Project description:BackgroundGuidelines advocate pulmonary function testing (PFT) in preoperative evaluation before lung resection. Although forced expiratory volume in 1 s (FEV1) and diffusing capacity of the lungs for carbon monoxide (DLCO) are recommended, they are often poor predictors of complications.ObjectivesDetermine if PFT testing results other than FEV1 and DLCO are associated with post-operative complications. We hypothesized that other PFT test results may improve the prediction of post-operative complications.DesignRetrospective cohort study of a single institution.MethodsWe analyzed patients who underwent anatomic lung resections from 1/2007 to 1/2017. Percent predicted post-operative (ppo) PFT values were calculated for each test result. Outcome of interest was any post-operative complication. Wilcoxon rank-sum and multivariable regression were used to determine the relationship of PFT results to post-operative complications.ResultsWe analyzed 922 patients who underwent anatomic lung resections. Complications occurred in 240 (26.0%) patients, and mortality occurred in 12 (1.3%) patients. In univariate analysis, predicted and percent predicted post-operative (ppo) forced vital capacity (FVC), FEV1, FEF2575, DLCO, DLCO/VA, and VC values were predictors of post-operative complications. Multivariable logistic regression found no independent relationship of test results to post-operative complications, likely reflecting the collinearity of PFT results.ConclusionOur findings suggest that non-traditional PFTs, such as FVC, may enhance risk stratification for post-operative complications following anatomic lung resection. Notably, traditional parameters like FEV1 and DLCO were not independently predictive, highlighting the need to reconsider their role in isolation. These findings highlight the need to reconsider how PFT are used in surgical risk stratification given high levels of collinearity.
Project description:Introduction: Typical symptoms of chronic obstructive pulmonary disease (COPD) include breathlessness and reduced exercise capacity. Several laboratory- and field-based exercise tests are used to assess the exercise capacity of patients with COPD. It is unclear whether these exercise tests reflect the spirometric measures recommended for diagnosis of COPD. We therefore aimed to systematically assess the correlation between these exercise tests and common measures of lung function. Methods: A search of Embase™, MEDLINE® and The Cochrane Library identified primary publications in English that reported data on the correlations (Pearson's r or Spearman's rho) between the outcomes of exercise tests and the physiological measures of interest: forced expiratory volume in 1 second (FEV1), forced vital capacity, inspiratory capacity and arterial oxygen saturation. We included studies reporting on the following exercise tests: 6- and 12-minute walk tests (6MWT and 12 MWT), incremental and endurance shuttle walk tests, incremental and endurance cycle ergometer tests, and treadmill tests. Results: Of 1781 articles screened, 45 were ultimately deemed eligible for inclusion in this review. The most commonly reported lung function variable was FEV1 (reported by 39 studies); the most commonly reported exercise test was the 6-minute walk test (reported by 24 studies). FEV1 appears to correlate moderately-to-strongly with 6MWT and 12MWT; and moderately-to-very strongly with incremental cycle ergometer tests (ICET); evidence for other exercise tests was limited. Conclusion: There is evidence that 6MWT, 12MWT and ICET correlate with FEV1 to some degree; - evidence for associations of other exercise tests with measures of lung function in patients with COPD is limited. Clinicians must consider this when deciding to use these tests. Further comparisons of these tests must be made in order to assess which physiological and hemodynamic characteristics they reflect in patients with COPD.
