Five comorbidities reflected the health status in patients with chronic obstructive pulmonary disease: the newly developed COMCOLD index

Mechanisms of osteoporosis associated with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a disease characterized by chronic respiratory symptoms due to inflammatory and destructive changes of the lung leading to progressive airflow obstruction. Fragility fractures associated with osteoporosis are among major comorbidities and have significant impacts on quality of life and prognosis of patients with COPD. Evidence suggests that both decreased bone mineral density (BMD) and impaired bone quality contribute to bone fragility and resultant fractures in COPD. Although various clinical risk factors of osteoporosis have been described, mechanisms of COPD-associated osteoporosis are still largely unknown. In addition, its specific treatment has not been established, either. Previous studies have suggested involvement of low BMI and sarcopenia in the pathogenesis of COPD-associated osteoporosis. In this narrative review, we will propose critical roles of vitamin D deficiency and inflammation, both of which are often present in COPD and may underlie the development of osteosarcopenia and impaired bone quality, ultimately causing fractures in COPD patients.

Systematic Review and Meta-Analysis of Psychological Distress and Acute Exacerbation of Chronic Obstructive Pulmonary Disease and Consequences

BACKGROUND

People with chronic obstructive pulmonary disease (COPD) occasionally develop acute exacerbation of COPD-a potentially fatal condition. Psychological distress was associated with acute exacerbation of COPD. However, the evidence on the effect of psychological distress on acute exacerbation of COPD remains unclear.

OBJECTIVE

The aim of this study was to explore the influence of psychological distress on acute exacerbation of COPD and its consequences.

METHODS

The current review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using three databases (PubMed, CINAHL, and PsyINFO) that were searched to identify relevant articles. Pooled risk ratios and 95% confidential interval were calculated from the included studies' data with random-effect methods to estimate the effect of psychological distress on acute exacerbation of COPD and its consequences.

RESULTS

Nineteen articles were included in the review. Most revealed that psychological distress was significantly associated with increased risk of acute exacerbation of COPD and its consequences. The meta-analyses showed that psychological distress increased risk of acute exacerbation of COPD, COPD-related hospitalization, and death.

CONCLUSION

Psychological distress had negative effects on acute exacerbation of COPD and its consequences. The results of the meta-analyses show that persons with COPD and psychological distress had a greater risk of acute exacerbation of COPD, hospitalization, and death.

Exploring the shared gene signatures of smoking-related osteoporosis and chronic obstructive pulmonary disease using machine learning algorithms

Objectives: Cigarette smoking has been recognized as a predisposing factor for both osteoporosis (OP) and chronic obstructive pulmonary disease (COPD). This study aimed to investigate the shared gene signatures affected by cigarette smoking in OP and COPD through gene expression profiling. Materials and methods: Microarray datasets (GSE11784, GSE13850, GSE10006, and GSE103174) were obtained from Gene Expression Omnibus (GEO) and analyzed for differentially expressed genes (DEGs) and weighted gene co-expression network analysis (WGCNA). Least absolute shrinkage and selection operator (LASSO) regression method and a random forest (RF) machine learning algorithm were used to identify candidate biomarkers. The diagnostic value of the method was assessed using logistic regression and receiver operating characteristic (ROC) curve analysis. Finally, immune cell infiltration was analyzed to identify dysregulated immune cells in cigarette smoking-induced COPD. Results: In the smoking-related OP and COPD datasets, 2858 and 280 DEGs were identified, respectively. WGCNA revealed 982 genes strongly correlated with smoking-related OP, of which 32 overlapped with the hub genes of COPD. Gene Ontology (GO) enrichment analysis showed that the overlapping genes were enriched in the immune system category. Using LASSO regression and RF machine learning, six candidate genes were identified, and a logistic regression model was constructed, which had high diagnostic values for both the training set and external validation datasets. The area under the curves (AUCs) were 0.83 and 0.99, respectively. Immune cell infiltration analysis revealed dysregulation in several immune cells, and six immune-associated genes were identified for smoking-related OP and COPD, namely, mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1), tissue-type plasminogen activator (PLAT), sodium channel 1 subunit alpha (SCNN1A), sine oculis homeobox 3 (SIX3), sperm-associated antigen 9 (SPAG9), and vacuolar protein sorting 35 (VPS35). Conclusion: The findings suggest that immune cell infiltration profiles play a significant role in the shared pathogenesis of smoking-related OP and COPD. The results could provide valuable insights for developing novel therapeutic strategies for managing these disorders, as well as shedding light on their pathogenesis.

Chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity, mortality, and health-care use worldwide. COPD is caused by exposure to inhaled noxious particles, notably tobacco smoke and pollutants. However, the broad range of factors that increase the risk of development and progression of COPD throughout the life course are increasingly being recognised. Innovations in omics and imaging techniques have provided greater insight into disease pathobiology, which might result in advances in COPD prevention, diagnosis, and treatment. Although few novel treatments have been approved for COPD in the past 5 years, advances have been made in targeting existing therapies to specific subpopulations using new biomarker-based strategies. Additionally, COVID-19 has undeniably affected individuals with COPD, who are not only at higher risk for severe disease manifestations than healthy individuals but also negatively affected by interruptions in health-care delivery and social isolation. This Seminar reviews COPD with an emphasis on recent advances in epidemiology, pathophysiology, imaging, diagnosis, and treatment.

Assessment of risk factors responsible for rapid deterioration of lung function over a period of one year in patients with chronic obstructive pulmonary disease

Compromised lung function is a common feature of COPD patients, but certain factors increase the rate of lung function decline in COPD patients. The objective of the current study was to investigate the effect of different clinically important factors responsible for rapid deterioration of lung function quantified as ≥ 60 ml decline in FEV1 over a period of one year. COPD patients recruited from the chest clinic of Penang hospital were followed-up for one year from August 2018 to August 2019. Rapid deterioration of lung function was defined as greater than 60 ml/year decline in force expiratory volume in one second. Among 367 included patients 73.84% were male, with mean age 65.26 (9.6) years and % predicted FEV1 51.07 (11.84). 30.27% patients showed mean decline of ≥ 60 ml in FEV1. The regression analysis showed that current smoking relative risk (RR) = 2.38 (1.78-3.07), p < 0.001); GOLD Stage III& IV RR = 1.43 (1.27-1.97), p < 0.001); mMRC score 3 to 4 RR = 2.03 (1.74-2.70), p < 0.01); SGRQ-C score ≥ 10 points difference RR = 2.01 (1.58-2.73), p < 0.01); SGRQ-C symptoms Score ≥ 10 points difference RR = 1.48 (1.23-2.29), p < 0.001); 6MWT < 350 m RR = 2.29 (1.87-3.34), p < 0.01); ≥ 3 exacerbation in study year RR = 2.28 (1.58-2.42, p < 0.001); 8 or more hospital admission days (RR = 3.62 (2.66-4.20), p < 0.001); Charlson comorbidity index ≥ 3 RR = 3.18 (2.23-3.76), p < 0.01) and emphysema RR = 1.31 (1.15-1.79), p < 0.01) were significant risk factors for the rapid deterioration of lung function (FEV1 decline ≥ 60 ml). Among different factors CCI score ≥ 3, abrupt decline in health status, exacerbation frequency ≥ 3, hospital admission days ≥ 8 and emphysema were reported as risk factors for rapid deterioration of lung function.

Predicting Future Health Risk in COPD: Differential Impact of Disease-Specific and Multi-Morbidity-Based Risk Stratification

Objective

Multi-morbidity contributes to mortality and hospitalisation in COPD, but it is uncertain how this interacts with disease severity in risk prediction. We compared contributions of multi-morbidity and disease severity factors in modelling future health risk using UK primary care healthcare data.

