

METHODS

Data from the Saskatchewan Rural Health Study survey (2010 to 2014) among 724 adults were used.

RESULTS

For forced expiratory volume in 1 second (FEV1) measurements, estimates of annual decline (in milliliters) were highest in older age male (65+ years) (Mean, SD) (-42.63, 21.16); and among old heavy smokers (-57.79, 24.30). Estimates of annual decline in forced vital capacity (FVC) were highest in current smokers without the use of natural gas (-25.78, 14.78) and among old heavy smokers (-33.88, 20.28). Living on a farm is associated with decreased FEV1 and FVC, but not statistically significant by sex and age.

CONCLUSIONS

A complex mix of personal and contextual factors may affect these estimates.

Clinical Characteristics of Chronic Obstructive Pulmonary Disease in Female Patients: Findings from a KOCOSS Cohort

PURPOSE

The prevalence of chronic obstructive pulmonary disease (COPD) in females has increased, changing the concept of COPD as a disease mostly limited to males. In this study, the clinical characteristics of COPD in females were investigated.

PATIENTS AND METHODS

The study was based on a multicenter cohort of COPD patients recruited from 54 medical centers in South Korea. Sex-based differences in general characteristics, exposure risk factors, depression scores, results of pulmonary function tests, COPD exacerbation, symptom scores, and radiologic findings were evaluated. Sex-related differences in the annual FEV₁ change over 5 years were analyzed in a linear mixed model.

RESULTS

Of the 2515 patients enrolled in this study, 8.1% were female. Female patients who had a higher BMI and a lower level of education were less likely to be smokers, were more exposed to passive smoking/biomass, and were more depressed compared to males. The rates of bronchiectasis, previous childhood respiratory infection, and asthma were higher in females. Female patients also had more symptoms and a poorer exercise capacity than males, but no significant differences were observed in terms of exacerbations. Radiologic findings revealed that male patients had worse emphysema, and female patients had worse bronchiectasis, as determined based on chest X-ray and computed tomography findings. On pulmonary function tests, female patients had less obstruction and less annual FEV₁ loss over 5 years.

CONCLUSION

This study revealed differences in the clinical parameters between male and female patients with COPD, including general characteristics, disease characteristics, and clinical outcomes.

Rate of Forced Expiratory Volume in One Second and Forced Expiratory Volume in One Second/Forced Vital Capacity Decline among Indonesian Patients with Chronic Obstructive Pulmonary Disease after a Year of Treatment

Background:

The rate of decline in lung function in chronic obstructive pulmonary disease (COPD) patients showed more profound decline than normal individuals. However, a 1-year lung function among Indonesian patients with COPD has not been elucidated.

Aim:

This study attempted to determine the rate of lung function decline in terms of obstruction variable among COPD patients after a 1-year of treatment.

Materials and Methods:

This retrospective cohort study measures the rate of decline in forced expiratory volume in 1 s (FEV1) and ratio of FEV1 to forced vital capacity (FEV1/FVC) in COPD patients at COPD Outpatient Clinic Persahabatan Hospital after 1-year of treatment.

Results:

There were 31 COPD patients with the prevalence of 1-year declined FEV1 and FEV1/FVC which were 83.9% and 51.6%, respectively. Among 1-year declined lung function group, there were significant (P < 0.05) decline in FEV1 (121.53 ± 120 ml/year) and in FEV1/FVC (2.75 ± 0.47%). The rate of decline in FEV1 was more prevalent in Group D, while the rate of decline in FEV1/FVC was more prevalent in Group B. No significant associations were found between sex, age, respiratory complaints, smoking history, Brinkman index, type of cigarette, comorbid, educational level, diagnosed age, body mass index, symptoms-based COPD classification, and risk-based COPD classification, with the rate of decline in FEV1 and FEV1/FVC.

Conclusions:

Most patients had statistically significant rate of decline in FEV1 and FEV1/FVC within 1-year of COPD treatment. This study recognized an unfavorable prognosis in terms of irreversible deteriorating lung function of COPD patients despite therapeutic management.

Iron deficiency as energetic insult to skeletal muscle in chronic diseases

Specific skeletal myopathy constitutes a common feature of heart failure, chronic obstructive pulmonary disease, and type 2 diabetes mellitus, where it can be characterized by the loss of skeletal muscle oxidative capacity. There is evidence from in vitro and animal studies that iron deficiency affects skeletal muscle functioning mainly in the context of its energetics by limiting oxidative metabolism in favour of glycolysis and by alterations in both carbohydrate and fat catabolic processing. In this review, we depict the possible molecular pathomechanisms of skeletal muscle energetic impairment and postulate iron deficiency as an important factor causally linked to loss of muscle oxidative capacity that contributes to skeletal myopathy seen in patients with heart failure, chronic obstructive pulmonary disease, and type 2 diabetes mellitus.

Statins dose-dependently exert a significant chemopreventive effect on colon cancer in patients with chronic obstructive pulmonary disease: A population-based cohort study

Purpose

We evaluated the chemopreventive effect of statins on colon cancer in patients with chronic obstructive pulmonary disease (COPD) and identified the statin exerting the strongest chemopreventive effect.

