High incidence of NMDAR encephalitis among Austronesians: A population-based study in Sabah, Malaysia

NMDAR encephalitis may be more common among non-Caucasians. A population-based study was conducted to estimate its incidence in Sabah, Malaysia, where the population consists predominantly of Austronesians (84%), and with a Chinese minority. Registries of NMDAR encephalitis at neurology referral centers were reviewed for case ascertainment. The annual incidence was 2.29/million (Austronesians: 2.56/million, Chinese: 1.31/million). Among pediatric population, the incidence was: Austronesians: 3.63/million, Chinese: 2.59/million. Our study demonstrated a higher incidence of NMDAR encephalitis among Austronesians than the predominantly Caucasian populations in Europe (0.5–0.9/million; pediatric: 0.7–1.5/million). Racial and genetic factors may contribute to risks of developing NMDAR encephalitis. [Display omitted] •NMDAR encephalitis was observed to be more common among non-Caucasians.•High annual incidence (2.56/million) among Austronesians in Sabah, Malaysia.•In Sabah Austronesian pediatric population, the annual incidence was 3.63/million.•This was higher than in European populations (