Preliminary Investigation of Association between Methylphenidate and Serum Growth Markers in Children with Attention-Deficit/Hyperactivity Disorder: A Cross-Sectional Case-Control Study

Effect of methylphenidate on height in pediatric attention-deficit hyperactivity disorder patients: a systematic review and meta-analysis

Methylphenidate (MPH), a first-line treatment for attention-deficit hyperactivity disorder (ADHD) management, has been the focus of debate for decades regarding its effect on growth. The aim of this PRISMA meta-analysis was to determine the effect of MPH on height in children/adolescents with ADHD and its predictive factors based on literature reports. Available full-text articles were systematically reviewed to identify clinical studies of pediatric ADHD patients with height Z-score (HZS) data for monotherapy MPH-treated and non-treated groups. We estimated standardized mean differences (SMDs) of HZS or its changes from baseline (ΔHZS) between groups, then identified associated factors through subgroup analyses and meta-regression. For before-after treatment studies, the paired standard errors of ΔHZS were re-estimated to demonstrate in the forest plot. Risk of bias was analyzed using the Newcastle-Ottawa Scale. Among the 29 eligible studies, 26 reported ΔHZS with self-control groups, and ΔHZS or absolute HZS were compared to other external controls in 11 studies. A significant reduction was observed between post-MHP and pre-MPH use, with high heterogeneity (SMD =  - 0.40; 95% confidence interval = [ - 0.54,  - 0.27]; I2 = 91%). The study region, ADHD subtype, and stimulant-naïve status of patients at baseline may modify the effect on HZS. Because of the high clinical heterogeneity in observational studies, clinicians should consider the negative effect of MPH on height in ADHD patients by determining whether patients fulfill appropriate high-risk criteria. Further well-designed longitudinal studies are required to better quantify this effect, especially with prolonged treatment.

Analysis of Serum VEGF, IGF-1, and HIF-1α Levels in ADHD

OBJECTIVE

In recent years, it has been emphasized that various growth factors that affect neurogenesis may lead to ADHD. In this study, we aimed to investigate the role of VEGF, IGF-1, and HIF-1α growth factors in the etiopathogenesis of ADHD.

METHOD

Levels of VEGF, IGF-1, and HIF-1α were compared between 40 ADHD children and 40 healthy children, aged 7 to 13 years.

RESULT

VEGF, IGF-1, and HIF-1α levels did not significantly differ between the groups. There was a negative correlation between serum VEGF levels and the parent-rated T-DSM-IV-S (AD) subscale. There was a positive correlation between serum IGF-1 levels and the parent-rated T-DSM-IV-S (AD) subscale, and SDQ (ES) subscale.

CONCLUSION

Given our limitations and the fact that some of our findings differ from those of other studies, it is evident that this area requires additional research with larger samples.

Effect of Atomoxetine on Behavioral Difficulties and Growth Development of Primary School Children with Attention-Deficit/Hyperactivity Disorder: A Prospective Study

(1) Objective: Atomoxetine is a selective norepinephrine reuptake inhibitor used to treat attention-deficit/hyperactivity disorder (ADHD) in children over six years old. Although it is common knowledge that primary school children with ADHD often present with difficulties in the morning prior to school and in the evening, these two periods, and the family interactions they involve, are often neglected in studies of ADHD. Questionnaire–Children with Difficulties (QCD) has been widely used in China to evaluate parents’ perceptions of ADHD and patients’ daily behaviors during different times. In the long term, the efficacy and safety of atomoxetine have been well established in previous studies. Still, the short-term effects of atomoxetine treatment on serum growth parameters, such as IGF-1, IGFBP-3, and thyroid function, are not well documented. Therefore, this study was the first one using the QCD to quantify the efficacy of atomoxetine treatment in the morning prior to school and in the evening, and has investigated the possible influence on the growth parameters of Chinese primary school children with ADHD. (2) Method: This prospective study was conducted at the Department of Pediatrics at the Affiliated Hospital of Jiangnan University from August 2019 to February 2021. Changes in the children’s behavior and core ADHD symptoms following treatment were assessed using three parent-reported questionnaires, including Children with Difficulties (QCD), the Swanson, Nolan, and Pelham IV scale (SNAP-IV), and the Conners’ parents rating scales (CPRS). The height, weight, and body mass index (BMI) were measured and corrected to reflect the standard deviations (SDS) in Chinese children based on age and gender. Serum growth parameters, such as insulin-like growth factor 1 (IGF-1), insulin-like growth factor-binding protein 3 (IGFBP-3), and thyroid function, were also measured to assess the children’s growth development. Any adverse drug reactions were assessed every three weeks. (3) Result: Finally, 149 children were enrolled in this study, and they completed 12 weeks of atomoxetine treatment. The QCD results indicated that the atomoxetine treatment could significantly alleviate behavioral difficulties in primary children with ADHD, especially in the morning prior to school (p < 0.001, r = 0.66) and in the evening (p < 0.001, r = 0.73). A statically significant decrease in weight SDS (p < 0.05) was noted during treatment, but the effect size was slight (r = 0.09). The atomoxetine treatment had no significant impact on height SDS, BMI SDS, and serum growth parameters, such as the levels of IGF-1, IGFBP-3, and thyroid function. The SNAP-IV results showed a significant improvement in the core symptoms of ADHD, while the CPRS results indicated a significant improvement in controlling ADHD symptoms across two different domains, learning problems (r = 0.81) and hyperactivity (r = 0.86). No severe adverse reactions were observed in the course of treatment, and the most common adverse reactions were gastrointestinal symptoms. (4) Conclusions: Atomoxetine is an effective and safe treatment for primary school children with ADHD. In China, it may be an excellent choice to alleviate parenting stress and improve the condition of primary school children with ADHD. Moreover, our study indicated that the serum levels of IGF-1 and IGFBP-3 were within the normal range in newly diagnosed ADHD children, and atomoxetine will not affect the serum concentration of growth parameters, such as IGF-1, IGFBP-3, and thyroid function, in the short term. However, the treatment may reduce appetite, resulting in a reduction in the Children’s weight for a short period. Further observational studies to monitor the long-term effects of atomoxetine on primary school children are recommended.