Methods

Using the National Health Insurance Research Database, we identified patients who received a COPD diagnosis in Taiwan between January 1, 2001, and December 31, 2012, and included them in the study cohort. Each patient was followed to assess the colon cancer risk and protective factors. A propensity score was derived using a logistic regression model to estimate the effect of statins by accounting for covariates predicted during the intervention (statins). To examine the dose–response relationship, we categorized statin doses into four groups in each cohort [<28, 28–90, 91–365, and >365 cumulative defined daily dose].

Results

Compared with the statin nonusers, the adjusted hazard ratio (aHR) for colon cancer decreased in the statin users (aHR = 0.52, 95% confidence interval = 0.44, 0.62). Hydrophilic statins exerted a stronger preventive effect against colon cancer. Regarding the statin type, lovastatin, pravastatin, and fluvastatin nonsignificantly reduced the colon cancer risk in the patients with COPD. Compared with the statin nonusers, the aHRs for colon cancer decreased in the individual statin users (rosuvastatin, simvastatin, and atorvastatin: aHRs = 0.28, 0.64, and 0.65, respectively). In the sensitivity analysis, statins dose-dependently reduced the colon cancer risk.

Conclusions

Statins dose-dependently exert significant chemopreventive effects on colon cancer in patients with COPD, with rosuvastatin exerting the largest chemopreventive effect.

Health at Every Size

It would be difficult to overstate the urgency that U.S. government and health officials have placed on the dangers posed by obesity. Given the increasing numbers of individuals being diagnosed as overweight and obese and the emphasis on the contribution of weight to health and disease, it is critical that all health professionals examine the validity of the claims being made. A thorough examination of the research literature does not support the claims that overweight and obesity are major causes of premature mortality, excess fat is pathological and a direct cause of disease, and weight loss is practical and beneficial to health for most individuals. The literature also does not provide any significant evidence-based support for current approaches to weight management. In fact, it suggests that these approaches may likely be doing more harm than good.

Statins Dose-Dependently Exert Significant Chemopreventive Effects Against Various Cancers in Chronic Obstructive Pulmonary Disease Patients: A Population-Based Cohort Study

PURPOSE: Chronic obstructive pulmonary disease (COPD) is associated with an increased cancer risk. We evaluated the chemopreventive effect of statins against all cancers in COPD patients and identified the statin with the strongest chemopreventive effect. PATIENTS AND METHODS: All patients diagnosed with COPD at health care facilities in Taiwan (n = 116,017) from January 1, 2001, to December 31, 2012, were recruited. Each patient was followed to assess the following protective and risk factors for all cancers: age; sex; comorbidities (diabetes, hypertension, dyslipidemia) and the Charlson comorbidity index [CCI]); urbanization level; monthly income; and nonstatin drug use. The index date of statins use was the date of COPD confirmation. Propensity scores (PSs) were derived using a logistic regression model to estimate the effect of statins by considering the covariates predicting intervention (statins) receipt. To examine the dose-response relationship, we categorized statin use into four groups in each cohort (<28 [statin nonusers], 28-90, 91-365, and >365 cumulative defined daily dose). RESULTS: After PS adjustment for age, sex, CCI, diabetes, hypertension, dyslipidemia, urbanization level, and monthly income, we analyzed the all-cancer risk. The adjusted hazard ratios (aHRs) for the all-cancer risk were lower among statin users than among statin nonusers (aHR = 0.46, 95% confidence interval: 0.43 to 0.50). The aHRs for the all-cancer risk were lower among patients using rosuvastatin, simvastatin, atorvastatin, pravastatin, and fluvastatin than among statin nonusers (aHRs = 0.42, 0.55, 0.59, 0.66, and 0.78, respectively). Sensitivity analysis indicated that statins dose-dependently reduced the all-cancer risk. CONCLUSION: Statins dose-dependently exert a significant chemopreventive effect against various cancers in COPD patients. In particular, rosuvastatin has the strongest chemopreventive effect.

Sex Difference in Chronic Obstructive Lung Disease. Does it Matter? A Concise Review

Chronic obstructive lung disease (COPD) primarily affects men; however, its epidemiology has been changing because more women have become smokers. Recently, investigators found that although women and men were exposed to the same amount of smoke fume, women tended to have more severe disease and higher mortality rate. They also complain of more dyspnoea and may experience more severe exacerbations than men. This led to the question of whether sex has an impact on COPD course and whether women have a higher susceptibility to smoke fumes than men. That may be explained by multiple complex factors highlighting the relationship between sex, epidemiology, method of diagnostics and the clinical course of the disease. In this review, sex differences in epidemiology, clinical presentation, exacerbation, co-morbidities and treatment are covered.

Symptoms and lung function decline in a middle-aged cohort of males and females in Australia

BACKGROUND

The European Community Respiratory Health Survey is a major international study designed to assess lung health in adults. This Australian follow-up investigated changes in symptoms between sexes and the roles of asthma, smoking, age, sex, height, and change in body mass index (ΔBMI) on lung function decline (LFD), which is a major risk factor for chronic obstructive pulmonary disease (COPD).

METHODS

LFD was measured as the rate of decline over time in FEV1 (mL/year) (ΔFEV1) and FVC (ΔFVC) between 1993 and 2013. Multiple linear regression was used to estimate associations between risk factors and LFD, separately for males and females. Multiple logistic regression was used to assess sex differences and changes in respiratory symptoms over time.

