Thimerosal exposure in infants and neurodevelopmental disorders: An assessment of computerized medical records in the Vaccine Safety Datalink

• Published in: Journal of the neurological sciences Vol. 271; no. 1; pp. 110 - 118
• Main Authors: Young, Heather A., Geier, David A., Geier, Mark R.
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier B.V 15.08.2008; Elsevier Science
• Subjects: ADD; ADHD autistic disorder; Adolescent; ASD; Biological and medical sciences; Child; Child Development Disorders, Pervasive - chemically induced; Child Development Disorders, Pervasive - epidemiology; Child, Preschool; Cohort Studies; Developmental Disabilities - chemically induced; Developmental Disabilities - epidemiology; Ethylmercury; Evaluation Studies as Topic; Female; Forensic medicine; Humans; Infant; Male; Medical Records Systems, Computerized - statistics & numerical data; Medical sciences; Merthiolate; Neurology; Preservatives, Pharmaceutical - adverse effects; Proportional Hazards Models; Public health. Hygiene; Public health. Hygiene-occupational medicine; Retrospective Studies; Thimerosal - adverse effects; Thiomersal; Vaccines - adverse effects; Vaccines - therapeutic use; ADD; ADHD; VAERS; FDA; Ethylmercury; CDC; Thiomersal; VSD; ADHD autistic disorder; μg; TCVs; ASD; ICD-9; Merthiolate; ATSDR; EPA; IRB; NDs; Hg; micrograms; US Agency for Toxic Substances and Disease Registry; Autism Spectrum Disorder; neurodevelopmental disorders; Institutional Review Board; US Centers for Disease Control and Prevention; US Food and Drug Administration; Vaccine Adverse Event Reporting System; International Classification of Disease, 9th revision; Thimerosal-containing vaccines; Attention Deficit Disorder; Vaccine Safety Datalink; Attention Deficit Hyperactivity Disorder; Mercury; US Environmental Protection Agency; Human; Nervous system diseases; Infant; Developmental disorder; Vaccine; Prevention; Autism; Medical record; Attention disorder with hyperactivity; Safety
• ISSN: 0022-510X; 1878-5883
• DOI: 10.1016/j.jns.2008.04.002

The study evaluated possible associations between neurodevelopmental disorders (NDs) and exposure to mercury (Hg) from Thimerosal-containing vaccines (TCVs) by examining the automated Vaccine Safety Datalink (VSD). A total of 278,624 subjects were identified in birth cohorts from 1990–1996 that had received their first oral polio vaccination by 3 months of age in the VSD. The birth cohort prevalence rate of medically diagnosed International Classification of Disease, 9th revision (ICD-9) specific NDs and control outcomes were calculated. Exposures to Hg from TCVs were calculated by birth cohort for specific exposure windows from birth-7 months and birth-13 months of age. Poisson regression analysis was used to model the association between the prevalence of outcomes and Hg doses from TCVs. Consistent significantly increased rate ratios were observed for autism, autism spectrum disorders, tics, attention deficit disorder, and emotional disturbances with Hg exposure from TCVs. By contrast, none of the control outcomes had significantly increased rate ratios with Hg exposure from TCVs. Routine childhood vaccination should be continued to help reduce the morbidity and mortality associated with infectious diseases, but efforts should be undertaken to remove Hg from vaccines. Additional studies should be conducted to further evaluate the relationship between Hg exposure and NDs.