Dosage of methylphenidate and traumatic brain injury in ADHD: a population-based study in Taiwan

Effect of ADHD medication on risk of injuries: a preference-based instrumental variable analysis

ADHD is associated with an increased risk of injury. Causal evidence for effects of pharmacological treatment on injuries is scarce. We estimated effects of ADHD medication on injuries using variation in provider preference as an instrumental variable (IV). Using Norwegian registry data, we followed 8051 patients who were diagnosed with ADHD aged 5 to 18 between 2009 and 2011 and recorded their ADHD medication and injuries treated in emergency rooms and emergency wards up to 4 years after diagnosis. Persons with ADHD had an increased risk of injuries compared to the general population (RR 1.35; 95% CI: 1.30-1.39), with higher risk in females (RR 1.47; 95% CI: 1.38-1.56) than males (RR 1.23; 95% CI: 1.18-1.28). The between-clinics variation in provider preference for ADHD medication was large and had a considerable impact on patients' treatment status. There was no causal evidence for protective effects of pharmacological treatment on injuries overall for young individuals with ADHD characterized by milder or atypical symptoms. However, there was an apparent effect of pharmacological treatment over time on the risk of injuries treated at emergency wards in this patient group.

Drivers and Barriers to Tolerable and Effective Treatment for ADHD: The Importance of Treatment Perseverance and Duration of Effect

OBJECTIVE

To examine treatment outcomes for classes of ADHD drugs in conjunction with physicians' prescribing rationales and the utility of treatment perseverance in treatment effectiveness.

METHODS

A retrospective non-interventional study using physician-provided chart data for treated adolescent and adult ADHD patients in the United States (April-June 2019). Multivariable analyses compared the effectiveness and tolerability of drug classes.

RESULTS

Among the 1,232 ADHD patients included in this study, 37.7% experienced one, 11.8% two, and 6.7% three treatment changes post their first prescribed regimen. These changes were mostly attributed to lack of rapid onset and duration of effect. Achieving best response correlated with the number of previous treatments for adolescents, but not adults. Maintaining full response correlated with the length of current treatment for adolescents and adults.

CONCLUSION

Physicians' prescribing rationales targeted duration of effect and tolerability. ER monotherapy demonstrated potential advantages over other regimens. Treatment perseverance is integral to effective ADHD management.

Risk of injuries requiring hospitalization in attention deficit hyperactivity disorder and the preventive effects of medication

AIMS

Patients with attention deficit hyperactivity disorder (ADHD) are prone to injury and frequently require treatment with hospital admission. This study aimed to evaluate the risk of injuries requiring hospitalization among children and adolescents with and without ADHD and assess the effects of medication on the risk reduction in patients with ADHD.

METHODS

This is a retrospective population-based cohort study by using data from the Taiwan National Health Insurance Research Database. We compared 4658 6-18 year-old ADHD patients with 18 632 sex-, age-, and index day-matched non-ADHD controls between 2005 and 2012. Both groups were followed until the end of 2013 to compare the risk of injuries requiring hospitalization. Cox regression analysis was performed to determine the hazard ratio (HR) with 95% confidence intervals (CI) after adjusting for confounders.

RESULTS

Children and adolescents with ADHD had a significantly higher risk of injuries requiring hospitalization than the non-ADHD controls (HR = 1.39, 95% CI = 1.12-1.72), and a higher risk was especially observed in the male and adolescent subgroups. In ADHD patients, long-term users of ADHD medication were associated with a lower risk of injuries requiring hospitalization than nonusers (HR = 0.51, 95% CI = 0.30-0.85).

CONCLUSION

Healthcare providers should be aware of the potential risk of injury in patients with ADHD and highlight the importance of the duration and compliance with medication treatment.

Methylphenidate Use and Infectious Diseases in Children With Attention Deficit and Hyperactivity Disorder: A Population-Based Study

Objective

Children with attention deficit hyperactivity disorder (ADHD) have more visits to the emergency department (ED) due to injuries than those without ADHD. However, no study has investigated whether children with ADHD have more ED visits or hospitalizations due to infectious diseases (IDs) and whether methylphenidate (MPH) treatment may reduce the risk.

Method

The incidence of ID-related ED visits or hospitalizations was defined as the main outcome. The Cox regression and conditional Poisson regression models were calculated to estimate hazard ratios (HRs) in the population level and relative risks for the self-controlled case series design, respectively.

