MUC5B rs35705950 Promoter Variant Is Associated with Usual Interstitial Pneumonia in Patients with Antisynthetase Syndrome

Abstract

Background: The presence of the rs35705950 variant in the MUC5B gene promoter is a critical genetic risk factor in idiopathic pulmonary fibrosis (IPF). It has been associated with usual interstitial pneumonia (UIP) in several interstitial lung diseases (ILDs). In antisynthetase syndrome (ASSD), most high-resolution computed tomography (HRCT) patterns are inflammatory, but up to 13% have UIP, leading to a worse prognosis. Methods: This single-center study included 60 patients with ASSD-ILD. We investigated whether carrying the MUC5B rs35705950 promoter variant was associated with UIP. To estimate the strength of the association between the genotype of the MUC5B rs35705950 promoter variant and the fibrotic pattern we used the odds ratio (cOR), and to assess the effect of confounding variables (age, evolution time, and sex), we performed a logistic regression to obtained the adjusted odds ratio (aOR). Results: The GT genotype of the MUC5B rs35705950 promoter variant is associated with up to a 4-fold increased risk of UIP (cOR 5.0, 95% CI 1.13–22.10), and the effect was even maintained after adjusting for potentially confounding variables such as sex, age, and time to progression (aOR 5.2, 95% CI 1.04–25.89). Conclusions: our study supports the role of MUC5B rs35705950 in ASSD-ILD with UIP. It reinforces that this polymorphism in our population could have a similar genetic basis to that already described in other ILDs that present predominantly fibrotic patterns.