Significant predictors of medically diagnosed chronic obstructive pulmonary disease in patients with preserved ratio impaired spirometry: a 3-year cohort study

Increased postoperative complications after laparoscopic gastrectomy in patients with preserved ratio impaired spirometry

BACKGROUND

Preserved ratio impaired spirometry (PRISm), defined as decreased forced expiratory volume in the first second in the setting of normal ratio, is associated with an increased risk of respiratory disease and systemic comorbidities. Unlike severe obstructive pulmonary disease, little is known about the impact of PRISm on short-term outcomes in patients undergoing laparoscopic gastrectomy (LG) and its association with small airway dysfunction (SAD).

METHODS

This study enrolled 830 patients who underwent preoperative spirometry and LG between January 2021 and August 2023. Of these, 228 patients were excluded. Participants were categorized into 3 groups based on their baseline lung function, and postoperative outcomes were subsequently analyzed. Potential associations between postoperative outcomes and various clinical variables were examined using univariate and multivariate analyses.

RESULTS

PRISm was identified in 16.6% of the patients, whereas SAD was present in 20.4%. The incidence of postoperative pulmonary complications (PPCs) was notably higher in the SAD group (20.3% vs 9.8%, P = .002) and the PRISm group (28.0% vs 9.8%, P < .001) than the normal group. Among the 3 groups, pneumonia was the most frequently observed PPC. Multivariate analysis revealed that both SAD (odds ratio [OR], 2.34; 95% CI, 1.30-4.22; P = .005) and PRISm (OR, 3.26; 95% CI, 1.80-5.90; P < .001) independently constituted significant risk factors associated with the occurrence of PPCs. Univariate analysis showed that female was a possible risk factor for PPCs in PRISm group.

CONCLUSION

Our study showed that PRISm and SAD were associated with the increased PPCs in patients undergoing LG for gastric cancer.

Physiological Characterization of Preserved Ratio Impaired Spirometry in the CanCOLD Study: Implications for Exertional Dyspnea and Exercise Intolerance

Rationale: It is increasingly recognized that adults with preserved ratio impaired spirometry (PRISm) are prone to increased morbidity. However, the underlying pathophysiological mechanisms are unknown. Objectives: Evaluate the mechanisms of increased dyspnea and reduced exercise capacity in PRISm. Methods: We completed a cross-sectional analysis of the CanCOLD (Canadian Cohort Obstructive Lung Disease) population-based study. We compared physiological responses in 59 participants meeting PRISm spirometric criteria (post-bronchodilator FEV1 < 80% predicted and FEV1/FVC ⩾ 0.7), 264 control participants, and 170 ever-smokers with chronic obstructive pulmonary disease (COPD), at rest and during cardiopulmonary exercise testing. Measurements and Main Results: Individuals with PRISm had lower total lung, vital, and inspiratory capacities than healthy controls (all P < 0.05) and minimal small airway, pulmonary gas exchange, and radiographic parenchymal lung abnormalities. Compared with healthy controls, individuals with PRISm had higher dyspnea/[Formula: see text]o2 ratio at peak exercise (4.0 ± 2.2 vs. 2.9 ± 1.9 Borg units/L/min; P < 0.001) and lower [Formula: see text]o2peak (74 ± 22% predicted vs. 96 ± 25% predicted; P < 0.001). At standardized submaximal work rates, individuals with PRISm had greater Vt/inspiratory capacity (Vt%IC; P < 0.001), reflecting inspiratory mechanical constraint. In contrast to participants with PRISm, those with COPD had characteristic small airways dysfunction, dynamic hyperinflation, and pulmonary gas exchange abnormalities. Despite these physiological differences among the three groups, the relationship between increasing dyspnea and Vt%IC during cardiopulmonary exercise testing was similar. Resting IC significantly correlated with [Formula: see text]o2peak (r = 0.65; P < 0.001) in the entire sample, even after adjusting for airflow limitation, gas trapping, and diffusing capacity. Conclusions: In individuals with PRISm, lower exercise capacity and higher exertional dyspnea than healthy controls were mainly explained by lower resting lung volumes and earlier onset of dynamic inspiratory mechanical constraints at relatively low work rates. Clinical trial registered with www.clinicaltrials.gov (NCT00920348).

Prevalence and Characteristics of Patients with Obstructive Sleep Apnea and Chronic Obstructive Pulmonary Disease: Overlap Syndrome

Overlap syndrome (OVS) is a distinct clinical entity that seems to result in potential cardiovascular consequences. We aimed to estimate the prevalence and risk factors for OVS in OSA patients and analyze clinical and PSG characteristics associated with OVS. In this cross-sectional study, 2616 patients evaluated for OSA underwent type-1 polysomnography (PSG). They were grouped as pure OSA (AHI > 15/h) and OVS patients. Demographics, PSG data, pulmonary function tests and arterial blood gases (ABGs) were compared between groups after adjustments for confounders. OSA was diagnosed in 2108 out of 2616 patients. Of those, 398 (19%) had OVS. Independent predictors of OVS were older age [OR: 5.386 (4.153-6.987)], current/former smoking [OR: 11.577 (7.232-18.532)], BMI [OR: 2.901 (2.082-4.044)] and ABG measurements [PaCO2 ≥ 45 OR: 4.648 (3.078-7.019), PO2 [OR: 0.934 (0.920-0.949)], HCO3- [OR: 1.196 (1.133-1.263), all p < 0.001]. OVS was also associated with prevalent hypertension [OR: 1.345 (1.030-1.758), p = 0.03] and cardiovascular disease [OR: 1.617 (1.229-2.126), p < 0.001], depressive symptoms [OR: 1.741 (1.230-2.465), p = 0.002] and nocturia [OR: 1.944 (1.378-2.742), p < 0.001], as well as with indices of OSA severity. Disturbances in sleep architecture were more prominent in OVS expressed by lower %N3 and REM% and higher arousal index. Our data suggest that OVS is prevalent among OSA patients, with distinct clinical and PSG characteristics. These characteristics could be utilized as predictive factors for early identification and further evaluation of these patients towards desirable patient-reported outcomes.

Sex and HIV Differences in Preserved Ratio Impaired Spirometry (PRISm) Among Ugandans Postpneumonia

Background

Preserved ratio impaired spirometry (PRISm), defined as a normal ratio of forced expiratory volume in 1 second (FEV1) to forced vital capacity (≥0.70) with low FEV1 (<80% predicted), has been associated with increased mortality in the general population. Female sex has been associated with increased odds of PRISm in people without HIV. People with HIV (PWH) are at increased risk for lung function abnormalities, but whether HIV modifies the effect of sex on PRISm development is largely unknown.

Methods

Adults with and without HIV underwent baseline followed by serial spirometry after completing therapy for pneumonia, predominantly tuberculosis (TB), in Kampala, Uganda. Using generalized estimating equations adjusted for age, body mass index, smoking, biomass fuel exposure, HIV, and TB status, we compared individuals with PRISm with those with normal spirometry. These models were stratified by HIV status.

Results

Of 339 baseline participants, 153 (45%) were women; 129 (38%) had HIV, of whom 53% were women. Overall, 105/339 participants (31%) had PRISm at baseline. HIV was associated with lower odds of PRISm (adjusted odds ratio [aOR], 0.38; 95% CI, 0.21-0.68; P = .001). Female sex trended toward increased odds of PRISm among all participants (aOR, 1.65; 95% CI, 0.99-2.75; P = .052). The association between female sex and PRISm tended to be stronger among PWH (aOR, 3.16; 95% CI, 1.14-8.76; P = .03) than among those without HIV (aOR, 1.34; 95% CI, 0.73-2.45; P = .34); this study was underpowered to detect an HIV-sex interaction of this magnitude (P = .30).

Conclusions

Among Ugandan adults who recovered from pneumonia, female sex was associated with increased odds and HIV with decreased odds of PRISm, suggesting independent sex and HIV effects on PRISm pathogenesis.

Potential pre-COPD indicators in association with COPD development and COPD prediction models in Chinese: a prospective cohort study

Background

Lung injury might take place before chronic obstructive pulmonary disease (COPD) occurs. A clearer definition of "pre-COPD" based on the effects of potential indicators on increasing risk of COPD development and a prediction model involving them are lacking.