Results

Children with ADHD had higher rates of emergency visits (HR = 1.25, 95% CI: 1.23~1.27) and hospitalizations (HR = 1.28, 95% CI: 1.26~1.31) due to IDs than those without ADHD. In the ADHD subgroup, those who received MPH treatment have a reduced risk of emergency visits (HR = 0.10, 95% CI: 0.09~0.10) and hospitalizations (HR = 0.73, 95% CI: 0.71~0.75), compared to those without treatment. The risk of ID-related emergency visits decreased to 0.21 (95% CI: 0.21~0.22); and hospitalizations decreased to 0.71 (95% CI: 0.69~0.73). Within self-controlled analysis, it is demonstrated that compared with non-MPH exposed period, children with ADHD had significantly decreased risks for infection-related emergency visits (RR = 0.73, 95% CI: 0.68~0.78) or hospitalizations (RR = 0.19, 95% CI: 0.17~0.21) during MPH-exposed periods.

Conclusions and Relevance

This is the first study that reported an increased risk of ID-related healthcare utilizations in children with ADHD compared to those without, and that such risks may be significantly reduced in ADHD children that received MPH treatment.

Methylphenidate and TBI in ADHD and co-occurring epilepsy and mental disorders: a self-controlled case series study

It is suggested that medication for attention-deficit hyperactivity disorder (ADHD) links to lower risk of traumatic brain injury (TBI). Little is known about whether the beneficial effect of methylphenidate is persistent in individuals with other comorbid mental disorders and epilepsy. We identified 90,634 participants who were less than 18 years old and diagnosed with ADHD from Taiwan's National Health Insurance Research Database (NHIRD) from January 1, 2000 to December 31, 2013. Cox proportional hazards models with hazard ratio (HR) and 95% confidence interval were conducted to compare the risks of TBI event between groups of ADHD-only and ADHD with co-occurring other mental disorders. Within-individual comparisons using a self-controlled case series study design were conducted using conditional Poisson regression models with relative incidence (RR) and 95% CI to examine the effect of methylphenidate on TBI with adjustment for medication of psychotropics and anticonvulsants. For children and adolescents with ADHD, we found comorbid mental disorders and epilepsy increase the risk of TBI, with HRs ranged from 1.21 to 1.75. For the effect of MPH, we found reduced risks for TBI in ADHD (RR = 0.83, 95% CI = 0.70-0.98). Similar results were found among individuals with co-occurring oppositional defiant disorders or conduct disorder, MDD, tic disorders and epilepsy. Methylphenidate treatment was linked to lower risk for TBI in patients with ADHD and the inverse association was persistent among those with other comorbid mental disorders and epilepsy.

Concussion Incidence and Recovery Among Youth Athletes With ADHD Taking Stimulant-Based Therapy

Background:

Attention deficit hyperactivity disorder (ADHD) may affect concussion risk and recovery in youth athletes.

Purpose:

To evaluate the association between incidence of concussion and postinjury recovery of symptoms and neurocognitive dysfunction among youth athletes with ADHD and differential stimulant use.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

From 2009 to 2019, the authors administered the Immediate Post-concussion Assessment and Cognitive Testing (ImPACT) to youth athletes at the beginning of each season. Throughout the season, athletes with concussions were examined and readministered the ImPACT both postinjury and again 7 days after the postinjury administration. These athletes (N = 7453) were divided into those with ADHD on stimulant-based therapy (ADHD+meds; n = 167), those with ADHD not on stimulant-based therapy (ADHD-only; n = 354), and those with no ADHD (non-ADHD; n = 6932). Recovery of neurocognitive dysfunction at postinjury and follow-up was calculated using the ImPACT symptom score, verbal memory, visual memory, visual motor skills, and reaction time (calculated as standardized deviations from baseline). Univariate results were confirmed with multivariate analysis.

