22q11.2 Deletion Syndrome: Cognitive, Visuomotor, and Adaptive Functioning Followed Longitudinally

Longitudinal studies on cognitive, visuomotor, and adaptive function and their relation to outcomes in adults with the 22q11.2 deletion syndrome (22q11.2DS) are limited.

This study involved 79 participants (43 females, 36 males) from an original cohort of 100 individuals (58 females, 42 males) with 22q11.2DS, assessed at ages 1-35 years between 1997 and 2006 (T1) and followed up in 2017-2022 (T2), when they were aged 18-50. Clinical, neuropsychological, and adaptive functioning assessments were performed.

At the group level, overall Full-Scale Intelligence Quotient (FSIQ) remained stable; however, females displayed a significant decline in FSIQ and visuomotor integration (Beery VMI) from T1 to T2. At follow-up, 19 of 56 (34%) participants had an uneven intelligence quotient (IQ) profile, with most (15/56; 27%) showing a higher Verbal Function Index (VFI) than Perceptual Function Index (PFI). At T1, 10 of 49 participants (20%) had this "uneven IQ profile," defined as having a higher VFI than PFI (Verbal Comprehension Index [VCI] ≥15 IQ points higher than Perceptual Reasoning Index [PRI]), compared to 14 of 49 (29%) at T2. In the psychosis subgroup (n = 8), FSIQ and Verbal Intelligence Quotient (VIQ) showed significant decreases; however, the small sample size limits the validity of these findings. Severe to moderate adaptive function impairments, as measured by the Global Assessment of Functioning (GAF) scale, were observed at T2, with T1 FSIQ predicting GAF at T2.

While group-level intellectual functioning appeared stable, individual declines were noted. Long-term follow-up is essential for personalized support to mitigate severe psychiatric risks, including psychosis with declines in FSIQ, particularly VIQ, potentially indicating or resulting from psychosis in this population.