Pulmonary function in patients with sporadic lymphangioleiomyomatosis

Abstract

Lymphangioleiomyomatosis (LAM) is a rare systemic disease characterized by proliferation of atypical smooth muscle-like cells and cystic destruction of the lung parenchyma. <b>Aim:</b> To evaluate parameters of pulmonary function tests (PFTs) and their prognostic value in patients with sporadic LAM. <b>Materials and methods:</b> This retrospective study included&nbsp;baseline data from 101 female patients with sporadic LAM who lived in different regions of Russia. All of them underwent functional testing and treatment in Moscow clinics (Pulmonology Research Institute, Sechenov University, City Clinical Hospital named after D.D.Pletnev) in 2009-2020. The disease was diagnosed based on the LAM diagnostic criteria formulated by a group of experts at the initiative of the ERS. <b>Results:</b> The obstructive ventilatory defect was detected in 75 (74 %) patients, restrictive ventilatory defect - in 4 (4 %) patients. There were no pulmonary ventilation disorders in 22 (22 %) patients. The mean FEV₁ value was 62±29 %pred., FEV₁/VC - 56±21 %, RV - 172±73 %pred., RV/TLC- 141±42 %pred., ITGV - 139±43 %pred. A decrease in DL_CO was found in 89 (92 %) out of 97 examined patients. The mean DL_CO value was 48±23 %pred., K_CO&nbsp;- 54±22 %pred. During the observation period, lung transplantation (LT) was performed in 7 women (4&nbsp;- bilateral LT,&nbsp;2 - unilateral LT, and 1 - bilateral LT twice). Of the 94 patients who did not undergo LT, 15 women died. The median transplant-free survival was 8.6 years. The Cox regression model showed that baseline DL_CO and FEV₁ were the main prognostic physiologic factors. <b>Conclusion:</b> The impairment of DL_CO&nbsp;and the obstructive ventilatory defect predominates in sporadic LAM. DL_CO and FEV₁&nbsp;are the most important predictors&nbsp;of survival.