Children with uncorrectable vision problems are almost twice as likely to receive a diagnosis of attention deficit/hyperactivity disorder (ADHD) than children with normal vision, according to a retrospective study from researchers at the University of Birmingham, Alabama, School of Medicine. Lead author Dawn DeCarlo, OD, with the school’s Department of Ophthalmology, and colleagues had noticed many children seen in their clinic for impaired vision also had an ADHD diagnosis. After determining that the prevalence of ADHD was indeed higher among visually impaired children at the clinic, the researchers confirmed the suspected association using data from the 2011/2012 National Survey of Children’s Health (NCSH).
The NCSH is a randomized telephone survey that the US Centers for Disease Control and Prevention (CDC) and the National Center for Health Statistics (NCSH) periodically administer to parents to gather information on children’s physical and mental health. For the current study, researchers analyzed data pertaining to more than 75,000 children aged 4 to 17 included in the 2011/2012 NCSH. The survey asked parents whether a health care provider had ever told them their child had a vision problem that was not correctable with glasses or contact lenses and, if so, whether the problem was mild, moderate, or severe. Parents were also asked whether their child had an ADHD diagnosis and, if they said yes, how severe it was.
Approximately 1000 children out of 75,000 (1.5%) had uncorrectable vision problems. An estimated 16% of children with vision problems had a current ADHD diagnosis compared with 8% of children whose vision was normal (P <.001). Children with vision problems accounted for almost 3% of all those with current ADHD. Only children with mild to moderate vision problems had an increased risk of an ADHD diagnosis; these children were also more likely to have more severe ADHD. The authors did not find an increased risk of ADHD among children with severe vision problems, which they said could be because the population was small.
Misdiagnosis may explain the increased prevalence of ADHD in children with uncorrectable vision problems. “It could be as simple as children with vision problems being mislabeled as ADHD because they are not able to pay attention to things they cannot see,” DeCarlo said in an interview. Children with ADHD have impaired executive functioning, and DeCarlo said another possible reason for the association is that children with uncorrected vision problems “are using so much of their executive functioning ability to compensate for their vision impairment that they do not have an adequate reserve of executive functioning capacity to maintain or change additional states.”
DeCarlo said further research is needed, looking specifically for links between ADHD and specific types of vision impairment and for underlying associations. She recommends additional scrutiny for children with uncorrectable vision problems and concurrent ADHD. “If a child with vision problems has symptoms of ADHD, be sure that all of their vision needs are addressed through proper eye care and vision rehabilitation. If those symptoms persist, refer for evaluation by an expert in attention disorders,” she said.
DeCarlo DK, Swanson M, McGwin G, Visscher K, Owsley C. ADHD and vision problems in the National Survey of Children’s Health. Optom Vis Sci. 2016;93:459-465.