Contents lists available at ScienceDirect Psychiatry Research journal homepage: www.elsevier.com/locate/psychres The assessment of serum lipid profiles of children with attention deficit hyperactivity disorder Cagatay Ugur a, ⁎ , Ozden Sukran Uneri a , Zeynep Goker a , Ebru Sekmen a , Hilal Aydemir a , Esra Solmaz b a Child and Adolescent Psychiatry Department, University of Health Sciences, Ankara Child Health and Diseases Hematology Oncology Training and Research Hospital, Sehit Omer Halisdemir Caddesi, Kurtdereli Sokak, No: 10 06100, Diskapi/Ankara Turkey b Child and Adolescent Psychiatry Department, Ankara University Medical School, Ankara Turkey ARTICLE INFO Keywords: ADHD Cholesterol Triglyceride LDL HDL ABSTRACT Attention-deficit/hyperactivity disorder (ADHD) is one of the most prevalent psychiatric disorders in children and the pathophysiology remains obscure. Some studies show that lipid imbalances are associated with ADHD etiology. We studied the association of serum total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglyceride (TG) levels in ADHD. We examined 88 children aged 8–12 years who were diagnosed with ADHD and 88 healthy children. The exclusion criteria were as follows: obesity, any psychotropic use in the last 3 months, presence of a chronic disease and/or malignancy, history of medically treated lipid metabolism disease in family members, intelligence quotient (IQ) < 70, and comorbidities, with the exception of oppositional defiant disorder. The sample was evaluated using a semi-structured clinical assessment interview and Conners' rating scales. Despite controlling for age, sex, and body mass index (BMI) variables, the total cholesterol and LDL levels were significantly higher in the ADHD group than the levels of healthy controls, whereas the TG and HDL cholesterol levels were similar among groups. Conners' rating scales, reflecting symptom severity, and total cholesterol, TG, HDL, and LDL levels of the ADHD group were not correlated. The study results support the difference in serum lipid and lipoprotein profiles of children with ADHD compared with healthy controls. This difference is thought to be related with changes in oxidant/antioxidant balance states in ADHD. 1. Introduction Attention-deficit/hyperactivity disorder (ADHD) is an inherited and early-onset neurodevelopmental disorder of childhood characterised by inattention, hyperactivity, and impulsivity (APA 2013). The frequency of ADHD was reported as 5.29% (Polanczyk et al., 2007). There is an increasing awareness of improvement in symptoms of ADHD during treatment and impairments in social and academic functioning in the absence of treatment. The elucidation of the etiology and pathophy- siology of ADHD is also gaining momentum. Dysregulated dopami- nergic, serotonergic, and noradrenergic neurotransmission have been widely implicated in ADHD etiology, which is thought to be multi- factorial (Lam et al., 2006). Cholesterol is an important constituent of cell membranes and plays a crucial role in the compartmentalisation of the plasma membrane, signalling, synaptogenesis, and brain development (Goritz et al., 2005). Brain cholesterol accounts for a substantial proportion of the body's total cholesterol, existing in two pools: the plasma membranes of neurons and glial cells and the myelin membranes, as an essential molecule for myelination (Petrov et al., 2016; Saher et al., 2005). The cholesterol content in the brain must be accurately maintained to conserve high-level cognitive functions (Zhang and Liu 2015). Brain cholesterol plays a vital role in sustaining the function of neuronal re- ceptors, which are key components in neural signal transduction (Chattopadhyay and Paila 2007). Cholesterol is composed of low-density lipoprotein (LDL), high- density lipoprotein (HDL), and total triglycerides (TG). Increased LDL and TG levels, and decreased HDL levels are associated with an increase in coronary artery disease (Müller et al., 2003). The relationship be- tween serum lipid levels and the serotonergic system was shown in previous studies (Buydens-Branchey et al., 2000; Asellus et al., 2010; Kaplan et al., 1994). Evidence suggests that cholesterol-lowering interventions reduce central nervous system serotonergic activity, and reduced serotonergic https://doi.org/10.1016/j.psychres.2018.04.006 Received 11 September 2017; Received in revised form 8 March 2018; Accepted 2 April 2018 ⁎ Corresponding author. E-mail address: drcagatay85@gmail.com (C. Ugur). Psychiatry Research 264 (2018) 231–235 Available online 07 April 2018 0165-1781/ © 2018 Elsevier B.V. All rights reserved. T Downloaded for Anonymous User (n/a) at ULAKBIM Res Hosp -Ankara Egitim ve Arastirma Hastanesi from ClinicalKey.com by Elsevier on April 17, 2018. For personal use only. No other uses without permission. Copyright ©2018. Elsevier Inc. All rights reserved.