Prospective follow-up studies found no chromosomal mutagenicity of methylphenidate therapy in ADHD affected children

In silico molecular docking and in vitro analysis of atomoxetine

Although atomoxetine, a selective norepinephrine reuptake inhibitor, is widely used in the treatment of attention-deficit/hyperactivity disorder (ADHD), there is limited data on its cytogenetic effects. This study aimed to investigate the cytotoxicity and genotoxicity of atomoxetine in vitro and silico. Chromosome aberration and micronucleus assays were used to analyze the genotoxic effect of atomoxetine in human peripheral blood lymphocytes under culture conditions. The mitotic index was assessed for cytotoxic potential. For the docking analysis, DNA receptor (1BNA) was prepared with ChimeraX, and the Atomoxetine molecule was optimized by Avogadro2.0 software. In silico molecular docking analysis was carried out utilizing SwissDock online platform. The results obtained were visualized using ChimeraX and Pymol software. Atomoxetine doses of 9.6 µg/mL (equal to about 1.2 mg/kg as a maintenance dose), 14.4 µg/mL (equal about to 1.8 mg/kg as the highest dose systematically tested), 48.0 µg/mL (equal about to 6 mg/kg as five times the maintenance dose) and 96.0 µg/mL (equal about to 12 mg/kg as ten times the maintenance dose) were analyzed. The findings clearly indicate that atomoxetine has no genotoxic effect at the therapeutic dose. However, we observed genotoxic effects at 48.0 and 96.0 µg/mL doses. No strong binding affinity occurs in silico analyses. As one of the initial inquiries into the in silico and in vitro appraisal of atomoxetine's genotoxic impacts, the research has established that atomoxetine does not significantly affect the frequency of chromosomal damage or micronucleus formation. Genotoxic effects should be kept in mind at doses above clinical practice.

Factors Affecting the Nuclei in Newborn and Children

It is known that children are more sensitive to the effects of medical treatments and environment than adults. Today there is limited information regarding the differences in genotoxic effects in children. The micronucleus assay is a method that is used to monitor genotoxicity, and it was validated several years before. Today there is international interest for exfoliated buccal cells. Most of the micronuclei studies in children have been performed with the analyses of lymphocytes. However, there is vast interest in using exfoliated cells from the oral cavity. The reason is that other type of cells are acquired non-invasively, this is an important issue in paediatric cohorts. Unfortunately a limitation of measuring micronuclei frequency is that it has been observed to be low in newborns and on the other hand there are a large number of patients and cell sample counts. It has been observed that radiation exposure and environmental pollutants increase the micronuclei frequency in newborn and children. Regarding the medical treatments, there is little data and several studies are needed to optimise the doses. There is the need to observe if there is a relationship between micronuclei in lymphocytes and exfoliated cells and to identify the baseline of the micronuclei levels. Moreover, we evaluate the changes in response to the toxic agents. Prospective cohorts studies will clarify the predictive value of micronuclei for cancer and chronic diseases for both children and adults. Novel molecular technologies will assist in the elucidation of different biological pathways and molecular mechanisms connected with the micronulcei levels in newborn and children.

Psychiatric and Nonpsychiatric Comorbidities Among Children With ADHD: An Exploratory Analysis of Nationwide Claims Data in Germany

Objective: This study examined the full spectrum of comorbid disorders in all statutory-health-insured children aged 5 to 14 years with ADHD in 2017 by using nationwide claims data in Germany. Method: Children with ADHD (n = 258,662) were compared for the presence of 864 comorbid diseases with a control group matched by gender, age, and region of residence (n = 2,327,958). Results: Among others, metabolic disorders (odds ratio [OR] = 9.18; 95% confidence interval [CI] = [8.43, 9.99]), viral pneumonia (OR = 4.95; 95% CI = [2.37, 10.33]), disorders of white blood cells (OR = 4.55; 95% CI = [3.83, 5.40]), kidney failure (OR = 3.33; 95% CI = [2.65, 4.18]), hypertension (OR = 3.26; 95% CI = [3.00, 3.55]), obesity (OR = 2.85; 95% CI = [2.80, 2.91]), type 2 diabetes (OR = 2.61; 95% CI = [2.11, 3.23]), migraine (OR = 2.49; 95% CI = [2.37, 2.61]), asthma (OR = 2.19; 95% CI = [2.16, 2.22]), atopic dermatitis (OR = 2.10; 95% CI = [2.16, 2.23]), juvenile arthritis (OR = 1.56; 95% CI = [1.39, 1.76]), glaucoma (OR = 1.51; 95% CI = [1.30, 1.75]), and type 1 diabetes (OR = 1.30; 95% CI = [1.20, 1.40]) were more likely to be diagnosed in ADHD children. Conclusion: Along with psychiatric diseases, various somatic diseases were more common in ADHD children. The results have direct implications for patient care, including fine-grained diagnostics and personalized therapy.

The association between medication for attention-deficit/hyperactivity disorder and cancer

OBJECTIVE

A study on chromosomal abnormalities has raised concerns that medication with methylphenidate (MPH) for attention-deficit/hyperactivity disorders (ADHD) might increase the risk of cancer. We performed a rigorous test of the association between cancer and MPH and other drugs used for ADHD, based on data from nationwide Danish registers.