RESULTS

In Melbourne, 318 subjects (53.8% females) participated. The prevalence of most respiratory symptoms had either remained relatively stable over 20 years or decreased (significantly so for wheeze). The exception was shortness of breath after activity, which had increased. Among the 262 subjects who completed spirometry, current smoking declined from 20.2% to 7.3%. Overall mean (± standard deviation) FEV1 declined by 23.1 (±17.1) and FVC by 22.9 (±20.2) mL/year. Predictors of ΔFEV1 in males were age, maternal smoking, and baseline FEV1; and in females they were age, ΔBMI, baseline FEV1, and pack-years in current smokers. Decline in FVC was predicted by baseline FVC, age, and ΔBMI in both sexes; however, baseline FVC predicted steeper decline in females than males.

CONCLUSION

Most respiratory symptoms remained stable or decreased over time in both sexes. Age, baseline lung function, and change in BMI were associated with the rate of decline in both sexes. However, obesity and personal smoking appear to put females at higher risk of LFD than males. Health promotion campaigns should particularly target females to prevent COPD.

Gender and asthma-chronic obstructive pulmonary disease overlap syndrome

OBJECTIVE

To assess relationships between obstructive lung diseases, respiratory symptoms, and comorbidities by gender.

METHODS

Data from 12 594 adult respondents to the 2012 South Carolina Behavioral Risk Factor Surveillance System telephone survey were used. Five categories of chronic obstructive airway disease (OAD) were defined: former asthma only, current asthma only, chronic obstructive pulmonary disease (COPD) only, asthma-COPD overlap syndrome (ACOS), and none. Associations of these categories with respiratory symptoms (frequent productive cough, shortness of breath, and impaired physical activities due to breathing problems), overall health, and comorbidities were assessed using multivariable logistic regression for men and women.

RESULTS

Overall, 16.2% of men and 18.7% of women reported a physician diagnosis of COPD and/or asthma. Former asthma only was higher among men than women (4.9% vs. 3.2%, t-test p = 0.008). Current asthma only was more prevalent among women than men (7.2% vs. 4.7%, p < 0.001), as was ACOS (4.0% vs. 2.2%, p < 0.001). Having COPD only did not differ between women (4.3%) and men (4.4%). Adults with ACOS were most likely to report the 3 respiratory symptoms. COPD only and ACOS were associated with higher likelihoods of poor health and most comorbidities for men and women. Current asthma only was also associated with these outcomes among women, but not among men.

CONCLUSIONS

In this large population-based sample, women were more likely than men to report ACOS and current asthma, but not COPD alone. Gender differences were evident between the OAD groups in sociodemographic characteristics, respiratory symptoms, and comorbidities, as well as overall health.

Bronchodilator response in adults with bronchiectasis: correlation with clinical parameters and prognostic implications

BACKGROUND

Bronchial dilation testing is an important tool to assess airway reversibility in adults with bronchiectasis. This study aims to investigate the association of bronchodilator response (BDR) and clinical parameters in bronchiectasis, and the utility of BDR to indicate lung function decline and risks of bronchiectasis exacerbations (BEs).

METHODS

We recruited 129 patients with clinically stable bronchiectasis. Baseline measurements included assessment of sputum inflammation and matrix metalloproteinase-8 and -9, sputum bacterial culture, spirometry, bronchial dilation test (for baseline FEV1 less than 80% predicted only) and chest high-resolution computed tomography (HRCT). Bronchiectasis patients were followed-up for 1 year to determine the incidence of BEs and lung function trajectories. Significant BDR was defined as FEV1 improvement from pre-dose value by at least 200 mL and 12%. Clinical trial registry No.: NCT01761214; URL: www.clinicaltrials.gov.

RESULTS

BDR was negatively correlated with baseline FEV1 percentage predicted, but not blood or sputum eosinophil count. Significant BDR was not associated with greater proportion of never-smokers, poorer past history, greater HRCT scores, poorer diffusing capacity or increased sputum matrix metalloproteinases (all P>0.05). There was a trend towards higher bronchiectasis severity index (BSI) and greater proportion of patients with Pseudomonas aeruginosa isolation or infection. Significant BDR at baseline was linked to poorer spirometry, but not more rapid lung function decline, throughout follow-up. Patients with significant BDR demonstrated non-significantly lower risks of experiencing the first BEs than those without (P=0.09 for log-rank test).

CONCLUSIONS

Significant BDR is associated with poorer lung function compared with non-significant BDR. Whether BDR predicts future risks of BEs needs to be tested in a larger cohort.

Development and Validation of a Predictive Model to Identify Individuals Likely to Have Undiagnosed Chronic Obstructive Pulmonary Disease Using an Administrative Claims Database

BACKGROUND

Despite the importance of early detection, delayed diagnosis of chronic obstructive pulmonary disease (COPD) is relatively common. Approximately 12 million people in the United States have undiagnosed COPD. Diagnosis of COPD is essential for the timely implementation of interventions, such as smoking cessation programs, drug therapies, and pulmonary rehabilitation, which are aimed at improving outcomes and slowing disease progression.

OBJECTIVE

To develop and validate a predictive model to identify patients likely to have undiagnosed COPD using administrative claims data.

