Epidemiology of Adult Pleural Disease in the United States

BACKGROUND

Comprehensive US epidemiologic data for adult pleural disease are not available.

RESEARCH QUESTION

What are the epidemiologic measures related to adult pleural disease in the United States?

STUDY DESIGN AND METHODS

Retrospective cohort study using Healthcare Utilization Project databases (2007-2016). Adults (≥ 18 years of age) with malignant pleural mesothelioma, malignant pleural effusion, nonmalignant pleural effusion, empyema, primary and secondary spontaneous pneumothorax, iatrogenic pneumothorax, and pleural TB were studied.

RESULTS

In 2016, ED treat-and-discharge (T&D) visits totaled 42,215, accounting for charges of $286.7 million. In 2016, a total of 361,270 hospitalizations occurred, resulting in national costs of $10.1 billion. A total of 64,174 readmissions contributed $1.16 billion in additional national costs. Nonmalignant pleural effusion constituted 85.5% of ED T&D visits, 63.5% of hospitalizations, and 66.3% of 30-day readmissions. Contemporary sex distribution (male to female ratio) in primary spontaneous pneumothorax (2.1:1) differs from older estimates (6.2:1). Decadal analyses of annual hospitalization rates/100,000 adult population (2007 vs 2016) showed a significant (P < .001) decrease for malignant pleural mesothelioma (1.3 vs 1.09, respectively), malignant pleural effusion (33.4 vs 31.9, respectively), iatrogenic pneumothorax (17.9 vs 13.9, respectively), and pleural TB (0.20 vs 0.09, respectively) and an increase for empyema (8.1 vs 11.1, respectively) and nonmalignant pleural effusion (78.1 vs 100.1, respectively). Empyema hospitalizations have high costs per case ($38,591) and length of stay (13.8 days). The mean proportion of readmissions attributed to a pleural cause varied widely: malignant pleural mesothelioma, 49%; malignant pleural effusion, 45%; nonmalignant pleural effusion, 31%; empyema, 27%; primary spontaneous pneumothorax, 27%; secondary spontaneous pneumothorax, 27%; and iatrogenic pneumothorax, 20%.

INTERPRETATION

Significant epidemiologic trends and changes in various pleural disease were observed. The analysis identifies multiple opportunities for improvement in management of pleural disease.

Sex and Survival After Surgery for Lung Cancer: A Swedish Nationwide Cohort

BACKGROUND

Prior reports on a possible female survival advantage in both surgical and nonsurgical cohorts of patients with lung cancer are conflicting. Previously reported differences in survival after lung cancer surgery could be the result of insufficient control for disparities in risk factor profiles in men and women.

RESEARCH QUESTION

Do women who undergo pulmonary resections for lung cancer have a better prognosis than men when taking a wide range of prognostic factors into account?

STUDY DESIGN AND METHODS

We performed a nationwide population-based observational cohort study analyzing sex-specific survival after pulmonary resections for lung cancer. We identified 6356 patients from the Swedish National Quality Register for General Thoracic Surgery and performed individual-level record linkage to other national health-data registers to acquire detailed information regarding comorbidity, socioeconomic status, and vital status. Inverse probability of treatment weighting was used to account for differences in baseline characteristics. The association between female sex and all-cause mortality was assessed with Cox regression models, and flexible parametric survival models were used to estimate the absolute survival differences with 95% CIs. We also estimated the difference in restricted mean survival time.

RESULTS

We observed a lower risk of death in women compared with men (hazard ratio, 0.73; 95% CI, 0.67-0.79). The absolute survival difference at 1, 5, and 10 years was 3.0% (95% CI, 2.2%-3.8%), 10% (95% CI, 7.0%-12%), and 12% (95% CI, 8.5%-15%), respectively. The restricted mean survival time difference at 10 years was 0.84 year (95% CI, 0.61-1.07 years). The findings were consistent across several subgroups.

INTERPRETATION

Women who underwent pulmonary resections for lung cancer had a significantly better prognosis than men. The survival advantage was evident regardless of age, common comorbidities, socioeconomic status, lifestyle factors, physical performance, type and extent of surgery, tumor characteristics, and stage of disease.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT03567538; URL: www.clinicaltrials.gov.