METHODS

Data were linked from five registers containing information on a total of 21,186 patients with ADHD, their drug prescription rates, and associated cancer diagnoses between 1994 and 2010. The cohort included subgroups treated with MPH only, amphetamines only, other ADHD-specific drugs only, antidepressants only, antipsychotics only, mixed medication, and a control group of patients with ADHD who had never taken medication. Frequencies of cancer diagnoses in these groups were compared. In addition, hazard risk (HR) ratios for developing cancer, and survival rates in these subgroups, were analyzed.

RESULTS

The mean observation time varied between 1.3 and 10.8 years for the various drugs. Cancer rates in the total group amounted to 1.27 per 10 000 person-years before and to 4.33 per 10 000 person-years after onset of treatment. The frequency of cancer was significantly higher (p = 0.05) after than before medication only in the antipsychotics subgroup. Furthermore, for mixed medication, the cancer frequency in a small subgroup was significantly higher (p < 0.05) after onset of medication than in the unmedicated subgroup. The Cox regression analysis indicated that none of the drugs represented risk factors, whereas higher dose (p < 0.001) and older age (p < 0.05) were risk factors for developing cancer.

CONCLUSIONS

The concern that children taking MPH and other drugs over long periods of time could be at a significant risk of developing cancer is not substantiated by these findings in a large and representative sample, which had been diagnosed and treated over a period of 17 years.

Pharmacologic intervention for attention-deficit hyperactivity disorder in preschoolers : is it justified?

Pharmacologic intervention for attention-deficit hyperactivity disorder (ADHD) in preschool children is a controversial issue. Non-pharmacologic interventions (psychosocial and restricted dietary interventions) have been shown to benefit oppositional, non-compliant, aggressive and disruptive, as well as hyperactive and inattentive behaviors in preschoolers with ADHD and other disruptive behavior disorders. However, not all families have access to non-pharmacologic interventions or prefer them. The Preschool ADHD Treatment Study recently provided evidence of benefit with immediate-release methylphenidate; however, effect sizes were small to moderate and preschoolers had a high rate of adverse effects and a unique adverse effect profile. Furthermore, no information is available about long-term safety and effects of psychopharmacologic agents on the rapidly developing brains of preschoolers. Based on current evidence and guidelines, a careful trial with psychopharmacologic agents is indicated to treat ADHD in preschoolers if there is no improvement with behavior therapy and the preschoolers continue to exhibit significantly impaired hyperactive and inattentive symptoms. Preschoolers should be monitored closely for adverse effects and tried off medications after 6 months to assess the need for ongoing psychopharmacologic intervention. Further research is needed to identify predictors and moderators of response to guide individualized/optimal treatment options for ADHD in preschoolers.

The genetic toxicity of methylphenidate: a review of the current literature

Attention deficit/hyperactivity disorder (ADHD), a common children's behavioral disorder, is characterized by inattention, hyperactivity and impulsivity. The disorder is thought to stem from abnormalities in the catecholamine pathway and the symptoms of the disorder have been successfully treated with methylphenidate (MPH) since the FDA approved the drug in the 1950s. MPH underwent the appropriate safety testing as part of the FDA approval process; however, a publication in 2005 that reported significant increases in cytogenetic damage in the lymphocytes of MPH-treated pediatric patients caused concern for patients and their families, the pharmaceutical industry and regulatory agencies. This communication will review the many studies that were subsequently initiated worldwide to address the genetic safety of MPH in both animal models and human subjects. Animal experiments broadened the study protocols used in the 2005 investigation to include a wider dose-range, a longer treatment period and automated scoring of biological endpoints, where possible, to reduce observer bias. The human subject studies replicated the experimental design used in the 2005 study, but increased the treatment periods and the sizes of the study populations. Neither the laboratory animal nor human subject studies found an increase in any of the measures of genetic damage that were evaluated. Taken together, these new studies are consistent with the original safety evaluation of the FDA and do not support the hypothesis that MPH treatment increases the risk of genetic damage in ADHD patients. Published 2012. This article is a US Government work and is in the public domain in the USA.

Micronuclei in neonates and children: effects of environmental, genetic, demographic and disease variables

Children may be more susceptible to the effects of the environmental exposure and medical treatments than adults; however, limited information is available about the differences in genotoxic effects in children by age, sex and health status. Micronucleus (MN) assay is a well established method of monitoring genotoxicity, and this approach is thoroughly validated for adult lymphocytes by the Human Micronucleus Biomonitoring project (HUMN.org). Similar international undertaking is in progress for exfoliated buccal cells. Most of the MN studies in children are focused on analyses of lymphocytes but in the recent years, more investigators are interested in using exfoliated cells from the oral cavity and other cell types that can be collected non-invasively, which is particularly important in paediatric cohorts. The baseline MN frequency is relatively low in newborns and its assessment requires large cohorts and cell sample counts. Available results are mostly consistent in conclusion that environmental pollutants and radiation exposures lead to the increase in the MN frequency in children. Effects of medical treatments are less clear, and more studies are needed to optimise the doses and minimise genotoxicity without compromising therapy outcomes. Despite the recent progress in MN assay in children, more studies are warranted to establish the relationship between MN in lymphocytes and exfoliated cells, to clarify sex, age and genotype differences in baseline MN levels and the changes in response to genotoxicants. One of the most important types of MN studies in children are prospective cohorts that will help to clarify the predictive value of MN and other cytome end points for cancer and other chronic diseases of childhood and adulthood. Emerging 'omic' and other novel molecular technologies may shed light on the molecular mechanisms and biological pathways associated with the MN levels in children.