Stroke and disease progression during long-term follow-up of patients with moyamoya disease older than 50 years

Objectives The long-term prognosis of elderly patients with moyamoya disease (MMD) is not fully understood and needs to be elucidated. Materials and Methods MMD patients who first visited our institute between 1999 and 2019, were ≥50 years of age, and were followed for ≥ 1 year were retrospectively included. Follow-up data such as stroke and disease progression on magnetic resonance angiography (MRA) were collected from medical records. The surgical outcomes of ischemic patients treated with indirect revascularization were assessed. Results Of the 60 patients included (mean (standard deviation) = 57.0 (5.5) years, 38 females), 9 patients initially received indirect revascularization, 3 patients received direct revascularization, and 49 patients were treated conservatively. During the 57.4 (53.7) month follow-up, the symptomatic stroke rate (person-year %) was 2.79%, and MRA progression was 3.14%. Symptomatic patients had a greater rate of symptomatic stroke than asymptomatic patients did (1.46–5.74% vs. 0.94%, P=0.15), while MRA progression was more common in asymptomatic patients (0–3.83% vs. 5.64%, P=0.22). Among the 14 hemispheres of 11 patients who underwent indirect revascularization, 13/14 (92.9%) demonstrated good neovascularization, and no ischemic stroke occurred after surgery. Conclusions In elderly patients with MMD, MRA progression was not uncommon, especially in asymptomatic patients. Symptomatic patients exhibited a high symptomatic stroke rate, and indirect revascularization seems to be effective at reducing future ischemic stroke in ischemic patients with misery perfusion. Because follow-up events were not uncommon, lifelong follow-up seems necessary for elderly MMD patients, as well as for younger patients.