Interstitial Lung Disease and Progressive Pulmonary Fibrosis: a World Trade Center Cohort 20-Year Longitudinal Study.

PURPOSE: World Trade Center (WTC) exposure is associated with obstructive airway diseases and sarcoidosis. There is limited research regarding the incidence and progression of non-sarcoidosis interstitial lung diseases (ILD) after WTC-exposure. ILD encompasses parenchymal diseases which may lead to progressive pulmonary fibrosis (PPF). We used the Fire Department of the City of New York's (FDNY's) WTC Health Program cohort to estimate ILD incidence and progression. METHODS: This longitudinal study included 14,525 responders without ILD prior to 9/11/2001. ILD incidence and prevalence were estimated and standardized to the US 2014 population. Poisson regression modeled risk factors, including WTC-exposure and forced vital capacity (FVC), associated with ILD. Follow-up time ended at the earliest of incident diagnosis, end of study period/case ascertainment, transplant or death. RESULTS: ILD developed in 80/14,525 FDNY WTC responders. Age, smoking, and gastroesophageal reflux disease (GERD) prior to diagnosis were associated with incident ILD, though FVC was not. PPF developed in 40/80 ILD cases. Among the 80 cases, the average follow-up time after ILD diagnosis was 8.5 years with the majority of deaths occurring among those with PPF (PPF: n = 13; ILD without PPF: n = 6). CONCLUSIONS: The prevalence of post-9/11 ILD was more than two-fold greater than the general population. An exposure-response gradient could not be demonstrated. Half the ILD cases developed PPF, higher than previously reported. Age, smoking, and GERD were risk factors for ILD and PPF, while lung function was not. This may indicate that lung function measured after respirable exposures would not identify those at risk for ILD or PPF.

Six-Minute Walk Test: Clinical Role, Technique, Coding, and Reimbursement.

The 6-min walk test (6MWT) is a commonly used test for the objective assessment of functional exercise capacity for the management of patients with moderate-to-severe pulmonary disease. Unlike pulmonary function testing, the 6MWT captures the often coexisting extrapulmonary manifestations of chronic respiratory disease, including cardiovascular disease, frailty, sarcopenia, and cancer. In contrast with cardiopulmonary exercise stress testing, this test does not require complex equipment or technical expertise. In this low complexity, safe test, the patient is asked to walk as far as possible along a 30-m minimally trafficked corridor for a period of 6 min with the primary outcome measure being the 6-min walk distance (6MWD) measured in meters. There has been interest in other derived indexes, such as distance-desaturation product (the product of nadir oxygen saturation and walk distance), which in small studies has been predictive of morbidity and mortality in certain chronic respiratory conditions. Special attention to methodology is required to produce reliable and reproducible results. Factors that can affect walk distance include track layout (continuous vs straight), track length, oxygen amount and portability, learning effect, and verbal encouragement. The absolute 6MWD and change in 6MWD are predictive of morbidity and mortality in patients with COPD, pulmonary arterial hypertension, and idiopathic pulmonary fibrosis and patients awaiting lung transplant, highlighting its use in management decisions and clinical trials. As of January 2018, Current Procedural Terminology code 94620 (simple pulmonary stress test) has been deleted and replaced by two new codes, 94617 and 94618. Code 94617 includes exercise test for bronchospasm including pre- and postspirometry, ECG recordings, and pulse oximetry. Code 94618, pulmonary stress testing (eg, 6MWT), includes the measurement of heart rate, oximetry, and oxygen titration when performed. If 94620 is billed after January 2018 it will not be reimbursed.

Which pulmonary function tests best differentiate between COPD phenotypes?

We are still at the early phase of finding useful phenotypes in COPD that can guide therapy. However, in a simple sense, "sick patients die." Many phenotypic measurements of severity correlate with mortality in COPD: FEV(1), the ratio of inspiratory capacity to total lung capacity (IC/TLC), diffusing capacity of the lung for carbon monoxide (D(LCO)), 6-min walk distance, and maximum oxygen (O(2)) consumption or maximum watts on exercise testing. However, composite parameters, such as the BODE index (body mass index, air flow obstruction, dyspnea, exercise capacity), perform better, likely because they capture different aspects of severity that affect functional impairment and risk of death. Bronchodilator responsiveness is just a relative feature that aids in distinction of asthma and COPD but is not diagnostic in this use. A normal D(LCO) helps to rule out exercise-induced O(2) desaturation, but those with a low D(LCO) and COPD need exercise measurements to confirm desaturation. Currently, pulmonary function tests (PFTs) alone do not define subsets who respond to particular therapies. The presence of air flow obstruction and its severity increase the risk of lung cancer in COPD patients. Inflammatory biomarkers (exhaled nitric oxide and eosinophilia in sputum or bronchoalveolar lavage fluid) help distinguish asthma from COPD. Genetics is a promising area to elucidate pathophysiology and treatment for asthma and COPD, but currently alpha-1 antitrypsin deficiency is the only genetically-determined phenotype that has relevance for COPD management. The best promise for the future seems to be in composite phenotypes or scores, both for distinguishing asthma from COPD, and for guiding therapeutic options. It may be better to throw out the old, limiting diagnostic concepts. If, instead, we start from outcomes of interest, perhaps we can work back to predictors of these outcomes, and organize new diagnostic entities that have predictive relevance for treatment choices, functional outcomes, and mortality.