METHODS

A predictive model was developed and validated utilizing a retro-spective cohort of patients with and without a COPD diagnosis (cases and controls), aged 40-89, with a minimum of 24 months of continuous health plan enrollment (Medicare Advantage Prescription Drug [MAPD] and commercial plans), and identified between January 1, 2009, and December 31, 2012, using Humana's claims database. Stratified random sampling based on plan type (commercial or MAPD) and index year was performed to ensure that cases and controls had a similar distribution of these variables. Cases and controls were compared to identify demographic, clinical, and health care resource utilization (HCRU) characteristics associated with a COPD diagnosis. Stepwise logistic regression (SLR), neural networking, and decision trees were used to develop a series of models. The models were trained, validated, and tested on randomly partitioned subsets of the sample (Training, Validation, and Test data subsets). Measures used to evaluate and compare the models included area under the curve (AUC); index of the receiver operating characteristics (ROC) curve; sensitivity, specificity, positive predictive value (PPV); and negative predictive value (NPV). The optimal model was selected based on AUC index on the Test data subset.

RESULTS

A total of 50,880 cases and 50,880 controls were included, with MAPD patients comprising 92% of the study population. Compared with controls, cases had a statistically significantly higher comorbidity burden and HCRU (including hospitalizations, emergency room visits, and medical procedures). The optimal predictive model was generated using SLR, which included 34 variables that were statistically significantly associated with a COPD diagnosis. After adjusting for covariates, anticholinergic bronchodilators (OR = 3.336) and tobacco cessation counseling (OR = 2.871) were found to have a large influence on the model. The final predictive model had an AUC of 0.754, sensitivity of 60%, specificity of 78%, PPV of 73%, and an NPV of 66%.

CONCLUSIONS

This claims-based predictive model provides an acceptable level of accuracy in identifying patients likely to have undiagnosed COPD in a large national health plan. Identification of patients with undiagnosed COPD may enable timely management and lead to improved health outcomes and reduced COPD-related health care expenditures.

The chronic obstructive pulmonary disease comorbidity spectrum in Japan differs from that in western countries

Patients with Chronic Obstructive Pulmonary Disease (COPD) frequently suffer from various comorbidities, such as cardiovascular disease, osteoporosis, depression, malnutrition, metabolic syndrome, diabetes, and lung cancer. These comorbidities have a significant impact on disease severity and survival. In fact, guidelines from both the Global Initiative for Chronic Obstructive Lung Disease and the Japanese Respiratory Society recommend that physicians take comorbidities into account when they evaluate COPD severity. These guidelines also emphasize the importance of managing comorbidities alongside airway obstruction in COPD. The mechanisms by which the many COPD-related comorbidities develop are still unclear. Aging and smoking are well-established as major factors. However, systemic inflammation may also contribute to the disease process. Having developed from the classical theory to differentiate COPD patients into "pink puffers" and "blue bloaters", COPD is now generally considered as a heterogeneous condition. On this point, we have noticed that the characteristics of Japanese COPD patients tend to differ from those of Westerners. Specifically, Japanese patients tend to be older, to have lower body mass index, to suffer from emphysema-dominant lung disease, and to experience exacerbations less frequently. The comorbidity spectrum of Japanese COPD patients also seems to differ from that of Westerners. For instance, in Japanese patients, cardiovascular disease and metabolic syndrome are less prevalent, whereas osteoporosis and malnutrition are more frequent. In order to treat Japanese COPD patients optimally, we must pay particular attention to their unique demographics and comorbidity spectrum, which contrast with those of Western COPD patients.

Paradoxical association between body mass index and in-hospital mortality in elderly patients with chronic obstructive pulmonary disease in Japan

Background and objective

The prevalence and mortality of chronic obstructive pulmonary disease (COPD) in elderly patients are increasing worldwide. Low body mass index (BMI) is a well-known prognostic factor for COPD. However, the obesity paradox in elderly patients with COPD has not been well elucidated. We investigated the association between BMI and in-hospital mortality in elderly COPD patients.

Methods

Using the Diagnosis Procedure Combination database in Japan, we retrospectively collected data for elderly patients (>65 years) with COPD who were hospitalized between July 2010 and March 2013. We performed multivariable logistic regression analysis to compare all-cause in-hospital mortality between patients with BMI of <18.5 kg/m² (underweight), 18.5–22.9 kg/m² (low–normal weight), 23.0–24.9 kg/m² (high–normal weight), 25.0–29.9 kg/m² (overweight), and ≥30.0 kg/m² (obesity) with adjustment for patient backgrounds.

Results

In all, 263,940 eligible patients were identified. In-hospital mortality was 14.3%, 7.3%, 4.9%, 4.3%, and 4.4%, respectively, in underweight, low–normal weight, high–normal weight, overweight, and obese patients. Underweight patients had a significantly higher mortality than low–normal weight patients (odds ratio [OR]: 1.55, 95% confidence interval [CI]: 1.48–1.63), whereas lower mortality was associated with high–normal weight (OR: 0.76, CI: 0.70–0.82), overweight (OR: 0.73, CI: 0.66–0.80), and obesity (OR: 0.67, CI: 0.52–0.86). Higher mortality was significantly associated with older age, male sex, more severe dyspnea, lower level of consciousness, and lower activities of daily living.

Conclusion

Overweight and obese patients had a lower mortality than low–normal weight patients, which supports the obesity paradox.

