Vasileios Kouranos1, Simon Ward2, Maria A Kokosi1, Diego Castillo3, Felix Chua1, Eoin P Judge1, Suzie Thomas2, Frans Van Tonder4, Arnand Devaraj5, Andrew G Nicholson6, Toby M Maher7, Elisabetta A Renzoni1, Athol U Wells8. 1. Interstitial Lung Disease Unit, Royal Brompton Hospital, London, England. 2. Lung Function Department, Royal Brompton Hospital, London, England. 3. Interstitial Lung Disease Unit, Royal Brompton Hospital, London, England; Interstitial Lung Disease Unit, Hospital de Sant Pau, Barcelona, Spain. 4. Department of Radiology, Royal Brompton Hospital, London, England; Department of Radiology, St Vincent's Hospital Melbourne, Melbourne, VIC, Australia. 5. Department of Radiology, Royal Brompton Hospital, London, England. 6. Department of Histopathology, Royal Brompton and Harefield NHS Foundation Trust and National Heart and Lung Institute, Imperial College, London, England. 7. Interstitial Lung Disease Unit, Royal Brompton Hospital, London, England; NIHR Respiratory Clinical Research Facility, Royal Brompton Hospital, London, the Fibrosis Research Group, National Heart and Lung Institute, Imperial College, London, England. 8. Interstitial Lung Disease Unit, Royal Brompton Hospital, London, England. Electronic address: rbhild@rbht.nhs.uk.
Abstract
BACKGROUND: In cohort studies of pulmonary sarcoidosis, abnormal ventilatory patterns have generally been subdivided into restrictive and obstructive defects. Mixed ventilatory defects have largely been overlooked in pulmonary sarcoidosis, as total lung capacity has seldom been taken into account in historical series. RESEARCH QUESTION: This study evaluated the prevalence of mixed disease in pulmonary sarcoidosis and its clinical associations. STUDY DESIGN AND METHODS: In patients with pulmonary sarcoidosis (N = 1,110), mixed defects were defined according to American Thoracic Society/European Respiratory Society criteria. Clinical data, pulmonary function variables, and vital status were abstracted from clinical records. Chest radiographs were evaluated independently by two experienced radiologists. RESULTS: The prevalence of a mixed ventilatory defect was 10.4% in the whole cohort, rising to 25.9% in patients with airflow obstruction. Compared with isolated airflow obstruction, mixed defects were associated with lower diffusing lung capacity for carbon monoxide levels (50.7 ± 16.3 vs 70.8 ± 18.1; P < .0001), a higher prevalence of chest radiographic stage IV disease (63.5% vs 38.3%; P < .0001), and higher mortality (hazard ratio, 2.36; 95% CI, 1.34-4.15; P = .003). These findings were reproduced in all patient subgroup analyses, including patients with a histologic diagnosis, a clinical diagnosis, incident disease, and prevalent disease. INTERPRETATION: Mixed disease is present in approximately 25% of patients with pulmonary sarcoidosis and airflow obstruction and is associated with lower diffusing lung capacity for carbon monoxide levels, a higher prevalence of stage IV disease, and higher mortality than seen in a pure obstructive defect. These observations identify a distinct phenotype associated with a mixed ventilatory defect, justifying future studies of its clinical and pathogenetic significance.
BACKGROUND: In cohort studies of pulmonary sarcoidosis, abnormal ventilatory patterns have generally been subdivided into restrictive and obstructive defects. Mixed ventilatory defects have largely been overlooked in pulmonary sarcoidosis, as total lung capacity has seldom been taken into account in historical series. RESEARCH QUESTION: This study evaluated the prevalence of mixed disease in pulmonary sarcoidosis and its clinical associations. STUDY DESIGN AND METHODS: In patients with pulmonary sarcoidosis (N = 1,110), mixed defects were defined according to American Thoracic Society/European Respiratory Society criteria. Clinical data, pulmonary function variables, and vital status were abstracted from clinical records. Chest radiographs were evaluated independently by two experienced radiologists. RESULTS: The prevalence of a mixed ventilatory defect was 10.4% in the whole cohort, rising to 25.9% in patients with airflow obstruction. Compared with isolated airflow obstruction, mixed defects were associated with lower diffusing lung capacity for carbon monoxide levels (50.7 ± 16.3 vs 70.8 ± 18.1; P < .0001), a higher prevalence of chest radiographic stage IV disease (63.5% vs 38.3%; P < .0001), and higher mortality (hazard ratio, 2.36; 95% CI, 1.34-4.15; P = .003). These findings were reproduced in all patient subgroup analyses, including patients with a histologic diagnosis, a clinical diagnosis, incident disease, and prevalent disease. INTERPRETATION: Mixed disease is present in approximately 25% of patients with pulmonary sarcoidosis and airflow obstruction and is associated with lower diffusing lung capacity for carbon monoxide levels, a higher prevalence of stage IV disease, and higher mortality than seen in a pure obstructive defect. These observations identify a distinct phenotype associated with a mixed ventilatory defect, justifying future studies of its clinical and pathogenetic significance.
Authors: Robert P Baughman; Marc A Judson; Daniel A Culver; Surinder S Birring; Joseph Parambil; Joyce Zeigler; Elyse E Lower Journal: Sarcoidosis Vasc Diffuse Lung Dis Date: 2021-09-30 Impact factor: 0.670
Authors: Björn Christian Frye; Laura Potasso; Erik Farin-Glattacker; Surrinder Birring; Joachim Müller-Quernheim; Jonas Christian Schupp Journal: BMC Pulm Med Date: 2021-12-03 Impact factor: 3.317