Prognostic impact of corticosteroid maintenance dose and re-escalation in patients with cardiac sarcoidosis

BACKGROUND: Japanese guidelines recommend a corticosteroid maintenance dose of 5-10 mg/day for cardiac sarcoidosis (CS); however, the optimal dose remains unclear. This study aimed to evaluate the impact of maintenance dose and corticosteroid re-escalation on prognosis in patients with CS. METHODS: This multicentre retrospective cohort study used data from a Japanese nationwide CS registry. A total of 352 patients diagnosed according to the Japanese Circulation Society 2016 guideline and treated with oral corticosteroids were included. Patients were grouped by maintenance dose: low (10.0 mg/day). Clinical outcomes were analysed. The main outcome was all-cause mortality. RESULTS: The low-dose, recommended-dose and high-dose groups comprised 11% (n=40), 78% (n=276) and 10% (n=36) of patients, with mean maintenance doses of 2.2 mg/day, 6.7 mg/day and 16.2 mg/day, respectively. During a median follow-up of 5.12 years, 39 patients (11%) died. Kaplan-Meier survival analysis showed statistically better survival in the recommended dose group, with the high-dose group showing statistically significantly worse outcomes (log-rank p=0.012). Corticosteroid re-escalation occurred in 19% of patients (9% before and 11% after achieving maintenance dose). All-cause mortality was 8% in the recommended-dose group versus 25% in the low-dose and 17% in the high-dose groups. In univariable analyses, re-escalation after achieving maintenance was associated with mortality in the high-dose group (HR 4.34, 95% CI 1.24 to 98.3), whereas re-escalation before achieving maintenance was associated with mortality in the low-dose group (HR 19.41, 95% CI 2.71 to 138.5). CONCLUSIONS: A recommended maintenance dose of corticosteroids was associated with better prognosis in patients with CS. Achieving and maintaining this dose appears critically important in clinical management.