Vascular Pruning on CT and Interstitial Lung Abnormalities in the Framingham Heart Study

BACKGROUND

Pulmonary vascular disease is associated with poor outcomes in individuals affected by interstitial lung disease. The pulmonary vessels can be quantified with noninvasive imaging, but whether radiographic indicators of vasculopathy are associated with early interstitial changes is not known.

RESEARCH QUESTION

Are pulmonary vascular volumes, quantified from CT scans, associated with interstitial lung abnormalities (ILA) in a community-based sample with a low burden of lung disease?

STUDY DESIGN AND METHODS

In 2,386 participants of the Framingham Heart Study, we used CT imaging to calculate pulmonary vascular volumes, including the small vessel fraction (a surrogate of vascular pruning). We constructed multivariable logistic regression models to investigate associations of vascular volumes with ILA, progression of ILA, and restrictive pattern on spirometry. In secondary analyses, we additionally adjusted for diffusing capacity and emphysema, and performed a sensitivity analysis restricted to participants with normal FVC and diffusing capacity.

RESULTS

In adjusted models, we found that lower pulmonary vascular volumes on CT were associated with greater odds of ILA, antecedent ILA progression, and restrictive pattern on spirometry. For example, each SD lower small vessel fraction was associated with 1.81-fold greater odds of ILA (95% CI, 1.41-2.31; P < .0001), and 1.63-fold greater odds of restriction on spirometry (95% CI, 1.18-2.24; P = .003). Similar patterns were seen after adjustment for diffusing capacity for carbon monoxide, emphysema, and among participants with normal lung function.

INTERPRETATION

In this cohort of community-dwelling adults not selected on the basis of lung disease, more severe vascular pruning on CT was associated with greater odds of ILA, ILA progression, and restrictive pattern on spirometry. Pruning on CT may be an indicator of early pulmonary vasculopathy associated with interstitial lung disease.

Re-evaluation of the Uplift Clinical Trial Using Age-Appropriate Spirometric Criteria

BACKGROUND

The clinical trial of tiotropium in COPD, UPLIFT, enrolled adults with a mean age of 65 years and moderate-to-severe airflow obstruction, based on criteria from the Global Initiative for Chronic Obstructive Lung Disease (GOLD). For the UPLIFT cohort, however, GOLD-based criteria are not age-appropriate.

RESEARCH QUESTION

Will the use of more age-appropriate criteria for airflow obstruction from the Global Lung Function Initiative (GLI) modify the spirometric classification of the UPLIFT cohort and, in turn, the mortality effect of tiotropium in COPD?

STUDY DESIGN AND METHODS

Baseline spirometric classifications were first cross-tabulated by GLI- and GOLD-based criteria. Next, in GLI- and GOLD-based airflow obstruction, modified intention-to-treat analyses evaluated differences in time to death over 4 years, comparing tiotropium vs placebo. Because treatment response may differ by COPD severity, the mortality effect also was evaluated within stratum defined by GLI- and GOLD-based moderate and severe airflow obstruction.

RESULTS

Of 5,898 participants with GOLD-based airflow-obstruction, staged as moderate in 2,739 (46.4%) and severe in 3,156 (53.5%), GLI-based criteria established airflow obstruction in 5,750 (97.5%), staged as moderate in 795 (13.5%) and severe in 4,947 (83.9%). Relative to placebo, tiotropium yielded statistically nonsignificant adjusted hazard ratios (adjHRs) (95% CI) for death of 0.91 (0.80-1.04) and 0.91 (0.79-1.03) in GLI- and GOLD-based airflow obstruction, respectively. However, statistically significant effect modification was observed, but only in GLI-based moderate and severe airflow-obstruction, with tiotropium yielding adjHRs for death of 0.53 (0.34-0.81) and 0.99 (0.86-1.13), respectively. The P value for interaction was .007.

INTERPRETATION

Mortality reduction by tiotropium was only statistically significant in GLI-based moderate airflow-obstruction, a group that was underrepresented in UPLIFT because of severity misclassification by the original GOLD-based enrollment criteria.

Associations of Serum Adipokines With Subclinical Interstitial Lung Disease Among Community-Dwelling Adults: The Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

Adipokines have inflammatory and fibrotic properties that may be critical in interstitial lung disease (ILD). We examined associations of serum adipokine levels with CT imaging-based measures of subclinical ILD and lung function among community-dwelling adults.

