[Response With Methylphenidate to ADHD-Like Symptoms in Pervasive Developmental Disorder: Does CES-1 Enzyme Gene Polymorphism Have a Role?]

Objective: Methylphenidate is the first-choice medication for the Pervasive Developmental Disorders (PDDs), and comorbid Attention Deficit Hyperactivity Disorder (ADHD). But this approach generally results with poor outcomes, and increased adverse effects. It is aimed to investigate the comparison of cases who diagnosed with PDDs and Mild Mental Retardation (MR) and cases with pure ADHD in terms of the clinical response to MPH. Also we aimed to investigate the relations between CES-1 polymorphism gene and the clinical response to MPH.
Methods: For clarifying this we searched for three polymorphisms (Arg199/His, Ser75/Asn, and Ile49/Val) in carboxylesterase-1 gene (CES-1) in the saliva of patients diagnosed with PDD+ADHD. Also, we assessed the clinical response to MPH by dimensional approach using the Attention Deficit Hyperactivity Disorder Rating Scale IV and Clinical Global Impression-Improvement scale.
Results: PDD+ADHD groups had significantly higher Arg199/His polymorphism, and clinically responded poorer with symptoms sometimes even worsening to the MPH treatment compared with "pure" ADHD and ADHD+MR groups.
Conclusion: This is the first study that an association between Arg199/His polymorphism in CES1 and altered treatment response to MPH in patients with PDD that presents with symptoms of ADHD.