Methods

A total of 3526 Chinese residents without COPD aged 40 years or older derived from the national cross-sectional survey of COPD surveillance in 2014-2015 were followed up for a mean of 3.59 years. We examined the associations of chronic bronchitis, preserved ratio impaired spirometry (PRISm), low peak expiratory flow (PEF), spirometric small airway dysfunction (sSAD), low maximal mid-expiratory flow (MMEF), low forced expiratory flow 50% of pulmonary volume (FEF50), and low FEF75 with subsequent COPD and constructed a prediction model with LASSO-Cox regression.

Findings

235 subjects in the cohort developed COPD during the follow-up. Subjects with PRISm, low PEF, sSAD, low MMEF, low FEF50, and low FEF75 had an increased risk of developing COPD (adjusted hazard ratio [HR] ranging from 1.57 to 3.01). Only chronic bronchitis (HR 2.84 [95% CI 1.38-5.84] and 2.94 [1.43-6.04]) and sSAD/low MMEF (HR 2.74 [2.07-3.61] and 2.38 [1.65-3.43]) showed effects independent of the other indicators and their concurrence had the strongest effect (HR 5.89 and 4.80). The prediction model including age, sex, low MMEF, low FEF50, and indoor exposure to biomass had good performance both internally and temporally. The corrected C-index was 0.77 (0.72-0.81) for discrimination in internal validation. For temporal validation, the area under the receiver operating characteristic curve was 0.73 (0.63-0.83). Good calibration was indicated in plot for internal validation and by Hosmer-Lemeshow test for temporal validation.

Interpretation

Individuals with concurrent chronic bronchitis and sSAD/low MMEF indicating pre-COPD optimally require more high attention from physicians. Our prediction model could serve as a multi-dimension tool to predict COPD comprehensively.

Funding

The Ministry of Finance and the Ministry of Science and Technology of the People's Republic of China and the National Natural Science Foundation of China.

Prevalence, characteristics and significant predictors for cardiovascular disease of patients with preserved ratio impaired spirometry: A 10-year prospective cohort study in China

BACKGROUND AND OBJECTIVE

Patients with preserved ratio impaired spirometry (PRIsm) have higher incidence rate of cardiovascular disease (CVD). However, few studies focused on PRIsm in China. We determined the prevalence and characteristics of patients with PRIsm in Chinese population. We also aimed to investigate the significant predictive factors of CVD in PRIsm patients.

METHODS

In total, 6994 subjects aged from 35 to 70 years old and free of CVD at baseline were categorized into normal (n = 3895), PRIsm (the ratio of forced expired volume in the first second (FEV1) to forced vital capacity (FVC) ≥0.7 and FEV1 <80 % predicted; n = 1997) and obstructive spirometry (FEV1:FVC<0.7; n = 1102). Cox proportional hazards multivariable regression was performed to investigate how baseline characteristics impact CVD incidence.

RESULTS

In participants with PRIsm, men had a 0.68-fold higher risk of CVD incidence than women (HR, 1.68; 95%CI, 1.09-2.59; p = 0.020). Our study showed that the rate of CVD incidence increased by 6.0 % with every year's increase in age (HR, 1.06; 95%CI, 1.04-1.09; p < 0.001). A 0.1 increase in FEV1/FVC was significantly associated with a 23.0 % decrease in CVD incidence (HR, 0.77; 95%CI, 0.61-0.97; p = 0.028). Family history of CVD greatly increased the risk of cardiovascular disease incidence (HR, 1.83; 95%CI, 1.18-2.83; p = 0.007). Higher BMI was also a significant risk factor of CVD incidence (HR, 1.06; 95%CI, 1.01-1.10; p = 0.013).

CONCLUSION

The prevalence of PRIsm in China was high. PRIsm subjects should be monitored carefully, especially for the older, male, those with higher BMI, lower FEV1/FVC and family history of CVD.

Individuals with psychosis present a reduced lung diffusion capacity and early spirometry alterations: Results from a cross-sectional study

OBJECTIVE

Individuals with psychosis present a greater prevalence of chronic lung diseases, including Chronic Obstructive Pulmonary Disease (COPD). These chronic respiratory diseases are preceded by early lung function alterations; such as preserved ratio impaired spirometry (PRISm) or normal spirometry but low diffusion capacity of the lung for carbon monoxide (DLCO). However, there is no previous evidence on these lung function alterations in psychosis. The aim of this study is to evaluate the risk of having spirometry and DLCO alterations in subjects with psychosis compared with a control group.

METHODS

Cross-sectional study on a cohort of 170 individuals including 96 subjects with psychosis and 74 sex-age-and smoking habit matched healthy controls. All subjects were under 60 years-old, and without COPD or asthma. Respiratory function was evaluated through spirometry. Clinical characteristics and DLCO values were recorded.

RESULTS

Patients with psychosis showed lower spirometry results, both in terms of absolute and percentage of Forced Vital Capacity (FVC) and Forced Expiratory Volume in one second (FEV1). Absolute and percentage levels of diffusion were also lower in patients with psychosis. The percentage of individuals with DLCO<80% was higher among patients with psychosis (75% vs. 40%, p < 0.001). And the prevalence of PRISm was higher among patients with psychosis (10.4% vs. 1.4%, p < 0.001). Multivariate logistic regression analysis indicated that psychosis was an independent predictor of DLCO<80% (OR 5.67, CI95% 1.86-17.27).

CONCLUSION

Patients with psychosis and females had early alterations in lung function. These results suggest that early screening for lung disease should be encouraged in psychosis.

The many faces of COPD in real life: a longitudinal analysis of the NOVELTY cohort

Background

The diagnosis of COPD requires the demonstration of non-fully reversible airflow limitation by spirometry in the appropriate clinical context. Yet, there are patients with symptoms and relevant exposures suggestive of COPD with either normal spirometry (pre-COPD) or preserved ratio but impaired spirometry (PRISm). Their prevalence, clinical characteristics and associated outcomes in a real-life setting are unclear.

Methods

To investigate them, we studied 3183 patients diagnosed with COPD by their attending physician included in the NOVELTY study (clinicaltrials.gov identifier NCT02760329), a global, 3-year, observational, real-life cohort that included patients recruited from both primary and specialist care clinics in 18 countries.

Results

We found that 1) approximately a quarter of patients diagnosed with (and treated for) COPD in real life did not fulfil the spirometric diagnostic criteria recommended by the Global Initiative for Chronic Obstructive Lung Disease (GOLD), and could be instead categorised as pre-COPD (13%) or PRISm (14%); 2) disease burden (symptoms and exacerbations) was highest in GOLD 3-4 patients (exacerbations per person-year (PPY) 0.82) and lower but similar in those in GOLD 1-2, pre-COPD and PRISm (exacerbations range 0.27-0.43 PPY); 3) lung function decline was highest in pre-COPD and GOLD 1-2, and much less pronounced in PRISm and GOLD 3-4; 4) PRISm and pre-COPD were not stable diagnostic categories and change substantially over time; and 5) all-cause mortality was highest in GOLD 3-4, lowest in pre-COPD, and intermediate and similar in GOLD 1-2 and PRISm.

Conclusions

Patients diagnosed COPD in a real-life clinical setting present great diversity in symptom burden, progression and survival, warranting medical attention.

Impact of preserved ratio impaired spirometry on coronary artery calcium score progression: a longitudinal cohort study

Background

Preserved ratio impaired spirometry (PRISm) is associated with increased cardiovascular disease (CVD) risk and mortality. However, a causal relationship between PRISm and CVD remains unclear. We investigated the progression of coronary artery calcium (CAC) scores based on the presence of PRISm and reduced forced vital capacity (FVC).

Methods

This retrospective cohort study included 11 420 participants aged ≥40 years with forced expiratory volume in 1 s (FEV1)/FVC ≥0.7 who underwent at least two health screening examinations with coronary computed tomography scan between 2003 and 2020, and were without a history of CVD or interstitial lung disease. Participants with PRISm, defined as FEV1/FVC ≥0.7 and FEV1 <80% predicted, were further divided by low FVC (FVC <80% predicted). We estimated the 5-year progression rates of CAC by comparing participants with and without PRISm at baseline using mixed linear models.

