Moyamoya disease in a European setting: a Danish population-based study

Area of Science:

• Neurology
• Epidemiology
• Radiology

Background:

• Moyamoya disease (MMD) incidence in Europe is poorly understood.
• The risk of brain hemorrhage in MMD patients is often underestimated.
• Previous data on MMD prevalence in Denmark is limited.

Purpose of the Study:

• To determine the incidence of Moyamoya disease in the Danish population.
• To describe the clinical presentation of MMD in Denmark.
• To assess the demographic characteristics of MMD patients in Denmark.

Main Methods:

• Utilized the Danish National Patient Register (1994-2017) for patient identification.
• Collected clinical and radiological data from patient records across Denmark.
• Validated MMD diagnoses using established criteria and demographic data from the Danish Civil Registration System.

Main Results:

• Identified 52 patients meeting MMD diagnostic criteria.
• Observed an incidence rate of 0.07 per 100,000 person-years from 2008 onwards.
• Common presentations included ischemic stroke (33%), hemorrhage (23%), headache (17%), and transient ischemic attack (14%).

Conclusions:

• Moyamoya disease is rare in Denmark but carries a notable risk of hemorrhage.
• MMD should be considered in the differential diagnosis of ischemic and hemorrhagic strokes in pediatric and middle-aged Caucasian populations.
• Increased awareness and diagnostic evaluation are crucial for MMD in Denmark.