Association between smoking habits and the first-time appearance of atrial fibrillation in Japanese patients: Evidence from the Shinken Database

BACKGROUND

We previously reported a cross-sectional analysis regarding the relationship between smoking and atrial fibrillation (AF) in a single hospital-based cohort with Japanese patients, but the effect of cessation of smoking and/or total tobacco consumption were unclear.

METHODS AND RESULTS

We used data from the Shinken Database 2004-2011 (men/women, n=10,714/6803, respectively), which included all new patients attending the Cardiovascular Institute between June 2004 and March 2012. After excluding those previously diagnosed with AF (n=2296), 15,221 patients (men/women, n=9016/6205) were analyzed. During the follow-up period of 2.0±2.1 years (range 0.0-8.1), the incidence rates of new AF in smokers and non-smokers were 9.0 and 5.0 per 1000 patient-years, respectively. In adjusted models with Cox regression analysis, smokers were independently associated with new AF [hazard ratio (HR) 1.47, 95% confidence interval (CI) 1.09-2.00]. Also, current smokers (HR 1.81, 95% CI 1.17-2.79) and smokers with Brinkman index ≥800 (HR 1.69, 95% CI 1.05-2.70) were independently associated with new AF. However, in current smokers, the HRs were not different by Brinkman index (Brinkman index <800/≥800; HR 1.81/1.82, 95% CI 1.07-3.05/0.94-3.51, respectively).

CONCLUSIONS

Smoking was independently associated with the first-appearance of AF in patients in sinus rhythm, especially when the patients continued their smoking habit. However, in patients who continued smoking, difference by total tobacco consumption was not observed, suggesting the significance of cessation of smoking for preventing AF. Our data are limited because of a single hospital-based nature and a relatively short observation period.

Influence of sex on chronic obstructive pulmonary disease risk and treatment outcomes

Chronic obstructive pulmonary disease (COPD), one of the most common chronic diseases and a leading cause of death, has historically been considered a disease of men. However, there has been a rapid increase in the prevalence, morbidity, and mortality of COPD in women over the last two decades. This has largely been attributed to historical increases in tobacco consumption among women. But the influence of sex on COPD is complex and involves several other factors, including differential susceptibility to the effects of tobacco, anatomic, hormonal, and behavioral differences, and differential response to therapy. Interestingly, nonsmokers with COPD are more likely to be women. In addition, women with COPD are more likely to have a chronic bronchitis phenotype, suffer from less cardiovascular comorbidity, have more concomitant depression and osteoporosis, and have a better outcome with acute exacerbations. Women historically have had lower mortality with COPD, but this is changing as well. There are also differences in how men and women respond to different therapies. Despite the changing face of COPD, care providers continue to harbor a sex bias, leading to underdiagnosis and delayed diagnosis of COPD in women. In this review, we present the current knowledge on the influence of sex on COPD risk factors, epidemiology, diagnosis, comorbidities, treatment, and outcomes, and how this knowledge may be applied to improve clinical practices and advance research.

Influence of diet and obesity on COPD development and outcomes

The global increase in the prevalence and incidence of obesity has called serious attention to this issue as a major public health concern. Obesity is associated with many chronic diseases, including cardiovascular disease and diabetes, and recently the role of overweight and obesity in lung disease has received new interest. Independently of obesity, diet also plays a role as a risk factor for many chronic diseases, and evidence is accumulating to support a role for diet in the prevention and management of several lung diseases. Chronic obstructive lung disease is the third-leading cause of death globally, and both obesity and diet appear to play roles in its pathophysiology. Obesity has been associated with decreased lung-function measures in population-based studies, with increased prevalence of several lung diseases and with compromised pulmonary function. In contrast, obesity has a protective effect against mortality in severe chronic obstructive pulmonary disease (COPD). Nutrient intake and dietary patterns have also been associated with lung-function measures and the development and progression of COPD. Taken together, this suggests that a focus on obesity and diet should be part of public health campaigns to reduce the burden of lung disease, and could have important implications for clinicians in the management of their patients. Future research should also focus on elucidating these relationships in diverse populations and age-groups, and on understanding the complex interaction between behavior, environment, and genetics in the development and progression of COPD. The goal of this article is to review current evidence regarding the role that obesity and diet play in the development of COPD, and in COPD-related outcomes.

Gender Differences in Pulmonary Function, Respiratory Symptoms, and Macrophage Proteomics among HIV-Infected Smokers

Background. HIV-infected subjects have an increased incidence of pulmonary emphysema. There are known gender differences in COPD phenotypic expression and diagnosis, but this is not well characterized in lung disease related to HIV. We analyzed a group at risk for the development of COPD (HIV-infected smokers) to determine gender differences in pulmonary symptoms, pulmonary function tests, and HRCT appearances. Methods. This was a cross-sectional, baseline analysis of a prospective study performed between 2006 and 2010. We performed symptomatic, pulmonary function, and computed tomography assessments in 243 HIV-infected smokers. In a subset bronchoalveolar lavage was performed with proteomic analysis of their alveolar macrophages. Results. The majority of the participants were male 213 (87.6%). There was significantly higher percentage of cough and phlegm production in males. There was also a lower FEV1 and a higher RV in males than females. Proteomic analysis revealed 29 proteins with at least a 2-fold higher expression in males and 13 identified proteins that were higher in females. Conclusions. In this group of HIV-infected smokers, airway symptoms and pulmonary function test abnormalities were higher in men than women. These gender differences may be due to differential expression of certain proteins in this group.