METHODS

A subset of the original Multi-Ethnic Study of Atherosclerosis cohort (n = 1,968) had adiponectin, leptin, and resistin measured during follow-up visits (2002-2005). We used regression models to examine associations of adiponectin, leptin, and resistin levels with (1) high-attenuation areas (HAAs) from CT scans (2004-2005, n = 1,144), (2) interstitial lung abnormalities (ILAs) from CT scans (2010-2012, n = 872), and (3) FVC from spirometry (2004-2006, n = 1,446). We used -(1/HAA²), which we denoted with H, to model HAA as our outcome to meet model assumptions.

RESULTS

Higher adiponectin was associated with lower HAA on CT imaging among adults with a BMI ≥ 25 kg/m² (P for BMI interaction = .07). Leptin was more strongly associated with ILA among never smokers compared with ever smokers (P for smoking interaction = .004). For every 1-SD increment of log-transformed leptin, the percent predicted FVC was 3.8% lower (95% CI, -5.0 to -2.5). Higher serum resistin levels were associated with greater HAA on CT in a fully adjusted model. For every 1-SD increment of log-transformed resistin there was an increase in H of 14.8 (95% CI, 3.4-26.3).

CONCLUSIONS

Higher adiponectin levels were associated with lower HAA on CT imaging among adults with a higher BMI. Higher leptin and resistin levels were associated with lower FVC and greater HAA, respectively.

Early-Life Exposure to Oral Antibiotics and Lung Function Into Early Adulthood

BACKGROUND

Although there is ongoing debate regarding the impact of early postnatal exposure to antibiotics on the development of asthma, the possibility that antibiotic exposure may impair lung function has not previously been examined. Furthermore, it is unclear if specific types of antibiotics may have a greater effect, or if children with genetic mutations in the oxidative stress response glutathione S-transferase (GST) superfamily may be at greater risk.

METHODS

Parent-reported data of childhood antibiotic use from birth to 2 years, including type and indication, were collected from a birth cohort of 620 infants with a family history of allergy. Spirometry was performed at age 12 and 18 years, and results are presented as z scores. Participants were genotyped for GST-P, GST-M, and GST-T polymorphisms. Linear regression models were used to investigate the associations while adjusting for confounding factors.

RESULTS

Neither increasing days of exposure nor earlier exposure to antibiotics was associated with reduced FEV₁ (at 18 years, per doubling of days of exposure = -0.03 z score units; 95% CI, -0.11 to 0.04) or FVC (< 0.01; 95% CI, -0.08 to 0.07). There was no evidence that GST-risk polymorphisms (M1, P1, and T1) increased susceptibility, and specific types of antibiotics also did not increase risk of lung function deficits.

CONCLUSIONS

Increasing exposure to oral antibiotics in early postnatal life was not associated with reduced lung function in children with a family history of allergic diseases. Although unwarranted use of antibiotics in children should be minimized, concerns regarding long-term lung health should not be a driving influence for this rationalization of use.

Interaction of Glutathione S-Transferase M1, T1, and P1 Genes With Early Life Tobacco Smoke Exposure on Lung Function in Adolescents

BACKGROUND

Glutathione S-transferase (GST) genes are involved in the management of oxidative stress in the lungs. We aimed to determine whether they modify the associations between early life smoke exposure and adverse lung health outcomes.

METHODS

The Melbourne Atopy Cohort study (a high-risk birth cohort) enrolled 620 children and followed them prospectively from birth. We recorded perinatal tobacco smoke exposure, asthma, and lung function at 12 (59%) and 18 years (66%) and genotyped for GSTM1, GSTT1, and GSTP1 (69%).

RESULTS

GST genotypes were found to interact with tobacco smoke exposure on lung function outcomes (P interaction ≤ .05). Only among children with GSTT1 null genotypes was exposure to mother's, father's, or parental tobacco smoke in early life associated with an increased risk of reductions in prebronchodilator (BD) FEV₁ and FVC at both 12 and 18 years. These associations were not seen in children with GSTT1 present. Similarly, only among children with GSTM1 null genotypes was exposure to father's or parental smoking associated with reductions in pre- and post-BD FEV₁ and FVC at 18 years. Only among children with Ile/Ile genotypes of GSTP1 was exposure to mother's smoking associated with increased risk of reduced FEV₁ at 18 years, but this was not the case among children with Val/Val or Ile/Val genotypes.

