Basics
Description
Learning disabilities (LD) are a group of disorders characterized by unexpected and sustained difficulties acquiring and applying academic skills, including reading accuracy, reading fluency, reading comprehension, written expression, mathematic calculations, and mathematic problem-solving.
- LD comprise one category within the classification of Neurodevelopmental Disorders (NDDs) in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-V, 2013) and the International Classification of Diseases, Code Book 10 (ICD-10, 2013).
- Academic achievement must be substantially below the level expected for age and not attributable to intellectual disability (ID), neurologic or motor disorders, lack of schooling, psychosocial factors, economic disadvantage, or major sensory problems.
- LD have neurobiologic and genetic roots.
- Reading disability is the most frequently diagnosed type of LD and is typically characterized by impairments in phonologic processing and/or orthographic coding skills. Children with math disability show procedural, retrieval, and number sense deficits.
- The role of the pediatrician is to advocate for a child with LD, interpret predisposing factors in child 's developmental and medical history, and offer scientific interpretation of the range of theories and interventions.
- Early intervention improves outcomes.
Epidemiology
- In 2009 " 2010, 2.4 million or 5% of total public school enrollees (ages 3 " 21 years) identified with LD as eligible for special education based on U.S. Department of Education National Center for Education Statistics, 2012.
- The National Institutes of Health (NIH) estimates that as many as 15 " 20% of Americans are affected by LD.
Risk Factors
- LD are familial and moderately heritable.
- Risk loci and genes have been identified for reading and language disorders.
- Aberrant neuronal migration hypothesized as principal pathophysiology
- Genetic contribution increases with a high level of parent education (a bioecologic gene by environment interaction).
- Environmental factors include prematurity, low birth weight, prenatal nicotine or alcohol exposure, infections, and traumatic brain injury.
Commonly Associated Conditions
- Language disorders
- Speech sound disorders
- Auditory processing disorders
- Developmental coordination disorder
- ADHD/executive function deficits
General Prevention
- High-quality developmentally appropriate preschool experiences
- Early literacy initiatives (e.g., Reach Out and Read)
- Early intervention for speech, language, motor difficulties
- Evidence-based reading curricula and ongoing academic progress monitoring beginning in kindergarten
- Supplemental instruction for children who show early signs of learning problems
Diagnosis
Differential Diagnosis
- ID
- Borderline intellectual functioning or mild ID may not be evident in early childhood.
- ADHD
- Especially when inattentive and distractible symptoms are greater than hyperactive symptoms
- Comorbidity is approximately half of diagnosed cases of LD.
- Sensory impairments
- Hearing or vision impairments
- School screening results should be confirmed by the pediatrician in children with academic problems.
- Neurologic etiologies
- Absence seizures and other nonconvulsive epileptic disorders
- Neurodegenerative disorders such as Niemann " Pick disease, adrenoleukodystrophy, ceroid lipofuscinosis, and subacute sclerosing panencephalitis may rarely present as school-age learning problems.
- CNS trauma
- Genetic syndromes
- Some genetic syndromes may show subtle dysmorphology that is not noted until learning problems arise. Examples include the following:
- Sex chromosome aneuploidies
- Fragile X syndrome
- Neurofibromatosis
- Tuberous sclerosis
- Velocardiofacial/DiGeorge syndrome
- Hypothyroidism
- HIV infection
- Lead intoxication
- Chronic malnutrition
- Iron deficiency
- Iatrogenic interventions
- Some medications (e.g., antiepileptic drugs) affect cognition.
- Cancer treatment
- Psychosocial issues
- Issues related to family stress, peer relationships, illness, school absence, or adolescence may present as academic difficulty.
- Conversely, behavior problems at home or at school always should prompt evaluation of school functioning.
- Psychiatric comorbidity
- Adjustment disorders, anxiety, mood disorders, oppositional defiant disorder, conduct disorder, tic disorders, substance abuse, and other behavior problems may precede or follow the presentation of LD.