COPD and gender differences: an update

Chronic obstructive lung disease (COPD) is one of the most prevalent health conditions, and a major cause of morbidity and mortality around the globe. Once thought of primarily as a disease of men, COPD is now known to be increasingly prevalent among women. Although increasing tobacco consumption among women during the past several decades might explain some of this increase, the relationship may be more complex, including factors such as differential susceptibility to tobacco, anatomic and hormonal differences, behavioral differences, and differences in response to available therapeutic modalities. Moreover, women with COPD may present differently, may have a different pattern of comorbidities, and may have a better survival after acute exacerbations. Care providers continue to have a gender bias that may affect both diagnosis and treatment. Future work should focus on factors that lead to gender differences in COPD as well as gender-specific treatment strategies.

Effects of smoking habit on the prevalence of atrial fibrillation in Japanese patients with special reference to sex differences

BACKGROUND

Tobacco smoking is a well-known risk factor for cardiovascular disease, but controversial results have been reported regarding its relationship with atrial fibrillation (AF). Moreover, no study on the relationship between smoking and AF has yet been undertaken in a Japanese context.

METHODS AND RESULTS

We used data from the Shinken Database 2004-2011 (men/women, n=10,714/6,803, respectively), which included all new patients attending the Cardiovascular Institute between June 2004 and March 2012. AF was diagnosed in 1,698 and 598 men and women, respectively. In men, smokers were more prevalent in the AF than in the non-AF group (54.5% vs. 44.7%), whereas in women the prevalence of smokers was similar between AF and non-AF groups (14.4% vs. 15.4%). This discrepancy between the sexes seems to derive from a characteristic distribution pattern of smoking habit in women. After adjustment for various cofactors, smoking was independently associated with AF (odds ratio 1.54; 95% confidence interval 1.35-1.75; P<0.001) without a significant interaction between sex categories (P=0.195).

CONCLUSIONS

Smoking was independently associated with AF without a significant interaction between sex categories among Japanese patients visiting a cardiovascular hospital. Further studies using a prospective cohort design are required to confirm a causal link between smoking and AF in Japanese patients.

Bayesian predictors of very poor health related quality of life and mortality in patients with COPD

Background

Chronic obstructive pulmonary disease (COPD) is associated with increased mortality and poor health-related quality of life (HRQoL) compared with the general population. The objective of this study was to identify clinical characteristics which predict mortality and very poor HRQoL among the COPD population and to develop a Bayesian prediction model.

Methods

The data consisted of 738 patients with COPD who had visited the Pulmonary Clinic of the Helsinki and Turku University Hospitals during 1995–2006. The data set contained 49 potential predictor variables and two outcome variables: survival (dead/alive) and HRQoL measured with a 15D instrument (very poor HRQoL < 0.70 vs. typical HRQoL ≥ 0.70).

In the first phase of model validation we randomly divided the material into a training set (n = 538), and a test set (n = 200). This procedure was repeated ten times in random fashion to obtain independently created training sets and corresponding test sets. Modeling was performed by using the training set, and each model was tested by using the corresponding test set, repeated in each training set. In the second phase the final model was created by using the total material and eighteen most predictive variables. The performance of six logistic regressions approaches were shown for comparison purposes.

Results

In the final model, the following variables were associated with mortality or very poor HRQoL: age at onset, cerebrovascular disease, diabetes, alcohol abuse, cancer, psychiatric disease, body mass index, Forced Expiratory Volume (FEV₁) % of predicted, atrial fibrillation, and prolonged QT time in ECG. The prediction accuracy of the model was 77%, sensitivity 0.30, specificity 0.95, positive predictive value 0.68, negative predictive value 0.78, and area under the ROC curve 0.69. While the sensitivity of the model reminded limited, good specificity, moderate accuracy, comparable or better performance in classification and better performance in variable selection and data usage in comparison to the logistic regression approaches, and positive and negative predictive values indicate that the model has potential in predicting mortality and very poor HRQoL in COPD patients.

Conclusion

We developed a Bayesian prediction model which is potentially useful in predicting mortality and very poor HRQoL in patients with COPD.

Atopy is a risk factor for respiratory symptoms in COPD patients: results from the EUROSCOP study

BACKGROUND

The pathogenesis of COPD is complex and remains poorly understood. The European Respiratory Society Study on Chronic Obstructive Pulmonary Disease (EUROSCOP) investigated long-term effects of budesonide; 18% of the COPD participants were atopic. So far effects of atopy on the long-term course of COPD have not been elucidated.

METHODS

Factors related to the presence of atopy (positive phadiatop) in 1277 mild-to-moderate COPD patients participating in EUROSCOP were analysed using regression analysis. Incidence and remission of respiratory symptoms during 3-year follow-up were analysed using generalised estimating equations models, and association of atopy with lung function decline using linear mixed effects models.

RESULTS

Independent predisposing factors associated with the presence of atopy were: male gender (OR: 2.21; 95% CI: 1.47-3.34), overweight/obese (OR: 1.41; 95% CI: 1.04-1.92) and lower age (OR: 0.98; 95% CI: 0.96-0.99). Atopy was associated with a higher prevalence of cough (OR: 1.71; 95% CI: 1.26-2.34) and phlegm (OR: 1.50; 95% CI: 1.10-2.03), but not with lung function levels or FEV1 decline. Atopic COPD patients not treated with budesonide had an increased incidence of cough over time (OR: 1.79, 95% CI: 1.03-3.08, p = 0.038), while those treated with budesonide had increased remission of cough (OR: 1.93, 95% CI: 1.11-3.37, p = 0.02) compared to non-atopic COPD patients.