Methods

Health records from 103,955 patients with COPD identified from the Clinical Practice Research Datalink were analysed. We compared area under the curve (AUC) statistics for logistic regression (LR) models incorporating disease indices with models incorporating categorised comorbidities. We also compared these models with performance of The John Hopkins Adjusted Clinical Groups^® System (ACG) risk prediction algorithm.

Results

LR models predicting all-cause mortality outperformed models predicting hospitalisation. Mortality was best predicted by disease severity (AUC & 95% CI: 0.816 (0.805–0.827)) and prediction was enhanced only marginally by the addition of multi-morbidity indices (AUC & 95% CI: 0.829 (0.818–0.839)). The model combining disease severity and multi-morbidity indices was a better predictor of hospitalisation (AUC & 95% CI: 0.679 (0.672–0.686)). ACG-derived LR models outperformed conventional regression models for hospitalisation (AUC & 95% CI: 0.697 (0.690–0.704)) but not for mortality (AUC & 95% CI: 0.816 (0.805–0.827)).

Conclusion

Stratification of future health risk in COPD can be undertaken using clinical and demographic data recorded in primary care, but the impact of disease severity and multi-morbidity varies depending on the choice of health outcome. A more comprehensive risk modelling algorithm such as ACG offers enhanced prediction for hospitalisation by incorporating a wider range of coded diagnoses.

Exploring the impact of number and type of comorbidities on the risk of severe COPD exacerbations in Korean Population: a Nationwide Cohort Study

Background

It is difficult to assess the impact of multiple comorbidities on clinical outcomes in chronic obstructive pulmonary disease (COPD). In this study, we aimed to investigate exacerbation-associated comorbidities, determine whether the number of comorbidities is an independent risk factor for exacerbation, and identify other exacerbation-associated factors in a Korean COPD population using a nationwide population-based cohort. This study focused on severe exacerbations that required hospitalisation or emergency room visits.

Methods

The National Health Insurance Service-National Sample Cohort, version 2.0, data sampled between 2002 and 2015 were analysed. Data from two years after the diagnosis of COPD were analysed for each participant (N = 12,554, entire cohort). Moreover, 42% of the participants underwent additional health examinations (N = 5306, health-screening cohort). Fifteen comorbidities that were previously reported as risk factors for exacerbations were examined. A logistic regression model was used to analyse association with exacerbations.

Results

Asthma (1.57 [1.39–1.76] and 1.24 [1.06–1.44]), lung cancer (1.84 [1.30–2.59] and 2.28 [1.54–3.37]), and heart failure (1.39 [1.16–1.67] and 1.52 [1.18–1.97]) were associated with exacerbation in both cohorts (odds ratio [95% confidence interval] in the entire cohort and health-screening cohort, respectively). The number of comorbidities was an independent risk factor, and old age, male sex, low body mass index, and current smoking were also independent risk factors. High cholesterol levels and body mass index exerted protective effects against exacerbation.

Conclusions

The number of comorbidities, certain comorbidities such as asthma, lung cancer and heart failure, and low BMI were associated with an increased risk of severe exacerbation in COPD patients.

Improvement in Lung Function and Patient-Reported Outcomes in Patients with COPD with Comorbid Anxiety and Depression Receiving Nebulized Glycopyrrolate in the GOLDEN 3 and 4 Studies

Background

Anxiety and depression (A/D) are common in patients with chronic obstructive pulmonary disease (COPD) and are often associated with lower adherence to treatment and worse patient-related outcomes. However, studies on the impact of comorbid A/D on responses to bronchodilators are limited.

Methods

This post hoc analysis of pooled data (N=861) from the GOLDEN 3 and 4 studies compared the efficacy and safety of nebulized glycopyrrolate (GLY) 25 µg in patients with moderate-to-very-severe COPD, grouped by self-reported A/D. Changes in forced expiratory volume in 1 second (FEV₁) and health-related quality of life determined by St George’s Respiratory Questionnaire (SGRQ) scores in patients with or without comorbid A/D (A/D [+] or A/D [–]) were examined following 12 weeks of GLY 25 µg twice-daily (BID) or placebo treatment.

Results

A/D (+) patients were predominantly female, younger, included a higher proportion of current smokers, and had higher baseline SGRQ scores compared with the A/D (–) group. At 12 weeks, GLY resulted in placebo-adjusted improvements from baseline in FEV₁ of 46.9 mL (p=0.19; not significant) and 106.7 mL (p<0.0001), in the A/D (+) and A/D (–) groups, respectively. Improvements were observed with GLY compared to placebo in SGRQ scores, regardless of baseline A/D status; the placebo-adjusted least squares mean change from baseline in SGRQ total scores was –3.16 (p>0.05) and –3.34 (p<0.001), for the A/D (+) and A/D (–) groups, respectively. Despite numerical improvements in SGRQ scores with GLY in the A/D (+) group, a higher response to placebo was observed. GLY was generally well tolerated throughout 12 weeks of treatment; incidence of adverse events was higher in the A/D (+) group compared with the A/D (–) group in both treatment arms.

Conclusion

GLY 25 µg BID resulted in numerical improvements in FEV₁, SGRQ total scores and SGRQ responder rates in patients with moderate-to-very-severe COPD, regardless of A/D status at baseline; significant improvements were noted only in the A/D (+) group. The results emphasize the importance of considering underlying comorbidities including A/D when evaluating the efficacy of COPD treatments.

Fate or coincidence: do COPD and major depression share genetic risk factors?

Major depressive disorder (MDD) is a common comorbidity in chronic obstructive pulmonary disease (COPD), affecting up to 57% of patients with COPD. Although the comorbidity of COPD and MDD is well established, the causal relationship between these two diseases is unclear. A large-scale electronic health record clinical biobank and genome-wide association study summary statistics for MDD and lung function traits were used to investigate potential shared underlying genetic susceptibility between COPD and MDD. Linkage disequilibrium score regression was used to estimate genetic correlation between phenotypes. Polygenic risk scores (PRS) for MDD and lung function traits were developed and used to perform a phenome-wide association study (PheWAS). Multi-trait-based conditional and joint analysis identified single-nucleotide polymorphisms (SNPs) influencing both lung function and MDD. We found genetic correlations between MDD and all lung function traits were small and not statistically significant. A PRS-MDD was significantly associated with an increased risk of COPD in a PheWAS [odds ratio (OR) = 1.12, 95% confidence interval (CI): 1.09-1.16] when adjusting for age, sex and genetic ancestry, but this relationship became attenuated when controlling for smoking history (OR = 1.08, 95% CI: 1.04-1.13). No significant associations were found between the lung function PRS and MDD. Multi-trait-based conditional and joint analysis identified three SNPs that may contribute to both traits, two of which were previously associated with mood disorders and COPD. Our findings suggest that the observed relationship between COPD and MDD may not be driven by a strong shared genetic architecture.

Effect of multiple comorbidities on mortality in chronic obstructive pulmonary disease among Korean population: a nationwide cohort study

Background

The effects of comorbidities on chronic obstructive pulmonary disease (COPD) have been usually studied individually in the past. In this study, we aimed to investigate the comorbidities associated with mortality, the effect of multimorbidity on mortality and other factors associated with mortality among Korean COPD population.

Methods

The Korean National Health Insurance Service-National Sample Cohort version 2.0, collected between 2002 and 2015, was used. Among COPD patients [entire cohort (EC), N = 12,779], 44% of the participants underwent additional health examination, and they were analysed separately [health-screening cohort (HSC), N = 5624]. Fifteen comorbidities previously reported as risk factors for mortality were studied using Cox proportional hazards regression models.

