Neurodevelopmental comorbidity profile in specific learning disorders

Abstract

Background: Specific learning disorders (SLD) are the common reasons for referral of an otherwise healthy child from a main stream school. Although children do have difficulties even in early learning years in pre-primary and primary school; a significant number of preadolescent children from mainstream school do present with such disabilities. Primary objective was to study the differential distribution of various comorbidities across SLD spectrum. Secondary objective was to check for prevalence of abnormal neurological examination findings including soft signs. Methods: After approval of institutional ethics committee, 100 consecutive case records of children presenting to the center were studied. Diagnosis was confirmed as per DSM V criteria. The clinical, psychological and neurological information was derived from notes of pediatrician, after SLD certification. Details about history, ADHD and comorbidities if any were recorded from parents where documented information was not sufficient. The prevalence of comorbidities was expressed as a percentage of total cases studied. Results: ADD of combined type was the commonest comorbidity seen in 53% cases. Other occasional comorbidities noted were epilepsy, autism, cerebral palsy, history of meningitis and febrile seizures. Speech and visuospatial skills were affected 10% and 41% in children with SLD and all of these had ADD. Soft neurological signs like astereognosis, graphesthesia, dysdiadochokinesia, dysmetria were seen in more than 20% cases. Abnormal antenatal and perinatal history was more common in ADHD with SLD. Conclusions: SLD children from mainstream schools usually have ADHD as commonest comorbidity. Often they should be looked for various neurological comorbidites like autism, epilepsy, cerebral palsy. Soft signs and motor delay need not be overlooked in view of comprehensive management. A large multicentric study is needed to look for soft neurological signs; neuroimaging may be needed in SLD to understand the disorders in cognitive spectrum.