Epidemiological and clinical features of Moyamoya disease in Nanjing, China.

The epidemiology of Moyamoya disease in mainland China has not been documented. Therefore, the present study was designed to examine the epidemiological and clinical features of Moyamoya disease in Nanjing, a provincial capital in China.Patient records from multiple hospitals in Nanjing from January 2000 to December 2007 were collected. The clinical features of Moyamoya disease were retrospectively analyzed.A total of 202 patients were identified. There were 94 males and 108 females, with ages ranging from 2 to 78 years. There was a dual age peak, one in the group of patients 5-9 years of age and another in the group of patients 35-39 years of age. The initial symptoms included cerebral ischemia (81 patients, 40%), cerebral hemorrhage (113 patients, 55.9%) and asymptomatic disease (8 patients, 3.9%). An increasing incidence rate of Moyamoya disease was observed during the period of 2000-2007, with an average detection rate of 0.43cases/100,000 persons/year (prevalence 3.92/100,000 persons). The incidence of ischemia associated with the disease was 0.16cases/100,000 people-years and the incidence of hemorrhage was 0.22cases/100,000 people-years.This first study on the epidemiological and clinical features of Moyamoya disease in mainland China indicated an increasing incidence of Moyamoya disease with bimodal incidence distribution appearing more frequently in adults.