@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} } @article {9156, title = {Pooled Cohort Probability Score for Subclinical Airflow Obstruction.}, journal = {Ann Am Thorac Soc}, volume = {19}, year = {2022}, month = {2022 08}, pages = {1294-1304}, abstract = {

Early detection of chronic obstructive pulmonary disease (COPD) is a public health priority. Airflow obstruction is the single most important risk factor for adverse COPD outcomes, but spirometry is not routinely recommended for screening. To describe the burden of subclinical airflow obstruction (SAO) and to develop a probability score for SAO to inform potential detection and prevention programs. Lung function and clinical data were harmonized and pooled across nine U.S. general population cohorts. Adults with respiratory symptoms, inhaler use, or prior diagnosis of COPD or asthma were excluded. A probability score for prevalent SAO (forced expiratory volume in 1 second/forced vital capacity < 0.70) was developed via hierarchical group-lasso regularization from clinical variables in strata of sex and smoking status, and its discriminative accuracy for SAO was assessed in the pooled cohort as well as in an external validation cohort (NHANES [National Health and Nutrition Examination Survey] 2011-2012). Incident hospitalizations and deaths due to COPD (respiratory events) were defined by adjudication or administrative criteria in four of nine cohorts. Of 33,546 participants (mean age 52 yr, 54\% female, 44\% non-Hispanic White), 4,424 (13.2\%) had prevalent SAO. The incidence of respiratory events ( = 14,024) was threefold higher in participants with SAO versus those without (152 vs. 39 events/10,000 person-years). The probability score, which was based on six commonly available variables (age, sex, race and/or ethnicity, body mass index, smoking status, and smoking pack-years) was well calibrated and showed excellent discrimination in both the testing sample (C-statistic, 0.81; 95\% confidence interval [CI], 0.80-0.82) and in NHANES (C-statistic, 0.83; 95\% CI, 0.80-0.86). Among participants with predicted probabilities ⩾ 15\%, 3.2 would need to undergo spirometry to detect one case of SAO. Adults with SAO demonstrate excess respiratory hospitalization and mortality. A probability score for SAO using commonly available clinical risk factors may be suitable for targeting screening and primary prevention strategies.

}, keywords = {Adult, Female, Forced Expiratory Volume, Humans, Lung, Male, Middle Aged, Nutrition Surveys, Pulmonary Disease, Chronic Obstructive, Risk Factors, Spirometry, Vital Capacity}, issn = {2325-6621}, doi = {10.1513/AnnalsATS.202109-1020OC}, author = {Bhatt, Surya P and Balte, Pallavi P and Schwartz, Joseph E and Jaeger, Byron C and Cassano, Patricia A and Chaves, Paulo H and Couper, David and Jacobs, David R and Kalhan, Ravi and Kaplan, Robert and Lloyd-Jones, Donald and Newman, Anne B and O{\textquoteright}Connor, George and Sanders, Jason L and Smith, Benjamin M and Sun, Yifei and Umans, Jason G and White, Wendy B and Yende, Sachin and Oelsner, Elizabeth C} } @article {9902, title = {Low Lung Function Is Associated with High Population Attributable Fraction for Cardiovascular Mortality.}, journal = {Ann Am Thorac Soc}, volume = {22}, year = {2025}, month = {2025 Mar}, pages = {359-366}, abstract = {

Chronic lung diseases are associated with increased risk of mortality due to coronary heart disease (CHD). Nonetheless, the population attributable fraction (PAF) of lung function impairment relative to other established cardiovascular risk factors is unclear. To evaluate the PAF of low lung function for CHD mortality We harmonized and pooled lung function and clinical data across eight U.S. general population cohorts. Impaired lung function was defined as forced expiratory volume in 1 second (FEV) and/or forced vital capacity <= 95\% predicted on baseline spirometry. The association between CHD mortality and risk factors was assessed using cause-specific proportional hazards and Fine-Gray proportional subdistribution hazard models, treating non-CHD mortality as a competing risk. Models were adjusted for lung function as well as age, sex, race/ethnicity, educational attainment, body mass index, smoking status, pack-years of smoking, diabetes mellitus, high-density lipoprotein, and high low-density lipoprotein (>=130 mg/dl). PAF was calculated as the relative change in the average absolute risk of 10-year CHD mortality by elimination of lung function lower than 95\% predicted. Among 35,143 participants, 1,844 of 13,174 (14.0\%) deaths were due to CHD. Compared with percentage predicted FEV (FEVpp) > 95\%, the subdistribution adjusted hazard ratio for low FEVpp was 1.30 (95\% confidence interval, 1.18-1.44). The PAF for FEVpp <= 95\% was 12\%, ranking low FEV third on the list of PAF for CHD mortality, after hypertension and diabetes. Low FEVpp ranked second in the subgroup of active smokers (PAF 14\%), after hypertension. Low lung function, even in the range considered clinically normal, ranks high on the list of attributable risk factors for CHD mortality and should be considered in cardiovascular risk stratification.

}, keywords = {Adult, Aged, Coronary Disease, Female, Forced Expiratory Volume, Humans, Lung, Lung Diseases, Male, Middle Aged, Proportional Hazards Models, Risk Factors, Smoking, Spirometry, United States, Vital Capacity}, issn = {2325-6621}, doi = {10.1513/AnnalsATS.202407-715OC}, author = {Bhatt, Surya P and Wu, Chaoqi and Sun, Yifei and Balte, Pallavi P and Schwartz, Joseph E and Divo, Miguel J and Jaeger, Byron C and Chaves, Paulo H and Couper, David and Jacobs, David R and Lloyd-Jones, Donald and Kalhan, Ravi and Newman, Anne B and O{\textquoteright}Connor, George T and Umans, Jason G and White, Wendy B and Yende, Sachin and Oelsner, Elizabeth C} }