AB0735 Interstitial lung disease associated with systemic connective tissue diseases: dynamics of lung function after three years of follow-up

Abstract

BackgroundInterstitial lung disease (ILD) is one of the most common and severe manifestations of connective tissue diseases, such as systemic scleroderma (SSc), dermato- and polymyositis (DM/PM), mixed connective tissue disease (MCTD), etc.ObjectivesTo compare the course and outcomes of ILD in SSD, MCTD and DM/PM, immunoinflammatory myopathies (IIM) after three years of follow-up.MethodsThe SSc group consisted of 82 patients, the IIM group – 61 patients, and the MCTD group – 20 patients. In all the studied groups, women predominated. The oldest patients were found in the IIM group, and the average age was 51±12.88 years. The duration of the disease varied from 0.5 to 18.5 years. A longer course of the disease was observed among patients with MCTD, the median was 10.6 (6.9; 18.5) years. When assessing the initial parameters of lung function tests, significantly lower values of FVC and DCL were recorded in the IIM group (on average, 82±21.5 and 51.1±16.2, respectively), and higher values in the MCTD group (95.4± 20 and 67.5±15). All patients took GCs, the highest doses were taken by patients with IIM. The great majority of patients received immunosuppressants, of which 100% of patients were in the MCTD group.ResultsDespite the fact that the indices of FVC and DСL in the SSc group were initially lower (on average 91.8±19.1 and 59.2±19.5, respectively) than in the MCTD group. The dynamics of Δ FVC over three years against the background of ongoing therapy was discordant: Δ FVC in the SSc group significantly increased [0.6 (-8; 4.9)], in the MCTD group, it decreased [-5.7 (-10.3; 10.9)]. The mean value of DCL over the follow-up period remained practically the same; the dynamics between the groups was also discordant: it slightly increased in patients with SSc [1.1 (-3.8; 4.6)] and decreased in patients with MCTD [-1.6 (-11.2; 12.6)]. FEV1 decreased in both SSD and MCTD groups, but the alterations were not significant.In the group of patients with IIM during the follow-up period, there was a significant increase in the mean values of Δ DCL, FVC and FEV1 [9.8 (4-16), 13.9 (3.2-28.5), 10.2 (2-26.8)].ConclusionTherefore, due to the study, positive dynamics in lung function in patients with ILD was noticed in the IIM group, stabilization of the pathological process and the absence of progression in the SSc group were achieved, and, despite the initially higher values of FVC and DCL, negative dynamics was detected in the group of patients with MCTD. It is likely that the positive dynamics of lung function in patients with IIM is due not only to an improvement in the condition of the lungs, but also to an increase in muscle strength. A peculiarity of the group of patients with IIM is the high frequency of intake of rituximab in this group (40 patients).Disclosure of InterestsNone declared