CONCLUSIONS

Our study provides evidence of interaction between early tobacco smoke exposure and GST genotypes on lung function. Carriers of GST null mutations and GSTP1 Ile/Ile alleles may be more susceptible when exposed to tobacco smoke in early life. These findings support stronger recommendations to protect all infants from tobacco smoke exposure.

TRIAL REGISTRY

Australian and New Zealand Clinical Trials Registry; No.: ACTRN12609000734268; URL: http://www.anzctr.org.au/.

Eligibility for Lung Volume Reduction Surgery in Patients With COPD Identified in a UK Primary Care Setting

BACKGROUND

Although lung volume reduction surgery (LVRS) improves survival in appropriately selected patients with COPD, few procedures are performed. The National Institute for Health and Care Excellence has recommended a more systematic approach to identifying potential candidates. We investigated LVRS referrals from a UK primary care population and aimed to establish an accurate estimate of eligible patients and determine a strategy for identifying potential candidates systematically.

METHODS

Clinical Practice Research Datalink GOLD (a primary care database) and the linked Hospital Episode Statistics inpatient and Diagnostic Imaging Dataset were used. Patients with COPD who had undergone LVRS, patients who met basic eligibility criteria for further screening for LVRS, and patients meeting a more stringent eligibility criteria were identified from April 2012 to September 2015. Thoracic CT scan, pulmonary rehabilitation status, referral to respiratory outpatient clinics, and acute exacerbation of COPD requiring hospitalization were compared between actual LVRS recipients and potentially eligible patients.

RESULTS

Among the 73,697 patients with COPD included, 36 (0.05%) received LVRS, 5,984 (8.1%) met basic eligibility criteria, and 159 (0.2%) met more stringent eligibility criteria. LVRS recipients were younger (mean age ± SD, 64 ± 9.2 years) than the stringently eligible patients (mean age ± SD, 69 ± 8.9 years; P = .01). Few patients meeting stringent eligibility criteria (6.9%) had a CT scan of the thorax in the preceding 3 years or had been referred for assessment in secondary care.

CONCLUSIONS

A substantial unmet need exists among patients with COPD who could potentially benefit from a lung volume reduction procedure but who are not being investigated or referred to consider this possibility.

Air Pollution Exposure Is Associated With Lower Lung Function, but Not Changes in Lung Function, in Patients With Idiopathic Pulmonary Fibrosis

BACKGROUND

Air pollution exposure is associated with acute exacerbation, disease progression, and mortality in patients with idiopathic pulmonary fibrosis (IPF). The objective of this study was to describe the impact of air pollution exposures on disease severity, as well as changes in lung function, in patients with IPF.

METHODS

Using home spirometers and symptom diaries, 25 patients with IPF prospectively recorded FVC weekly for up to 40 weeks. Residential addresses were geocoded to estimate weekly mean air pollution exposures for ground-level ozone (O₃), nitrogen dioxide (NO₂), and particulate matter < 2.5 or 10 μm in aerodynamic diameter (PM_2.5 and PM₁₀, respectively). The dependence of weekly clinical measurements on preceding levels of each pollutant was assessed with the use of linear mixed models, yielding beta-coefficients with 95% CIs, using varying lag times.

RESULTS

Lower mean FVC % predicted was consistently associated with increased mean exposures to PM₁₀ in the 2 to 5 weeks preceding clinical measurements (range, -0.46 to -0.39 [95% CI, -0.73 to -0.13]; P < .005). Lower mean FVC % predicted over the study period was inversely related to mean levels of NO₂ (-0.45 [95% CI, -0.85 to -0.05]; P = .03), PM_2.5 (-0.45 [95% CI, -0.84 to -0.07]; P = .02), and PM₁₀ (-0.57 [95% CI, -0.92 to -0.21]; P = .003), averaged over the study. Weekly changes in FVC and changes over 40 weeks were independent of pollution exposures.

CONCLUSIONS

Higher air pollution exposures were associated with lower lung function, but not changes in lung function, in patients with IPF. Further studies are needed to characterize the mechanisms underlying this relationship.

Exhaled Nitric Oxide Levels Among Adults With Excessive Alcohol Consumption

BACKGROUND

More than one-quarter of the US population qualify as excessive alcohol consumers. Alcohol use impacts several lung diseases, and heavy consumption has been associated with poor clinical outcomes. The fractional excretion of exhaled nitric oxide (Feno) has clinical implications in multiple airways diseases. We hypothesized that excessive alcohol intake is associated with lower Feno levels.

