Elderly sarcoidosis in Japan

OBJECTIVE: The manifestations of sarcoidosis differ by ethnicity and region. However, the few studies that have focused on elderly sarcoidosis are only from Western countries. Therefore, we investigated elderly sarcoidosis in Japan. METHODS: We retrospectively reviewed the records of adult patients (≥18 years old) who were diagnosed with sarcoidosis from 1 April 2006 to 31 March 2020. The diagnosis was pathologically confirmed in all patients. We compared the clinical features of elderly (diagnosed at ≥65 years old) and non-elderly (diagnosed at <65 years old) patients. RESULTS: Thirty-five (33%) of 106 patients were elderly. The elderly group had significantly more comorbidities than the non-elderly group (median [range], 1 [0–4] vs. 0 [0–5]). The biopsy site at diagnosis included significantly more extrathoracic sites in the elderly than non-elderly group (57.1% vs. 33.8%). The elderly group had significantly more muscle lesions than the non-elderly group at the time of diagnosis (11.4% vs. 1.4%) and at any time during follow-up (17.1% vs. 1.4%). CONCLUSION: In Japan, elderly patients with sarcoidosis might have more muscle involvement and comorbidities than younger patients. Because comorbidities might affect the prognosis of elderly sarcoidosis, further study is needed to clarify the effect of comorbidities on elderly sarcoidosis.