@article {8097, title = {Discriminative Accuracy of FEV1:FVC Thresholds for COPD-Related Hospitalization and Mortality.}, journal = {JAMA}, volume = {321}, year = {2019}, month = {2019 06 25}, pages = {2438-2447}, abstract = {

Importance: According to numerous current guidelines, the diagnosis of chronic obstructive pulmonary disease (COPD) requires a ratio of the forced expiratory volume in the first second to the forced vital capacity (FEV1:FVC) of less than 0.70, yet this fixed threshold is based on expert opinion and remains controversial.

Objective: To determine the discriminative accuracy of various FEV1:FVC fixed thresholds for predicting COPD-related hospitalization and mortality.

Design, Setting, and Participants: The National Heart, Lung, and Blood Institute (NHLBI) Pooled Cohorts Study harmonized and pooled data from 4 US general population-based cohorts (Atherosclerosis Risk in Communities Study; Cardiovascular Health Study; Health, Aging, and Body Composition Study; and Multi-Ethnic Study of Atherosclerosis). Participants aged 45 to 102 years were enrolled from 1987 to 2000 and received follow-up longitudinally through 2016.

Exposures: Presence of airflow obstruction, which was defined by a baseline FEV1:FVC less than a range of fixed thresholds (0.75 to 0.65) or less than the lower limit of normal as defined by Global Lung Initiative reference equations (LLN).

Main Outcomes and Measures: The primary outcome was a composite of COPD hospitalization and COPD-related mortality, defined by adjudication or administrative criteria. The optimal fixed FEV1:FVC threshold was defined by the best discrimination for these COPD-related events as indexed using the Harrell C statistic from unadjusted Cox proportional hazards models. Differences in C statistics were compared with respect to less than 0.70 and less than LLN thresholds using a nonparametric approach.

Results: Among 24 207 adults in the pooled cohort (mean [SD] age at enrollment, 63 [10.5] years; 12 990 [54\%] women; 16 794 [69\%] non-Hispanic white; 15 181 [63\%] ever smokers), complete follow-up was available for 11 077 (77\%) at 15 years. During a median follow-up of 15 years, 3925 participants experienced COPD-related events over 340 757 person-years of follow-up (incidence density rate, 11.5 per 1000 person-years), including 3563 COPD-related hospitalizations and 447 COPD-related deaths. With respect to discrimination of COPD-related events, the optimal fixed threshold (0.71; C statistic for optimal fixed threshold, 0.696) was not significantly different from the 0.70 threshold (difference, 0.001 [95\% CI, -0.002 to 0.004]) but was more accurate than the LLN threshold (difference, 0.034 [95\% CI, 0.028 to 0.041]). The 0.70 threshold provided optimal discrimination in the subgroup analysis of ever smokers and in adjusted models.

Conclusions and Relevance: Defining airflow obstruction as FEV1:FVC less than 0.70 provided discrimination of COPD-related hospitalization and mortality that was not significantly different or was more accurate than other fixed thresholds and the LLN. These results support the use of FEV1:FVC less than 0.70 to identify individuals at risk of clinically significant COPD.

}, keywords = {Aged, Aged, 80 and over, Cohort Studies, Female, Forced Expiratory Volume, Hospitalization, Humans, Male, Middle Aged, Prognosis, Proportional Hazards Models, Pulmonary Disease, Chronic Obstructive, Risk Assessment, Vital Capacity}, issn = {1538-3598}, doi = {10.1001/jama.2019.7233}, author = {Bhatt, Surya P and Balte, Pallavi P and Schwartz, Joseph E and Cassano, Patricia A and Couper, David and Jacobs, David R and Kalhan, Ravi and O{\textquoteright}Connor, George T and Yende, Sachin and Sanders, Jason L and Umans, Jason G and Dransfield, Mark T and Chaves, Paulo H and White, Wendy B and Oelsner, Elizabeth C} } @article {8620, title = {Association of Nonobstructive Chronic Bronchitis With Respiratory Health Outcomes in Adults.}, journal = {JAMA Intern Med}, volume = {180}, year = {2020}, month = {2020 05 01}, pages = {676-686}, abstract = {

Importance: Chronic bronchitis has been associated with cigarette smoking as well as with e-cigarette use among young adults, but the association of chronic bronchitis in persons without airflow obstruction or clinical asthma, described as nonobstructive chronic bronchitis, with respiratory health outcomes remains uncertain.