Results

Of the 11 420 participants, 8536 (75%), 811 (7%) and 2073 (18%) had normal spirometry, PRISm with normal FVC and PRISm with low FVC, respectively. During the mean (range) follow-up of 6.0 (0.5-17.2) years, the multivariable adjusted ratio of 5-year CAC progression rates comparing participants with PRISm to those with normal spirometry was 1.08 (95% CI 1.04-1.13). This rate was higher in participants with PRISm with low FVC (1.21 (95% CI 1.12-1.30)) than in those with normal FVC.

Conclusion

In this longitudinal cohort study of subjects without a history of CVD, PRISm was significantly associated with CAC progression, which was more evident in the group with PRISm and low FVC.

Roles of Inflammatory Biomarkers in Exhaled Breath Condensates in Respiratory Clinical Fields

BACKGROUND

Exhaled condensates contain inflammatory biomarkers; however, their roles in the clinical field have been under-investigated.

METHODS

We prospectively enrolled subjects admitted to pulmonology clinics. We collected exhaled breath condensates (EBC) and analysed the levels of six and 12 biomarkers using conventional and multiplex enzyme-linked immunosorbent assay, respectively.

RESULTS

Among the 123 subjects, healthy controls constituted the largest group (81 participants; 65.9%), followed by the preserved ratio impaired spirometry group (21 patients; 17.1%) and the chronic obstructive pulmonary disease (COPD) group (21 patients; 17.1%). In COPD patients, platelet derived growth factor-AA exhibited strong positive correlations with COPD assessment test (ρ=0.5926, p=0.0423) and COPD-specific version of St. George's Respiratory Questionnaire (SGRQ-C) score (total, ρ=0.6725, p=0.0166; activity, ρ=0.7176, p=0.0086; and impacts, ρ=0.6151, p=0.0333). Granzyme B showed strong positive correlations with SGRQ-C score (symptoms, ρ=0.6078, p=0.0360; and impacts, ρ=0.6007, p=0.0389). Interleukin 6 exhibited a strong positive correlation with SGRQ-C score (activity, ρ=0.4671, p=0.0378). The absolute serum eosinophil and basophil counts showed positive correlations with pro-collagen I alpha 1 (ρ=0.6735, p=0.0164 and ρ=0.6295, p=0.0283, respectively). In healthy subjects, forced expiratory volume in 1 second (FEV1)/forced vital capacity demonstrated significant correlation with CC chemokine ligand 3 (CCL3)/macrophage inflammatory protein 1 alpha (ρ=0.3897 and p=0.0068). FEV1 exhibited significant correlation with CCL11/eotaxin (ρ=0.4445 and p=0.0017).

CONCLUSION

Inflammatory biomarkers in EBC might be useful to predict quality of life concerning respiratory symptoms and serologic markers. Further studies are needed.

Longitudinal Changes and Association of Respiratory Symptoms with Preserved Ratio Impaired Spirometry (PRISm): The Nagahama Study

Rationale: Subjects with preserved ratio impaired spirometry (PRISm) experience increased respiratory symptoms, although they present heterogeneous characteristics. However, the longitudinal changes in these symptoms and respiratory function are not well known. Objectives: To investigate PRISm from the viewpoint of respiratory symptoms in a longitudinal, large-scale general population study. Methods: The Nagahama study included 9,789 inhabitants, and a follow-up evaluation was conducted after 5 years. Spirometry and self-administered questionnaires regarding respiratory symptoms, including prolonged cough, sputum and dyspnea, and comorbidities were conducted. Results: In total, 9,760 subjects were analyzed, and 438 subjects had PRISm. Among the subjects with PRISm, 53% presented with respiratory symptoms; dyspnea was independently associated with PRISm. Follow-up assessment revealed that 73% of the subjects with PRISm with respiratory symptoms were consistently symptomatic, whereas 39% of the asymptomatic subjects with PRISm developed respiratory symptoms within 5 years. In addition, among subjects with respiratory symptoms without airflow limitation at baseline, PRISm was a risk factor for the development of airflow limitation independent of smoking history and comorbidities. Conclusions: This study demonstrated that 53% of the subjects with PRISm had respiratory symptoms; dyspnea was a distinct characteristic of PRISm. Approximately three-fourths of the symptomatic subjects with PRISm consistently complained of respiratory symptoms within 5 years. Together with our result that PRISm itself is an independent risk factor for the development of chronic obstructive pulmonary disease among subjects with respiratory symptoms, the clinical course of subjects with PRISm with symptoms requires careful monitoring.

Effect of Broncho-Vaxom (OM-85) on the frequency of chronic obstructive pulmonary disease (COPD) exacerbations

BACKGROUND

Efforts have been made to reduce the risk of chronic obstructive pulmonary disease (COPD) exacerbations using a variety of measures. Broncho-Vaxom (BV) is an immunomodulating agent that has shown potential benefit by balancing between immune stimulation and regulation in patients with COPD. In this study, we evaluated the clinical efficacy of BV for reducing the risk of COPD exacerbations.

METHODS

This study was based on the Korean National Health Insurance database, which contains reimbursement information for almost the entire population of South Korea. We extracted data from 2016 to 2019 for patients started on BV during 2017-2018. We collected baseline data on demographics, comorbidities, inhaler use, hospital type, and insurance type 1 year before starting BV. We also analyzed exacerbation history, starting from the year before BV initiation.

RESULTS

In total, 238 patients were enrolled in this study. Their mean age was 69.2 ± 9.14 years, 79.8% were male, and 45% experienced at least one exacerbation. BV reduced the risk of moderate (odds ratio [OR] = 0.59, 95% confidence interval [CI]: 0.38-0.91) and moderate-to-severe exacerbations compared to pre- and post-BV (OR = 0.571, 95% CI: 0.37-0.89). BV use also reduced the incidence of moderate and moderate-to-severe exacerbations (incidence rate ratio [IRR] = 0.75, p = 0.03; and IRR = 0.77, p = 0.03, respectively). The use of BV was significantly delayed moderate exacerbations (hazard ratio = 0.68, p = 0.02), but not with moderate-to-severe or severe exacerbations.

CONCLUSION

The use of BV was associated with fewer moderate and moderate-to-severe exacerbations. Additionally, BV was associated with a delay in moderate COPD exacerbations.

Associations between environmental heavy metals exposure and preserved ratio impaired spirometry in the U.S. adults

We examined 9556 individuals aged 18 to 79 years who had information on spirometry testing and heavy metals and used multivariable logistic or linear regression to evaluate associations between serum levels of cadmium, lead, and mercury and PRISm and lung function in U.S. adults, which were conducted first in all participants, and then separately in never/former smokers and current smokers. The overall prevalence of PRISm was 7.02%. High levels of serum cadmium were significantly associated with PRISm in all individuals, no matter in never/former smokers (quartile 4 vs 1, the OR = 2.517, 95% CI = 1.376-4.604, p-trend = 0.0077) and current smokers (quartile 4 vs 1, the OR = 2.201, 95% CI = 1.265-3.830, p-trend = 0.0020). Serum lead and mercury were not significantly correlated with PRISm, regardless of smoking status. Serum cadmium was strongly correlated with lower FEV1/FVC, regardless of smoking status. Besides, serum cadmium was also significantly related to lower FVC % predicted in never/former smokers and lower FEV1% predicted in current smokers. Serum lead was strongly correlated with lower FVC % predicted and FEV1/FVC in all individuals and never/former smokers. And serum mercury was significantly associated with decrements in FVC % predicted in all individuals and current smokers. These findings demonstrate that serum cadmium is associated with a higher risk of PRISm and lower lung function, with the most significant effect on FEV1/FVC in particular. Our results also indicate that exposure to lead and mercury negatively affects lung function in never/former smokers and current smokers, respectively.

