Attention-Deficit/Hyperactivity Disorder Medication Treatment Impact on Response to Growth Hormone Therapy: Results from the ANSWER Program, a Non-Interventional Study

The effect of methylphenidate on the dopamine and growth hormone response to exercise in children with attention-deficit hyperactivity disorder

PURPOSE

To assess the growth hormone (GH) and Dopamine (DA) response to exercise in children with attention-deficit hyperactivity disorder (ADHD) with and without methylphenidate (MP). We hypothesized that the GH and DA response to the exercise with MP would be siginicantly lower.

METHODS

Twenty children participated in the study (12 males and 8 females, age range 9-13 years). Ten with ADHD and 10 controls. Participants with ADHD performed an exercise test twice, with and without MP while controls performed one exercise test. Blood samples for GH and DA were collected before, at peak, 30 and 60 min after the end of exercise.

RESULTS

Compared to controls, children with ADHD with and without MP, had a significantly lower GH (P < .002) and DA (P < .01) responses to exercise. In participants with ADHD, a significantly greater GH response (p < .04) to exercise was found when MP administered to the children before exercise, yet this response was still significantly lower than controls.

CONCLUSIONS

GH and DA excretion after an exercise challenge in children with ADHD is impaired. MP slightly attenuates the GH blunted response. This may link ADHD with growth impairment in some children and explain previous findings indicating that the final adult height is usually not compromised in children with ADHD treated with MP. The combined exercise and stimulant treatment therapeutic effects needs to be further explored.

TRIAL REGISTRATION NUMBER

NCT00945971.

Early GH Treatment Is Effective and Well Tolerated in Children With Turner Syndrome: NordiNet® IOS and Answer Program

CONTEXT

Despite having normal growth hormone (GH) secretion, individuals with Turner syndrome (TS) have short stature. Treatment with recombinant human GH is recommended for TS girls with short stature.

OBJECTIVE

This work aimed to evaluate the effectiveness and safety of Norditropin (somatropin, Novo Nordisk) with up to 10 years of follow-up in children with TS.

METHODS

Secondary analysis was conducted of Norditropin data from 2 non-interventional studies: NordiNet® IOS (NCT00960128) and the ANSWER program (NCT01009905).

RESULTS

A total of 2377 girls with TS were included in the safety analysis set (SAS), with 1513 in the treatment-naive effectiveness analysis set (EAS). At the start of treatment, 1273 (84%) participants were prepubertal (EAS); mean (SD) age was 8.8 (3.9) years. Mean (SD) dose received at the start of GH treatment was 0.045 (0.011) mg/kg/day (EAS). Mean (SD) baseline insulin-like growth factor-1 (IGF-I) SD score (SDS) was -0.86 (1.52), and mean (SD) duration of GH treatment (SAS) was 3.8 (2.8) years.Height SDS (HSDS) increased throughout follow-up, with near-adult HSDS reached by 264 (17%) participants (mean [SD] -1.99 [0.94]; change from baseline +0.90 [0.85]). During the study, 695 (46%) participants (EAS) entered puberty at a mean (SD) age of 12.7 (1.9) years (whether puberty was spontaneous or induced was unknown). Within the SAS, mean IGF-I SDS (SD) at year 10 was 0.91 (1.69); change from baseline +1.48 (1.70). Serious adverse reactions were reported in 10 participants (epiphysiolysis [n = 3]).

CONCLUSION

GH-treated participants with TS responded well, without new safety concerns. Our real-world data are in agreement with previous studies.

Reduced exercise-induced growth hormone secretion among children with attention-deficit hyperactivity disorder

PURPOSE

Attention-deficit/hyperactivity disorder (ADHD) is typically a chronic, often lifelong condition. Data suggest that ADHD itself and its treatment may be associated with dysregulated growth, including height and BMI. The reason for this association is yet unknown. The objective of this study was to examine differences in growth hormone (GH) response to exercise between children who had received a diagnosis of ADHD and age- and gender-matched controls. We reasoned that the normal increase in circulating GH seen in response to exercise would be blunted in children with ADHD.

METHODS

We recruited 13 treatment-naïve children with newly diagnosed ADHD and 14 age-matched controls (all male) and measured GH response to an exercise test in which the work was scaled to each subject's physical capability.

RESULTS

There was no difference in the peak heart rate achieved during exercise between controls and ADHD participants (196.6 ± 1.5 vs. 196.5 ± 2.1 bpm, respectively) and lactate response to exercise (53.8 ± 5.0 vs. 47.9 ± 3.8 mg/dl, respectively). After exercise, GH increased significantly in the control subjects (p < 0.005), while GH responses were substantially blunted in the ADHD group (p = NS) even though the work performed did not differ from controls.

CONCLUSIONS

Our data suggest that GH excretion after exercise challenge in children with ADHD is impaired. This can be detected using a minimally invasive, nonpharmacologic challenge and may link ADHD with growth impairment in some children.

TRIAL REGISTRATION NUMBER

NCT00945971.

Predictors of Changes in Height, Weight, and Body Mass Index After Initiation of Central Nervous System Stimulants in Children with Attention Deficit Hyperactivity Disorder

OBJECTIVE

To identify predictors of changes in height, weight, and body mass index (BMI) in children with attention deficit hyperactivity disorder (ADHD) starting central nervous system (CNS) stimulants.

STUDY DESIGN

There were 230 medication-naïve children aged 5-12 years with ADHD who participated in a randomized trial evaluating the impact of CNS stimulants on growth over 30 months. This observational analysis focused on the 141 participants using study medication for 65 or more days in the first 6-months after starting medication. Biometric variables, ADHD, and oppositional defiant disorder symptom scores at medication initiation, and medication use over the study were examined as predictors of changes in standardized (z) height, weight, and BMI.

