Abstract
Chronic hypersensitivity pneumonitis (CHP) is a fibrotic parenchymal lung disease that occurs when inhalation of environmental antigens leads to immune dysregulation. Autoimmune features have recently been identified as potentially important among patients with CHP. However, the relationship between hypothyroidism (HT) and CHP is unknown. In this study, we investigate the prevalence and impact of HT among patients with CHP. We conducted a retrospective, case-control analysis. We identified 121 patients at the University of Chicago Interstitial Lung Disease Center with a multidisciplinary diagnosis of CHP. These patients were matched 3:1 according to age, sex, and race to 363 control subjects with asthma from 2006 to 2015. We analyzed demographics, clinical characteristics, and survival between both groups and assessed the relationship of HT with CHP. Survival analysis was performed using Cox proportional hazards modeling. Patients with CHP had higher prevalence of HT (25.6%, n = 31) compared to controls (10.7%, n = 39; OR, 2.86; 95% CI, 1.62-4.99; P < 0.0001). Compared to CHP alone, patients with CHP/HT were more likely to be female (80.6 vs 51.1%, P = 0.004), have increased incidence of autoimmune disease (19.4 vs 3.3%, P = 0.009), antinuclear antibody seropositivity (80.6 vs 57.0%, P = 0.019), and higher TSH levels (4.0 vs 1.9 mIU/L, P < 0.0001). HT was a significant independent predictor of mortality among CHP patients with seropositive ANA (HR, 3.39; 95% CI, 1.31-8.80; P = 0.012). HT is common in patients with CHP and may carry prognostic significance in patients with features of autoimmunity. Further research exploring common pathogenic pathways between autoimmune HT and CHP may illuminate the association of HT with survival.
Highlights
Hypersensitivity pneumonitis (HP) is a diffuse interstitial lung disease (ILD) resulting from a dysregulated immune response to inhaled environmental antigens
We recently showed that features of autoimmunity are common among patients with chronic HP (CHP) [9] and that HT, an autoimmune process characterized by autoantibody-mediated thyroid inflammation and destruction, is prevalent among patients with idiopathic pulmonary fibrosis (IPF) [10]
Radiographic, and pathologic features of HP but had antecedent history of chemotherapy (n = 3) were excluded from the analysis leaving 121 cases for the primary analysis. Of these 121 cases, 75 (62%) had undergone surgical lung biopsy (SLB), which demonstrated histopathologic features of HP, whereas the remainder demonstrated positive serum precipitins to specific antigens, lymphocytosis on bronchoalveolar lavage or compatible high-resolution CT (HRCT) abnormalities that were consistent with their exposure history and clinical features of HP
Summary
Hypersensitivity pneumonitis (HP) is a diffuse interstitial lung disease (ILD) resulting from a dysregulated immune response to inhaled environmental antigens. When HP results in pulmonary fibrosis, known as chronic HP (CHP), survival is worse [4]. Several underlying mechanisms for autoimmune diseases, such as shared genetic pathways, tissue microchimerism, and exposure to environmental antigens, have been implicated in the pathogenesis of CHP [5,6,7,8]. We recently showed that features of autoimmunity are common among patients with CHP [9] and that HT, an autoimmune process characterized by autoantibody-mediated thyroid inflammation and destruction, is prevalent among patients with idiopathic pulmonary fibrosis (IPF) [10]. Chronic hypersensitivity pneumonitis (CHP) is a fibrotic parenchymal lung disease that occurs when inhalation of environmental antigens leads to immune dysregulation. We investigate the prevalence and impact of HT among patients with CHP
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