Clinical Use of an Exposure, Symptom, and Spirometry Algorithm to Stratify Smokers into COPD Risk Phenotypes: A Case Finding Study Combined with Smoking Cessation Counseling

Background

Chronic obstructive pulmonary disease (COPD) case-finding aims to detect airflow obstruction in symptomatic smokers and ex-smokers. We used a clinical algorithm including smoking, symptoms, and spirometry to classify smokers into COPD risk phenotypes. In addition, we evaluated the acceptability and effectiveness of including smoking cessation advice in the case-finding intervention.

Methods

Smoking, symptoms, and spirometry abnormalities (airflow obstruction: forced expiratory volume in 1 second [FEV1] to forced vital capacity [FVC] <0.7 or preserved-ratio spirometry (FEV1<80% of predicted value and FEV1/FVC ratio ≥ 0.7)] were assessed in a group of 864 smokers aged ≥ 30 years. The combination of these parameters allowed the identification of 4 phenotypes: Phenotype A (no symptoms, normal spirometry; reference), Phenotype B (symptoms; normal spirometry; possible COPD), Phenotype C (no symptoms; abnormal spirometry; possible COPD), and Phenotype D (symptoms; abnormal spirometry; probable COPD). We assessed phenotype differences in clinical variables and modeled the trend from phenotype A to phenotype D. Smoking cessation advice based on spirometry was provided. Follow-up was done by telephone 3 months later.

Results

Using smokers without symptoms or abnormal spirometry (phenotype A; n=212 [24.5%]) as a reference, smokers were classified into possible COPD (phenotype B;n=332 [38.4%]; and C: n=81 [9.4%]) and probable COPD (phenotype D: n=239 [27.2%]). The trend from baseline phenotype A to probable COPD phenotype D was significant for the number of cigarettes/day and the number of years of smoking (p=0.0001). At follow-up, 58 (7.7%) of the respondents (n=749) reported that they had quit smoking.

Conclusions

Our clinical algorithm allowed us to classify smokers into COPD phenotypes whose manifestations were associated with smoking intensity and to significantly increase the number of smokers screened for COPD. Smoking cessation advice was well accepted, resulting in a low but clinically significant quit rate.

Clinical Manifestations of Subjects With the Non-Specific Pulmonary Function Test Pattern

Introduction

Non-specific pattern (NSP) is a subgroup of preserved ratio impaired spirometry (PRISm) that requires a normal total lung capacity measurement. NSP has been historically classified as being an obstructive lung disease pattern. There has been heightened interest and investigation into PRISm recently as it has been associated with an increased likelihood of developing chronic obstructive pulmonary disease (COPD). Given the inherent challenges of understanding the clinical significance of the NSP, the aim of this study was to further explore the clinical characteristics of patients with this pulmonary function test pattern.

Material and methods

We identified 111 and 79 subjects using pre-bronchodilator (pre-BD) and post-bronchodilator (post-BD) values, respectively, that met criteria for NSP. The outpatient medical records were retrospectively reviewed for associated diagnoses that were then clustered into 'obstructive' or 'non-obstructive' groups based on the treating physician's primary pulmonary clinical diagnosis.

Results

Within this NSP cohort, cough, wheezing and sputum production were documented more frequently in those with an obstructive lung disease diagnosis. Whether identified using pre-BD or post-BD spirometric values, those with NSP and a positive BD response were more likely to carry an obstructive lung disease diagnosis.

Conclusion

Approximately one third of patients with NSP in this study were not given an obstructive lung disease diagnosis by their clinician, which supports the classification of NSP as not an exclusively obstructive lung disease pattern. However, the presence of supporting clinical symptoms, such as cough with sputum production and wheeze, and/or a positive BD response on PFT, support a diagnosis of obstruction in patients with NSP.

Longitudinal mortality of preserved ratio impaired spirometry in a middle-aged Asian cohort

BACKGROUND

Although preserved ratio impaired spirometry (PRISm) has been determined to have poor prognosis, it is a heterogeneous state, and studies regarding its prognosis in Asians are limited. This study investigated the long-term all-cause and cardiovascular mortality of patients with PRISm compared with those of patients with chronic obstructive pulmonary disease (COPD) and normal individuals in the Korean middle-aged general population.

METHODS

Participants were recruited between 2001 and 2002 from a community-based prospective cohort in South Korea. Mortality data were collected over a 16.5-year mean follow-up period. The all-cause and cardiovascular mortality risks of PRISm were compared between patients with COPD and healthy controls.

RESULTS

The PRISm group had a mean age of 53.4 years and mean body mass index of 24.9 kg/m²; furthermore, 55.2% of the PRISm patients had never smoked, and the prevalence of comorbidities was not higher than that in the other groups. Compared with normal individuals, PRISm patients did not show increased all-cause mortality, whereas COPD patients showed increased all-cause mortality (PRISm: adjusted hazard ratio [aHR], 1.19; 95% confidence interval [CI], 0.85-1.65; COPD: aHR, 1.34, 95% CI, 1.07-1.69). Furthermore, the PRISm patients did not show increased cardiovascular mortality compared with normal individuals (PRISm: aHR, 1.65; 95% CI, 0.92-2.95; COPD: aHR, 1.83; 95% CI, 1.09-3.07).

CONCLUSION

In our population-based cohort, all-cause and cardiovascular mortality risk did not increase in individuals with PRISm compared with normal individuals. Further studies are needed to distinguish a lower-risk subgroup of PRISm with certain characteristics, such as middle-aged, light-smoking Asians without additional cardiovascular risk.

Structural features on quantitative chest computed tomography of patients with maximal mid-expiratory flow impairment in a normal lung function population

BACKGROUND

Maximal mid-expiratory flow (MMEF) is an earlier predictor of chronic obstructive pulmonary disease (COPD) development than forced expiratory volume in 1 s (FEV₁). Changes of lung structure in patients with MMEF impairment only is still not clear. Therefore, this study aimed to investigate the structural features of patients with decreased MMEF by quantitative computed tomography (QCT) and develop a predictive model for predicting patients with reduced MMEF in normal lung function population.

METHODS

In this study, 131 patients with normal spirometry results and available volumetric chest CT images were enrolled and divided into the reduced MMEF group (FEV₁/forced expiratory vital capacity (FEV₁/FVC) > 0.7, FEV₁% predictive values (FEV₁%pred) > 80%, MMEF%pred < 80%, n = 52) and the normal MMEF group (FEV₁/FVC > 0.7, FEV₁%pred > 80%, MMEF%pred ≥ 80%, n = 79). The emphysema, small airway disease and medium-size airway parameters were measured by a commercial software. The differences were investigated in clinical features, spirometrical parameters and QCT parameters between the two groups. A nomogram model was constructed based on the results of the multivariable logistic regression model. Spearman's correlation coefficients were calculated between QCT measurements and spirometrical parameters.

RESULTS

There were more males in reduced MMEF group than normal group (P < 0.05). Lung parenchyma parameter (PRM^Emph) and airway-related parameters (functional small airway disease (PRM^fSAD), luminal area of fifth- and sixth- generation airway (LA₅, LA₆) were significantly different between the reduced MMEF group and the normal group (20.2 ± 17.4 vs 9.4 ± 6.7, 3.4 ± 3.5 vs 1.9 ± 2.0, 12.2 ± 2.5 vs 13.7 ± 3.4, 7.7 ± 2.4 vs 8.9 ± 2.8, respectively, all P < 0.01). After multivariable logistical regression, only sex (odds ratio [OR]: 2.777; 95% confidence interval [CI]:1.123-3.867), PRM^fSAD (OR:1.102, 95%CI:1.045-1.162) and LA₆ (OR:0.650, 95%CI:0.528-0.799) had significant differences between the two groups (P < 0.05) and a model incorporating with the three indicators was constructed (area under curve, 0.836). Correlation analysis showed MMEF%pred had mild to moderate correlation with airway-related measurements.

CONCLUSION

In normal lung function population, patients with reduced MMEF have potential medium-size and small airway changes, and MMEF%pred is significantly associated with airway-related CT parameters. The nomogram incorporating with sex, PRM^fSAD and LA₆ has good predictive value and offers more objective evidences in a group with reduced MMEF.