METHODS

To test this hypothesis, we examined a sample consisting of 12,059 participants, aged 21 to 79 years, interviewed between 2007 and 2012 from the National Health and Examination Survey. Two valid Feno measurements that were reproducible were recorded. Alcohol questionnaire data were used to define the following alcohol groups: never drinkers, nonexcessive drinkers, excessive drinkers, and former excessive drinkers. The natural logarithm of Feno values [ln(Feno)] as well as blood eosinophil count and C-reactive protein were used as dependent variables to test the association with alcohol groups including multivariable linear regression models with adjustment for predictors of Feno.

RESULTS

Excessive alcohol consumption comprised 3,693 (26.9%) of the US sample population. Controlling for all other factors, excessive alcohol consumption had a negative association and was an independent predictor for ln(Feno) levels in comparison with the never-drinker group (-0.11; 95% CI, -0.17 to -0.06; P < .001). ln(Feno) levels decreased across categories of increasing alcohol use (P < .001).

CONCLUSIONS

Accounting for alcohol use in the interpretation of Feno levels should be an additional consideration, and further investigations are warranted to explore the complex interaction between alcohol and nitric oxide in the airways.

Sex-Specific Prediction Models for Sleep Apnea From the Hispanic Community Health Study/Study of Latinos

OBJECTIVE

We developed and validated the first-ever sleep apnea (SA) risk calculator in a large population-based cohort of Hispanic/Latino subjects.

METHODS

Cross-sectional data on adults from the Hispanic Community Health Study/Study of Latinos (2008-2011) were analyzed. Subjective and objective sleep measurements were obtained. Clinically significant SA was defined as an apnea-hypopnea index ≥ 15 events per hour. Using logistic regression, four prediction models were created: three sex-specific models (female-only, male-only, and a sex × covariate interaction model to allow differential predictor effects), and one overall model with sex included as a main effect only. Models underwent 10-fold cross-validation and were assessed by using the C statistic. SA and its predictive variables; a total of 17 variables were considered.

RESULTS

A total of 12,158 participants had complete sleep data available; 7,363 (61%) were women. The population-weighted prevalence of SA (apnea-hypopnea index ≥ 15 events per hour) was 6.1% in female subjects and 13.5% in male subjects. Male-only (C statistic, 0.808) and female-only (C statistic, 0.836) prediction models had the same predictor variables (ie, age, BMI, self-reported snoring). The sex-interaction model (C statistic, 0.836) contained sex, age, age × sex, BMI, BMI × sex, and self-reported snoring. The final overall model (C statistic, 0.832) contained age, BMI, snoring, and sex. We developed two websites for our SA risk calculator: one in English (https://www.montefiore.org/sleepapneariskcalc.html) and another in Spanish (http://www.montefiore.org/sleepapneariskcalc-es.html).

CONCLUSIONS

We created an internally validated, highly discriminating, well-calibrated, and parsimonious prediction model for SA. Contrary to the study hypothesis, the variables did not have different predictive magnitudes in male and female subjects.

Drug Treatment of Idiopathic Pulmonary Fibrosis: Systematic Review and Network Meta-Analysis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a form of chronic progressive fibrosing interstitial lung disease of unknown origin. Recently, nintedanib and pirfenidone demonstrated efficacy in slowing disease progression and were approved by the US Food and Drug Administration. Although numerous treatments have been evaluated in IPF, none have shown significant decreases in mortality. The objective of this study was to identify all pharmacologic treatments evaluated for IPF and analyze their efficacy via Bayesian network meta-analysis and pairwise indirect treatment comparisons. This review did not evaluate the effect of steroid therapy.

METHODS

We searched MEDLINE, Embase, and the Cochrane Library for studies published on or before August 2014. Studies were required to contain a randomized evaluation of nonsteroidal drug therapy for treatment of IPF and be published in English. Key outcomes of interest for this analysis were pulmonary function as measured by FVC as well as all-cause and respiratory-specific death. All outcomes were analyzed via a Bayesian framework.

RESULTS

Our review identified 30 eligible studies that evaluated 16 unique treatments. Under both the fixed-effect and random-effect models for respiratory-specific mortality, no treatments performed better than placebo. For all-cause mortality, pirfenidone and nintedanib had effects approaching significance with credible intervals slightly crossing the null under a fixed-effect model. Notably, for respiratory-specific mortality, all-cause mortality, and decline in percent predicted FVC, nintedanib and pirfenidone were virtually indistinguishable and no clear advantage was detected.

