Mild head injury and attention deficit hyperactivity disorder in children

Paediatric traumatic brain injury and attention-deficit/hyperactivity disorder medication in Finland: a nationwide register-based cohort study

BACKGROUND

The association between paediatric traumatic brain injury (pTBI) and post-traumatic attention-deficit/hyperactivity disorder (ADHD) medication usage remains understudied subject.

OBJECTIVE

We aimed to evaluate the association between pTBI and subsequent ADHD medication.

METHODS

A nationwide retrospective cohort study in Finland from 1998 to 2018 included 66 594 patients with pTBI and 61 412 references with distal extremity fractures. ADHD medication data were obtained from the Finnish Social Insurance Institution. The primary outcome was post-traumatic pediatric ADHD medication. A 1-year washout period was applied, and follow-up started 1 year post-pTBI.

FINDINGS

Kaplan-Meier analyses showed higher ADHD medication usage in patients with pTBI, especially post-operatively. Both sex groups exhibited elevated rates compared with the reference group. Over 10 years, cumulative incidence rates were 3.89% (pTBI) vs 1.90% (reference). HR for pTBI was 1.89 (95% CI 1.70 to 2.10) after 4 years and 6.31 (95% CI 2.80 to 14.20) for the operative group after the initial follow-up year. After 10 years, cumulative incidence in females increased to 2.14% (pTBI) vs 1.07% (reference), and in males, to 5.02% (pTBI) vs 2.35% (reference). HR for pTBI was 2.01 (95% CI 1.72 to 2.35) in females and 2.23 (95% CI 2.04 to 2.45) in males over 1-20 years.

CONCLUSIONS

A substantial association between pTBI and post-traumatic ADHD medication was evidenced over a 20-year follow-up period.

CLINICAL IMPLICATIONS

These results stress the need for preventive measures for pTBI and highlight the potential impact of long-term post-traumatic monitoring and psychoeducation.

Nicotine and the developing brain: Insights from preclinical models

Use of tobacco products during pregnancy is associated with increased risk for neurodevelopmental disorders in the offspring. Preclinical models of developmental nicotine exposure have offered valuable insights into the neurobiology of nicotine's effects on the developing brain and demonstrated lasting effects of developmental nicotine exposure on brain structure, neurotransmitter signaling and behavior. These models have facilitated discovery of novel compounds as candidate treatments for attention deficit hyperactivity disorder, a neurodevelopmental disorder associated with prenatal nicotine exposure. Using these models the significance of heritability of behavioral phenotypes from the nicotine-exposed pregnant female or adult male to multiple generations of descendants has been demonstrated. Finally, research using the preclinical models has demonstrated synergistic interactions between developmental nicotine exposure and repetitive mild traumatic brain injury that contribute to "worse" outcomes from the injury in individuals with attention deficit hyperactivity disorder associated with developmental nicotine exposure.

Repetitive Mild Traumatic Brain Injury in an Awake, Unanesthetized Mouse Model of Perinatal Nicotine Exposure Produces Transient Novelty-Seeking and Depression-Like Behaviors

Attention deficit hyperactivity disorder (ADHD) can be a risk factor for repetitive mild traumatic brain injury (mTBI) or concussions such as those that can occur in contact sports. Individuals with ADHD also appear to have a higher risk of poor neurocognitive outcomes after repetitive mTBI. Findings from clinical studies examining the interactions between ADHD and repetitive mTBI vary, likely because of variabilities in experimental design and outcome measures. We used a mouse model of perinatal nicotine exposure (PNE), which displays behavioral, neuroanatomical, and neurotransmitter features consistent with ADHD and subjected the mice to repetitive mTBI. We used a closed head model of mTBI in awake, unanesthetized mice to mimic concussions in humans. The mTBI was repeated three times daily for seven days. The mice in the PNE-mTBI group took longer to regain consciousness after the mTBI and showed transient novelty-seeking and depression-like behaviors. Before the repetitive mTBI, the mice in the PNE group showed attention deficit, which persisted after the mTBI. The mice in the control (non-PNE) group showed a transient attention deficit after the repetitive mTBI but not any of the other behavioral changes seen in the PNE-mTBI group. These findings from an unanesthetized mouse model with a pre-existing condition show that ADHD and repetitive mTBI together contribute to transient novelty-seeking and depression-like behavior supporting the notion that untreated ADHD may be a risk factor for poor neurocognitive outcomes after concussions.