Project description:BackgroundIn advanced chronic obstructive pulmonary disease (COPD), hypercapnia may occur due to severe bronchial obstruction with lung hyperinflation. Non-invasive ventilation (NIV) provides the standard of care intended to achieve physiological PCO2 levels, thereby reducing overall mortality. The present study aimed to evaluate pulmonary function parameters derived from spirometry (forced vital capacity [FVC], forced expiratory volume in 1 s [FEV1]), body plethysmography (residual volume [RV], total lung capacity [TLC]), and lung diffusion capacity for carbon monoxide (single-breath method [DCO-SB], alveolar-volume corrected values [DCO-VA]) as predictors of chronic hypercapnia in patients with advanced COPD.MethodsThis monocentric, retrospective observational study included 423 COPD patients. Receiver operating characteristic (ROC) curve analysis and cross-validation were used to assess lung function parameters' diagnostic accuracy for predicting chronic hypercapnia, with the resulting performance expressed as area under the ROC curve (AUROC). We performed univariable and multivariable binary logistic regression analysis to determine if these parameters were independently associated with chronic hypercapnia, with probabilities reported as odds ratios [OR] with 95% confidence intervals [95%CI].ResultsFVC% (AUROC 0.77 [95%CI 0.72-0.81], P < 0.01) and FEV1% (AURIC 0.75 [95%CI 0.70-0.79], P < 0.01) exhibited reasonable accuracy in the prediction of chronic hypercapnia, whereas lung diffusion capacity performed poorly (AUROC 0.64 [95%CI 0.58-0.71] for DCO-SB%, P < 0.01). FVC% (OR 0.95 [95%CI 0.93-0.97], P < 0.01) and FEV1% (OR 0.97 [95%CI 0.94-0.99], P = 0.029) were the only parameters associated independently with chronic hypercapnia in logistic regression analysis. FVC and FEV1 thresholds that best separated hypercapnic from normocapnic subjects reached 56% and 33% of predicted values.ConclusionsRoutinely collected pulmonary function parameters, particularly FVC% and FEV1%, may predict chronic hypercapnia during COPD progression.
Project description:Background and purposeRadiation-induced lung damage (RILD) is a common consequence of lung cancer radiotherapy (RT) with unclear evolution over time. We quantify radiological RILD longitudinally and correlate it with dosimetry and respiratory morbidity.Materials and methodsCTs were available pre-RT and at 3, 6, 12 and 24-months post-RT for forty-five subjects enrolled in a phase 1/2 clinical trial of isotoxic, dose-escalated chemoradiotherapy for locally advanced non-small cell lung cancer. Fifteen CT-based measures of parenchymal, pleural and lung volume change, and anatomical distortions, were calculated. Respiratory morbidity was assessed with the Medical Research Council (MRC) dyspnoea score and spirometric pulmonary function tests (PFTs): FVC, FEV1, FEV1/FVC and DLCO.ResultsFEV1, FEV1/FVC and MRC scores progressively declined post-RT; FVC decreased by 6-months before partially recovering. Radiologically, an early phase (3-6 months) of acute inflammation was characterised by reversible parenchymal change and non-progressive anatomical distortion. A phase of chronic scarring followed (6-24 months) with irreversible parenchymal change, progressive volume loss and anatomical distortion. Post-RT increase in contralateral lung volume was common. Normal lung volume shrinkage correlated longitudinally with mean lung dose (r = 0.30-0.40, p = 0.01-0.04). Radiological findings allowed separation of patients with predominant acute versus chronic RILD; subjects with predominantly chronic RILD had poorer pre-RT lung function.ConclusionsCT-based measures enable detailed quantification of the longitudinal evolution of RILD. The majority of patients developed progressive lung damage, even when the early phase was absent or mild. Pre-RT lung function and RT dosimetry may allow to identify subjects at increased risk of RILD.
Project description:BackgroundTuberculosis (TB) remains a major threat to human health, and TB diagnostic methods remain unsatisfactory. Nucleic acid amplification tests (NAATs) show higher sensitivity compared with culture for the diagnosis of pulmonary TB (PTB). However, NAATs are expensive and cannot be easily implemented outside major medical centers. To improve the sensitivity of NAATs for PTB diagnosis, we investigated the predictive factors that might optimize NAAT utilization.MethodsA total of 1263 patients with suspected PTB were enrolled for evaluation. The sensitivity, specificity, and accuracy of methods including smear-microbiology, culture of Mtb and NAAT for Mycobacterium tuberculosis (Mtb) detection in sputum and bronchoalveolar lavage fluid samples were compared. Odds ratios and 95% confidence intervals were used to assess variables that might be associated with positive NAAT results for sputum and bronchoalveolar lavage fluid from patients with suspected PTB.ResultsNAAT showed higher sensitivity for Mtb detection (61.1%) when compared with smear (9.0%) and Mtb culture (47.8%). We found that an elevated erythrocyte sedimentation rate, the presence of cavities, and positive interferon-γ release assay (IGRA) results were indicative of positive Mtb detection by NAAT. Moreover, individuals who had all three of these characteristics showed an 86% diagnostic positivity for PTB from Mtb detection by NAAT.ConclusionsOur study suggests that an elevated erythrocyte sedimentation rate, a positive IGRA result, and the presence of pulmonary cavities are helpful factors for predicting positive Mtb detection by NAAT. Patients with the three positive clinical markers should undergo NAAT for Mtb detection because they are the most likely individuals to be bacteriologically confirmed as having TB.