Preserved Ratio Impaired Spirometry in Relationship to Cardiovascular Outcomes: A Large Prospective Cohort Study

BACKGROUND

Preserved ratio impaired spirometry (PRISm) findings are a heterogeneous condition characterized by a normal FEV₁ to FVC ratio with underlying impairment of pulmonary function. Data relating to the association of baseline and trajectories of PRISm findings with diverse cardiovascular outcomes are sparse.

RESEARCH QUESTION

How do baseline and trajectories of PRISm findings impact subsequent cardiovascular events?

STUDY DESIGN AND METHODS

In the UK Biobank cohort study, we included participants free of cardiovascular disease (CVD) with spirometry (FEV₁ and FVC values) at baseline (2006-2010). Participants with baseline spirometry and follow-up spirometry (2014-2020) were included in the lung function trajectory analysis. Cox proportional hazards multivariate regression was performed to evaluate the outcomes of major adverse cardiovascular events (MACEs), incident myocardial infarction (MI), stroke, heart failure (HF), and CVD mortality in association with lung function.

RESULTS

For baseline analysis (329,954 participants), the multivariate adjusted hazard ratios (HRs) for participants had PRISm findings (vs normal spirometry findings) were 1.26 (95% CI, 1.17-1.35) for MACE, 1.12 (95% CI, 1.01-1.25) for MI, 1.88 (95% CI, 1.72-2.05) for HF, 1.26 (95% CI, 1.13-1.40) for stroke, and 1.55 (95% CI, 1.37-1.76) for CVD mortality, respectively. A total of 22,781 participants underwent follow-up spirometry after an average of 8.9 years. Trajectory analysis showed that persistent PRISm findings (HR, 1.96; 95% CI, 1.24-3.09) and airflow obstruction (HR, 1.43; 95% CI, 1.00-2.04) was associated with a higher incidence of MACE vs consistently normal lung function. Compared with persistent PRISm findings, changing from PRISm to normal spirometry findings was associated with a lower incidence of MACE (HR, 0.42; 95% CI, 0.19-0.99).

INTERPRETATION

Individuals with baseline or persistent PRISm findings were at a higher risk of diverse cardiovascular outcomes even after adjusting for a wide range of confounding factors. However, individuals who transitioned from PRISm to normal findings showed a similar cardiovascular risk as those with normal lung function.

Preserved ratio impaired spirometry with or without restrictive spirometric abnormality

Preserved ratio impaired spirometry (PRISm) is defined by reduced FEV₁ with a preserved FEV₁/FVC ratio; some individuals with PRISm can also have restrictive ventilatory abnormality. The aim of this study was to clarify clinical features of restrictive and non-restrictive PRISm. In total, 11,246 participants (mean, 49.1 years; range, 35-65 years) from five healthcare centres were included in this study. We evaluated baseline characteristics of participants with restrictive PRISm (FEV₁/FVC ≥ 0.7, FEV₁ < 80% and FVC < 80%) and non-restrictive PRISm (FEV₁/FVC ≥ 0.7, FEV₁ < 80% and FVC ≥ 80%), and airflow obstruction (FEV₁/FVC < 0.7). We examined the longitudinal risk of developing airflow obstruction by comparing spirometry results at baseline and 5 years post-baseline among 2141 participants. Multivariate analysis demonstrated that a history of asthma or smoking could constitute an independent risk factor for non-restrictive PRISm, and that non-restrictive PRISm was independently associated with the risk of developing airflow obstruction. In contrast, female sex, advanced age, and high BMI, but not history of asthma or smoking, were risk factors for restrictive PRISm. Restrictive PRISm was not associated with the development of airflow obstruction. In conclusion, our results indicate that PRISm can be categorized according to the presence or absence of restrictive abnormality. Non-restrictive PRISm, which does not meet the conventional criteria of obstructive and restrictive ventilatory abnormalities, may be a precursor of chronic obstructive pulmonary disease and merits increased monitoring.

Development of airflow limitation, dyspnoea, and both in the general population: the Nagahama study

Subjects with subclinical respiratory dysfunction who do not meet the chronic obstructive pulmonary disease (COPD) criteria have attracted attention with regard to early COPD intervention. Our aim was to longitudinally investigate the risks for the development of airflow limitation (AFL) and dyspnoea, the main characteristics of COPD, in a large-scale community-based general population study. The Nagahama study included 9789 inhabitants, and a follow-up evaluation was conducted after 5 years. AFL was diagnosed using a fixed ratio (forced expiratory volume in one second (FEV₁)/forced vital capacity (FVC) < 0.7). We enrolled normal subjects aged 40-75 years with no AFL, dyspnoea or prior diagnosis of asthma or COPD at baseline. In total, 5865 subjects were analysed, 310 subjects had subclinical respiratory dysfunction (FEV₁/FVC < the lower limit of normal; n = 57, and FEV₁ < 80% of the predicted value (preserved ratio impaired spirometry); n = 256). A total of 5086 subjects attended the follow-up assessment, and 449 and 1021 subjects developed AFL and dyspnoea, respectively. Of these, 100 subjects developed AFL with dyspnoea. Baseline subclinical respiratory dysfunction was independently and significantly associated with AFL with dyspnoea development within 5 years. Subjects with subclinical respiratory dysfunction are at risk of developing COPD-like features and require careful monitoring.

Clustering-based COPD subtypes have distinct longitudinal outcomes and multi-omics biomarkers

Introduction

Chronic obstructive pulmonary disease (COPD) can progress across several domains, complicating the identification of the determinants of disease progression. In our previous work, we applied k-means clustering to spirometric and chest radiological measures to identify four COPD-related subtypes: ‘relatively resistant smokers (RRS)’, ‘mild upper lobe-predominant emphysema (ULE)’, ‘airway-predominant disease (AD)’ and ‘severe emphysema (SE)’. In the current study, we examined the associations of these subtypes to longitudinal COPD-related health measures as well as blood transcriptomic and plasma proteomic biomarkers.

Methods

We included 8266 non-Hispanic white and African-American smokers from the COPDGene study. We used linear regression to investigate cluster associations to 5-year prospective changes in spirometric and radiological measures and to gene expression and protein levels. We used Cox-proportional hazard test to test for cluster associations to prospective exacerbations, comorbidities and mortality.

Results

The RRS, ULE, AD and SE clusters represented 39%, 15%, 26% and 20% of the studied cohort at baseline, respectively. The SE cluster had the greatest 5-year FEV₁ (forced expiratory volume in 1 s) and emphysema progression, and the highest risks of exacerbations, cardiovascular disease and mortality. The AD cluster had the highest diabetes risk. After adjustments, only the SE cluster had an elevated respiratory mortality risk, while the ULE, AD and SE clusters had elevated all-cause mortality risks. These clusters also demonstrated differential protein and gene expression biomarker associations, mostly related to inflammatory and immune processes.

Conclusion

COPD k-means subtypes demonstrate varying rates of disease progression, prospective comorbidities, mortality and associations to transcriptomic and proteomic biomarkers. These findings emphasise the clinical and biological relevance of these subtypes, which call for more study for translation into clinical practice.

Trail registration number

NCT00608764.

Prevalence and risk factors for COPD in subjects with preserved ratio impaired spirometry

BACKGROUND

Chronic obstructive pulmonary disease (COPD) has been found to be caused by impairment of lung development. Preserved ratio impaired spirometry (PRISm) is thought to be a subtype of lung growth impairment and is associated with COPD. PRISm is heterogeneous and the prevalence and progression to COPD are not yet clear. To prove this, we examined the association by using the medical check-up data.

METHODS

This retrospective study included medical check-up subjects who visited the Kochi Medical Check-up Clinic at least twice for both period 1 (P1) (2014-2016) for the first visit and period 2 (P2) (2017-2019) for the final visit. The mean duration between visits was 1042±323 days. COPD was defined as a forced expiratory volume in 1 s (FEV₁):forced vital capacity (FVC) ratio <lower limit of normal (LLN), and PRISm was defined as an FEV₁:FVC ratio >LLN and per cent forced expiratory volume in 1 s (%FEV₁) (FEV₁/predicted FEV₁) of <80% without bronchodilators in this study.

