Age is an independent predictor in pathological diagnosis of sarcoidosis: a retrospective analysis of diagnosis by endobronchial ultrasound-guided transbronchial needle aspiration

Background: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is the current major modality for the diagnosis of sarcoidosis with hilar and mediastinal lymphadenopathy because of its higher diagnostic yield and safety; however, predictors for the pathological diagnosis of sarcoidosis by EBUS-TBNA remain uncertain. The objective of this study was to determine a novel predictor for the pathological diagnosis of sarcoidosis by EBUS-TBNA. Methods: Patients with pathological and/or clinical diagnosis of sarcoidosis were identified from patients who underwent EBUS-TBNA between February 2010 and December 2017, retrospectively. We extracted data on age, sex, stage of disease, number of punctured lymph nodes, number of punctures per procedure and target lymph node, and size of punctured lymph node. Next, we divided patients into groups of pathological positive and negative by EBUS-TBNA, and multivariate logistic regression analysis was performed following univariate analyses to evaluate the efficacy of these parameters as a predictive factor of the pathological diagnosis of sarcoidosis by EBUS-TBNA. Results: We selected 89 patients involving 115 mediastinal and hilar lymph nodes. The diagnostic yield of sarcoidosis by EBUS-TBNA was 74/89 (83.1%). There were no significant differences in the size of lymph node and number of punctures between the groups, there was a significant difference in age by univariate analyses. In addition, multivariate logistic regression revealed that age was significantly associated with pathological diagnosis of sarcoidosis by EBUS-TBNA [5 years = 1 unit, odds ratio (OR), 0.79; 95% CI, 0.64–0.97; P=0.03]. Conclusions: The diagnostic yield of sarcoidosis by EBUS-TBNA was higher in younger than older patients. Therefore, age may be a novel independent predictor for the pathological diagnosis of sarcoidosis by EBUS-TBNA.