title: Neurocognitive changes among elderly exposed to PCBs/PCDFs in Taiwan.
abstract: BACKGROUND
  In 1979 approximately 2,000 people were exposed to polychlorinated biphenyls (PCBs) and polychlorinated dibenzofurans (PCDFs) due to ingestion of contaminated cooking oil in Taiwan. Although a previous study has shown delayed developmental milestones and poorer neurocognitive functioning in children born to exposed mothers, it is unclear whether neurocognitive functioning was impaired in people who were directly exposed to the PCBs and PDCFs.
  
  
  OBJECTIVE
  The objective of this study was to compare neurocognitive functioning in people exposed to PCBs and PCDFs with that of unexposed sex- and age-matched neighbors.
  
  
  METHODS
  We conducted a retrospective cohort study among exposed and unexposed subjects > or =60 years of age using prospective outcome measurements. We evaluated neurocognitive tests including cognition, memory modalities, learning, motor and sensory function, mood, and daily activity.
  
  
  RESULTS
  In total, 162 (59%) exposed and 151 (55%) reference subjects completed this study. In exposed men, all test results were similar to the reference group; however, exposed women had reduced functioning in attention and digit span (ADS), visual memory span (VMS), and verbal memory recalls (VMR), especially learning ability. We also found a borderline reduction in the Mini-Mental State Examination. The digit symbol, motor, sensory, depression (determined by the Geriatric Depression Scale-Short Form), and activity of daily life were not different between the exposed and reference groups. A significant dose-response relationship was found for VMR, ADS, and VMS.
  
  
  CONCLUSIONS
  Our study showed dose-dependent neurocognitive deficits in certain aspects of attention, visual memory, and learning ability in women previously exposed to PCBs and PCDFs, but not in exposed men.
authors.affiliation: Department of Neurology, Chi-Mei Medical Center, Tainan, Taiwan.
authors.forename: Kao-Chang
authors.initials: KC
authors.lastname: Lin
authors.forename: Nai-Wen
authors.initials: NW
authors.lastname: Guo
authors.forename: Pei-Chien
authors.initials: PC
authors.lastname: Tsai
authors.forename: Chiu-Yueh
authors.initials: CY
authors.lastname: Yang
authors.forename: YueLiang Leon
authors.initials: YL
authors.lastname: Guo
mesh_terms: D000368:Aged; D001572:Benzofurans / Q000633:toxicity*; D003072:Cognition Disorders / Q000139:chemically induced*; D015331:Cohort Studies; D000072338:Dibenzofurans, Polychlorinated; D004781:Environmental Exposure; D006801:Humans; D008875:Middle Aged; D009422:Nervous System Diseases / Q000139:chemically induced*; D009483:Neuropsychological Tests; D011078:Polychlorinated Biphenyls / Q000633:toxicity*; D013624:Taiwan
chemical_list: D001572:Benzofurans; D000072338:Dibenzofurans, Polychlorinated; D011078:Polychlorinated Biphenyls