Interrelationships among growth hormone, thyroid function, and endocrine-disrupting chemicals on the susceptibility to attention-deficit/hyperactivity disorder

Abnormal growth hormones and thyroid function may be linked to pathophysiology of attention-deficit/hyperactivity disorder (ADHD). Phthalates and bisphenol-A (BPA), two endocrine-disrupting chemicals (EDCs), may affect the human endocrine system. In this study, we aimed to perform a comprehensive investigation of whether growth hormone, thyroid function, and EDCs exhibited differential levels between ADHD patients and healthy controls. In total, 144 children with ADHD and 70 healthy control subjects were enrolled. Their endocrine systems were evaluated using the serum levels of insulin-like growth factor-1 (IGF-1), IGF-binding protein-3 (IGFBP-3), thyroid-stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), and Free T4. The urinary levels of EDCs, including monoethyl phthalate (MEP), mono-methyl phthalate (MMP), monoethylhexyl phthalate (MEHP), mono-n-butyl phthalate (MnBP), monobenzyl phthalate (MBzP), and BPA, were also examined. Patients with ADHD had lower IGF-1 levels than healthy controls (p = 0.003), but we observed no significant difference in IGFBP-3, TSH, T3, T4, or Free T4. Compared to the control group, patients with ADHD demonstrated higher MEHP levels (p = 0.043), MnBP (p = 0.033), and MBzP (p = 0.040). Furthermore, MEHP levels (p < 0.001) and BPA levels (p = 0.041) were negatively correlated with IGF-1 levels, while IGF-1 levels were negatively correlated with principal components consisting of ADHD clinical symptoms and neuropsychological performance variables. We suggest that MEHP exposure may be associated with decreased serum levels of IGF-1 and increased risk of ADHD. The mechanism underlying this association may be important for protecting children from environmental chemicals that adversely affect neurodevelopment.

Effects of methylphenidate on height, weight and blood biochemistry parameters in prepubertal boys with attention deficit hyperactivity disorder: an open label prospective study

Background: Adverse effects of stimulants on growth in children have long been studied, but the results remain to be clarified, because metabolic changes or predictors accompanying the growth deviations were not sufficiently studied. Objective: This open label-prospective study investigated the effects of methylphenidate (MPH) on weight, height, blood biochemistry in children with attention deficit hyperactivity disorder (ADHD). Method: Prepubertal boys treated with MPH in Child and Adolescent Psychiatry Clinic at Antalya Training and Research Hospital in Health Sciences University, Turkey were recruited. Height and weight z-scores and fasting blood samples were taken at baseline and 6^th month. Changes were compared by paired-samples t-test or Wilcoxon signed-rank test. Any association between the changes in growth and biochemical values was analyzed by Spearman's Rank-Order Correlation. The statistical significance threshold was p<0.01. Results: 31 boys aged 74 to 104 months were enrolled in the study sample (mean=87.6, Standard Deviation (SD)=9.2). Osmotic release oral system-MPH (18 mg/day) was used in 77.4% (N=24) and immediate release-MPH (5 mg three times a day) in 22.5% (N=7). Average daily drug dose was 0.66 mg/kg (SD=0.12). Baseline weight z-score was 0.63 (SD=1.12), decreased significantly at 6 months (0.24 [SD=1.04]) (Z=-4.44, p=0.000, r=0.5) (median z-score was 0.53 at baseline, -0.11 at 6 months). Baseline height z-score (0.23[SD=0.87]) was not suppressed significantly at 6 months (0.28[SD=0.85])(t(30) = ‒1.50, p=0.14). Glucose (t(30) = -4.33, p=0.000, r=0.6), creatinine (t(30)=-3.28, p=0.003, r=0.5) and 25OH-VitD (N=29, Z=-3.98, p=0.000, r=0.5) increased but alkaline phosphatase (ALP) decreased (t(28)=3.63, p=0.001, r=0.5). The differences in W-SDS and ALP were positively correlated (r=0.47, p=0.009). Conclusions: Our results indicate the importance of monitoring blood variables that may accompany growth changes early in MPH treatment and should be further assessed in larger samples.