RESULTS

Mean changes in z-BMI, z-weight. and z-height were negative throughout the study. The most consistent predictors of change in z-BMI, z-weight, and z-height were percent days medicated and total medication exposure. Children with lower z-height and z-weight at medication initiation experienced greater z-BMI and z-weight decreases over the first 6 months on medication. Greater appetite suppression during dose optimization predicted greater decreases in z-weight over the entire study and a greater decrease in z-height over the first 6 months on medication. z-weight change correlated with z-height change. Behavioral symptoms did not predict changes in z-BMI, z-weight, or z-height.

CONCLUSIONS

How much and how often CNS stimulants are used predicts changes in z-BMI, z-weight, and z-height in children. Even smaller and lighter children may be at risk for decreases in z-weight and z-BMI. Parent ratings of appetite during dose titration may serve as feasible indicators of future weight and height change in children using CNS stimulants.

TRIAL REGISTRATION

Clinicialtrials.gov: NCT01109849.

[Effect of Psychosocial Factors on Growth]

BACKGROUND

Genes, hormones and factors such as nutrition and psychosocial environment affect growth.

OBJECTIVE

What is the significance of various psychosocial factors on growth?

METHODS

Evaluation of results of a working meeting of paediatric endocrinologist with current literature research.

RESULTS

Psychosocial deprivation in children can be associated with growth hormone deficiency (GHD) and short stature. GHD can be reversed by a change of environment and psychosocial support. War and migration are often associated with underweight, growth disturbances and poor health care. These factors can improve after the end of conflicts, but children often remain too short. Consumption of alcohol or opiates during pregnancy are associated with lower birth weight and increased risk of early and small for gestational age (SGA) childbirth. Children with attention deficit hyperactivity disorder show a slight slowdown in growth after they started stimulant therapy. However, they reach normal adult height.

CONCLUSIONS

In children with idiopathic short stature, psychosocial causes should be taken into account in the differential diagnosis. Notably there is an increased risk of growth disturbances in children from conflict regions or after prenatal drug exposure.

Treatment of Children With GH in the United States and Europe: Long-Term Follow-Up From NordiNet® IOS and ANSWER Program

CONTEXT

Understanding real-world prescribing of GH may help improve treatment of eligible patients.

OBJECTIVE

Overall: to assess real-world effectiveness and safety of GH (Norditropin). This analysis: to compare clinical characteristics of GH-treated children in the United States and Europe.

DESIGN

The American Norditropin Studies: Web-Enabled Research Program (ANSWER; 2002 to 2016, United States) and the NordiNet International Outcome Study (NordiNet IOS; 2006 to 2016, Europe) were multicenter longitudinal observational cohort studies.

SETTING

Data were recorded in 207 (United States) and 469 (Europe) clinics.

PARTICIPANTS

Patients with GH deficiency, Turner syndrome, Noonan syndrome, idiopathic short stature, Prader-Willi syndrome, or born small for gestational age, who commenced GH treatment aged <18 years.

INTERVENTION

GH was prescribed by treating physicians according to local practice.

MAIN OUTCOMES MEASURES

Baseline data and drug doses were recorded. Data on effectiveness and safety were collected.

RESULTS

ANSWER had 19,847 patients in the full analysis set (FAS; patients with birthdate information and one or more GH prescription) and 12,660 in the effectiveness analysis set (EAS; GH-naive patients with valid baseline information). NordiNet IOS had 17,711 (FAS) and 11,967 (EAS). Boys accounted for 69% (ANSWER) and 57% (NordiNet IOS). Treatment start occurred later than optimal to improve growth. The proportion of boys treated was generally larger, children were older at treatment start, and GH doses were higher in the United States vs Europe. No new safety signals of concern were noted.

CONCLUSIONS

In most indications, more boys than girls were treated, and treatment started late. Earlier diagnosis of GH-related disorders is needed. The data support a favorable benefit-risk profile of GH therapy in children.

Growth perturbations from stimulant medications and inhaled corticosteroids

Stimulant medications for the treatment of attention deficit hyperactivity disorder (ADHD) and inhaled corticosteroids (ICS) for the treatment of asthma are two classes of medications that are commonly prescribed in pediatrics. Among other adverse effects of these medications, growth attenuation has long been a focus of investigation. With stimulants, growth deficits of 1-1.4 cm/year have been observed in the short term, mainly in the first 2 years of treatment, in a dose-dependent manner. Long-term studies on stimulants have reported divergent effects on growth, with many studies showing no clinically significant height deficits by adulthood. The study that followed the largest cohort of children on stimulants, however, reported an overall adult height deficit of 1.29 cm in subjects who had received stimulant medications, with mean adult height deficit of 4.7 cm among those taking the medication consistently. With ICS use, mild growth suppression is seen in the short term (particularly in the first year of therapy) with growth rates reduced by 0.4-1.5 cm/year. Available current evidence indicates that the impact of ICS use on adult height is not clinically significant, with effects limited to 1.2 cm or less. There is significant individual variability in growth suppression with ICS use, with the specific pharmacologic agent, formulation, dose exposure, age, puberty, medication adherence, and timing of administration being important modifying factors. Based on currently available evidence, the therapeutic benefits of ICS for management of asthma and stimulant medications for management of ADHD outweigh the potential risk for growth suppression. Strategies to minimize growth attenuation and other potential adverse effects of these medications include using the lowest efficacious dose, frequent assessments and dose titration. Particular vigilance is essential with concomitant use of multiple medications that can attenuate growth and to evaluate for potential adrenal insufficiency from ICS use.