Metylfenidats effekt och säkerhet hos barn och ungdomar med ADHD

Sammanfattning: Introduction: ADHD (Attention Deficit Hyperactivity Disorder) is a congenital disability that involves difficulties with concentration, hyperactivity and impulsivity. The cause of ADHD is not entirely understood, but a number of risk factors are known with heredity considered as the most important of them.  The number of children, adolescents and adults who have been diagnosed with ADHD has increased in recent years in Sweden. While the frequency of ADHD diagnosis has increased, prescription of ADHD drugs has also increased, mainly methylphenidate, which is usually first-line treatment, and also has been prominent since 2006. The mechanism of action of methylphenidate in ADHD is not fully known but the substance is believed to act by increasing the amount of dopamine and noradrenaline in the synapses by inhibiting the reuptake to the presynaptic neuron. With the help of brain imaging techniques, it has been possible to detect abnormalities in the brain's function in people with ADHD, which are specifically located in the frontal lobe. The deficiencies in the impulse transmission in parts of the brain that stimulate activity regulation, impulse control and attention causes the typical ADHD symptoms.  Purpose: To investigate the effect and safety of long-acting methylphenidate (OROS- MPH) in children and adolescents with ADHD.  Method: This work is a literature study where five scientific articles were selected from the database PubMed through the keywords OROS methylphenidate AND children with ADHD.  Results: Children and adolescents who participated in the studies were diagnosed with ADHD according to the DSM-IV criteria (Diagnostical and Statistical Manual of Mental Disorders). The studies varied between 6 weeks and 3 months. ADHD symptoms were mainly measured with ADHD-RS-IV, CGI, SNAP-IV, IOWA Conners Behavior Rating Scale and the Permanent Product Math Test (PERMP). All studies showed that OROS-MPH significantly improved ADHD symptoms compared to placebo. In Study 1, when comparing OROS-MPH with lisdexamphetamine, lisdexamphetamine produced a significantly greater effect than OROS-MPH on both the ADHD-RS-IV scale and CGI-I scale in the forced-dose study (p=0,0013) but not in the flexible-dose study (p=0,0717). Participants also performed better with the use of OROS-MPH compared with placebo in academic (PERMP, SKAMP) and cognitive tests (TOVA, Finger windows subtest, Digit Span Test) regardless of the presence of comorbid learning disability. The most common side effects were decreased appetite, decreased weight, headache, dry mouth, insomnia and abdominal pain. Discussion & conclusion: The effect of methylphenidate in these studies were assessed with slightly different diagnostic scales but for all the scales, significant effect was demonstrated when OROS-MPH was compared with placebo. Treatment with OROS-MPH proved to be safe and generally well tolerated. Most of the side effects were mild to moderate and two serious side effects were seen in two participants. However, more studies are needed to determine the long-term effects of OROS-MPH as all studies were of short duration and treatment can last for many years.