RESULTS

Of 1672 subjects (mean age±SD 56.5±9.5), 976 (58.4%) were male. The prevalence of PRISm was 10.5% in P1 and 8.9% in P2. The percentage of subjects who progressed to COPD was higher in PRISm than in the normal lung function group (OR 2.62, p=0.014). In logistic regression analysis, PRISm was an independent risk factor for developing COPD (OR 3.75, p<0.001). The best cut-off value of %FEV₁ for prediction of progression to COPD was 86%. The proportion of the PRISm group increased (23.6%) in this cut-off.

CONCLUSION

The prevalence of PRISm was around 10% but increased up to 23.6% at the best cut-off for progression to COPD, and careful follow-up is necessary in these groups even if FEV₁/FVC is normal.

Risks of Mortality and Airflow Limitation in Japanese with Preserved Ratio Impaired Spirometry

RATIONALE

Several Western studies have reported that participants with preserved ratio impaired spirometry (PRISm) have higher risks of airflow limitation (AFL) and death. However, evidence in East Asian populations is limited.

OBJECTIVES

To investigate the relation between PRISm and the risks of death and incident AFL in a Japanese population.

METHODS

A total of 3,032 community-dwelling Japanese participants aged ≥40 years were followed up for a median of 5.3 years by annual spirometry examinations. Participants were classified into lung function categories at baseline as follows: normal spirometry (forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) ≥0.70 and FEV1 ≥80% predicted), PRISm (≥0.70 and <80%), AFL Global Initiative for Chronic Obstructive Lung Disease (GOLD) 1 (<0.70 and ≥80%), and AFL GOLD 2-4 (<0.70 and <80%). Hazard ratios (HRs) and their 95% confidence intervals (CIs) were computed using a Cox proportional hazard model.

MEASUREMENTS AND MAIN RESULTS

During the follow-up period, 131 participants died, 22 of whom died from cardiovascular disease, and 218 participants developed AFL. When examining the prognosis of each baseline pulmonary function category, participants with PRISm had higher risks of all-cause death (HR 2.20 [95%CI: 1.35 to 3.59]) and cardiovascular death (HR 4.07 [1.07 to 15.42]) than those with normal spirometry after adjusting for confounders. Moreover, the multivariable-adjusted risk of incident AFL was greater in participants with PRISm than in those with normal spirometry (HR 2.48 [1.83 to 3.36]).

CONCLUSIONS

PRISm was associated with higher risks of all-cause and cardiovascular death and a greater risk of the development of AFL in a Japanese community.

Prevalence, risk factors, and clinical implications of preserved ratio impaired spirometry: a UK Biobank cohort analysis

BACKGROUND

Preserved ratio impaired spirometry (PRISm) is defined as a FEV1 of less than 80% predicted and a FEV1/forced vital capacity (FVC) ratio of 0·70 or higher. Previous research has indicated that PRISm is associated with respiratory symptoms and is a precursor of chronic obstructive pulmonary disease (COPD). However, these findings are based on relatively small selective cohorts with short follow-up. We aimed to determine the prevalence, risk factors, clinical implications, and mortality of PRISm in a large adult general population.

METHODS

For this cohort analysis, we used data from the UKBiobank to assess PRISm prevalence, risk factors and associated symptoms, and associated comorbidities in a large adult population. Participants with spirometry deemed acceptable by an investigator (best measure FEV1 and FVC values) at baseline were included. Participants were excluded if they did not have acceptable spirometry or were missing data on body-mass index or smoking status. Control spirometry was defined as a FEV1 of 80% or more predicted and a FEV1/FVC ratio of 0·70 or higher. Airflow obstruction was defined as a FEV1/FVC ratio of less than 0·70. We used multivariable regression to determine risk factors for PRISm and associated comorbidities. Individuals who lived within close proximity to an assessment centre were invited for follow-up, with repeat spirometry. Only participants who had been included at baseline were examined in follow-up. This allowed for a longitudinal analysis of PRISm over time and risk factors for transition to airflow obstruction. We also did the survival analysis for a 12-year period.

FINDINGS

Participants were recruited by UK Biobank between Dec 19, 2006, and Oct 10, 2010. We included 351 874 UK Biobank participants (189 247 women and 162 627 men) in our study, with a median follow-up of 9·0 years (IQR 8·0-10·0). 38 639 (11·0%) of 351 874 participants had PRISm at baseline. After adjustment, PRISm was strongly associated with obesity (odds ratio [OR] 2·40 [2·26-2·55], p<0·0001), current smoking (1·48 [1·36-1·62], p<0·0001), and patient reported doctor-diagnosed asthma (1·76 [1·66-1·88], p<0·0001). Other risk factors identified included female sex, being overweight, trunk fat mass, and trunk fat percentage. PRISm was strongly associated with symptoms and comorbidity including increased risk of breathlessness (adjusted OR 2·0 [95% CI 1·91-2·14], p<0·0001) and cardiovascular disease (adjusted OR 1·71 [1·64-1·83], p<0·0001 for heart attack). Longitudinal analysis showed that 241 (12·2%) of 1973 participants who had PRISm at baseline had transitioned to airflow obstruction consistent with COPD. PRISm was associated with increased all-cause mortality (adjusted hazard ratio 1·61 [95% CI 1·53-1·69], p<0·0001) versus control participants.

INTERPRETATION

PRISm was associated with breathlessness, multimorbidity, and increased risk of death, which does not seem to be explained by smoking, obesity, or existing lung disease. Although for many patients PRISm is transient, it is important to understand which individuals are at risk of progressive lung function abnormalities. Further research into the genetic, structural and functional pathophysiology of PRISm is warranted.

FUNDING

UK Medical Research Council and University of Bristol.

Different Risks of Mortality and Longitudinal Transition Trajectories in New Potential Subtypes of the Preserved Ratio Impaired Spirometry: Evidence From the English Longitudinal Study of Aging

Background: Preserved ratio impaired spirometry (PRISm), characterized by the decreased forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC) with a preserved FEV₁/FVC ratio, is highly prevalent and heterogeneous. We aimed to identify the subtypes of PRISm and examine their differences in clinical characteristics, long-term mortality risks, and longitudinal transition trajectories.

Methods: A total of 6,616 eligible subjects were included from the English longitudinal study of aging. Two subtypes of the PRISm were identified as mild PRISm (either of FEV₁ and FVC <80% predicted value, FEV₁/FVC ≥0.7) and severe PRISm (both FEV₁ and FVC <80% predicted values, FEV₁/FVC ≥0.7). Normal spirometry was defined as both FEV₁ and FVC ≥80% predicted values and FEV₁/FVC ≥0.7. Hazard ratios (HRs) and 95% CIs were calculated by the multiple Cox regression models. Longitudinal transition trajectories were described with repeated spirometry data.

Results: At baseline, severe PRISm had increased respiratory symptoms, including higher percentages of phlegm, wheezing, dyspnea, chronic bronchitis, and emphysema than mild PRISm. After an average of 7.7 years of follow-up, severe PRISm significantly increased the risks of all-cause mortality (HR=1.91, 95%CI = 1.58–2.31), respiratory mortality (HR = 6.02, 95%CI = 2.83–12.84), and CVD mortality (HR = 2.11, 95%CI = 1.42–3.13) compared with the normal spirometry, but no significantly increased risks were found for mild PRISm. In the two longitudinal transitions, mild PRISm tended to transition toward normal spirometry (40.2 and 54.7%), but severe PRISm tended to maintain the status (42.4 and 30.4%) or transition toward Global Initiative for Chronic Obstructive Lung Disease (GOLD)2–4 (28.3 and 33.9%).

Conclusion: Two subtypes of PRISm were identified. Severe PRISm had increased respiratory symptoms, higher mortality risks, and a higher probability of progressing to GOLD2–4 than mild PRISm. These findings provided new evidence for the stratified management of PRISm.

