Recently my good friend Isabelle Rapin brought to my attention an article published in the Journal of Autism and Developmental Disorders. The article was conducted by Dr. Rubin Jure from Cordoba, Argentina and was entitled, “Autism Spectrum Disorders (ASD) in Blind Children: Very High Prevalence, Potentially Better Outlook”. Dr. Jure has no formal academic affiliations and undertook this project based on personal observations in children that he had seen in his solo practice of Child Neurology. Dr. Jure conceived the study and conducted the same on his own and only after its completion decided to consult with Dr. Rapin.
The study was based on an unselected sample of 38 children at a school for the blind. Half of the children (n=19) had an autism spectrum diagnosis (ASD). The high prevalence of ASD in the blind is well known in the literature and may account, to a certain degree, as to why a significant percentage of individuals with congenital rubella manifest an autism phenotype.
The results of series detailing a correlation between ASD and blindness suggest that autistic phenotype is not dependent on the cause of the blindness but to the fact that the latter is complete and congenital in origin. What appears startling is that many of the blind children who exhibit ASD: 1) do not exhibit a gender bias, and 2) may lose their diagnosis with time. In a series by Hobson and Lee (2010) 8 of 9 blind children lost their ASD diagnosis when re-evaluated as adolescents. Dr. Jure’s review of 12 published studies totaling 859 early blinded children indicates the staggering prevalence of 48%. ASD as a comorbidity is peculiar to this sensory abnormality and not, for example, to deafness.
The authors of the article discuss some of the reasons why this high correlation has not received more attention in medical literature:
1) Childhood blindness is the least prevalent (0.33%) of all developmental disabilities. Furthermore, only ophthalmologists and specialized clinicians are able to take care of these children.
2) Attending clinicians feel compelled to identify the major incapacitating symptom. Autism in this regard takes a back seat to blindness.
3) There is an unawareness that the correlation exists primarily for congenital total lack of vision beyond light perception and not the etiology of the blindness. Some series of blind individuals may not comply with these observations and their heterogeneous population may not yield the indicated high prevalence rates.
4) Physicians may be reluctant to discuss a second disabling diagnosis with parents of a blind child. They may think it might inflict more pain and suffering on the parents.
The blueprint of connectivity of the brain of a blind individual is different from that of a typically developing child. It is posited that the plasticity ingrained in further rewiring the brain of a blind individual may confer some type of advantage that improves the outlook of autism, some children thus losing their diagnosis during adolescence.
In their conclusions the authors state:
“The time has come for professionals to be aware of congenital blindness (CB) universal consequences for brain structure and function, enabling them to help parents understand the unique and profound brain and experiential consequences of congenital lack of vision. They also need to explain to parents of all children affected by an ASD that it is not a “disease” but defines a particular group of behavioral symptoms of variable severity with differing pathophysiologies depending on its cause. They need to emphasize that ASD in congenital blindness has special characteristics and that all else being equal, the outlook for abatement of autistic symptoms may be somewhat better, long term, in some CB children than sighted children. Pediatricians and other professionals, cognizant of the high risk of ASD in CB, must be on the lookout and make sure blind babies and children’s development is followed closely and that they are provided with optimal social and intellectual nurturing from birth to prevent or remediate them if there are premonitory or overt ASD symptoms. For researchers CB/ASD provides unique investigative opportunities and ideas for research models, some of which may spill over into better understanding and management of all children with ASD.”
A Spanish version translated from the English version by Alexia Rattazzi MD can be obtained from alexiapanaacea@gmail.com
References
Hobson RP, Lee A. Reversible autism among congenitally blind children? A controlled follow-up study. Journal of Child Psychology and Psychiatry and Allied Disciplines, 51(11):1235-1241, 2010.
Jure R, Pogonza R, Rapin I. Autism Spectrum Disorders (ASD) in Blind Children: very High Prevalence, Potnetially Better Outlook, JADD 46:749-759, 2016.