Attention/Deficit Hyperactivity Disorder in Adolescent and Young Adult Males With Fragile X Syndrome.

Klusek et al. (2022) asked how many older males with fragile X syndrome also meet ADHD criteria.

They gave 16- to 24-year-olds a full DSM-5 interview and the parent checklist called the CBCL.

The team then compared the two tools to see if they caught the same cases.

Forty-two percent of the young men qualified for an ADHD diagnosis.

The CBCL and the DSM interview only agreed about half the time, so many cases were missed when the checklist was used alone.

Luckasson et al. (2020) followed younger boys with FXS for three years and saw that early ADHD signs predicted later autism traits.

That work hints that catching ADHD sooner might soften later social problems.

Eussen et al. (2016) showed these attention and self-control gaps are already clear when boys are only 3-7 years old, so the picture is steady across age.

Farrant et al. (1998) found 15% of adults with severe ID met ADHD criteria, far below the 42% seen here, underlining that FXS carries a uniquely high adult risk.

If you serve teens or adults with fragile X, do not rely on a broadband checklist alone. Add a brief DSM-based ADHD screen to your intake. Spotting the diagnosis opens access to stimulant trials, organizational coaching, and transition planning that can keep jobs and college on track.