The offspring of older fathers show subtle impairments on tests of neurocognitive ability during infancy and childhood

Offspring of Older Fathers May Have Subtle Neurocognitive Impairments


Laurie Barclay, MD


March 18, 2009 — The offspring of older fathers show subtle impairments on tests of neurocognitive ability during infancy and childhood, according to the results of a study reported in the March 10 issue of PLoS Medicine.

"Advanced paternal age (APA) is associated with an increased risk of neurodevelopmental disorders such as autism and schizophrenia, as well as with dyslexia and reduced intelligence," write Sukanta Saha, from Queensland Centre for Mental Health Research, The Park Centre for Mental Health, in Richlands, Australia, and colleagues. "The aim of this study was to examine the relationship between paternal age and performance on neurocognitive measures during infancy and childhood."

The study sample consisted of 33,437 singleton children enrolled in the US Collaborative Perinatal Project. At ages 8 months, 4 years, and 7 years, these children underwent testing with the Bayley scales, Stanford Binet Intelligence Scale, Graham-Ernhart Block Sort Test, Wechsler Intelligence Scale for Children (WISC), and Wide Range Achievement Test. The primary analyses evaluated the association between neurocognitive measures and paternal or maternal age, after adjustment for potential confounding factors.

On all the neurocognitive measures, except for the Bayley Motor score, advanced paternal age correlated significantly with poorer scores. At all 3 ages tested, the findings were broadly consistent in direction and effect size. In contrast, there was an association between advanced maternal age and generally better scores on these same tests.

"The offspring of older fathers show subtle impairments on tests of neurocognitive ability during infancy and childhood," the study authors write. "In light of secular trends related to delayed fatherhood, the clinical implications and the mechanisms underlying these findings warrant closer scrutiny."

Limitations of this study include nonrandom sample attrition and missing data that could affect the generalizability of the results; cohort members born in the United States during the 1960s, limiting generalizability to more contemporary cohorts; and neurocognitive outcomes only determined until age 7 years.

"While most of the neurocognitive differences were small at the individual level, these could have important implications from a public health perspective," the study authors conclude.

The study authors have disclosed no relevant financial relationships.

PLoS Med. 2009;6:e40.