CONCLUSIONS

Atopic COPD patients are more likely male, have overweight/obesity and are younger as compared with non-atopic COPD patients. Atopy in COPD is associated with an increased incidence and prevalence of respiratory symptoms. If atopic COPD patients are treated with budesonide, they more often show remission of symptoms compared to non-atopic COPD patients who are treated with budesonide. We recommend including atopy in the diagnostic work-up and management of COPD.

Rationale for earlier treatment in COPD: a systematic review of published literature in mild-to-moderate COPD

COPD is progressive and typically begins many years before a definite diagnosis is made. As the rate of decline in lung function may be faster in the initial stages of the disease, early intervention could be beneficial to control symptoms and affect disease progression and outcomes. A systematic review of published literature relating to mild-to-moderate COPD (patients with FEV(1) ≥50% predicted) was performed to evaluate the level of impairment and natural history or disease progression over time, and impact of interventions on the outcomes of patients with early-stage disease. Of the 79 published articles included in this analysis, 31 reported randomized controlled trials; the remaining 48 articles reported studies of non-randomized and/or observational design. Nine of the randomized controlled trials were ≥6 months' duration, enabling assessment of outcomes over time. Most of the randomized controlled trials were in patients with moderate COPD (GOLD stage II); few included patients with the mildest stages of the disease (i.e., stage I). The results show that even patients with milder or moderate COPD can have substantial limitations and physical impairment, which worsen over time. Encouragement of smoking cessation, in conjunction with management of symptoms and treating activity limitation and exacerbations by appropriate non-pharmacologic and pharmacologic management at the earliest possible stage, could positively affect the impact and progression of the disease.

Chronic obstructive pulmonary disease and glucose metabolism: a bitter sweet symphony

Chronic obstructive pulmonary disease, metabolic syndrome and diabetes mellitus are common and underdiagnosed medical conditions. It was predicted that chronic obstructive pulmonary disease will be the third leading cause of death worldwide by 2020. The healthcare burden of this disease is even greater if we consider the significant impact of chronic obstructive pulmonary disease on the cardiovascular morbidity and mortality. Chronic obstructive pulmonary disease may be considered as a novel risk factor for new onset type 2 diabetes mellitus via multiple pathophysiological alterations such as: inflammation and oxidative stress, insulin resistance, weight gain and alterations in metabolism of adipokines. On the other hand, diabetes may act as an independent factor, negatively affecting pulmonary structure and function. Diabetes is associated with an increased risk of pulmonary infections, disease exacerbations and worsened COPD outcomes. On the top of that, coexistent OSA may increase the risk for type 2 DM in some individuals. The current scientific data necessitate a greater outlook on chronic obstructive pulmonary disease and chronic obstructive pulmonary disease may be viewed as a risk factor for the new onset type 2 diabetes mellitus. Conversely, both types of diabetes mellitus should be viewed as strong contributing factors for the development of obstructive lung disease. Such approach can potentially improve the outcomes and medical control for both conditions, and, thus, decrease the healthcare burden of these major medical problems.

Optimal duration of pulmonary rehabilitation for individuals with chronic obstructive pulmonary disease - a systematic review

The purpose of this review was to determine the impact of duration of pulmonary rehabilitation on measures of health-related quality of life and exercise tolerance in individuals with chronic obstructive pulmonary disease (COPD). Randomized controlled trials (RCTs) comparing different lengths of pulmonary rehabilitation in patients with COPD were identified after searches of six electronic databases (MEDLINE, PubMed, CINAHL, EMBASE, Physiotherapy Evidence Database [PEDro] and the Cochrane Library of clinical trials) and reference lists of pertinent articles. Two reviewers performed the searches and assessed trial quality using PEDro and Jadad scales. Five RCTs met inclusion criteria. The mean PEDro score was 6 (range 3-8) and mean Jadad was 2 (range 1-3). Three trials reported a difference in health-related quality of life in favour of the longer duration program; two trials reported a benefit in exercise capacity in favour of longer programs. A meta-analysis of results was not possible due to considerable heterogeneity in program duration and outcomes. Longer duration pulmonary rehabilitation programs appear to have a more favourable effect on health-related quality of life in individuals with COPD; results for exercise capacity are less clear. The limited literature prevents a more definitive conclusion on optimal duration of rehabilitation.

Changing patterns in long-acting bronchodilator trials in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide. Developments in the understanding of COPD have led to standard guidelines for diagnosis, treatment, and spirometry assessments, which have in turn influenced trial designs and inclusion criteria. Substantial clinical evidence has been gained from clinical trials and supports a positive approach to COPD management. However, there appear to be changing trends in recent trials. Large bronchodilator studies have reported lower improvements in trough forced expiratory volume in 1 second (FEV(1)) values versus placebo than were observed in earlier studies, while the rate of FEV(1) decline seems to be lower in more recent trials. In addition, recent evidence has called into question the usefulness of bronchodilator reversibility testing as a trial inclusion criterion. Baseline patient populations and use of concomitant medications have also changed over recent years due to increased treatment options. The impact of these many variables on clinical trial results is explored, with a particular focus on changes in inclusion criteria and patient baseline demographics.

