الفهرس 
Attention deficit hyperactivity disorderOnly 14 pages are availabe for public view
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Abstract
Summary
Attention deficit hyperactivity disorder(ADHD) is a highly
heritable neurodevelopmental disorder. It is one of the most
prevalent psychiatric disorders in children and it greatly impairs
social and cognitive functions in affected individuals. It is
characterized by a childhood-onset pattern of hyperactivity,
inattention and impulsivity, that commences in early childhood
and often persists into adulthood.
The current psychiatric disease classification system, DSM-5,
distinguishes three subtypes: a mainly inattentive, a mainly
hyperactive–impulsive and a combined subtype
ADHD occurs in 8-12% of children worldwide and is more
prevalent in males than females. ADHD’s onset occurs around 3
years of age in both sexes. ADHD symptoms usually lessen with
age such that the rate of persistence is only 15% by age 25.
Common comorbidities in children with ADHD include
motor coordination problems, tic disorders, sleep disorders,
specific learning disorders such as dyslexia, and child-psychiatric
disorders such as depression, anxiety, oppositional defiant and
conduct disorders, and autistic spectrum disorders.
ADHD is best seen as a multifactorial disorder in which
genes and environment play a complicated intertwined role.
Multifactorial in this respect implies that the phenotype is due to
Summary
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the combination of multiple genetic as well as environmental
contributors
Children generally develop an amazing number of motor
skills in the first years of their lives. Some of these skills, such as
walking, develop naturally, whereas other skills, such as
swimming and writing require a lot of practice after specific
instruction.
Developmental coordination disorder (DCD) is a marked
impairment in motor coordination which significantly interferes
with academic achievement or activities of daily living. These
deficits in motor skills have been labelled in many ways over the
centuries (e.g., neurological soft signs, clumsiness), but the
current, dominant term is developmental coordination disorder in
young children is more common than generally realized. Children
under the age of 5 years may have difficulties in one or more areas
of development, including speech and language, motor, socialemotional
and cognitive development.
Clinical studies of children with DCD have reported higher
prevalence in boys. Clinical and epidemiological studies report
that 30% to 50% of children with ADHD suffer from motor
coordination problems. Some authors consider DCD as the lowest
extreme end of a continuum of motor performance, others describe
DCD as a categorical disorder, or consider it as the lightest form
of cerebral palsy.
Summary
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Little is known about the etiology of DCD. It is probably best
seen as a multifactorial disorder. In the following section genetic
and environmental risk factors are discussed as well as some
neurobiological and neuro functional deviations associated with
DCD.
DCD often co-occurs with other developmental disorders,
most commonly attention deficit hyperactivity disorder (ADHD).
Up to 50% of children with DCD have been shown also to meet
criteria for ADHD. With recent evidence suggesting a genetic link
between these two disorders, though it has received less attention
in research. Recent clinical and experimental evidence suggests a
greater role of motor factors in ADHD than was considered
before.
Children with (ADHD) and children with Developmental
Coordination Disorder (DCD) appear to share difficulties in
motor, academic, social, and emotional functioning. Children
diagnosed with ADHD are frequently described as clumsy, having
poor coordination, and suffering from poor fine and gross motor
functioning.
The type and degree of movement difficulty differed between
children with ADHD-predominantly inattentive (ADHD-PI) and
ADHD-combined (ADHD-C). Children with ADHD-PI had
significantly poorer fine motor (FM) skills, whereas children with
ADHD-C had significantly greater difficulty with gross motor
(GM) skills. Interestingly, this combination is detected irrespective
of ADHD severity.
Studies that have followed children with DCD and ADHD
(i.e., DAMP) report that these children are at risk for a number of
psychiatric and personality disorders. More than half of the
adolescents with DAMP had psychiatric or personality disorders.
The psychiatric symptoms displayed by these adolescents ranged
from affective and anxiety disorders to personality disorders.
Beyond those associated with either disorder in isolation.
Motor coordination problems are likely important factors
mediating links between ADHD and poor physical activity
outcomes. Children with ADHD tend to have more adipose tissue
and poorer cardiovascular performance than controls.
It remains unclear what exactly is the etiology of the
combination of ADHD and motor coordination problems,
although this relationship has been known to exist for many years.
Neuropsychological and neuro-imaging studies have demonstrated
an underlying neurological substrate for ADHD.
Children with both motor problems and Attention Deficit
Hyperactivity Disorder (ADHD) may require different
interventions from children with ADHD only and that evaluation
of gross motor issues is important in the diagnostic workup of
children with attention and/or activity problems.
Our study showed that Poor Motor coordination is a frequent
coexisting problem in children with ADHD. Also motor
incoordination is more common in inattentive type of ADHD than
hyperactivity and combined type of ADHD. Motor delay was no
significantly correlated with the severity of ADHD.
Our results confirm previous research demonstrating a
consistent relationship between ADHD and poor motor
performance with high levels of motor coordination problems in
ADHD. We found that motor incoordination is more common in
inattentive type of ADHD than hyperactivity and combined type
of ADHD