Results

Total mortality rates were 38.6 per 1000 person-years (95% CI 37.32–40.01) and 27.4 per 1000 person-years (95% CI 25.68–29.22) in EC and HSC, respectively. The most common causes of death were disease progression, lung cancer, and pneumonia. Only some of the comorbidities had a direct impact on mortality. Multimorbidity, assessed by the number of comorbid diseases, was an independent risk factor of all-cause mortality in both cohorts and was a risk factor of respiratory mortality only in HSC. The Kaplan–Meier analysis showed significant differences in survival trajectories according to the number of comorbidities in all-cause mortality but not in respiratory mortality. Low BMI, old age and male sex were independent risk factors for both mortalities in both cohorts.

Conclusions

The number of comorbidities might be an independent risk factor of COPD mortality. Multimorbidity contributes to all-cause mortality in COPD, but the effect of multimorbidity is less evident on respiratory mortality.

Impact of tobacco-related chronic obstructive pulmonary disease on developmental trajectories of comorbidities in the Taiwan population

Comorbidities adversely affect the quality of life and survival of patients with chronic obstructive pulmonary disease (COPD), and timely identification and management of comorbidities are important in caring for COPD patients. This study aimed to investigate the impact of COPD on long-term developmental trajectories of its comorbidities. From 2010 to 2013, all spirometry-confirmed COPD patients with a 5-year follow-up period were identified as the cases. The prevalence of comorbidities and their trajectories in COPD cases were obtained and compared with those in non-COPD controls matched for age, sex, smoking status and Charlson comorbidity index (CCI). Over the study period, a total of 682 patients, 341 each in COPD and control groups were included, with a mean age of 69.1 years and 89% male. The baseline mean CCI was 1.9 for both groups of patients and significantly increased to 3.4 and 2.7 in COPD and control groups after 5 years, respectively (both P < 0.001). Through the 5-year follow-up, a significant increase in the prevalence of all comorbidities of interest was observed in the COPD cohort and the incidence was remarkably higher for hypertension [incidence rate ratio (IRR) 1.495; 95% confidence interval (CI) 1.017–2.198], malignancy (IRR 2.397; 95% CI 1.408–4.081), diabetes mellitus (IRR 2.927; 95% CI 1.612–5.318), heart failure (IRR 2.531; 95% CI 1.502–4.265) and peptic ulcer disease (IRR 2.073; 95% CI 1.176–3.654) as compared to the non-COPD matched controls. In conclusion, our findings suggest that the presence of COPD may be considered a pathogenic factor involved in the development of certain comorbidities.

Using the BODE Index and Comorbidities to Predict Health Utilization Resources in Chronic Obstructive Pulmonary Disease

Background and Objective

Chronic Obstructive Pulmonary Disease (COPD) is a common chronic respiratory disease that in the long term may develop into respiratory failure or even cause death and may coexist with other diseases. Over time, it may incur huge medical expenses, resulting in a heavy socio-economy burden. The BODE (Body mass index, airflow Obstruction, Dyspnea, and Exercise capacity) index is a predictor of the number and severity of acute exacerbations of COPD. This study focused on the correlation between the BODE index, comorbidity, and healthcare resource utilization in COPD.

Patients and Methods

This is a retrospective study of clinical outcomes of COPD patients with complete BODE index data in our hospital from January 2015 to December 2016. Based on the patients’ medical records in our hospital’s electronic database from January 1, 2015 to August 31, 2017, we analyzed the correlation between BODE index, Charlson comorbidity index (CCI), and medical resources.

Results

Of the 396 patients with COPD who met the inclusion criteria, 382 (96.5%) were male, with an average age of 71.3 ± 8.4 years. Healthcare resource utilization was positively correlated with the BODE index during the 32 months of retrospective clinical outcomes. The study found a significant association between the BODE index and the CCI of COPD patients (p < 0.001). In-hospitalization expenses were positively correlated with CCI (p < 0.001). Under the same CCI, the higher the quartile, the higher the hospitalization expenses. BODE quartiles were positively correlated with number of hospitalizations (p < 0.001), hospitalization days (p < 0.001), hospitalization expenses (p = 0.005), and total medical expenses (p = 0.024).

Conclusion

This study demonstrates the value of examining the BODE index and comorbidities that can predict healthcare resource utilization in COPD.

A Nomogram for Predicting Severe Exacerbations in Stable COPD Patients

Objective

To develop a practicable nomogram aimed at predicting the risk of severe exacerbations in COPD patients at three and five years.

Methods

COPD patients with prospective follow-up data were extracted from Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS) obtained from National Heart, Lung and Blood Institute (NHLBI) Biologic Specimen and Data Repository Information Coordinating Center. We comprehensively considered the demographic characteristics, clinical data and inflammation marker of disease severity. Cox proportional hazard regression was performed to identify the best combination of predictors on the basis of the smallest Akaike Information Criterion. A nomogram was developed and evaluated on discrimination, calibration, and clinical efficacy by the concordance index (C-index), calibration plot and decision curve analysis, respectively. Internal validation of the nomogram was assessed by the calibration plot with 1000 bootstrapped resamples.

Results

Among 1711 COPD patients, 523 (30.6%) suffered from at least one severe exacerbation during follow-up. After stepwise regression analysis, six variables were determined including BMI, severe exacerbations in the prior year, comorbidity index, post-bronchodilator FEV₁% predicted, and white blood cells. Nomogram to estimate patients' likelihood of severe exacerbations at three and five years was established. The C-index of the nomogram was 0.74 (95%CI: 0.71-0.76), outperforming ADO, BODE and DOSE risk score. Besides, the calibration plot of three and five years showed great agreement between nomogram predicted possibility and actual risk. Decision curve analysis indicated that implementation of the nomogram in clinical practice would be beneficial and better than aforementioned risk scores.

Conclusion

Our new nomogram was a useful tool to assess the probability of severe exacerbations at three and five years for COPD patients and could facilitate clinicians in stratifying patients and providing optimal therapies.

Demographic, Clinical and Management Characteristics of Newly Diagnosed COPD Patients in Turkey: A Real-Life Study

Purpose

In order to determine the clinical and sociodemographic characteristics of newly diagnosed treatment-naïve asthma and COPD patients in Turkey, a multicenter study in 2012 was initiated . We aimed to investigate the characteristics and therapies of COPD patients in the original study in more detail.

Patients and Methods

This nation-wide, multicentric, non-interventional, prospective, real-life observational cohort study was conducted in 122 centers. The newly diagnosed patients were not receiving any treatment before the recruitment. Their general characteristics, the combined GOLD 2011 COPD categories and exacerbation histories were noted. The patients were followed up with 3 voluntary visits for 1 year. Their adherence to the inhaled treatment according to GOLD 2011 was evaluated during follow-up visits.

Results

The study included 776 COPD patients. Their mean age was 59.4±9.1 years, and 11.9% of the patients were female. 35.1% of the patients were in the GOLD 2011 C and D category. 12.6% are frequent exacerbators, and 52.8% had at least one comorbid condition. 71.8% overtreatment rate was detected. Their attendance rates for three follow-up visits became 55.9%, 32.9% and 18.7%, respectively. The adherence rate to the treatment was measured as 81.9%.

Conclusion

Although these patients were diagnosed for the first time, the GOLD C and D categories and frequent exacerbator phenotype were found at a high rate. They were usually prescribed an overtreatment regimen. We think that newly diagnosed COPD patients should be evaluated carefully, and best effort should be made to treat these patients in accordance with the recommendations of the major COPD guidelines.

