Gender and Injuries Predict Stimulant Medication Use

Abstract Objective: The purpose of this article was to examine whether injuries in early childhood and gender predict prescriptions of stimulant medication in three groups of children: With attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and other psychiatric disorders (OPD). Methods: This was a population-based study with prospective and complete follow-up of children with ADHD (n = 11,553), ASD (n = 9698), and OPD (n = 48,468), of whom 61%, 16%, and 3%, respectively, were treated with stimulants. For all 69,719 individual children data on psychiatric diagnoses, injuries, and drug prescriptions were obtained from national registers and merged. Results: Having sustained an injury before 5 years of age increased the likelihood of later stimulant treatment, in children with ADHD (odds ratio [OR] = 1.09; 95% confidence interval [CI] = 1.01-1.21), ASD (OR = 1.19; 95% CI = 1.02-1.40), and OPD (OR = 1.24; 95% CI = 1.08-1.42), with each injury increasing the likelihood by 3%, 10%, and 7%, respectively. Head injury did not increase the likelihood of later stimulant treatment. Within each of the three groups, ADHD, ASD, and OPD boys were more likely than girls to receive stimulant medication, OR = 1.17 (95% CI = 1.07-1.28); OR = 1.71 (95% CI = 1.47-2.01), and OR = 2.41 (95% CI = 2.16-2.71), respectively. Conclusions: To our knowledge, this is the first prospective study assessing early life predictors of later ADHD medication in children with a psychiatric disorder, taken from a national cohort with complete follow-up of all cases. We found that the number of injuries prior to diagnosis was associated with initiation of stimulant treatment in all three groups of patients. In addition, male gender predicted treatment with ADHD medications. Our results suggest that the number of injuries early in life prior to diagnosis is associated with stimulant treatment, and may serve as a proxy for the level of later severity of ADHD symptoms, as it is universally associated with pharmacological treatment for ADHD

Whole-Body Biodistribution, Dosimetry, and Metabolite Correction of [C]Palmitate: A PET Tracer for Imaging of Fatty Acid Metabolism

Introduction: Despite the decades long use of [ 11 C]palmitate positron emission tomography (PET)/computed tomography in basic metabolism studies, only personal communications regarding dosimetry and biodistribution data have been published. Methods: Dosimetry and biodistribution studies were performed in 2 pigs and 2 healthy volunteers by whole-body [ 11 C]palmitate PET scans. Metabolite studies were performed in 40 participants (healthy and with type 2 diabetes) under basal and hyperinsulinemic conditions. Metabolites were estimated using 2 approaches and subsequently compared: Indirect [ 11 C]CO 2 release and parent [ 11 C]palmitate measured by a solid-phase extraction (SPE) method. Finally, myocardial fatty acid uptake was calculated in a patient cohort using input functions derived from individual metabolite correction compared with population-based metabolite correction. Results: In humans, mean effective dose was 3.23 (0.02) µSv/MBq, with the liver and myocardium receiving the highest absorbed doses. Metabolite correction using only [ 11 C]CO 2 estimates underestimated the fraction of metabolites in studies lasting more than 20 minutes. Population-based metabolite correction showed excellent correlation with individual metabolite correction in the cardiac PET validation cohort. Conclusion: First, mean effective dose of [ 11 C]palmitate is 3.23 (0.02) µSv/MBq in humans allowing multiple scans using ∼300 MBq [ 11 C]palmitate, and secondly, population-based metabolite correction compares well with individual correction