Results:

The ADHD+meds cohort had a lower incidence of concussion (37.3 concussions per 100 patient-years) compared with the ADHD-only group (57.0 concussions per 100 patient-years) (odds ratio [OR], 0.51 [95% CI, 0.37-0.71]; P < .0001) and non-ADHD group (52.8 concussions per 100 patient-years) (OR, 0.50 [95% CI, 0.37-0.67]; P < .0001). At postinjury, ImPACT scores were elevated from baseline to a similar extent in the ADHD+meds cohort compared with the other 2 groups. By follow-up, however, deviations from baseline were lower among the ADHD+meds group compared with the non-ADHD group in verbal memory (OR, 0.46 [95% CI, 0.28-0.76]; P = .002), visual memory (OR, 0.27 [95% CI, 0.10-0.66]; P = .005), and visual motor skills (OR, 0.58 [95% CI, 0.33-0.99]; P = .048). The deviation at follow-up was also lower among the ADHD+meds group compared with the ADHD-only group in visual memory (OR, 0.56 [95% CI, 0.33-0.96]; P = .04) and visual motor skills (OR, 0.42 [95% CI, 0.22-0.81]; P = .01).

Conclusion:

Stimulant use among youth athletes with ADHD was independently associated with reduced incidence for concussion and lower deviation from baseline in verbal memory, visual memory, and visual motor skills at 7 days postconcussion, suggesting lower neurocognitive impairment at follow-up in this group versus their peers.

The World Federation of ADHD International Consensus Statement: 208 Evidence-based conclusions about the disorder

BACKGROUND

Misconceptions about ADHD stigmatize affected people, reduce credibility of providers, and prevent/delay treatment. To challenge misconceptions, we curated findings with strong evidence base.

METHODS

We reviewed studies with more than 2000 participants or meta-analyses from five or more studies or 2000 or more participants. We excluded meta-analyses that did not assess publication bias, except for meta-analyses of prevalence. For network meta-analyses we required comparison adjusted funnel plots. We excluded treatment studies with waiting-list or treatment as usual controls. From this literature, we extracted evidence-based assertions about the disorder.

RESULTS

We generated 208 empirically supported statements about ADHD. The status of the included statements as empirically supported is approved by 80 authors from 27 countries and 6 continents. The contents of the manuscript are endorsed by 366 people who have read this document and agree with its contents.

CONCLUSIONS

Many findings in ADHD are supported by meta-analysis. These allow for firm statements about the nature, course, outcome causes, and treatments for disorders that are useful for reducing misconceptions and stigma.

Effect of medication on risk of traumatic brain injury in patients with bipolar disorder: A nationwide population-based cohort study

BACKGROUND

Increased traumatic brain injury (TBI) risk was found in patients with bipolar disorder (BPD). Whether the medications for BPD and dosage moderate the risk of TBI is not clear.

AIM

This study aimed to determine whether an association exists between BPD and TBI and whether the prescription of psychotropics moderates TBI risk.

METHODS

A total of 5606 individuals who had received diagnoses of BPD between January 1, 1997 and December 31, 2013 and 56,060 matched controls without BPD were identified from Taiwan's National Health Insurance Research Database. Cases and controls were followed until the date of TBI diagnosis.

RESULTS

BPD was associated with a high risk of TBI (adjusted hazard ratio (aHR): 1.85; 95% CI: 1.62-2.11). Patients with BPD, with or without a history of psychiatric hospitalization, had increased risks of TBI (aHR: 1.94, 95% CI: 1.57-2.4 and aHR: 1.82, 95% CI: 1.55-2.1, respectively). The prescription of typical antipsychotics (0 < defined daily dose (DDD) < 28: hazard ratio (HR) = 1.52, 95% CI: 1.19-1.94; ⩾28 DDD: HR = 1.54, 95% CI: 1.15-2.06) and tricyclic antidepressants (TCAs) (0 < DDD < 28: HR = 1.73, 95% CI: 1.26-2.39; ⩾28 DDD: HR = 1.52, 95% CI: 1.02-2.25) was associated with higher TBI risk. Patients receiving higher doses of benzodiazepines (BZDs) (cumulative dose ⩾28 DDD) had a higher TBI risk (HR = 1.53, 95% CI: 1.13-2.06).

CONCLUSION

Patients with BPD have a higher risk of TBI. The use of typical antipsychotics, TCAs, or high-dose BZDs increases the risk of TBI in BPD.