Racial-ethnic disparities in self-reported health status among US adults adjusted for sociodemographics and multimorbidities, National Health and Nutrition Examination Survey 2011-2014

Objective: To investigate racial-ethnic disparities in self-reported health status adjusting for sociodemographic factors and multimorbidities.Design: A total of 9499 adult participants aged 20 years and older from the United States (US); reported by the National Health and Nutrition Examination Survey (NHANES), a cross-sectional survey - for years 2011-2014. The main outcome measure was self-reported health status categorized as excellent/very good, good (moderate), and fair/poor.Results: Of the NHANES participants, 40.7% reported excellent/very good health, 37.2% moderate health and 22.1% fair/poor health. There were 42.8% who were non-Hispanic whites, 20.2% were Hispanic, 23.8% were non-Hispanic blacks, and 13.2% were non-Hispanic Asians. Compared to non-Hispanic whites, Hispanics [Odds Ratio (OR) = 2.91, 95% Confidence Interval (CI) = 2.28-3.71] and non-Hispanic blacks [OR = 1.51, 95% CI = 1.26-1.83] were more likely to report fair/poor health, whereas, non-Hispanic Asians [OR = 1.42, 95% CI = 1.14-1.76] were more likely to report moderate health than excellent/very good health. Compared to those with no chronic conditions, participants with two or three chronic conditions [OR = 9.35, 95% CI = 7.26-12.00] and with four or more chronic conditions [OR = 38.10, 95% CI = 26.50-54.90] were more likely to report fair/poor health than excellent/very good health status.Conclusion: The racial-ethnic differences in self-reported health persisted even after adjusting for sociodemographics and number of multimorbidities. The findings highlight the potential importance of self-reported health status and the need to increase health awareness through health assessment and health-promotional programs among the vulnerable minority US adults.

Development of comorbidity score for patients undergoing major surgery

OBJECTIVE

To develop and validate a claims-based comorbidity score for patients undergoing major surgery, and compare its performance with established comorbidity scores.

DATA SOURCE

Five percent Medicare data from 2007 to 2014.

STUDY DESIGN

Retrospective cohort study of patients aged ≥65 years undergoing six major operations (N = 99 250).

DATA COLLECTION

One-year mortality was the primary outcome. Secondary outcomes were hospital mortality, 30-day mortality, 30-day readmission, and length of stay. The comorbidity score was developed in the derivation cohort (70 percent sample) using logistic regression model. The comorbidity score was calibrated and validated in the validation cohort (30 percent sample), and compared against the Charlson, Elixhauser, and Centers for Medicare and Medicaid Services Hierarchical Condition Categories (CMS-HCC) comorbidity scores using c-statistic, net reclassification improvement, and integrated discrimination improvement.

PRINCIPAL FINDINGS

In the validation cohort, the surgery-specific comorbidity score was well calibrated and performed better than the Charlson, Elixhauser, and CMS-HCC comorbidity scores for all outcomes; the performance was comparable to the CMS-HCC for 30-day readmission. For example, the surgery-specific comorbidity score (c-statistic = 0.792; 95% CI, 0.785-0.799) had greater discrimination than the Charlson (c-statistic = 0.747; 95% CI, 0.739-0.755), Elixhauser (c-statistic = 0.747; 95% CI, 0.735-0.755), or CMS-HCC (c-statistic = 0.755; 95% CI, 0.747-0.763) scores in predicting 1-year mortality. The net reclassification improvement and integrated discrimination improvement were greater for surgery-specific comorbidity score compared to the Charlson, Elixhauser, and CMS-HCC scores.

CONCLUSIONS

Compared to commonly used comorbidity measures, a surgery-specific comorbidity score better predicted outcomes in the surgical population.

Loss of skin elasticity is associated with pulmonary emphysema, biomarkers of inflammation, and matrix metalloproteinase activity in smokers

BACKGROUND

Elastin breakdown and the resultant loss of lung elastic recoil is a hallmark of pulmonary emphysema in susceptible individuals as a consequence of tobacco smoke exposure. Systemic alterations to the synthesis and degradation of elastin may be important to our understanding of disease phenotypes in chronic obstructive pulmonary disease. We investigated the association of skin elasticity with pulmonary emphysema, obstructive lung disease, and blood biomarkers of inflammation and tissue protease activity in tobacco-exposed individuals.

METHODS

Two hundred and thirty-six Caucasian individuals were recruited into a sub-study of the University of Pittsburgh Specialized Center for Clinically Orientated Research in chronic obstructive pulmonary disease, a prospective cohort study of current and former smokers. The skin viscoelastic modulus (VE), a determinant of skin elasticity, was recorded from the volar forearm and facial wrinkling severity was determined using the Daniell scoring system.

RESULTS

In a multiple regression analysis, reduced VE was significantly associated with cross-sectional measurement of airflow obstruction (FEV1/FVC) and emphysema quantified from computed tomography (CT) images, β = 0.26, p = 0.001 and β = 0.24, p = 0.001 respectively. In emphysema-susceptible individuals, elasticity-determined skin age was increased (median 4.6 years) compared to the chronological age of subjects without emphysema. Plasma biomarkers of inflammation (TNFR1, TNFR2, CRP, PTX3, and SAA) and matrix metalloproteinase activity (MMP1, TIMP1, TIMP2, and TIMP4) were inversely associated with skin elasticity.

CONCLUSIONS

We report that an objective non-invasive determinant of skin elasticity is independently associated with measures of lung function, pulmonary emphysema, and biomarkers of inflammation and tissue proteolysis in tobacco-exposed individuals. Loss of skin elasticity is a novel observation that may link the common pathological processes that drive tissue elastolysis in the extracellular matrix of the skin and lung in emphysema-susceptible individuals.

[The GLORI-COPD score: detection of COPD patients at risk of complications]

DEVELOPMENT OF THE GLORI-COPD SCORE

GLObal RIsk of severe outcomes in COPD patients.

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is a commonly under-diagnosed disease. This study aimed to develop a screening tool for COPD patients with a high risk of complications, taking into account COPD severity and associated co-morbidity.

METHODS

Two Delphi rounds were conducted to select the items for a preliminary score. Subsequently, this score was submitted to patients with a possible diagnosis of COPD attending for pulmonary function tests in hospital and primary care. Items associated with a diagnosis of COPD and its severity were examined with multivariate logistic regressions. Associated items in our analyses and in the literature were integrated into the score. The score was developed with a factorial analysis and optimized according to ROC curves.

RESULTS

Fifteen items were selected with the Delphi method, of which six were retained after logistic regression. They were submitted to 64 patients (mean age: 59+/-13.6 years). Factors associated with COPD were smoking ≥10 pack-years and a history of acute exacerbations. Low levels of activity and coughing up sputum were associated with COPD severity. Age ≥40 years and co-morbidities were added to the score. According to the factorial analysis, a two-stage score was developed assessing first the diagnosis of COPD and then the risk of severe outcomes. It showed a sensitivity of 71 %, a specificity of 77 %. The positive and negative predictive value were respectively 28 % and 96 %.

CONCLUSION

The score was an acceptable screening tool to identify COPD patients with high risk of complications. Nevertheless, validation needs be performed in a larger population to allow its use in primary care.

Influence of comorbidities in long-term survival of chronic obstructive pulmonary disease patients

Background

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of mortality and morbidity around the world, with comorbidities in COPD being common and having a negative effect on survival. We investigate the effects of comorbidities on long-term survival of COPD patients.

Methods

The study included patients with COPD who were hospitalized with an exacerbation. The demographic characteristics, hematological and biochemical parameters, pulmonary function test parameters and comorbidities of the patients were obtained from the hospital database and patient records, and the mortality of the patients was assessed at two years. The parameters considered to be related to mortality were analyzed using the Cox regression method.