Objective: To assess whether nonobstructive chronic bronchitis is associated with adverse respiratory health outcomes in adult ever smokers and never smokers.

Design, Setting, and Participants: This prospective cohort study included 22 325 adults without initial airflow obstruction (defined as the ratio of forced expiratory volume in the first second [FEV1] to forced vital capacity [FVC] of <0.70) or clinical asthma at baseline. The National Heart, Lung, and Blood Institute (NHLBI) Pooled Cohorts Study harmonized and pooled data from 9 US general population-based cohorts. Thus present study is based on data from 5 of these cohorts. Participants were enrolled from August 1971 through May 2007 and were followed up through December 2018.

Exposures: Nonobstructive chronic bronchitis was defined by questionnaire at baseline as both cough and phlegm for at least 3 months for at least 2 consecutive years.

Main Outcomes and Measures: Lung function was measured by prebronchodilator spirometry. Hospitalizations and deaths due to chronic lower respiratory disease and respiratory disease-related mortality were defined by events adjudication and administrative criteria. Models were stratified by smoking status and adjusted for anthropometric, sociodemographic, and smoking-related factors. The comparison group was participants without nonobstructive chronic bronchitis.

Results: Among 22 325 adults included in the analysis, mean (SD) age was 53.0 (16.3) years (range, 18.0-95.0 years), 58.2\% were female, 65.9\% were non-Hispanic white, and 49.6\% were ever smokers. Among 11 082 ever smokers with 99 869 person-years of follow-up, participants with nonobstructive chronic bronchitis (300 [2.7\%]) had accelerated decreases in FEV1 (4.1 mL/y; 95\% CI, 2.1-6.1 mL/y) and FVC (4.7 mL/y; 95\% CI, 2.2-7.2 mL/y), increased risks of chronic lower respiratory disease-related hospitalization or mortality (hazard ratio [HR], 2.2; 95\% CI, 1.7-2.7), and greater respiratory disease-related (HR, 2.0; 95\% CI, 1.1-3.8) and all-cause mortality (HR, 1.5; 95\% CI, 1.3-1.8) compared with ever smokers without nonobstructive chronic bronchitis. Among 11 243 never smokers with 120 004 person-years of follow-up, participants with nonobstructive chronic bronchitis (151 [1.3\%]) had greater rates of chronic lower respiratory disease-related hospitalization or mortality (HR, 3.1; 95\% CI, 2.1-4.5) compared with never smokers without nonobstructive chronic bronchitis. Nonobstructive chronic bronchitis was not associated with FEV1:FVC decline or incident airflow obstruction. The presence of at least 1 of the component symptoms of nonobstructive chronic bronchitis (ie, chronic cough or phlegm), which was common in both ever smokers (11.0\%) and never smokers (6.7\%), was associated with adverse respiratory health outcomes.

Conclusions and Relevance: The findings suggest that nonobstructive chronic bronchitis is associated with adverse respiratory health outcomes, particularly in ever smokers, and may be a high-risk phenotype suitable for risk stratification and targeted therapies.