Association of psychiatric comorbidities with the risk of transport accidents in ADHD and MPH

AIMS

Although the relationship between attention-deficit/hyperactivity disorder (ADHD) and transport accidents has been shown, there is limited information on the relationship between medication and dose-response effects and transport accident risk. This study aims to determine whether young people with ADHD, including adolescents, are more prone to transport accidents than those without, and the extent to which methylphenidate (MPH) prescription in these patients reduces the risk.

METHODS

We identified 114 486 patients diagnosed with ADHD from Taiwan's National Health Insurance Research Database from 1997 to 2013. Using a Cox regression model, we compared the risk of transport accidents between ADHD and non-ADHD groups and estimated the effect of MPH on accidents. Furthermore, we applied a self-control case-series analysis to compare the risk of accidents during the medication periods with the same patients' non-medication periods.

RESULTS

Male ADHD patients had a higher risk of transport accidents than non-ADHD individuals (adjusted hazard ratio [aHR] = 1.24, [95% confidence interval (CI) 1.10-1.39]), especially for those comorbid with epilepsy, oppositional defiant disorder/conduct disorder (ODD/CD), and intellectual disabilities (ID). Female ADHD patients showed no relationship, except for comorbid with autism spectrum disorder (ASD) or ID. We found a reduced risk of transport accidents in patients with ADHD with MPH medication than those without MPH, with a plausible dose-response relationship (aHR of 0.23 to 0.07). A similar pattern was found in self-controlled case-series analysis.

CONCLUSIONS

Male patients with ADHD, especially those comorbid with epilepsy, ODD/CD, or ID, were at high risk of transport accidents. Female patients, when comorbid with ASD or ID, also exhibited a higher risk of accidents. MPH treatment lowered the accident risk with a dose-response relationship.

Methylphenidate and the risk of burn injury among children with attention-deficit/hyperactivity disorder

AIMS

Attention-deficit/hyperactivity disorder (ADHD) is associated with a higher risk of burn injury than in the normal population. Nevertheless, the influence of methylphenidate (MPH) on the risk of burn injury remains unclear. This retrospective cohort study analysed the effect of MPH on the risk of burn injury in children with ADHD.

METHOD

Data were from Taiwan's National Health Insurance Research Database (NHIRD). The sample comprised individuals younger than 18 years with a diagnosis of ADHD (n = 90 634) in Taiwan's NHIRD between January 1996 and December 2013. We examined the cumulative effect of MPH on burn injury risk using Cox proportional hazards models. We conducted a sensitivity analysis for immortal time bias using a time-dependent Cox model and within-patient comparisons using the self-controlled case series model.

RESULTS

Children with ADHD taking MPH had a reduced risk of burn injury, with a cumulative duration of treatment dose-related effect, compared with those not taking MPH. Compared with children with ADHD not taking MPH, the adjusted hazard ratio for burn injury was 0.70 in children taking MPH for <90 days (95% confidence interval (CI) 0.64-0.77) and 0.43 in children taking MPH for ≥90 days (95% CI 0.40-0.47), with a 50.8% preventable fraction. The negative association of MPH was replicated in age-stratified analysis using time-dependent Cox regression and self-controlled case series models.

CONCLUSION

This study showed that MPH treatment was associated with a lower risk of burn injury in a cumulative duration of treatment dose-related effect manner.

A literature review and meta-analysis on the effects of ADHD medications on functional outcomes

OBJECTIVE

To conduct a systematic review and meta-analysis of literature from large databases and registries to assess the effects of ADHD medication on associated functional outcomes.

STUDY DESIGN

A literature search was performed in PubMed, PsycINFO, MEDLINE, and Web of Science for articles published prior to January 2019. Sample size, age range, country of origin, medication type, number of functional events and non-events, odds ratios and hazard ratios, and means and standard deviations were extracted. Random-effects meta-analyses were conducted for 21 studies examining functional outcomes.

RESULTS

40 articles were included. The majority suggest a robust protective effect of ADHD medication treatment on mood disorders, suicidality, criminality, substance use disorders, accidents and injuries, traumatic brain injuries, motor vehicle crashes, and educational outcomes. Similarly, the meta-analyses demonstrated a protective effect of medication treatment on academic outcomes, accidents and injuries, and mood disorders.

CONCLUSIONS

These findings suggest that ADHD medication treatments are associated with decreases in the risks for a wide range of ADHD-associated functional outcomes supporting efforts aimed at early diagnosis and treatment of individuals with ADHD.