Results

A total of 826 patients with COPD were included in the study, and the rate of patients with at least one comorbidity was 84.5%. The most common comorbidities were hypertension (n=394, 47.7%), heart failure (n=244, 29.5%) and DM (n=173, 20.9%). In a Cox regression analysis, the Charlson Comorbidity Index was strongly associated with mortality (P=0.000). In Kaplan-Meier analysis, a significant association was noted between the increasing number of comorbidities and long-term mortality, when compared to the patients without comorbidity (comorbidity numbers 1, 2 and ≥3; HR: 1.37, P=0.032, HR: 1.40, P=0.028 and HR: 1.65, P=0.000, respectively).

Conclusions

Increasing number of comorbidities in COPD patients with severe exacerbation were found to negatively affect long-term survival. We consider both the evaluation and treatment of comorbidities to be important in the reduction of long-term mortality in patients with COPD.

COPD classification models and mortality prediction capacity

Objective

Our aim was to assess the impact of comorbidities on existing COPD prognosis scores.

Patients and methods

A total of 543 patients with COPD (FEV₁ <80% and FEV₁/FVC <70%) were included between January 2003 and January 2004. Patients were stable for at least 6 weeks before inclusion and were followed for 5 years without any intervention by the research team. Comorbidities and causes of death were established from medical reports or information from primary care medical records. The GOLD system and the body mass index, obstruction, dyspnea and exercise (BODE) index were used for COPD classification. Patients were also classified into four clusters depending on the respiratory disease and comorbidities. Cluster analysis was performed by combining multiple correspondence analyses and automatic classification. Receiver operating characteristic curves and the area under the curve (AUC) were calculated for each model, and the DeLong test was used to evaluate differences between AUCs. Improvement in prediction ability was analyzed by the DeLong test, category-free net reclassification improvement and the integrated discrimination index.

Results

Among the 543 patients enrolled, 521 (96%) were male, with a mean age of 68 years, mean body mass index 28.3 and mean FEV₁% 55%. A total of 167 patients died during the study follow-up. Comorbidities were prevalent in our cohort, with a mean Charlson index of 2.4. The most prevalent comorbidities were hypertension, diabetes mellitus and cardiovascular diseases. On comparing the BODE index, GOLD_ABCD, GOLD₂₀₁₇ and cluster analysis for predicting mortality, cluster system was found to be superior compared with GOLD₂₀₁₇ (0.654 vs 0.722, P=0.006), without significant differences between other classification models. When cardiovascular comorbidities and chronic renal failure were added to the existing scores, their prognostic capacity was statistically superior (P<0.001).

Conclusion

Comorbidities should be taken into account in COPD management scores due to their prevalence and impact on mortality.

Comparing comorbidity measures and fatigue post myocardial infarction

PURPOSE/AIMS

The purpose of this study was to examine comorbidity measures that may relate to the symptom of fatigue post MI: self-reported comorbidities, medication-validated comorbidities, weighted comorbidities for fatigue, and number of comorbidities.

DESIGN

Using a cross sectional design, we interviewed a convenience sample of 98 adults, 65 and older, who were 6 to 8 months post myocardial infarction.

METHODS

Participants self-reported their comorbidities using a list of 23 comorbid conditions. All medications were visually inspected, and medications were reviewed by a geriatric pharmacist for a common side effect of fatigue. The Revised Piper Fatigue Scale was used to measure fatigue.

RESULTS

The mean age of the participants was 76 (SD = 6.3), and most of the sample were White (84%). Neither medication-validated comorbidities nor those medications with fatigue as a common side effect explained fatigue. When controlling for age, sex, and marital status, self-reported comorbidities explained 10% of the variance in fatigue (F (4, 93) = 2.65; p = 0.04). Having 5 or more self-reported comorbidities explained 7% of variance in fatigue scores (F (1, 96) = 7.53; p = 0.007).

CONCLUSION

Comorbidities are associated with fatigue post MI. Adults post MI with 5 or more comorbidities should be screened for fatigue.

[Spotting the GLObalRIsk of severe outcomes in undiagnosed COPD patients (GLORI-COPD)]

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a severe chronic disease and its prevalence is increasing. Nevertheless, mortality linked to moderate and mild COPD without comorbidities is low. The aim of the study is to create and validate a questionnaire in primary care to spot patients with undiagnosed COPD who are at high risk of severe complications considering the severity of their COPD and their comorbidities.

METHODS

The development of the questionnaire has three steps. The first is the selection of the items which can be included in the questionnaire with a two-round Delphi method. The second step is a cross-sectional study to assess the link between spirometry and the selected items in the first step. The last step is the validation of the questionnaire in a prospective study in primary care.

EXPECTED RESULTS

Identifying undiagnosed COPD patients with a high global risk of complications in primary care will help to establish which patients have to be diagnosed as a priority. This is particularly useful in general practice as the patient is considered globally and not just on the basis of respiratory criteria. It should allow better selection of patients who need specialised follow up.

Peripheral Artery Disease and Its Clinical Relevance in Patients with Chronic Obstructive Pulmonary Disease in the COPD and Systemic Consequences-Comorbidities Network Study

RATIONALE

Knowledge about the prevalence of objectively assessed peripheral artery disease (PAD) and its clinical relevance in patients with chronic obstructive pulmonary disease (COPD) is scarce.

OBJECTIVES

We aimed to: (1) assess the prevalence of PAD in COPD compared with distinct control groups; and (2) study the association between PAD and functional capacity as well as health status.

METHODS

The ankle-brachial index was used to diagnose PAD (ankle-brachial index ≤ 0.9). The 6-minute-walk distance, health status (St. George's Respiratory Questionnaire), COPD Assessment Test, and EuroQol-5-Dimensions were assessed in patients enrolled in the German COPD and Systemic Consequences-Comorbidities Network cohort study. Control groups were derived from the Study of Health in Pomerania.

MEASUREMENTS AND MAIN RESULTS

A total of 2,088 patients with COPD (61.1% male; mean [SD] age, 65.3 [8.2] years, GOLD (Global Initiative for Chronic Obstructive Lung Disease) stages I-IV: 9.4, 42.5, 37.5, and 10.5%, respectively) were included, of which 184 patients (8.8%; GOLD stage I-IV: 5.1, 7.4, 11.1, and 9.5%, respectively, vs. 5.9% in patients with GOLD stage 0 in the COPD and Systemic Consequences-Comorbidities Network) had PAD. In the Study of Health in Pomerania, PAD ranged from 1.8 to 4.2%. Patients with COPD with PAD had a significantly shorter 6-minute-walk distance (356 [108] vs. 422 [103] m, P < 0.001) and worse health status (St. George's Respiratory Questionnaire: 49.7 [20.1] vs. 42.7 [20.0] points, P < 0.001; COPD Assessment Test: 19.6 [7.4] vs. 17.9 [7.4] points, P = 0.004; EuroQol-5-Dimensions visual analog scale: 51.2 [19.0] vs. 57.2 [19.6], P < 0.001). Differences remained significant after correction for several confounders.

CONCLUSIONS

In a large cohort of patients with COPD, 8.8% were diagnosed with PAD, which is higher than the prevalence in control subjects without COPD. PAD was associated with a clinically relevant reduction in functional capacity and health status.