Approach to the Patient
- Many learning problems respond to appropriate educational interventions, regardless of specific etiology, and failure to respond to intervention is part of the diagnostic process for specific LD.
- It is the role of the educator to (a) monitor academic progress of all students, (b) provide educational intervention and frequent progress monitoring to struggling students, and (c) conduct a psychoeducational assessment of students who do not respond to initial intervention.
- Once a child presents with learning problems, it is the role of the pediatrician to
- Help the family obtain timely and evidence-based educational interventions. LD Navigator (http://www.ncld.org) provides health care professionals with resources.
- Identify and treat underlying medical problems.
- Identify and help treat underlying psychosocial issues:
- Psychosocial stresses may exacerbate learning difficulties or be a primary etiologic factor.
- School attendance is a particularly important factor in learning.
- Identify and treat comorbid psychiatric disorders.
History
- Question: When and how does the child fail in his or her daily academic pursuits?
- Significance:
- LD typically impact only school activities and are often limited to one skill area such as reading or math.
- Children with ADHD typically show problems in multiple settings (school, home, extracurricular, peers).
- Children with ID usually have a history of developmental concerns.
- Question: Is decline in school performance recent and/or abrupt?
- Significance: If abrupt, consider pathophysiologic processes such as vision or hearing impairment, side effect from medication, neurodegenerative disorders (rare), or recent psychosocial issue.
- Question: Past medical history, medications, review of systems, psychosocial stresses?
- Significance
- School attendance (illness vs. avoidance)
- Early development and behavior
- Family history of learning problems
- Sleep patterns (apnea, insomnia)
Physical Exam
- Finding: Subtle dysmorphology?
- Significance: May suggest the presence of a genetic syndrome or a pattern of malformation resulting from teratogenic fetal exposures (e.g., alcohol, phenytoin)
- Finding: Skin lesions?
- Significance: May suggest underlying genetic syndromes such as tuberous sclerosis
- Finding: Enlarged tonsils?
- Significance: May cause sleep disturbance that affects learning and/or behavior
- Finding: Abnormal neurologic examination?
- Significance
- Any focal signs demand additional evaluation
- Slow rapid alternating finger movements (neuromaturational signs) are often present in children with LD but are generally not helpful clinically.
Diagnostic Tests & Interpretation
- Physician
- Audiology and vision screening
- Standardized behavior questionnaires (e.g., Teachers and Parent Vanderbilt)
- Consider other screening tools for depression, anxiety, family dysfunction, parental depression, and substance abuse.
- Genetic, neurologic evaluation if indicated by history or physical exam
- Educator
- Teacher-administered measures or computer-administered tests to monitor progress. Standardized achievement tests can be administered yearly to measure current functioning and review progress.
- Psychologist
- Testing must be performed individually and include intellectual and academic functioning at a minimum.
- Federal law requires schools to provide comprehensive evaluations on written request by the parents. Specific information for each state is available from the National Dissemination Center for Children with Disabilities (800-695-0285; http://www.nichcy.org).
- University- and hospital-based centers outside the school system also conduct evaluations of children with LD.
- For children who do not respond to educational interventions, or if the psychoeducational evaluation is inconclusive, neuropsychologic testing may identify specific cognitive factors that are helpful in developing an effective educational plan.
Treatment
- Discourage a "wait and see " approach to decision making.
- Begin evidence-based interventions as soon as problems are evident; children who do not respond require more thorough etiologic workup.
- Academic or attention difficulties may lead to spiraling psychological problems from depression or damaged self-esteem to conduct disorder and school dropout.
General Measures
- Physician
- Responsible for treatment of underlying medical diagnoses
- Ensure appropriate treatment of psychological problems with pharmacologic therapy and behavioral therapy (family therapy, social skills training, cognitive-behavioral therapy) as needed.