Decreased Risk of Influenza in Child and Adolescent Patients with Attention-Deficit Hyperactivity Disorder Following Methylphenidate Treatment: A Nationwide Cohort Study in Taiwan

BACKGROUND

Young individuals with attention-deficit hyperactivity disorder (ADHD) may have an elevated risk of influenza because of the difficulty in complying with the behavioral procedures that help protect against influenza. Moreover, the effects of sufficient methylphenidate treatment on influenza have received little attention.

OBJECTIVE

This study evaluated the association between ADHD medication usage and influenza and assessed the effect of duration of ADHD treatment on the risk of influenza using a nationwide population-based database.

METHODS

This study investigated methylphenidate usage and the risk of influenza among children and adolescents with ADHD. We identified 5259 young individuals aged less than 18 years who were diagnosed as having ADHD between 1996 and 2013 from the National Health Insurance Research Database of Taiwan, and we tested whether methylphenidate use affects influenza risk using Cox proportional hazard models.

RESULTS

After controlling for confounding factors, the results indicated that influenza risk significantly reduced in the group of ADHD patients who were prescribed methylphenidate for 90 days and more (hazard ratio [HR]: 0.62, 95% confidence interval [CI]: 0.52-0.75, p<0.001), demonstrating a 38% reduction in the risk of influenza in this group. However, this was not observed in the group of ADHD patients who used methylphenidate for 1-90 days (HR: 0.69, 95% CI: 0.89-1.05, p=0.12).

CONCLUSION

The lower incidence of influenza observed in the group prescribed with methylphenidate for a longer period highlights the importance of compliance to medication and psychoeducation with regard to ADHD management.

Risks and Benefits of Attention-Deficit/Hyperactivity Disorder Medication on Behavioral and Neuropsychiatric Outcomes: A Qualitative Review of Pharmacoepidemiology Studies Using Linked Prescription Databases

Attention-deficit/hyperactivity disorder (ADHD) medication is one of the most commonly prescribed medication classes in child and adolescent psychiatry, and its use is increasing rapidly in adult psychiatry. However, major questions and concerns remain regarding the benefits and risks of ADHD medication, especially in real-world settings. We conducted a qualitative systematic review of studies that investigated the effects of ADHD medication on behavioral and neuropsychiatric outcomes using linked prescription databases from the last 10 years and identified 40 studies from Europe, North America, and Asia. Among them, 18 used within-individual designs to account for confounding by indication. These studies suggested short-term beneficial effects of ADHD medication on several behavioral or neuropsychiatric outcomes (i.e., injuries, motor vehicle accidents, education, substance use disorder), with estimates suggesting relative risk reduction of 9% to 58% for these outcomes. The within-individual studies found no evidence of increased risks for suicidality and seizures. Replication studies are needed for several other important outcomes (i.e., criminality, depression, mania, psychosis). The available evidence from pharmacoepidemiology studies on long-term effects of ADHD medication was less clear. We discuss time-varying confounding and other limitations that should be considered when interpreting results from pharmacoepidemiology studies. Furthermore, we highlight several knowledge gaps to be addressed in future research and implications for research on mechanisms of outcomes of ADHD medications.

Attention-Deficit/Hyperactivity Disorder and Mortality Risk in Taiwan

IMPORTANCE

Few studies have investigated levels of mortality in patients with attention-deficit/hyperactivity disorder (ADHD), and findings have been inconsistent and lacking information on specific causes of deaths.

OBJECTIVE

To investigate the association between ADHD and causes of death in Taiwan.

DESIGN, SETTING, AND PARTICIPANTS

A nationwide population-based cohort study was conducted using a cross-national Taiwanese registry. The ADHD group comprised 275 980 individuals aged 4 to 44 years with a new diagnosis between January 1, 2000, and December 31, 2012. All individuals with ADHD were compared with 1 931 860 sex- and age-matched controls without ADHD.

EXPOSURES

The association between ADHD and mortality was analyzed using a Cox regression model that controlled for sex, age, residence, insurance premium, outpatient visits, congenital anomaly, intellectual disability, depression disorder, autism, substance use disorder, conduct disorder, and oppositional defiant disorder. The analysis of suicide, unintentional injury, homicide, and natural-cause mortality was performed by a competing risk adjusted Cox regression controlling for other causes of mortality and potential confounding factors.