Physical activity and risk of comorbidities in patients with chronic obstructive pulmonary disease: a cohort study

Multi-morbidity is common in patients with chronic obstructive pulmonary disease and low levels of physical activity are hypothesized to be an important risk factor. The current study aimed to assess the longitudinal association between physical activity and risk of seven categories of comorbidity in chronic obstructive pulmonary disease patients. The study included 409 patients from primary care practice in the Netherlands and Switzerland. We assessed physical activity using the Longitudinal Ageing Study Amsterdam Physical Activity Questionnaire at baseline and followed patients for up to 5 years. During follow-up, patients reported their comorbidities (cardiovascular, neurological, endocrine, musculoskeletal, malignant, and infectious diseases) and completed the Hospital Anxiety and Depression Scale questionnaire for mental health assessment. We implemented multinomial logistic regression (an approximation to discrete time survival model using death as a competing risk) for our analysis. Study results did not suggest a statistically significant association of baseline physical activity with the development of seven categories of comorbidity. However, when we focused on depression and anxiety symptoms, we found that higher levels of physical activity at baseline were associated with a lower risk for depression (adjusted hazard ratio, 0.85; 0.75–0.95; p = 0.005) and anxiety (adjusted hazard ratio, 0.89; 0.79–1.00; p = 0.045). In chronic obstructive pulmonary disease patients, those with high physical activity are less likely to develop depression or anxiety symptoms over time. Increasing physical activity in chronic obstructive pulmonary disease patients may be an approach for testing to lower the burden from incident depression and anxiety.

Patients with chronic lung disease who stay physically active could reduce their chances of depression and anxiety. Milo Puhan at the University of Zurich, Switzerland, and co-workers assessed the association between physical activity and the risk of developing various co-existing diseases in 409 patients with chronic obstructive pulmonary disease (COPD). Co-morbidities such as cardiovascular diseases, diabetes and depression are prevalent in patients with COPD, but the reasons why are not clear. Puhan’s team assessed patients’ activity levels using an existing questionnaire, and administered another questionnaire to assess mental health. They followed the cohort for 5 years. Results indicated weak associations between physical activity levels and most physical illnesses, but there were significant links between higher levels of physical activity and a reduced risk of depression and anxiety. The results could inform novel COPD treatment programs.

What patients with pulmonary fibrosis and their partners think: a live, educative survey in the Netherlands and Germany

Pulmonary fibrosis greatly impacts patients and their partners. Unmet needs of patients are increasingly acknowledged; the needs of partners often remain unnoticed. Little is known about the best way to educate patients and partners. We investigated pulmonary fibrosis patients' and partners' perspectives and preferences in care, and the differences in these between the Netherlands and Germany. Additionally, we evaluated whether interactive interviewing could be a novel education method in this population.

Patients and partners were interviewed during pulmonary fibrosis patient information meetings. In the Netherlands, voting boxes were used and results were projected directly. In Germany, questionnaires were used.

In the Netherlands, 278 patients and partners participated; in Germany, 51. Many participants experienced anxiety. Almost all experienced misunderstanding, because people do not know what pulmonary fibrosis is. All expressed a need for information, psychological support and care for partners. Use of the interactive voting system was found to be pleasant (70%) and informative (94%).

This study improves the knowledge of care needs of patients with pulmonary fibrosis and their partners. There were no major differences between the Netherlands and Germany. Interactive interviewing could be an attractive method to acquire insights into the needs and preferences of patients and partners, while providing them with information at the same time.

The needs of patients with pulmonary fibrosis and partners, and the value of interactive interviewinghttp://ow.ly/M02t307jdEh

End-of-life prognostic indicators in patients with COPD: part 2

In the UK, chronic respiratory diseases cause 13% of adult disability. The major chronic respiratory disease is chronic obstructive pulmonary disease (COPD), a condition involving chronic airway inflammation that causes airflow obstruction and destruction of lung tissue. This leads to a progressive loss of respiratory membrane, which accounts for the clinical manifestation of COPD, which is difficulty maintaining sufficient gas exchange to meet metabolic demands. The primary cause is smoking, with the vast majority of COPD patients having a past or present history of smoking. However, exposure to industrial pollutants is also a contributing factor, as is a rare genetic predisposition to developing COPD.

Associations between chronic comorbidity and exacerbation risk in primary care patients with COPD

BACKGROUND

COPD often coexists with chronic conditions that may influence disease prognosis. We investigated associations between chronic (co)morbidities and exacerbations in primary care COPD patients.

METHOD

Retrospective cohort study based on 2012-2013 electronic health records from 179 Dutch general practices. Comorbidities from patients with physician-diagnosed COPD were categorized according to International Classification of Primary Care (ICPC) codes. Chi-squared tests, uni- and multivariable logistic, and Cox regression analyses were used to study associations with exacerbations, defined as oral corticosteroid prescriptions.

RESULTS

Fourteen thousand six hundred three patients with COPD could be studied (mean age 67 (SD 12) years, 53% male) for two years. At baseline 12,826 (88%) suffered from ≥1 comorbidities, 3263 (22%) from ≥5. The most prevalent comorbidities were hypertension (35%), coronary heart disease (19%), and osteoarthritis (18%). Several comorbidities showed statistically significant associations with frequent (i.e., ≥2/year) exacerbations: heart failure (odds ratio [OR], 95% confidence interval: 1.72; 1.38-2.14), blindness & low vision (OR 1.46; 1.21-1.75), pulmonary cancer (OR 1.85; 1.28-2.67), depression 1.48; 1.14-1.91), prostate disorders (OR 1.50; 1.13-1.98), asthma (OR 1.36; 1.11-1.70), osteoporosis (OR 1.41; 1.11-1.80), diabetes (OR 0.80; 0.66-0.97), dyspepsia (OR 1.25; 1.03-1.50), and peripheral vascular disease (OR 1.20; 1.00-1.45). From all comorbidity categories, having another chronic respiratory disease beside COPD showed the highest risk for developing a new exacerbation (Cox hazard ratio 1.26; 1.17-1.36).

CONCLUSION

Chronic comorbidities are highly prevalent in primary care COPD patients. Several chronic comorbidities were associated with having frequent exacerbations and increased exacerbation risk.

The Role of Mitochondria and Oxidative/Antioxidative Imbalance in Pathobiology of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a common preventable and treatable disease, characterized by persistent airflow limitation that is usually progressive and associated with an enhanced chronic inflammatory response in the airways and the lung to noxious particles or gases. The major risk factor of COPD, which has been proven in many studies, is the exposure to cigarette smoke. However, it is 15-20% of all smokers who develop COPD. This is why we should recognize the pathobiology of COPD as involving a complex interaction between several factors, including genetic vulnerability. Oxidant-antioxidant imbalance is recognized as one of the significant factors in COPD pathogenesis. Numerous exogenous and endogenous sources of ROS are present in pathobiology of COPD. One of endogenous sources of ROS is mitochondria. Although leakage of electrons from electron transport chain and forming of ROS are the effect of physiological functioning of mitochondria, there are various intra- and extracellular factors which may increase this amount and significantly contribute to oxidative-antioxidative imbalance. With the coexistence with impaired antioxidant defence, all these issues lead to oxidative and carbonyl stress. Both of these states play a significant role in pathobiology of COPD and may account for development of major comorbidities of this disease.

External validation of multidimensional prognostic indices (ADO, BODEx and DOSE) in a primary care international cohort (PROEPOC/COPD cohort)

BACKGROUND

Due to the heterogeneous and systemic nature of the chronic obstructive pulmonary disease (COPD), the new guidelines are oriented toward individualized attention. Multidimensional scales could facilitate its proper clinical and prognostic assessment, but not all of them were validated in an international primary care cohort, different from the original ones used for model development. Therefore, our main aim is to assess the prognostic capacity of the ADO, BODEx and DOSE indices in primary care for predicting mortality in COPD patients and to validate the models obtained in subgroups of patients, classified by revised Global Initiative for Chronic Obstructive Lung Disease (2011) and updated Spanish Guideline (2014). Besides, we want to confirm that the prognostic capacity of all indices increases if the number of exacerbations is substituted by the interval between them and to assess the impact on health of the patient's lifestyle, social network and adherence to treatment.

METHODS

Design: External validation of scales, open and prospective cohort study in primary care.

SETTING

36 health centres in 6 European high, medium and low income countries.

SUBJECTS

477 patients diagnosed with COPD, captured in clinical visit by their General Practitioner/Nurse.