Prevalence and Characteristics of Individuals with Preserved Ratio Impaired Spirometry (PRISm) and/or Impaired Lung Function in Japan: The OCEAN Study

Purpose

Many individuals with obstructive airway disease (OAD), including chronic obstructive pulmonary disease (COPD) and asthma, remain undiagnosed, despite the potential for reducing disease burden through early detection and treatment. OCEAN aimed to determine the prevalence of, and characteristics associated with, impaired lung function in a Japanese population, with the goal of improving strategies for early OAD detection.

Methods

OCEAN was an observational, cross-sectional study in sequentially recruited Japanese individuals ≥40 years of age undergoing routine health examinations. Participants completed screening questionnaires and spirometry testing. Airflow limitation was defined as forced expiratory volume in 1 second/forced vital capacity (FEV₁/FVC) <0.7 by pre-bronchodilator spirometry. Preserved ratio impaired spirometry (PRISm) was defined as FEV₁/FVC ≥0.7 and FEV₁ <80% predicted. The primary endpoint was prevalence of spirometry-based airflow limitation and PRISm. The characteristics of study participants were reported as secondary endpoints.

Results

Overall, 2518 individuals were included; 79% were <60 years of age (mean 52.0 years). Airflow limitation and PRISm were observed in 52 (2.1%) and 420 (16.7%) participants, respectively. FEV₁ in the PRISm group was between that in the no airflow limitation/PRISm and airflow limitation groups, FVC was similar in the PRISm and airflow limitation groups. The PRISm group had higher mean body mass index and a higher proportion of comorbid metabolic disease compared with the airflow limitation group. The prevalence of airflow limitation and PRISm was highest among current smokers (3.9% and 21.3%, respectively) versus former or never smokers.

Conclusion

A significant proportion of Japanese individuals <60 years of age attending their annual health examination had impaired lung function (airflow limitation and PRISm); prevalence was highest among current smokers. These findings support screening of current or former smokers ≥40 years of age using patient-reported questionnaires to inform the need for spirometry to confirm an OAD diagnosis.

Physical performance in relation to preserved ratio impaired spirometry: a cross-sectional study of community-dwelling older Japanese adults

Preserved ratio impaired spirometry (PRISm) is associated with an increased mortality rate; however, its characteristics have not been clearly identified in Japan. This cross-sectional study of community-dwelling older adults compared physical function between people with PRISm and those with no respiratory issues, from 2014 to 2019. We collected demographic data through interviews and measured respiratory and physical functions. We included 668 older adults (male, 23.5%; mean age, 72.8 ± 5.6 years); the prevalence of PRISm was 12%, while the prevalence of obstruction was 6.9%. Propensity score matching was used to identify control subjects with normal spirometry (n = 80) while minimizing the effects of confounders during comparisons with the PRISm population (n = 80). Compared with community-dwelling older adults with normal lung capacity, older adults with PRISm had a lower forced vital capacity (%FVC; 68.7 ± 9.1% vs. 92.5 ± 12.7%, p < 0.001), lower core muscle endurance (sit-up test: 6.7 ± 5.8 vs. 8.7 ± 6.0, p = 0.032), and a longer one-leg stance duration (52.4 ± 41.1 s vs. 36.4 ± 34.1 s, p = 0.008). In multivariable logistic regression, %FVC and increased one-leg stance were independent predictors of PRISm status. The prevalence of PRISm among community-dwelling elderly Japanese exceeds that of obstructive lung disease and is associated with reduced %FVC and better performance on balance testing.

Association between Comorbidities and Preserved Ratio Impaired Spirometry: Using the Korean National Health and Nutrition Examination Survey IV-VI

BACKGROUND

Preserved ratio impaired spirometry (PRISm) patients have more frequent respiratory symptoms and an increased risk of mortality. However, studies on comorbidities in these patients are lacking.

OBJECTIVES

We investigated the association between PRISm and comorbidities using the Korea National Health and Nutrition Examination Survey (KNHANES).

METHOD

This cross-sectional study included participants aged ≥50 years from the KNHANES (2007-2015). Participants who did not undergo spirometry or performed inadequately were excluded. We classified participants into 3 groups according to spirometry: PRISm (forced expiratory volume in one second [FEV1] /forced vital capacity [FVC] ≥ 0.7 and FEV1 <80%), chronic obstructive pulmonary disease (COPD) (FEV1/ FVC <0.7), and normal. Multivariate logistic regression analyses were used to evaluate the risk of comorbidities in the PRISm group compared to that in the normal group.

RESULT

The study included 17,515 participants: 12,777 (73.0%), 1,563 (8.9%), and 3,175 (18.1%) in normal, PRISm, and COPD groups, respectively. After adjustment for known risk factors of each disease, hypertension (adjusted odds ratio [95% confidence interval]; 1.31 [1.14-1.50]), diabetes (1.51 [1.29-1.78]), hypercholesterolemia (1.20 [1.04-1.37]), obesity (1.31 [1.15-1.48]), ischemic heart disease (1.58 [1.13-2.22]), chronic renal disease (2.31 [1.09-4.88]), and thyroid disease (1.41 [1.09-1.83]) risks were significantly higher in the PRISm group than in the normal group. The average number of comorbidities was 2.45 in the PRISm group, which was higher than that in the normal (2.1) and COPD (2.03) groups (p < 0.05).

CONCLUSION

The number of comorbidities was significantly higher in the PRISm group than in others. Hypertension, diabetes, obesity, ischemic heart disease, chronic renal disease, and thyroid disease were associated with PRISm after adjustment for risk factors.

The current status of chronic obstructive pulmonary disease awareness, treatments, and plans for improvement in South Korea: a narrative review

The prevalence of chronic obstructive pulmonary disease (COPD) is high in South Korea which has remained virtually unchanged over the past few years. Other challenges related to COPD in South Korea include a low level of awareness of COPD, underutilization of pulmonary function tests (PFTs) and a low level of inhaler use. Continued efforts have been made to raise awareness of COPD in the general public and promote screening tests for the early detection of COPD patients for high-risk patients, which should be the primary object for better management of the disease. The Korean Academy of Tuberculosis and Respiratory Diseases (KATRD) and the Korea Disease Control and Prevention Agency (KDCA) have been working in tandem on numerous projects to resolve these issues. As the fruit of these efforts, a couple of projects are currently being carried out to add PFTs into the National Health Examination (NHE) of Korea as part of screening tests and improve the quality of COPD treatments in primary care settings. Raising public awareness of a chronic disease such as COPD requires collective efforts of academic societies and government. In addition, personalized education programs that are tailored to individual COPD patients is a necessity to raise adherence of treatment and self-management of COPD. The aim of this manuscript is to report the current status of COPD management in South Korea in hopes that it will help better treat and manage COPD in other nations coping with similar challenges.

FEF25-75% Values in Patients with Normal Lung Function Can Predict the Development of Chronic Obstructive Pulmonary Disease

Purpose

The forced mid-expiratory flow (FEF_25-75%) value is a potentially sensitive marker of obstructive peripheral airflow. We aimed to assess whether FEF_25-75% can be an early predictor of chronic obstructive pulmonary disease (COPD).

Patients and Methods

Between July 1, 2007 and June 31, 2009, we identified 3624 patients who underwent a pulmonary function test (PFT) in Gangnam Severance Hospital. We selected 307 patients aged over 40 years without COPD who had normal PFT results at baseline and who had follow-up PFT records more than 1 year later. A FEF_25-75% z-score less than −0.8435 was considered low. We defined COPD as a forced expiratory volume in one second/forced vital capacity value of less than 0.7 before July 31, 2019.

Results

Among 307 patients, 91 (29.6%) had low FEF_25-75% at baseline. After 10 years, the incidence rate of COPD in the low FEF_25-75% group was significantly higher than that in the normal FEF_25-75% group (41.8% vs 7.4%; P-value<0.001). The Cox proportional hazard model showed that age (hazard ratio [HR] 1.09; P-value<0.001), smoking status (occasional smoker HR, 4.59; P-value<0.001 and long-term smoker HR, 2.18; P-value=0.023), and low FEF_25-75% (HR, 3.31; P-value<0.001) were predictive factors for the development of COPD.

Conclusion

The FEF_25-75% value in patients with normal lung function is a useful predictor for the development of COPD. We should carefully monitor patients who present with low FEF_25-75% values, even if they have normal lung function.