}, keywords = {Adolescent, Adult, Aged, Aged, 80 and over, Asthma, Bronchitis, Chronic, Female, Humans, Lung, Male, Middle Aged, Prospective Studies, Respiratory Function Tests, Smokers, Smoking, Young Adult}, issn = {2168-6114}, doi = {10.1001/jamainternmed.2020.0104}, author = {Balte, Pallavi P and Chaves, Paulo H M and Couper, David J and Enright, Paul and Jacobs, David R and Kalhan, Ravi and Kronmal, Richard A and Loehr, Laura R and London, Stephanie J and Newman, Anne B and O{\textquoteright}Connor, George T and Schwartz, Joseph E and Smith, Benjamin M and Smith, Lewis J and White, Wendy B and Yende, Sachin and Oelsner, Elizabeth C} } @article {8623, title = {A Dyadic Growth Modeling Approach for Examining Associations Between Weight Gain and Lung Function Decline.}, journal = {Am J Epidemiol}, volume = {189}, year = {2020}, month = {2020 10 01}, pages = {1173-1184}, abstract = {

The relationship between body weight and lung function is complex. Using a dyadic multilevel linear modeling approach, treating body mass index (BMI; weight (kg)/height (m)2) and lung function as paired, within-person outcomes, we tested the hypothesis that persons with more rapid increase in BMI exhibit more rapid decline in lung function, as measured by forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and their ratio (FEV1:FVC). Models included random intercepts and slopes and adjusted for sociodemographic and smoking-related factors. A sample of 9,115 adults with paired measurements of BMI and lung function taken at >=3 visits were selected from a pooled set of 5 US population-based cohort studies (1983-2018; mean age at baseline = 46 years; median follow-up, 19 years). At age 46 years, average annual rates of change in BMI, FEV1, FVC, and FEV1:FVC ratio were 0.22 kg/m2/year, -25.50 mL/year, -21.99 mL/year, and~-0.24\%/year, respectively. Persons with steeper BMI increases had faster declines in FEV1 (r~=~-0.16) and FVC (r~=~-0.26) and slower declines in FEV1:FVC ratio (r~=~0.11) (all P~values <~0.0001). Results were similar in subgroup analyses. Residual correlations were negative (P~<~0.0001), suggesting additional interdependence between BMI and lung function. Results show that greater rates of weight gain are associated with greater rates of lung function loss.

}, keywords = {Adult, Aged, Body Mass Index, Cohort Studies, Humans, Linear Models, Lung, Middle Aged, Respiratory Function Tests, Weight Gain}, issn = {1476-6256}, doi = {10.1093/aje/kwaa059}, author = {Cornelius, Talea and Schwartz, Joseph E and Balte, Pallavi and Bhatt, Surya P and Cassano, Patricia A and Currow, David and Jacobs, David R and Johnson, Miriam and Kalhan, Ravi and Kronmal, Richard and Loehr, Laura and O{\textquoteright}Connor, George T and Smith, Benjamin and White, Wendy B and Yende, Sachin and Oelsner, Elizabeth C} } @article {8402, title = {Lung function decline in former smokers and low-intensity current smokers: a secondary data analysis of the NHLBI Pooled Cohorts Study.}, journal = {Lancet Respir Med}, volume = {8}, year = {2020}, month = {2020 01}, pages = {34-44}, abstract = {

BACKGROUND: Former smokers now outnumber current smokers in many developed countries, and current smokers are smoking fewer cigarettes per day. Some data suggest that lung function decline normalises with smoking cessation; however, mechanistic studies suggest that lung function decline could continue. We hypothesised that former smokers and low-intensity current smokers have accelerated lung function decline compared with never-smokers, including among those without prevalent lung disease.

METHODS: We used data on six US population-based cohorts included in the NHLBI Pooled Cohort Study. We restricted the sample to participants with valid spirometry at two or more exams. Two cohorts recruited younger adults (>=17 years), two recruited middle-aged and older adults (>=45 years), and two recruited only elderly adults (>=65 years) with examinations done between 1983 and 2014. FEV decline in sustained former smokers and current smokers was compared to that of never-smokers by use of mixed models adjusted for sociodemographic and anthropometric factors. Differential FEV decline was also evaluated according to duration of smoking cessation and cumulative (number of pack-years) and current (number of cigarettes per day) cigarette consumption.

