Association of Bypass Surgery and Mortality in Moyamoya Disease

Abstract

Background Patients with moyamoya disease (MMD) have a high risk of stroke or death. We investigated whether extracranial to intracranial bypass surgery can reduce mortality by preventing strokes in patients with MMD. Methods and Results This nationwide retrospective cohort study encompassed patients with MMD registered under the Rare Intractable Diseases program via the Relieved Co‐Payment Policy between 2006 and 2019, using the Korean National Health Insurance Service database. Following a 4‐year washout period, landmark analyses were employed to assess mortality and stroke occurrence between the bypass surgery group and the nonsurgical control group at specific time points postindex date (1 month and 3, 6, 12, and 36 months). The study included 18 480 patients with MMD (mean age, 40.7 years; male to female ratio, 1:1.86) with a median follow‐up of 5.6 years (interquartile range, 2.5–9.3; mean, 6.1 years [SD, 4.0 years]). During 111 775 person‐years of follow‐up, 265 patients in the bypass surgery group and 1144 patients in the nonsurgical control group died (incidence mortality rate of 618.1 events versus 1660.3 events, respectively, per 10 5 person‐years). The overall adjusted hazard ratio (HR) revealed significantly lower all‐cause mortality in the bypass surgery group from the 36‐month landmark time point, for any stroke mortality from 3‐ and 6‐month landmark time points, and for hemorrhagic stroke mortality from the 6‐month landmark time point. Furthermore, the overall adjusted HRs for hemorrhagic stroke occurrence were beneficially maintained from all 5 landmark time points in the bypass surgery group. Conclusions Bypass surgery in patients with MMD was associated with a lower risk of all‐cause and hemorrhagic stroke mortality and hemorrhagic stroke occurrence compared with nonsurgical control.

Risk of Stroke after Vaccination against COVID19 in Patients with Moyamoya Disease: Nationwide Cohort Observational Study

“…Despite this, the lack of speci c data on MMD-related stroke risks underscores the need for further research to clarify this potential risk factor. Moreover, our research indicates that RS signi cantly reduces the risk of stroke-related events (OR 0.38 [95% CI 0.21-0.70]) and mortality (OR 0.41 [95% CI 0.24-0.89]), as numerous studies have demonstrated that RS is bene cial in preventing strokes in patients with MMD [37][38][39] . These ndings suggest that maintaining a normal BMI and considering RS as a preventive measure against further stroke, irrespective of COVID-19 considerations.…”