PREDICTORS

Detailed patient history, exacerbations, lung function test and questionnaires at baseline.

OUTCOMES

Exacerbations, all-cause mortality and specific mortality, within 5 years of recruitment.

ANALYSIS

Multivariate logistic regression and Cox regression will be used. Possible non-linear effect of the indices will be studied by using Structured Additive Regression models with penalised splines. Subsequently, we will assess different aspects of the regression models: discrimination, calibration and diagnostic precision. Clinical variables modulated in primary care and the interval between exacerbations will be considered and incorporated into the analysis.

DISCUSSION

The Research Agenda for General Practice/Family Medicine highlights that the evidence on predictive values of prognostic indices in primary care is scarce. A prospective cohort like that of PROEPOC/COPD provides good opportunities for research into COPD and make communication easier between family practitioners, nursing staff, pneumologists and other professionals, supporting a multi-disciplinary approach to the treatment of these patients.

TRIAL REGISTRATION

ISRCTN52402811 . Date: 15/01/2015. Prospectively registered.

Prevalence and burden of comorbidities in Chronic Obstructive Pulmonary Disease

The classical definition of Chronic Obstructive Pulmonary Disease (COPD) as a lung condition characterized by irreversible airway obstruction is outdated. The systemic involvement in patients with COPD, as well as the interactions between COPD and its comorbidities, justify the description of chronic systemic inflammatory syndrome. The pathogenesis of COPD is closely linked with aging, as well as with cardiovascular, endocrine, musculoskeletal, renal, and gastrointestinal pathologies, decreasing the quality of life of patients with COPD and, furthermore, complicating the management of the disease. The most frequently described comorbidities include skeletal muscle wasting, cachexia (loss of fat-free mass), lung cancer (small cell or non-small cell), pulmonary hypertension, ischemic heart disease, hyperlipidemia, congestive heart failure, normocytic anemia, diabetes, metabolic syndrome, osteoporosis, obstructive sleep apnea, depression, and arthritis. These complex interactions are based on chronic low-grade systemic inflammation, chronic hypoxia, and multiple common predisposing factors, and are currently under intense research. This review article is an overview of the comorbidities of COPD, as well as their interaction and influence on mutual disease progression, prognosis, and quality of life.

The Inaccuracy of Patient Recall for COPD Exacerbation Rate Estimation and Its Implications: Results from Central Adjudication

BACKGROUND

COPD exacerbation incidence rates are often ascertained retrospectively through patient recall and self-reports. We compared exacerbation ascertainment through patient self-reports and single-physician chart review to central adjudication by a committee and explored determinants and consequences of misclassification.

METHODS

Self-reported exacerbations (event-based definition) in 409 primary care patients with COPD participating in the International Collaborative Effort on Chronic Obstructive Lung Disease: Exacerbation Risk Index Cohorts (ICE COLD ERIC) cohort were ascertained every 6 months over 3 years. Exacerbations were adjudicated by single experienced physicians and an adjudication committee who had information from patient charts. We assessed the accuracy (sensitivities and specificities) of self-reports and single-physician chart review against a central adjudication committee (AC) (reference standard). We used multinomial logistic regression and bootstrap stability analyses to explore determinants of misclassifications.

RESULTS

The AC identified 648 exacerbations, corresponding to an incidence rate of 0.60 ± 0.83 exacerbations/patient-year and a cumulative incidence proportion of 58.9%. Patients self-reported 841 exacerbations (incidence rate, 0.75 ± 1.01; incidence proportion, 59.7%). The sensitivity and specificity of self-reports were 84% and 76%, respectively, those of single-physician chart review were between 89% and 96% and 87% and 99%, respectively. The multinomial regression model and bootstrap selection showed that having experienced more exacerbations was the only factor consistently associated with underreporting and overreporting of exacerbations (underreporters: relative risk ratio [RRR], 2.16; 95% CI, 1.76-2.65 and overreporters: RRR, 1.67; 95% CI, 1.39-2.00).

CONCLUSIONS

Patient 6-month recall of exacerbation events are inaccurate. This may lead to inaccurate estimates of incidence measures and underestimation of treatment effects. The use of multiple data sources combined with event adjudication could substantially reduce sample size requirements and possibly cost of studies.

CLINICAL TRIAL REGISTRATION

www.ClinicalTrials.gov, NCT00706602.

Osteoporosis Associated with Chronic Obstructive Pulmonary Disease

Recent epidemiological studies have revealed that osteoporosis is closely associated with common chronic diseases including diabetes, hypertension, chronic kidney disorders, and chronic obstructive pulmonary disease (COPD). COPD is a chronic inflammatory airway disease but now well known to be associated with various systemic comorbidities including osteoporosis. Osteoporosis and osteoporotic fractures are extremely common in COPD patients, which have significant impacts on their quality of life (QOL), activities of daily life (ADL), respiratory function, and possibly their prognosis. COPD-associated osteoporosis is however extremely under-recognized, hence undertreated. Recent studies have suggested that both decreased bone mineral density (BMD) and impaired bone quality compromise bone strength causing fractures in COPD. In COPD patients, various general clinical risk factors for osteoporosis are present including smoking, older age, low body weight, and physical inactivity. In addition, disease-related risk factors such as decreased pulmonary function, inflammation, glucocorticoid use and vitamin D deficiency/insufficiency have been linked to the development of osteoporosis in COPD. Increased awareness of osteoporosis in COPD, especially that of high prevalence of vertebral fractures is called upon among general physicians as well as pulmonologists. Routine screening for osteoporosis and risk assessment of fractures will enable physicians to diagnose COPD patients with comorbid osteoporosis at an early stage. Timely prevention of developing osteoporosis together with appropriate treatment of established osteoporosis may improve QOL and ADL of the COPD patients, preserve their lung function and eventually result in better prognosis in these patients.

Psychosocial consequences of living with breathlessness due to advanced disease

PURPOSE OF REVIEW

Breathlessness is one of the most important symptoms of patients with advanced life-limiting disease, such as chronic obstructive pulmonary disease, chronic heart failure, cancer, or pulmonary fibrosis. Breathlessness has major implications for patients as well as their family caregivers. The present review provides an overview of recent knowledge concerning the psychological and social consequences of breathlessness, including behavioural responses to breathlessness, and the impact of breathlessness on the family caregiver.

RECENT FINDINGS

Breathlessness results in avoidance of exertion and deterioration of functional status. Functional impairment leads to care dependency and social limitations, resulting in a change in social role. Anxiety is an emotional response to breathlessness, but also increases the perception of breathlessness. Family caregivers of patients have to cope with changes in daily life, witnessing breathlessness and adapt to new and challenging role as family caregiver.

SUMMARY

The consequences of living with breathlessness are multidimensional and arise in all aspects of daily life of patients, their family caregivers and their social environment. Multidimensional treatment programmes should become widely available to support patients with advanced disease and their family caregivers in coping with the functional, psychological and social consequences of living with breathlessness.

Assessing health-related quality of life in COPD: comparing generic and disease-specific instruments with focus on comorbidities

Background

Chronic Obstructive Pulmonary Disease (COPD) influences different aspects of patient’s health-related quality of life (HRQL). While disease-specific HRQL instruments focus on symptoms and functional impairments, generic instruments cover a broader view on health. This study compares the generic EQ-5D-3 L and two disease-specific questionnaires (St.-George’s Respiratory Questionnaire (SGRQ-C), COPD Assessment Test (CAT)) in a comprehensive spectrum of COPD disease grades with particular attention on comorbidities and assesses the discriminative abilities of these instruments.