Frequent Outpatient Visits Prevent Exacerbation of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory airway disease requiring frequent outpatient visits and lifelong management. We aimed to evaluate the roles of frequent outpatient visits in prognosis of COPD. We used claims data in the national medical insurance review system provided by the Health Insurance Review and Assessment Service of Korea from May 1, 2014 to April 30, 2015. A definition of COPD was used based on the diagnosis code and medication. Frequent visitors were defined as subjects who visited the outpatient clinic for COPD three or more times per year. Among 159,025 subjects, 117,483 (73.9%) were classified as frequent visitors. Frequent visitors underwent pulmonary function tests and used various inhalers more often than did infrequent visitors. The rates of COPD exacerbation requiring admission to a general ward, emergency room, or intensive care unit were significantly lower in frequent visitors than in infrequent visitors. In multivariable analysis, frequent visits were identified as an independent factor preventing COPD exacerbation that required admission to a ward (odds ratio [OR], 0.387), emergency room, (OR, 0.558), or intensive care unit (OR, 0.39) (all P < 0.001). In conclusion, we showed frequent outpatient visits reduce the risk of COPD exacerbation by 45-60%.

Trajectory and mortality of preserved ratio impaired spirometry: the Rotterdam Study

Preserved ratio impaired spirometry (PRISm) is a heterogeneous condition but its course and disease progression remain to be elucidated. We aimed to examine its prevalence, trajectories and prognosis in the general population.In the Rotterdam Study (population-based prospective cohort) we examined prevalence, trajectories and prognosis of subjects with normal spirometry (controls; forced expiratory volume in 1 s (FEV₁)/forced vital capacity (FVC) ≥0.7, FEV₁  ≥80%), PRISm (FEV₁/FVC ≥0.7, FEV₁ <80%) and chronic obstructive pulmonary disease (COPD) (FEV₁/FVC <0.7) at two study visits. Hazard ratios with 95% confidence intervals for mortality (until December 30, 2018) were adjusted for age, sex, body mass index, current smoking and pack-years.Of 5487 subjects (age 69.1±8.9 years; 7.1% PRISm), 1603 were re-examined after 4.5 years. Of the re-examined PRISm subjects, 15.7% transitioned to normal spirometry and 49.4% to COPD. Median lung function decline was highest in subjects with incident PRISm (FEV₁ -92.8 mL·year^-1, interquartile range (IQR) -131.9- -65.8 mL·year^-1; FVC -93.3 mL·year^-1, IQR -159.8- -49.1 mL·year^-1), but similar in persistent PRISm (FEV₁ -30.2 mL·year^-1, IQR -67.9- -7.5 mL·year^-1; FVC -20.1 mL·year^-1, IQR -47.7-21.7 mL·year^-1) and persistent controls (FEV₁ -39.6 mL·year^-1, IQR -64.3--12.7 mL·year^-1; FVC -20.0 mL·year^-1, IQR -55.4-18.8 mL·year^-1). Of 5459 subjects with informed consent for follow-up, 692 (12.7%) died during 9.3 years (maximum) follow-up: 10.3% of controls, 18.7% of PRISm subjects and 20.8% of COPD subjects. Relative to controls, subjects with PRISm and COPD Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2-4 had increased all-cause mortality (PRISm: HR 1.6, 95% CI 1.2-2.0; COPD GOLD 2-4: HR 1.7, 95% CI 1.4-2.1) and cardiovascular mortality (PRISm: HR 2.8, 95% CI 1.5-5.1; COPD 2-4: HR 2.1, 95% CI 1.2-3.6). Mortality within <1 year was highest in PRISm, with patients often having cardiovascular comorbidities (heart failure or coronary heart disease; 70.0%).PRISm is associated with increased mortality and this population encompasses at least three distinct subsets: one that develops COPD during follow-up, a second with high cardiovascular burden and early mortality, and a third with persistent PRISm and normal age-related lung function decline.

NR, Make BJ, Marchetti N, Martinez FJ, Maselli DJ, Mathews AM, McCormack MC, McDonald MLN, McEvoy CE, Moll M, Molye SS, Murray S, Nath H, Newell Jr. JD, Occhipinti M, Paoletti M, Parekh T, Pistolesi M, Pratte KA, Putcha N, Ragland M, Reinhardt JM, Rennard SI, Rosiello RA, Ross JC, Rossiter HB, Ruczinski I, San Jose Estepar R, Sciurba FC, Sieren JC, Singh H, Soler X, Steiner RM, Strand MJ, Stringer WW, Tal-Singer R, Thomashow B, Vegas Sánchez-Ferrero G, Walsh JW, Wan ES, Washko GR, Michael Wells J, Wendt CH, Westney G, Wilson A, Wise RA, Yen A, Young K, Yun J, Silverman EK, Crapo JD. COPDGene® 2019: Redefining the Diagnosis of Chronic Obstructive Pulmonary Disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) remains a major cause of morbidity and mortality. Present-day diagnostic criteria are largely based solely on spirometric criteria. Accumulating evidence has identified a substantial number of individuals without spirometric evidence of COPD who suffer from respiratory symptoms and/or increased morbidity and mortality. There is a clear need for an expanded definition of COPD that is linked to physiologic, structural (computed tomography [CT]) and clinical evidence of disease. Using data from the COPD Genetic Epidemiology study (COPDGene®), we hypothesized that an integrated approach that includes environmental exposure, clinical symptoms, chest CT imaging and spirometry better defines disease and captures the likelihood of progression of respiratory obstruction and mortality.

METHODS

Four key disease characteristics - environmental exposure (cigarette smoking), clinical symptoms (dyspnea and/or chronic bronchitis), chest CT imaging abnormalities (emphysema, gas trapping and/or airway wall thickening), and abnormal spirometry - were evaluated in a group of 8784 current and former smokers who were participants in COPDGene® Phase 1. Using these 4 disease characteristics, 8 categories of participants were identified and evaluated for odds of spirometric disease progression (FEV1 > 350 ml loss over 5 years), and the hazard ratio for all-cause mortality was examined.

RESULTS

Using smokers without symptoms, CT imaging abnormalities or airflow obstruction as the reference population, individuals were classified as Possible COPD, Probable COPD and Definite COPD. Current Global initiative for obstructive Lung Disease (GOLD) criteria would diagnose 4062 (46%) of the 8784 study participants with COPD. The proposed COPDGene® 2019 diagnostic criteria would add an additional 3144 participants. Under the new criteria, 82% of the 8784 study participants would be diagnosed with Possible, Probable or Definite COPD. These COPD groups showed increased risk of disease progression and mortality. Mortality increased in patients as the number of their COPD characteristics increased, with a maximum hazard ratio for all cause-mortality of 5.18 (95% confidence interval [CI]: 4.15-6.48) in those with all 4 disease characteristics.

CONCLUSIONS

A substantial portion of smokers with respiratory symptoms and imaging abnormalities do not manifest spirometric obstruction as defined by population normals. These individuals are at significant risk of death and spirometric disease progression. We propose to redefine the diagnosis of COPD through an integrated approach using environmental exposure, clinical symptoms, CT imaging and spirometric criteria. These expanded criteria offer the potential to stimulate both current and future interventions that could slow or halt disease progression in patients before disability or irreversible lung structural changes develop.

Spirometric indices of early airflow impairment in individuals at risk of developing COPD: Spirometry beyond FEV1/FVC

Spirometry is the current gold standard for diagnosing and monitoring the progression of Chronic Obstructive Pulmonary Disease (COPD). However, many current and former smokers who do not meet established spirometric criteria for the diagnosis of this disease have symptoms and clinical courses similar to those with diagnosed COPD. Large longitudinal observational studies following individuals at risk of developing COPD offer us additional insight into spirometric patterns of disease development and progression. Analysis of forced expiratory maneuver changes over time may allow us to better understand early changes predictive of progressive disease. This review discusses the theoretical ability of spirometry to capture fine pathophysiologic changes in early airway disease, highlights the shortcomings of current diagnostic criteria, and reviews existing evidence for spirometric measures which may be used to better detect early airflow impairment.