[1] Fujian Med Univ, Dept Neurol, Union Hosp, Fuzhou 350001, Fujian, Peoples R China
[2] Fujian Med Univ, Sch Publ Hlth, Dept Epidemiol & Hlth Stat, Fuzhou 350122, Fujian, Peoples R China
[3] Fujian Med Univ, Inst Populat Med, Sch Publ Hlth, Fuzhou 350122, Fujian, Peoples R China
[4] Karolinska Inst, Dept Med Epidemiol & Biostat, S-17177 Stockholm, Sweden
[5] Fujian Med Univ, Fujian Prov Key Lab Environm Factors & Canc, Fuzhou 350000, Fujian, Peoples R China