An Inventory of Clinical Sarcoidosis Status in the United States

Abstract

Background: The landscape of sarcoidosis in the United States is unclear, which makes it difficult to optimize the allocation of health care resources, clinical care programs, and research activities for sites that specialize in sarcoidosis.

Research question: Can the features of sarcoidosis be defined in patients requiring specialty care in the United States to inform the design of clinical management and research programs?

Study design and methods: Adult patients with sarcoidosis were enrolled in this multicenter, longitudinal cohort study. Demographic and clinical characteristics, including lung function and imaging features, were recorded at baseline. Patients were followed up for a median of 21 months (interquartile range, 9-27 months).

Results: The cohort comprised 2,034 patients from 39 states. Even when excluding lymph node involvement, 51.8% of patients had multi-organ disease, and sarcoidosis was chronic (≥ 3 years) for 66.5% of patients. Pulmonary fibrosis was present in 35.9% of those with lung involvement and was associated with worse lung function, an effect most pronounced when bronchiectasis was present. Slightly more than one-half (53.4%) of the cohort required treatment at the time of study entry; of those, 24.8% were on a steroidal regimen alone, 39.7% were on a nonsteroidal regimen alone, and 35.5% were on a combination regimen. During follow-up, there were 120 new organ events, resulting in a new organ rate of 5.5 per 100 patient-years (95% CI, 4.6-6.6). Cardiac sarcoidosis was present in 16.2% of patients at baseline, and emergent cardiac involvement was the most common new organ phenotype during follow-up.

Interpretation: Sarcoidosis is frequently chronic and dynamic. These data support the need for programs aimed at preventing and treating pulmonary fibrosis and cardiac sarcoidosis, as well as the development of long-term, multidisciplinary management strategies.

Keywords: bronchiectasis; chronic inflammation; pulmonary fibrosis; pulmonary function; race; sarcoidosis; smoking; socioeconomic status; treatment.