Methods

Using data from the baseline visit of the German COPD cohort COSYCONET, mean HRQL scores in different COPD grades were compared by linear regression models adjusting for age, sex, education, smoking status, BMI, and low vs. high number of comorbidities or a list of several self-reported comorbid conditions. Discriminative abilities of HRQL instruments to differentiate between COPD grades were assessed by standardized mean differences.

Results

In 2,291 subjects in COPD GOLD grades 1–4 EQ-5D-3 L utility, EQ-5D VAS, SGRQ, and CAT were found able to discriminate between COPD grades, with some limitations for the EQ-5D utility in mild disease. Both generic and disease-specific HRQL instruments reflected the burden of comorbid conditions. The SGRQ showed the best discrimination between COPD grades and was less influenced by comorbidities, while EQ-5D utility put a higher weight on comorbid conditions. For all instruments, psychiatric disorders and peripheral artery disease showed the strongest negative associations with HRQL.

Conclusion

All HRQL instruments considered reflect considerable impairment of HRQL in COPD patients, worsening with increasing COPD grade and number of comorbidities. Findings may support clinical assessment, choice of HRQL instrument in future studies, and parameterization of decision-analytic models.

Electronic supplementary material

The online version of this article (doi:10.1186/s12890-016-0238-9) contains supplementary material, which is available to authorized users.

The Validity of Disease-specific Quality of Life Attributions Among Adults with Multiple Chronic Conditions

BACKGROUND

A crucial assumption underlying all disease-specific quality of life (QOL) measures, that patients can validly differentiate a specific disease in the presence of multiple chronic conditions, has not been tested using multiple methods. Our objective was to evaluate the convergent and discriminant validity of QOL attributions to specific diseases among adults with multiple chronic conditions (MCC).

METHODS

Adults age 18 and older (N=4,480) sampled from eight pre-identified condition groups (asthma, COPD, angina/MI with angina, congestive heart failure, diabetes, chronic kidney disease, osteoarthritis, rheumatoid arthritis) completed an Internet survey. Comorbid conditions were determined using a 35-condition checklist. Product-moment correlations were analyzed separately by pre-identified condition group using the multitrait-multimethod of construct validation, where traits were defined by 9-26 conditions and each condition was measured by two methods: disease severity rating and Disease-specific Quality of Life Impact Scale (QDIS) global rating. A third method (symptom or clinical marker) was available for the eight pre-identified conditions. Convergent validity was supported when correlations among different methods of measuring the same condition (trait) were substantial (r≥0.40). Discriminant validity was supported when correlations between the same and different methods of measuring different conditions were significantly lower than corresponding convergent correlations.

RESULTS

In support of convergent validity, 22 of 24 convergent correlations were substantial (r=0.38-0.84, median=0.53). In support of discriminant validity, 833 of 924 tests (90.2%) yielded significantly higher convergent than discriminant correlations across the eight pre-identified conditions. Exceptions to this pattern of results were most often observed for comorbid conditions within the same clinical area.

CONCLUSIONS

Collectively, convergent and discriminant test results support the construct validity of disease-specific QOL impact attributions across MCC within the eight pre-identified conditions. Noteworthy exceptions should be considered when interpreting some specific QOL impact attributions and warrant further study. Pursuit of a summary disease-specific QOL impact score standardized across MCC is recommended.

Characteristics of Patients with Chronic Obstructive Pulmonary Disease at the First Visit to a Pulmonary Medical Center in Korea: The KOrea COpd Subgroup Study Team Cohort

The Korea Chronic Obstructive Pulmonary Disorders Subgroup Study Team (Korea COPD Subgroup Study team, KOCOSS) is a multicenter observational study that includes 956 patients (mean age 69.9 ± 7.8 years) who were enrolled from 45 tertiary and university-affiliated hospitals from December 2011 to October 2014. The initial evaluation for all patients included pulmonary function tests (PFT), 6-minute walk distance (6MWD), COPD Assessment Test (CAT), modified Medical Research Council (mMRC) dyspnea scale, and the COPD-specific version of St. George's Respiratory Questionnaire (SGRQ-C). Here, we report the comparison of baseline characteristics between patients with early- (Global Initiative for Chronic Obstructive Lung Disease [GOLD] stage I and II/groups A and B) and late-stage COPD (GOLD stage III and IV/groups C and D). Among all patients, the mean post-bronchodilator FEV1 was 55.8% ± 16.7% of the predicted value, and most of the patients were in GOLD stage II (520, 56.9%) and group B (399, 42.0%). The number of exacerbations during one year prior to the first visit was significantly lower in patients with early COPD (0.4 vs. 0.9/0.1 vs. 1.2), as were the CAT score (13.9 vs. 18.3/13.5 vs. 18.1), mMRC (1.4 vs. 2.0/1.3 vs.1.9), and SGRQ-C total score (30.4 vs. 42.9/29.1 vs. 42.6) compared to late-stage COPD (all P < 0.001). Common comorbidities among all patients were hypertension (323, 37.7%), diabetes mellitus (139, 14.8%), and depression (207, 23.6%). The data from patients with early COPD will provide important information towards early detection, proper initial management, and design of future studies.

Age-Related Differences in Health-Related Quality of Life in COPD: An Analysis of the COPDGene and SPIROMICS Cohorts

OBJECTIVE

Younger persons with COPD report worse health-related quality of life (HRQL) than do older individuals. The factors explaining these differences remain unclear. The objective of this article was to explore factors associated with age-related differences in HRQL in COPD.

METHODS

Cross-sectional analysis of participants with COPD, any Global Initiative for Chronic Obstructive Lung Disease grade of airflow limitation, and ≥ 50 years old in two cohorts: the Genetic Epidemiology of COPD (COPDGene) study and the Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS). We compared St. George's Respiratory Questionnaire (SGRQ) scores by age group: middle-aged (age, 50-64) vs older (age, 65-80) adults. We used multivariate linear modeling to test associations of age with HRQL, adjusting for demographic and clinical characteristics and comorbidities.

RESULTS

Among 4,097 participants in the COPDGene study (2,170 middle-aged and 1,927 older adults) SGRQ total scores were higher (worse) among middle-aged (mean difference, -4.2 points; 95% CI, -5.7 to -2.6; P < .001) than older adults. Age had a statistically significant interaction with dyspnea (P < .001). Greater dyspnea severity (modified Medical Research Council ≥ 2, compared with 0-1) had a stronger association with SGRQ score among middle-aged (β, 24.6; 95% CI, 23.2-25.9) than older-adult (β, 21.0; 95% CI, 19.6-22.3) participants. In analyses using SGRQ as outcome in 1,522 participants in SPIROMICS (598 middle-aged and 924 older adults), we found similar associations, confirming that for the same severity of dyspnea there is a stronger association with HRQL among younger individuals.

CONCLUSIONS

Age-related differences in HRQL may be explained by a higher impact of dyspnea among younger subjects with COPD.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT00608764 and No.: NCT01969344; URL: www.clinicaltrials.gov.

COPD and osteoporosis: links, risks, and treatment challenges

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory airway disease associated with various systemic comorbidities including osteoporosis. Osteoporosis and its related fractures are common and have significant impacts on quality of life and even respiratory function in patients with COPD. COPD-associated osteoporosis is however extremely undertreated. Recent studies have suggested that both decreased bone mineral density (BMD) and impaired bone quality contribute to bone fragility, causing fractures in COPD patients. Various clinical risk factors of osteoporosis in COPD patients, including older age, emaciation, physical inactivity, and vitamin D deficiency, have also been described. It is critically important for pulmonologists to be aware of the high prevalence of osteoporosis in COPD patients and evaluate them for such fracture risks. Routine screening for osteoporosis will enable physicians to diagnose COPD patients with comorbid osteoporosis at an early stage and give them appropriate treatment to prevent fracture, which may lead to improved quality of life as well as better long-term prognosis.