MAIN OUTCOMES AND MEASURES

Data on mortality from all causes, suicide, unintentional injury, homicide, and natural causes collected from a national mortality database.

RESULTS

There were 275 980 individuals with ADHD and 1 931 860 comparison individuals without ADHD in this study. Sex and age at index date were matched. The mean (SD) age was 9.61 (5.74) years for both groups. Most of the participants were male (209 406 in the ADHD group; 1 465 842 in the non-ADHD group; 75.88% for both groups). A total of 4321 participants from both cohorts died during the follow-up period (15.1 million person-years), including 727 (0.26%) from the ADHD group and 3594 (0.19%) from the non-ADHD group. Of those who died, 546 (75.1%) in the ADHD group and 2852 (79.4%) in the non-ADHD group were male. After adjusting for potential confounders, compared with the non-ADHD group, patients with ADHD showed higher overall mortality (adjusted hazard ratio, 1.07; 95% CI, 1.00-1.17) and higher injury-cause mortality from suicide (adjusted hazard ratio, 2.09; 95% CI, 1.62-2.71), unintentional injury (adjusted hazard ratio, 1.30; 95% CI, 1.10-1.52), and homicide (adjusted hazard ratio, 2.00; 95% CI, 1.09-3.68). No increased risk of natural-cause mortality was observed after adjustment.

CONCLUSIONS AND RELEVANCE

In this study, ADHD was associated with higher injury-cause mortality, particularly that due to suicide, unintentional injury, and homicide. Although the risk of injury mortality was significantly higher in patients with ADHD than in the non-ADHD group, the absolute risk of mortality was low.

The Association Between Attention-Deficit Hyperactivity Disorder, Injuries, and Methylphenidate

Objective. To evaluate the relationship between attention-deficit hyperactivity disorder (ADHD) and injuries and to verify whether methylphenidate (MPH), is associated with decreasing the risk of injuries. Methods. A retrospective cohort study using the computerized database of Maccabi Healthcare Services. The ADHD cohort included all children between 12 and 20 years of age, newly diagnosed with ADHD between 2003 and 2013. The comparison cohort was composed of children who were not diagnosed with ADHD. The primary outcome was traumatic injuries. A Cox proportional hazard regression analysis was conducted to estimate ADHD effects on the risk of injuries. We also conducted a nested case-control study to examine how MPH influences this relationship. Results. A total of 59 798 children were included in the cohort study; 28 921 were classified as exposed (ADHD cohort) and 30 877 were unexposed. The traumatic injuries incidence in the exposed group was significantly higher (adjusted hazard ratio = 1.63 [95% confidence interval = 1.60-1.66]). Similar increased risk was documented also for severe injuries (adjusted hazard ratio = 1.72 [1.59-1.86]). MPH use was significantly associated with 28% lower injury events. Therapy groups were significantly associated with 29% to 40% lower injuries rate for medium- or long-acting MPH. The intensity of therapy was significantly associated with 29% to 33% lower injury rate when the intensity was lower than 0.69 mg/kg/day. Conclusion. Children with ADHD have a 60% increased odds of experiencing an injury. Treatment with MPH reduced the risk by up to 28%. The individual and financial cost secondary to injuries, underscores the public health significance of this problem. Injury prevention should be considered in clinical evaluation of MPH risks and benefits, beyond the conventional consideration of enhancing academic achievements.

Treatment strategies for ADHD: an evidence-based guide to select optimal treatment

Attention-deficit/hyperactivity disorder (ADHD) is a common and impairing disorder affecting children, adolescents, and adults. Several treatment strategies are available that can successfully ameliorate symptoms, ranging from pharmacological to dietary interventions. Due to the increasing range of available options, an informed selection or prioritization of treatments is becoming harder for clinicians. This review aims to provide an evidence-based appraisal of the literature on ADHD treatment, supplemented by expert opinion on plausibility. We outline proposed mechanisms of action of established pharmacologic and non-pharmacologic treatments, and we review targets of novel treatments. The most relevant evidence supporting efficacy and safety of each treatment strategy is discussed. We review the individualized features of the patient that should guide the selection of treatments in a shared decision-making continuum. We provide guidance for optimizing initiation of treatment and follow-up of patients in clinical settings.