FINDINGS: 25 352 participants (ages 17-93 years) completed 70 228 valid spirometry exams. Over a median follow-up of 7 years (IQR 3-20), FEV decline at the median age (57 years) was 31{\textperiodcentered}01 mL per year (95\% CI 30{\textperiodcentered}66-31{\textperiodcentered}37) in sustained never-smokers, 34{\textperiodcentered}97 mL per year (34{\textperiodcentered}36-35{\textperiodcentered}57) in former smokers, and 39{\textperiodcentered}92 mL per year (38{\textperiodcentered}92-40{\textperiodcentered}92) in current smokers. With adjustment, former smokers showed an accelerated FEV decline of 1{\textperiodcentered}82 mL per year (95\% CI 1{\textperiodcentered}24-2{\textperiodcentered}40) compared to never-smokers, which was approximately 20\% of the effect estimate for current smokers (9{\textperiodcentered}21 mL per year; 95\% CI 8{\textperiodcentered}35-10{\textperiodcentered}08). Compared to never-smokers, accelerated FEV decline was observed in former smokers for decades after smoking cessation and in current smokers with low cumulative cigarette consumption (<10 pack-years). With respect to current cigarette consumption, the effect estimate for FEV decline in current smokers consuming less than five cigarettes per day (7{\textperiodcentered}65 mL per year; 95\% CI 6{\textperiodcentered}21-9{\textperiodcentered}09) was 68\% of that in current smokers consuming 30 or more cigarettes per day (11{\textperiodcentered}24 mL per year; 9{\textperiodcentered}86-12{\textperiodcentered}62), and around five times greater than in former smokers (1{\textperiodcentered}57 mL per year; 1{\textperiodcentered}00-2{\textperiodcentered}14). Among participants without prevalent lung disease, associations were attenuated but were consistent with the main results.

INTERPRETATION: Former smokers and low-intensity current smokers have accelerated lung function decline compared with never-smokers. These results suggest that all levels of smoking exposure are likely to be associated with lasting and progressive lung damage.

FUNDING: National Institutes of Health, National Heart Lung and Blood Institute, and US Environmental Protection Agency.

}, keywords = {Adult, Aged, Case-Control Studies, Ex-Smokers, Female, Follow-Up Studies, Humans, Lung, Male, Middle Aged, National Heart, Lung, and Blood Institute (U.S.), Non-Smokers, Respiratory Physiological Phenomena, Smokers, Smoking, Spirometry, United States, Young Adult}, issn = {2213-2619}, doi = {10.1016/S2213-2600(19)30276-0}, author = {Oelsner, Elizabeth C and Balte, Pallavi P and Bhatt, Surya P and Cassano, Patricia A and Couper, David and Folsom, Aaron R and Freedman, Neal D and Jacobs, David R and Kalhan, Ravi and Mathew, Amanda R and Kronmal, Richard A and Loehr, Laura R and London, Stephanie J and Newman, Anne B and O{\textquoteright}Connor, George T and Schwartz, Joseph E and Smith, Lewis J and White, Wendy B and Yende, Sachin} } @article {9114, title = {Association Between Preserved Ratio Impaired Spirometry and Clinical Outcomes in US Adults.}, journal = {JAMA}, volume = {326}, year = {2021}, month = {2021 12 14}, pages = {2287-2298}, abstract = {

Importance: Chronic lung diseases are a leading cause of morbidity and mortality. Unlike chronic obstructive pulmonary disease, clinical outcomes associated with proportional reductions in expiratory lung volumes without obstruction, otherwise known as preserved ratio impaired spirometry (PRISm), are poorly understood.

Objective: To examine the prevalence, correlates, and clinical outcomes associated with PRISm in US adults.

Design, Setting, and Participants: The National Heart, Lung, and Blood Institute (NHLBI) Pooled Cohorts Study was a retrospective study with harmonized pooled data from 9 US general population-based cohorts (enrollment, 65 251 participants aged 18 to 102 years of whom 53 701 participants had valid baseline lung function) conducted from 1971-2011 (final follow-up, December 2018).

