Study: Research Suggests Inverse Relationship Between ADHD and Literacy, Language Skills
A new study shows an inverse relationship between the polygenic risk for ADHD, and literacy and language skills, regardless of educational attainment.
February 15, 2019
In studying the genetic overlap between attention deficit disorder (ADHD or ADD) and language skills, researchers at Vrije University in Amsterdam have uncovered an inverse relationship between polygenic ADHD risk and multiple reading and/or spelling abilities, as well as phonemic awareness and verbal intelligence.1 In other words, children with a high probability of ADHD are also more likely to have strong reading and writing skills — but weak listening comprehension and non-word repetition skills.
The researchers established a model to interpret the comorbidity of ADHD and reading disabilities, which co-occur largely due to shared genetic influences — that is, both ADHD and reading disabilities share genetic variability with genetically predicted educational attainment. To do this, the researchers assessed the literacy and language-related abilities of children and adolescents reported in the Avalon Longitudinal Study of Parents and Children (ALSPAC), a UK population based cohort.
Initial findings showed that ADHD polygenic scores were inversely related to literacy and language impairments, most consistently with reading impairments. Polygenic links with ADHD were divided into two groups: effects shared with and independent from educational attainment. Further modeling of polygenic links conditional on educational attainment showed an ADHD-specific association profile primarily involving literacy-related impairments. After accounting for shared genetic effects with educational attainment, the risk for polygenic ADHD was most strongly inversely connected to reading and spelling abilities.
The strength of the genetic overlap between literacy and language-related abilities and polygenic ADHD risk may vary depending on ADHD symptom domain levels, especially inattentiveness, the researchers said.
1 iPSYCH-Broad-PGC ADHD Consortium. “Disentangling polygenic associations between attention-deficit/hyperactivity disorder, educational attainment, literacy and language.” Translational Psychiatry, Vol. 9 (2019). https://research.vu.nl/en/publications/disentangling-polygenic-associations-between-attention-deficithyp