CONCLUSIONS

Although two treatments have been approved for IPF on the basis of reduced decline in pulmonary function, neither one has a clear advantage on mortality outcomes.

A Simple Derived Prediction Score for the Identification of an Elevated Pulmonary Artery Wedge Pressure Using Precatheterization Clinical Data in Patients Referred to a Pulmonary Hypertension Center

BACKGROUND

One of the foremost diagnostic challenges in clinical pulmonary hypertension is discriminating between pulmonary arterial hypertension (group 1) and heart failure with preserved ejection fraction (group 2.2). Group 2.2 is defined as a normal left ventricular ejection fraction (> 50%) and a pulmonary arterial wedge pressure (PAWP) > 15 mm Hg. We aimed to determine whether patient history, demographics, and noninvasive measures could predict PAWP before to right heart catheterization.

METHODS

Data were prospectively collected on 350 consecutive patients at a single tertiary care medical center; of these patients, 151 met criteria for entry into our study (88 in group 1 and 63 in group 2.2). Data included historical features, demographics, and results of a transthoracic echocardiogram. A multivariate regression model was developed to predict PAWP > 15 mm Hg.

RESULTS

Univariate predictors of PAWP > 15 mm Hg included older age, higher BMI and weight, systemic systolic BP and pulse pressure, more features of the metabolic syndrome, presence of hypertension and left atrial enlargement, absence of right ventricular enlargement, and lower glomerular filtration rate and 6-min walk distance. The optimal model for predicting PAWP > 15 mm Hg was composed of age (> 68 years), BMI (> 30 kg/m(2)), absence of right ventricular enlargement, and presence of left atrial enlargement (area under the curve, 0.779).

CONCLUSIONS

Clinical characteristics obtained before diagnostic right heart catheterization accurately predict the probability of elevation of PAWP > 15 mm Hg in patients with preserved ejection fraction. These combined clinical characteristics can be used a priori to predict the likelihood of group 2.2 pulmonary hypertension.

Comorbidome, Pattern, and Impact of Asthma-COPD Overlap Syndrome in Real Life

BACKGROUND

Asthma-COPD overlap syndrome (ACOS) has been described and acknowledged as a distinct clinical entity; however, its characteristics in daily clinical practice are largely unknown. The aim of this study was to identify the prevalence of ACOS in the real-life population, its pattern of comorbidities, and its impact on hospitalization risk.

METHODS

Data for this retrospective cohort study were extracted from the Majorca Real-Life Investigation in COPD and Asthma cohort, including primary care, hospitalization, and pharmacy data from the Balearic Islands, Spain. Patients who had received a physician-confirmed diagnosis of both asthma and COPD were identified as having ACOS and compared with a COPD-only population. In subanalyses, more stringent diagnostic criteria (Global Initiative for Asthma-Global Initiative for Chronic Obstructive Lung Disease) were applied. The pattern and impact of comorbidities on all-cause hospitalization were compared by multivariate logistic regression.

RESULTS

In total, 5,093 patients with ACOS (prevalence, 5.55 per 1,000 inhabitants) were compared with 22,778 patients with COPD (30.40 per 1,000 inhabitants). Patients with ACOS were more frequently female (53.4%) than were patients with COPD (30.8%), younger (ACOS, 64.0 years; COPD, 65.8 years), and differed by nonsmoking status (ACOS, 41.4%; COPD, 22.1%) (all, P < .001). In adjusted analyses, allergic rhinitis (OR, 1.81; 95% CI, 1.63-2.00), anxiety (OR, 1.18; 95% CI, 1.10-1.27), gastroesophageal reflux disease (OR, 1.18; 95% CI, 1.04-1.33), and osteoporosis (OR, 1.14; 95% CI, 1.04-1.26) were more frequent in ACOS than COPD. In contrast, chronic kidney disease (OR, 0.79; 95% CI, 0.66-0.95) and ischemic heart disease (OR, 0.88; 95% CI, 0.79-0.98) were less frequent. In patients with ACOS, cardiovascular diseases showed the strongest association with hospitalization.

CONCLUSIONS

ACOS is prevalent in the general population, and it affects to a large extent females with less smoking exposure compared with patients with COPD only. Cardiovascular comorbidities in particular contribute most to overall hospitalization risk of patients with ACOS.