Domain-specific effects of prenatal fluoride exposure on child IQ at 4, 5, and 6-12 years in the ELEMENT cohort
Por:
Goodman, Carly V., Bashash, Morteza, Green, Rivka, Song, Peter, Peterson, Karen E., Schnaas, Lourdes, Mercado-Garcia, Adriana, Martinez-Medina, Sandra, Hernandez-Avila, Mauricio, Martinez-Mier, Angeles M., Tellez-Rojo, Martha, Hu, Howard, Till, Christine
Publicada:
1 ago 2022
Resumen:
Objective: Prenatal exposure to fluoride has been associated with
adverse neurodevelopmental outcomes. However, the neuropsychological
profile of fluoride's developmental neurotoxicity at low levels and the
stability of this relationship across childhood has not been
characterized. We investigated the longitudinal and domain specific
effect of prenatal fluoride exposure on IQ among children ages 4, 5, and
6-12 years in the Early Life Exposures in Mexico to Environmental
Toxicants (ELEMENT) cohort.
Methods: We measured the average of maternal urinary fluoride at each
trimester of pregnancy adjusted for creatinine (MUFCRE). Children were
administered the McCarthy Scales of Children's Abilities at ages 4 (N =
386) and 5 (N = 308), and the Wechsler Abbreviated Scale of Intelligence
at age 6-12 (N = 278). We used generalized estimating equation (GEE)
models to estimate the population averaged effect of MUFCRE
concentration on longitudinal General Cognitive Index (GCI)/Full-Scale
IQ (FSIQ), Verbal IQ (VIQ), and Performance IQ (PIQ) scores (N = 348).
We tested for possible interactions between MUFCRE and child sex as well
as for MUFCRE and time point on children's IQ. All models controlled for
relevant available covariates.
Results: The mean/median MUFCRE concentration was 0.90/0.83 mg/L (SD =
0.39; IQR, 0.64-1.11 mg/L). A 0.5 mg/L increase in MUFCRE predicted an
average 2.12-point decrease in GCI/FSIQ (95% CI:-3.49,-0.75) and
2.63-point decrease in PIQ (95% CI:-3.87,-1.40). MUFCRE was marginally
associated with VIQ across time (B =-1.29, 95% CI:-2.60, 0.01). No
interactions between MUFCRE and child sex or MUFCRE and time were
observed.
Conclusion: The negative association between prenatal fluoride exposure
and longitudinal IQ was driven by decrements in non-verbal intelligence
(i.e. PIQ), suggesting that visual-spatial and perceptual reasoning
abilities may be more impacted by prenatal fluoride exposure as compared
to verbal abilities.
Filiaciones:
Goodman, Carly V.:
York Univ, Fac Hlth, Toronto, ON, Canada
Bashash, Morteza:
Univ Toronto, Dalla Lana Sch Publ Hlth, Toronto, ON, Canada
Green, Rivka:
York Univ, Fac Hlth, Toronto, ON, Canada
Song, Peter:
Univ Michigan, Sch Publ Hlth, Ann Arbor, MI 48109 USA
Peterson, Karen E.:
Univ Michigan, Sch Publ Hlth, Ann Arbor, MI 48109 USA
Schnaas, Lourdes:
Inst Nacl Perinatol, Mexico City, DF, Mexico
Mercado-Garcia, Adriana:
Inst Nacl Salud Publ, Cuernavaca, Morelos, Mexico
Martinez-Medina, Sandra:
Inst Nacl Perinatol, Mexico City, DF, Mexico
Hernandez-Avila, Mauricio:
Inst Nacl Seguro Social, Mexico City, DF, Mexico
Martinez-Mier, Angeles M.:
Indiana Univ, Sch Dent, Indianapolis, IN USA
Tellez-Rojo, Martha:
Inst Nacl Salud Publ, Cuernavaca, Morelos, Mexico
Hu, Howard:
Univ Toronto, Dalla Lana Sch Publ Hlth, Toronto, ON, Canada
Till, Christine:
York Univ, Fac Hlth, Toronto, ON, Canada
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