Background and purpose:RNF213 is a susceptibility gene for moyamoya disease (MMD) and over 90% of Japanese patients with MMD have the RNF213 p.R4810K variant. Recent studies have reported that 20 - 25% of East Asian patients with intracranial arterial stenosis also have the p.R4810K variant, while only about 2% of healthy Japanese population have the variant. In this study, we examined the prevalence of this variant in patients with juvenile-onset ischemic stroke.
Methods: This single-center cross-sectional study was completed at the National Cerebral and Cardiovascular Center, Osaka, Japan. We analyzed 70 Japanese patients who suffered ischemic stroke or TIA with intracranial arterial stenosis before their 60th birthday. Patients with cardioembolic stroke or definite/probable MMD were excluded.
Results: The RNF213 p.R4810K variant was found in 24.2% of juvenile-onset stroke patients with intracranial arterial stenosis. This variant was found more often in women than in men (38% vs. 16%, OR 3.3, 95% CI 1.1-10.2, p=0.045). The variant was identified in 35% of the patients with stenosis in the M1 segment of the middle cerebral artery or the A1 segment of the anterior cerebral artery (OR 25.0, 95% CI 1.4-437.8, p<0.01), but in only one patient with intracranial posterior circulation stenosis (Table 1). When restricted to patients with multiple M1 or A1 stenoses, the variant prevalence increased to 56%. Conventional risk factors for stroke, such as smoking, hypertension, diabetes mellitus, dyslipidemia, and family history did not differ between patients with and without the variant.
Conclusion: The RNF213 p.R4810K variant is common for juvenile-onset ischemic stroke with M1 or A1 stenosis.