Exposures: Participants were categorized into mutually exclusive groups by baseline lung function. PRISm was defined as the ratio of forced expiratory volume in the first second to forced vital capacity (FEV1:FVC) greater than or equal to 0.70 and FEV1 less than 80\% predicted; obstructive spirometry FEV1:FVC ratio of less than 0.70; and normal spirometry FEV1:FVC ratio greater than or equal to 0.7 and FEV1 greater than or equal to 80\% predicted.

Main Outcomes and Measures: Main outcomes were all-cause mortality, respiratory-related mortality, coronary heart disease (CHD)-related mortality, respiratory-related events (hospitalizations and mortality), and CHD-related events (hospitalizations and mortality) classified by adjudication or validated administrative criteria. Absolute risks were adjusted for age and smoking status. Poisson and Cox proportional hazards models comparing PRISm vs normal spirometry were adjusted for age, sex, race and ethnicity, education, body mass index, smoking status, cohort, and comorbidities.

Results: Among all participants (mean [SD] age, 53.2 [15.8] years, 56.4\% women, 48.5\% never-smokers), 4582 (8.5\%) had PRISm. The presence of PRISm relative to normal spirometry was significantly associated with obesity (prevalence, 48.3\% vs 31.4\%; prevalence ratio [PR], 1.68 [95\% CI, 1.55-1.82]), underweight (prevalence, 1.4\% vs 1.0\%; PR, 2.20 [95\% CI, 1.72-2.82]), female sex (prevalence, 60.3\% vs 59.0\%; PR, 1.07 [95\% CI, 1.01-1.13]), and current smoking (prevalence, 25.2\% vs 17.5\%; PR, 1.33 [95\% CI, 1.22-1.45]). PRISm, compared with normal spirometry, was significantly associated with greater all-cause mortality (29.6/1000 person-years vs 18.0/1000 person-years; difference, 11.6/1000 person-years [95\% CI, 10.0-13.1]; adjusted hazard ratio [HR], 1.50 [95\% CI, 1.42-1.59]), respiratory-related mortality (2.1/1000 person-years vs 1.0/1000 person-years; difference, 1.1/1000 person-years [95\% CI, 0.7-1.6]; adjusted HR, 1.95 [95\% CI, 1.54-2.48]), CHD-related mortality (5.4/1000 person-years vs 2.6/1000 person-years; difference, 2.7/1000 person-years [95\% CI, 2.1-3.4]; adjusted HR, 1.55 [95\% CI, 1.36-1.77]), respiratory-related events (12.2/1000 person-years vs 6.0/1000 person-years; difference, 6.2/1000 person-years [95\% CI, 4.9-7.5]; adjusted HR, 1.90 [95\% CI, 1.69-2.14]), and CHD-related events (11.7/1000 person-years vs 7.0/1000 person-years; difference, 4.7/1000 person-years [95\% CI, 3.7-5.8]; adjusted HR, 1.30 [95\% CI, 1.18-1.42]).

Conclusions and Relevance: In a large, population-based sample of US adults, baseline PRISm, compared with normal spirometry, was associated with a small but statistically significant increased risk for mortality and adverse cardiovascular and respiratory outcomes. Further research is needed to explore whether this association is causal.

}, keywords = {Adult, Aged, Aged, 80 and over, Cardiovascular Diseases, Female, Forced Expiratory Volume, Humans, Lung, Lung Diseases, Male, Middle Aged, Prevalence, Retrospective Studies, Spirometry, United States, Vital Capacity}, issn = {1538-3598}, doi = {10.1001/jama.2021.20939}, author = {Wan, Emily S and Balte, Pallavi and Schwartz, Joseph E and Bhatt, Surya P and Cassano, Patricia A and Couper, David and Daviglus, Martha L and Dransfield, Mark T and Gharib, Sina A and Jacobs, David R and Kalhan, Ravi and London, Stephanie J and Navas-Acien, Ana and O{\textquoteright}Connor, George T and Sanders, Jason L and Smith, Benjamin M and White, Wendy and Yende, Sachin and Oelsner, Elizabeth C} }