Aggressive management of ILD as a complication of idiopathic inflammatory myopathies can maintain lung function
Presenter: Hema Balina, MD
A single-center retrospective study suggests that aggressive management of idiopathic inflammatory myositis (IIM)-related interstitial lung disease (ILD) may preserve lung function and reduce the rate of death.1
ILD is a complication in patients with IIM, and the mortality rate of IIM-related ILD is about 80%, said Hema Balina, MD, from the University of Alabama at Birmingham (UAB), who presented the findings from the UAB experience.
A total of 32 patients with IIM-related ILD between 2014 and 201 formed the study cohort. Their charts were examined for demographic data and treatment data, and the results from spirometry and the 6-minute walk test as well as response to treatment were evaluated at each patient visit. Patients were followed for at least 3 years after diagnosis until March 2020 or death.
Mean age of the cohort at time of diagnosis was 51.1, the ratio of men to women was 30 to 70, 61% were African American, mean body mass index was 29.8 kg/m2, mean forced vital capacity (FVC) was 56%, and mean diffusing capacity for carbon monoxide was 45%.
“All of these patients had serologic evidence of myositis-specific antibodies or myositis-associated antibodies and elevated [creatine kinase] levels; however, the ILD diagnosis was made prior to the development of myositis in 48% of patients,” said Dr. Balina. This percentage is far higher than the 20% reported in the literature, she noted.
Prednisone was used as part of a tapered treatment regimen with steroid-sparing agents in 84% of the patients. Azathioprine was chosen as first-line treatment in 55% of patients and mycophenolate mofetil in 36%. In the remaining 9% of patients, either cyclophosphamide or methotrexate was chosen.
The treatment regimen was changed in 67% of patients, and the changes were mainly secondary to lack of response or deterioration of lung function (n = 10) or intolerance to side effects (n = 9). “In only a few patients was treatment changed due to socioeconomic factors,” said Dr. Balina.
Rituximab was used in ILD refractory to first-line immunosuppression in 34% (n = 11) of patients and in 2 others who could not tolerate other agents.
An improvement in pulmonary function was noted with aggressive treatment, she said. The mean change in FVC at the end of follow-up (83 months) was 0.61 ±0.5 L/min. Disease worsening was observed in 37% of patients. Only 3 patients had died at the end of the follow-up period.
In addition to aggressive management, the study shows that frequent monitoring of treatment response can improve outcomes in IIM-related ILD, Dr. Balina concluded.
Reference
- Balina H, Dsouza K, Acosta Lara P, Luckhardt T, Kulkarni T, Gulati S. Natural history of interstitial lung disease (ILD) and response to treatment regimens in patients with idiopathic inflammatory myopathies (IIM): a single center experience. CHEST 2020; 158(4 Suppl):A1046–A1047. doi:https://doi.org/10.1016/j.chest.2020.08.971