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Background/Objectives Moyamoya disease (MMD) is an arteriopathy that presents with ischaemic and haemorrhagic stroke. MMD is uncommon in Europeans (1 in 1,100,000) but has a high prevalence (2–10 in 100,000) in people of East Asian ancestry (Chinese, Japanese, Korean) with an associated genetic risk variant (RFN213). We aimed to characterise MMD in a New Zealand cohort to determine if there was any increase in people of Māori or Pacific ancestry.Methods Patients diagnosed with MMD were identified from 15 years of electronic hospital records from northern New Zealand, which has a population of 1.8 million of whom 17% are of Māori and 22% of Pacific ancestry. MMD was defined by radiological criteria with other causes excluded (autoimmune disease, past meningitis, brain tumor, trisomy 21, neurofibromatosis or previous radiotherapy).Results 64 patients were identified with arteriopathy of whom 26 had exclusion diagnoses leaving 38 with probable MMD (23 women, mean age [SD] 41.8 [16.8] years). 20 (53%) had Māori or Pacific ancestry (15 women, mean age [SD] 39.7 [15.9] years), and 18 were of other ethnic groups (8 women, mean age [SD] 44.1 [17.5] years, 12 East Asian and 6 NZ European). The prevalence of MMD in Māori was 1.8 per 100,000 people and in Pacific people 5 per 100,000.Conclusions MMD is more common in people of Māori and Pacific ancestry, which may be related to historic migration of these populations from South East Asia. We plan to further investigate this link by performing whole genome sequencing in this cohort.