- School
- Educational treatment varies with the age and educational level of the child and should follow an approach of increasing intensity as needed.
- Tier 1: For patients displaying poor academic achievement, begin with extra support (e.g., homework clinic, tutoring) in the regular educational program (assuming culturally and linguistically appropriate instruction).
- Tier 2: If academic problems disrupt classroom participation and impede progress, refer to school-based child study team and provide intensive assistance as part of general curriculum, such as summer school or specialized materials.
- Tier 3: If child is >1 year behind or has shown minimal response to Tier 2 interventions, refer for a comprehensive psychoeducational evaluation to identify specialized interventions, typically provided under the umbrella of special education.
- Specialized instruction is at the center of treatment, often within the regular classroom (inclusion) with supplemental instruction through either a consultant special teacher or a resource room.
- Children may also benefit from classroom accommodations such as preferential seating, extra time for test taking, word processors and computer applications, text-to-speech programs, calculators, note-takers, and modified instructions.
- Treatment is most effective when it uses a team approach, including parents, teachers, and other therapists.
- Grade retention has not been shown to be effective.
Ongoing Care
Children with LD require continued monitoring of academic progress. Even when the initial learning problems are resolved, later difficulties may arise in writing, note-taking, composition, organization, or with more abstract academic subjects.
Prognosis
- In most cases, prognosis is quite good with treatment, although LD never go away.
- Prognosis varies with intensity, timing, and appropriateness of intervention.
- Early diagnosis and treatment is essential for minimizing impact and to take advantage of typical developmental progression.
- Current brain imaging research shows remedial reading instruction alters brain functioning if provided during critical window of development (younger than age 8 " 10 years).
Additional Reading
- American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). Arlington, VA: American Psychiatric Association; 2013.
- Catts HW, Nielsen DC, Bridges MS, et al. Early identification of reading disabilities within an RTI framework. J Learn Disabil. 2013;20:1 " 17.
- Olulade OA, Napoliello EM, Eden GF. Abnormal visual motion processing is not a cause of dyslexia. Neuron. 2013;79(1):180 " 190. [View Abstract]
- Peterson RL, Pennington BF. Developmental dyslexia. Lancet. 2012;379(9830):1997 " 2007. [View Abstract]
- Raskind WH, Peter B, Richards T, et al. The genetics of reading disabilities: from phenotypes to candidate genes. Front Psychol. 2013;3:601. [View Abstract]
- World Health Organization. International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10). Geneva, Switzerland: World Health Organization; 1992.
Codes
ICD09
- 315.2 Other specific developmental learning difficulties
- 315.00 Developmental reading disorder, unspecified
- 315.1 Mathematics disorder
- 315.09 Other specific developmental reading disorder
- 315.02 Developmental dyslexia
- 315.35 Childhood onset fluency disorder
- 315.34 Speech and language developmental delay due to hearing loss
- 315.31 Expressive language disorder
- 315.01 Alexia
- 315.39 Other developmental speech disorder
ICD10
- F81.9 Developmental disorder of scholastic skills, unspecified
- F81.0 Specific reading disorder
- F81.2 Mathematics disorder
- F81.89 Other developmental disorders of scholastic skills
- F80.9 Developmental disorder of speech and language, unspecified
- F80.1 Expressive language disorder
- F81.81 Disorder of written expression
SNOMED
- 1855002 developmental academic disorder (disorder)
- 52824009 Developmental reading disorder (disorder)
- 47916000 Developmental arithmetic disorder (disorder)
- 192575009 Mixed disorder of scholastic skills (disorder)
- 45677003 developmental expressive writing disorder (disorder)
- 443735008 Nonverbal learning disorder (disorder)
FAQ
- Q: What is the evidence that visual training will improve reading?
- A: Despite anecdotal reports of value, there is strong evidence that visual dysfunction is not causal to reading disability; there is insufficient evidence to recommend vision therapy.