The 6-min walk test: clinical and research role, technique, coding, and reimbursement.

FEV(1) is recommended for rating the severity of obstructive and restrictive pulmonary diseases, but it only moderately correlates with quality of life, mortality, and functional status. The 6-min walk test (6MWT) has been increasingly used in clinical practice and research studies as an objective measurement of functional status in patients with moderate-to-severe impairment. This low complexity test measures the distance a patient can quickly walk back and forth in a 30-m (100-foot) corridor in a period of 6 min, referred to as the 6-min walk distance (6MWD). The 6MWD, and in some circumstances oxygen desaturation during the 6MWT, are useful to assess response to medical interventions, to assess prognosis in various conditions, and as a single measurement of functional status. Strictly scripted test instructions and encouragement at baseline and at each minute of exercise is vital to obtain reproducible results. The 6MWT is reported using Current Procedural Terminology code 94620 (simple pulmonary stress test). This code is also appropriate for other simple exercise tests, including oxygen titration (if additional parameters are measured), exercise-induced bronchospasm evaluation using pre- and postexercise spirometry, and exercise prescription for pulmonary rehabilitation. Use of code 94620 to bill for services must be supported by significant documentation.

Early respiratory abnormalities in emergency services police officers at the World Trade Center site.

The effects of exposure to the environment around the World Trade Center after the attack of September 11, 2001, are not fully described. We evaluated 240 police first-responders; respiratory symptoms occurred in 77.5% but resolved or improved in around three fourths of subjects by the time of their evaluation (mean 69 days after the attack). Cough was the most common symptom (62.5%). Spirometric abnormalities were mild and occurred in 28.8%. Independent risk factors for abnormal spirometry were previous pulmonary disease or symptoms (adjusted odds ratio, 2.76) and intensity of exposure (AOR, 2.32). Previous pulmonary conditions were associated with obstructive defects (P<0.002). Exposure intensity was associated with a lower forced vital capacity (P<0.03) and a higher prevalence of abnormal spirometry (P<0.03). Officers with dyspnea, chest discomfort, or wheeze were more likely to have abnormal spirometry (P=0.04). A significant minority of officers had symptoms a few months after the exposure. Long-term effects of this respiratory tract exposure will need additional evaluation.

Bronchoscopy in the human immunodeficiency virus-infected patient.

The spectrum of pulmonary manifestations in patients infected with human immunodeficiency virus (HIV) is broad, including many infectious and noninfectious complications. In the evaluation of an HIV-infected patient with diffuse pulmonary disease a definitive diagnosis is preferred over empiric therapy in most patients. Patients with focal consolidation usually receive empiric treatment for community-acquired pneumonia, with nonresponders undergoing additional diagnostic testing. Bronchoscopy remains a cornerstone in the diagnostic evaluation. A multilobar bronchoalveolar lavage (BAL) is usually sufficient for the diagnosis of Pneumocystis carinii pneumonia (PCP) and avoids the additional complications of hemorrhage and pneumothorax associated with transbronchial biopsy (TBBX). However, TBBX improves the sensitivity for diagnosis of tuberculosis and fungal pneumonias and is necessary to confirm invasive aspergillosis. Definitive criteria for diagnosis of cytomegalovirus pneumonitis have yet to be established, although bronchoscopic specimens usually are used. Tissue confirmation with TBBX is required for the diagnosis of noninfectious disorders such as non-Hodgkin's lymphoma and lymphocytic and nonspecific pneumonitis. Bronchoscopic visualization of typical lesions often is sufficient for the presumptive diagnosis of Kaposi's sarcoma (KS) although the diagnostic yield is enhanced by the detection of human herpes virus 8 in BAL samples.

Dyspnea-fasciculation syndrome: early respiratory failure in ALS with minimal motor signs.

BACKGROUND: Respiratory failure (RF) in ALS typically occurs as a late manifestation. While there are uncommon patient reports of early RF, most had moderate limb and bulbar weakness. DESIGN/METHODS: We reviewed clinical and laboratory data from 3 patients with ALS, early RF, and minor motor signs. RESULTS: Patients were male, ages 62, 75 and 80 years. The patients presented with 6 months to 2 years of exertional and nocturnal dyspnea, daytime hypersomnolence, limb fatigability, and weight loss. Exam showed tachypnea, slight distal limb weakness, and hyperreflexia. All three patients had prominent fasciculations, insomnia, supportive EMG findings, FVC (32-74% predicted), PO2 (50-80 mmHg), PCO2(52-76 mmHg) and required BiPAP (Bi-level positive airway pressure). One patient had a reduced FEV1/FVC of 0.55 and a 15% increase in FEV1 post-bronchodilator suggesting concurrent chronic obstructive pulmonary disease (COPD). However, his P(A-a)O2 was only 7 mmHg suggesting COPD was not the major factor causing respiratory failure; his extreme hypercapnea could not be explained by ALS or COPD alone. CONCLUSIONS: ALS may present with unexplained RF, or sleep disturbance resembling sleep apnea, without significant bulbar or limb weakness. In our experience, such patients are elderly with dyspnea, fasciculations, and other minor motor signs: the Dyspnea-Fasciculation Syndrome. Concurrent COPD may augment the effect of ALS, resulting in earlier RF. FVC may be relatively preserved, despite hypercapnia.