Project description:BackgroundRadiation pneumonitis (RP) is a frequent complication of concurrent chemoradiotherapy (CCRT) and is associated with severe symptoms that decrease quality of life and might result in pulmonary fibrosis or death. The aim of this study is to identify whether pulmonary function test (PFT) abnormalities may predict RP in non-small cell lung cancer (NSCLC) patients.MethodsA prospective multi-institutional study was conducted with locally advanced and oligometastatic NSCLC patients. All participants were evaluated at baseline, end of CCRT, week 6, 12, 24, and 48 post-CCRT. They completed forced spirometry with a bronchodilator, body plethysmography, impulse oscillometry, carbon monoxide diffusing capacity (DLCO), molar mass of CO2, six-minute walk test and exhaled fraction of nitric oxide (FeNO). Radiation pneumonitis was assessed with RTOG and CTCAE. The protocol was registered in www.clinicaltrials.gov (NCT01580579), registered April 19, 2012.ResultsFifty-two patients were enrolled; 37 completed one-year follow-up. RP ≥ Grade 2 was present in 11/37 (29%) for RTOG and 15/37 (40%) for CTCAE. Factors associated with RP were age over 60 years and hypofractionated dose. PFT abnormalities at baseline that correlated with the development of RP included lower forced expiratory volume in one second after bronchodilator (p = 0.02), DLCO (p = 0.02) and FeNO (p = 0.04). All PFT results decreased after CCRT and did not return to basal values at follow-up.ConclusionsFEV1, DLCO and FeNO prior to CCRT predict the development of RP in NSCLC. This study suggests that all patients under CCRT should be assessed by PFT to identify high-risk patients for close follow-up and early treatment.
Project description:ImportanceRemoval of race correction in pulmonary function tests (PFTs) is a priority, given that race correction inappropriately conflates race, a social construct, with biological differences and falsely assumes worse lung function in African American than White individuals. However, the impact of decorrecting PFTs for African American patients with lung cancer is unknown.ObjectivesTo identify how many hospitals providing lung cancer surgery use race correction, examine the association of race correction with predicted lung function, and test the effect of decorrection on surgeons' treatment recommendations.Design, setting, and participantsIn this quality improvement study, hospitals participating in a statewide quality collaborative were contacted to determine use of race correction in PFTs. For hospitals performing race correction, percent predicted preoperative and postoperative forced expiratory volume in 1 second (FEV1) was calculated for African American patients who underwent lung cancer resection between January 1, 2015, and September 31, 2022, using race-corrected and race-neutral equations. US cardiothoracic surgeons were then randomized to receive 1 clinical vignette that differed by the use of Global Lung Function Initiative equations for (1) African American patients (percent predicted postoperative FEV1, 49%), (2) other race or multiracial patients (percent predicted postoperative FEV1, 45%), and (3) race-neutral patients (percent predicted postoperative FEV1, 42%).Main outcomes and measuresNumber of hospitals using race correction in PFTs, change in preoperative and postoperative FEV1 estimates based on race-neutral or race-corrected equations, and surgeon treatment recommendations for clinical vignettes.ResultsA total of 515 African American patients (308 [59.8%] female; mean [SD] age, 66.2 [9.4] years) were included in the study. Fifteen of the 16 hospitals (93.8%) performing lung cancer resection for African American patients during the study period reported using race correction, which corresponds to 473 African American patients (91.8%) having race-corrected PFTs. Among these patients, the percent predicted preoperative FEV1 and postoperative FEV1 would have decreased by 9.2% (95% CI, -9.0% to -9.5%; P < .001) and 7.6% (95% CI, -7.3% to -7.9%; P < .001), respectively, if race-neutral equations had been used. A total of 225 surgeons (194 male [87.8%]; mean [SD] time in practice, 19.4 [11.3] years) were successfully randomized and completed the vignette items regarding risk perception and treatment outcomes (76% completion rate). Surgeons randomized to the vignette with African American race-corrected PFTs were more likely to recommend lobectomy (79.2%; 95% CI, 69.8%-88.5%) compared with surgeons randomized to the other race or multiracial-corrected (61.7%; 95% CI, 51.1%-72.3%; P = .02) or race-neutral PFTs (52.8%; 95% CI, 41.2%-64.3%; P = .001).Conclusions and relevanceGiven the findings of this quality improvement study, surgeons should be aware of changes in PFT testing because removal of race correction PFTs may change surgeons' treatment decisions and potentially worsen existing disparities in receipt of lung cancer surgery among African American patients.