Increasing Evidence for Gender Differences in Chronic Obstructive Pulmonary Disease

The prevalence of chronic obstructive pulmonary disease (COPD) among women is increasing and differences in both the management of COPD and the results of treatment between men and women have been noted. This article investigates the reasons for this increase in prevalence and the differences in natural history and COPD management between male and female patients. The main reason for the rise in prevalence of COPD in women is increased tobacco use. An additional factor is the greater susceptibility of women to damage from smoke and air pollution. The health-related quality of life is worse in women when compared with men with the same severity of disease. In addition, nutritional status is often worse in women. The most important treatment for COPD is to stop smoking. Women appear to be more dependent on cigarettes than men, and have greater difficulties stopping smoking, especially when they live with a partner who smokes. Rehabilitation is an effective treatment for both male and female COPD patients, but the focus is different: women need more emotional support and social interaction to achieve the best results.

Gender influences Health-Related Quality of Life in IPF

BACKGROUND

HRQL in IPF patients is impaired. Data from other respiratory diseases led us to hypothesize that significant gender differences in HRQL in IPF also exist.

METHODS

Data were drawn from the NIH-sponsored Lung Tissue Research Consortium (LTRC). Demographic and pulmonary physiology data along with MMRC, SF-12, and SGRQ scores from women vs. men were compared with two-sample t-tests. Multivariate linear regression was used to examine the association between SF-12 component scores and gender while adjusting for other relevant variables.

RESULTS

The study sample consisted of 147 men and 74 women. Among several baseline variables, only DL(CO)% predicted differed between women and men, (43.7 vs. 38.0, p=0.03). In general, men exhibited lower (better) MMRC scores (1.7 vs. 2.4, p=0.02), particularly those with milder disease as measured by DL(CO)% predicted. In an adjusted analysis, SF-12 PCS scores in men were lower (worse) than women (p=0.01), an effect that was more pronounced in men with greater dyspnea scores. In a similar analysis, SF-12 MCS scores in women were lower than men (worse) (48.3 vs. 54.4, p=0.0004), an effect that was more pronounced in women with greater dyspnea scores.

CONCLUSIONS

Significant gender differences in HRQL exist in IPF. As compared to women, men reported less severe dyspnea, had worse SF-12 PCS scores, but better SF-12 MCS scores. Dyspnea appears to have a greater impact on the physical HRQL of men and the emotional HRQL of women. An improved understanding of the mechanism behind these differences is needed to better target interventions.

Systemic inflammation in chronic obstructive pulmonary disease: may adipose tissue play a role? Review of the literature and future perspectives

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide. Low-grade systemic inflammation is considered a hallmark of COPD that potentially links COPD to increased rate of systemic manifestations of the disease. Obesity with/without the metabolic syndrome and cachexia represent two poles of metabolic abnormalities that may relate to systemic inflammation. On one hand systemic inflammatory syndrome likely reflects inflammation in the lungs, i.e. results from lung-to plasma spillover of inflammatory mediators. On the other hand, obesity-related hypoxia results in local inflammatory response within adipose tissue per se, and may contribute to elevations in circulatory mediators by spillover from the adipose tissue to the systemic compartment. The extent to which systemic hypoxia contributes to the adipose tissue inflammation remains unknown. We assume that in patients with COPD and concurrent obesity at least three factors play a role in the systemic inflammatory syndrome: the severity of pulmonary impairment, the degree of obesity-related adipose tissue hypoxia, and the severity of systemic hypoxia due to reduced pulmonary functions. The present review summarizes the epidemiological and clinical evidence linking COPD to obesity, the role of adipose tissue as an endocrine organ, and the role of hypoxia in adipose tissue inflammation.

Body mass index and chronic obstructive pulmonary disease-related mortality: a nationally representative prospective study of 220,000 men in China

BACKGROUND

Low body mass index (BMI) is associated with chronic obstructive pulmonary disease (COPD) in populations where many are overweight. Substantial uncertainty remains about the relationship in populations with lower mean BMI levels, and about the relevance to it of the effects of smoking or of reverse causality.

METHODS

A nationally representative prospective cohort study included 221,194 Chinese men aged 40-79 years in 1990-91, who were followed up for 15 years or to the age of 80 years. Hazard ratios for COPD-related mortality vs baseline BMI were adjusted for age, smoking, drinking and other factors. To reduce reverse causality, main analyses excluded all men with prior history of any respiratory diseases or abnormal lung function at baseline, leaving 2960 COPD-related deaths (16% of all deaths).

RESULTS

The mean baseline BMI was 21.7 kg/m(2). There was a highly significant inverse association between BMI and COPD-related mortality among men without any apparent impairment of lung function. Approximately 90% of men had a baseline BMI <25 kg/m(2), and among them, 5 kg/m(2) lower BMI was associated with 31% (95% confidence interval 18-45%) higher COPD-related mortality. The excess risk persisted after restricting the analysis to never-smokers or excluding the first 5 years of follow-up.

CONCLUSIONS

Low BMI is associated with increased COPD mortality in a relatively lean adult male population in China where COPD is one of the most common causes of death.