Project description:BackgroundThe rate of lung-function decline in chronic obstructive pulmonary disease (COPD) varies substantially among individuals. We sought to develop and validate an individualized prediction model for forced expiratory volume at 1 second (FEV1) in current smokers with mild-to-moderate COPD.MethodsUsing data from a large long-term clinical trial (the Lung Health Study), we derived mixed-effects regression models to predict future FEV1 values over 11 years according to clinical traits. We modelled heterogeneity by allowing regression coefficients to vary across individuals. Two independent cohorts with COPD were used for validating the equations.ResultsWe used data from 5594 patients (mean age 48.4 yr, 63% men, mean baseline FEV1 2.75 L) to create the individualized prediction equations. There was significant between-individual variability in the rate of FEV1 decline, with the interval for the annual rate of decline that contained 95% of individuals being -124 to -15 mL/yr for smokers and -83 to 15 mL/yr for sustained quitters. Clinical variables in the final model explained 88% of variation around follow-up FEV1. The C statistic for predicting severity grades was 0.90. Prediction equations performed robustly in the 2 external data sets.InterpretationA substantial part of individual variation in FEV1 decline can be explained by easily measured clinical variables. The model developed in this work can be used for prediction of future lung health in patients with mild-to-moderate COPD.Trial registrationLung Health Study - ClinicalTrials.gov, no. NCT00000568; Pan-Canadian Early Detection of Lung Cancer Study - ClinicalTrials.gov, no. NCT00751660.
Project description:COPD is a major cause of disability, but little is known about how disability develops in this condition.The authors analysed data from the Function, Living, Outcomes and Work (FLOW) Study which enrolled 1202 Kaiser Permanente Northern California members with COPD at baseline and re-evaluated 1051 subjects at 2-year follow-up. The authors tested the specific hypothesis that the development of specific non-respiratory impairments (abnormal body composition and muscle strength) and functional limitations (decreased lower extremity function, poor balance, mobility-related dyspnoea, reduced exercise performance and decreased cognitive function) will determine the risk of disability in COPD, after controlling for respiratory impairment (FEV(1) and oxygen saturation). The Valued Life Activities Scale was used to assess disability in terms of a broad range of daily activities. The primary disability outcome measure was defined as an increase in the proportion of activities that cannot be performed of 3.3% or greater from baseline to 2-year follow-up (the estimated minimal important difference). Multivariable logistic regression was used for analysis.Respiratory impairment measures were related to an increased prospective risk of disability (multivariate OR 1.75; 95% CI 1.26 to 2.44 for 1 litre decrement of FEV(1) and OR 1.57 per 5% decrement in oxygen saturation; 95% CI 1.13 to 2.18). Non-respiratory impairment (body composition and lower extremity muscle strength) and functional limitations (lower extremity function, exercise performance, and mobility-related dyspnoea) were all associated with an increased longitudinal risk of disability after controlling for respiratory impairment (p<0.05 in all cases). Non-respiratory impairment and functional limitations were predictive of prospective disability, above-and-beyond sociodemographic characteristics, smoking status and respiratory impairment (area under the receiver operating characteristic curve increased from 0.65 to 0.75; p<0.001).Development of non-respiratory impairment and functional limitations, which reflect the systemic nature of COPD, appear to be critical determinants of disablement. Prevention and treatment of disability require a comprehensive approach to the COPD patient.