Association of Attention-Deficit/Hyperactivity Disorder Diagnoses With Pediatric Traumatic Brain Injury: A Meta-analysis

IMPORTANCE

There are conflicting accounts about the risk for attention-deficit/hyperactivity disorder (ADHD) following traumatic brain injury (TBI), possibly owing to variations between studies in acute TBI severity or when ADHD was assessed postinjury. Analysis of these variations may aid in identifying the risk.

OBJECTIVE

To conduct a meta-analysis of studies assessing ADHD diagnoses in children between ages 4 and 18 years following concussions and mild, moderate, or severe TBI.

DATA SOURCES

PubMed, PsycInfo, and Cochrane Central Register of Controlled Trials (1981-December 19, 2019) were searched including the terms traumatic brain injury, brain injuries, closed head injury, blunt head trauma, concussion, attention deficit disorders, ADHD, and ADD in combination with childhood, adolescence, pediatric, infant, child, young adult, or teen.

STUDY SELECTION

Limited to English-language publications in peer-reviewed journals and patient age (4-18 years). Differences about inclusion were resolved through consensus of 3 authors.

DATA EXTRACTION AND SYNTHESIS

MOOSE guidelines for abstracting and assessing data quality and validity were used. Odds ratios with 95% credible intervals (CrIs) are reported.

MAIN OUTCOMES AND MEASURES

The planned study outcome was rate of ADHD diagnoses.

RESULTS

A total of 12 374 unique patients with TBI of all severity levels and 43 491 unique controls were included in the 24 studies in this review (predominantly male: TBI, 61.8%; noninjury control, 60.9%; other injury control, 66.1%). The rate of pre-TBI ADHD diagnoses was 16.0% (95% CrI, 11.3%-21.7%), which was significantly greater than the 10.8% (95% CrI, 10.2%-11.4%) incidence of ADHD in the general pediatric population. Compared with children without injuries, the odds for ADHD were not significantly increased following concussion (≤1 year: OR, 0.32; 95% CrI, 0.05-1.13), mild TBI (≤1 year: OR, 0.56; 0.16-1.43; >1 year: OR, 1.07; 95% CrI, 0.35-2.48), and moderate TBI (≤1 year: OR, 1.28; 95% CrI, 0.35-3.34; >1 year: OR, 3.67; 95% CrI, 0.83-10.56). The odds for ADHD also were not significantly increased compared with children with other injuries following mild TBI (≤1 year: OR, 1.07; 95% CrI, 0.33-2.47; >1 year: OR, 1.18; 95% CrI, 0.32-3.12) and moderate TBI (≤1 year: OR, 2.34; 95% CrI, 0.78-5.47; >1 year: OR, 3.78; 95% CrI, 0.93-10.33). In contrast, the odds for ADHD following severe TBI were increased at both time points following TBI compared with children with other injuries (≤1 year: OR, 4.81; 95% CrI, 1.66-11.03; >1 year: OR, 6.70; 95% CrI, 2.02-16.82) and noninjured controls (≤1 year: OR, 2.62; 95% CrI, 0.76-6.64; >1 year: OR, 6.25; 95% CrI, 2.06-15.06), as well as those with mild TBI (≤1 year OR, 5.69; 1.46-15.67: >1 year OR, 6.65; 2.14-16.44). Of 5920 children with severe TBI, 35.5% (95% CrI, 20.6%-53.2%) had ADHD more than 1 year postinjury.

CONCLUSIONS AND RELEVANCE

This study noted a significant association between TBI severity and ADHD diagnosis. In children with severe but not mild and moderate TBI, there was an association with an increase in risk for ADHD. The high rate of preinjury ADHD in children with TBI suggests that clinicians should carefully review functioning before a TBI before initiating treatment.

Inflammation, Anxiety, and Stress in Attention-Deficit/Hyperactivity Disorder

Attention-deficit/hyperactivity disorder (ADHD) is a prevalent and serious neurodevelopmental disorder characterized by symptoms of inattention and/or hyperactivity/impulsivity. Chronic and childhood stress is involved in ADHD development, and ADHD is highly comorbid with anxiety. Similarly, inflammatory diseases and a pro-inflammatory state have been associated with ADHD. However, while several works have studied the relationship between peripheral inflammation and stress in affective disorders such as depression or bipolar disorder, fewer have explored this association in ADHD. In this narrative review we synthetize evidence showing an interplay between stress, anxiety, and immune dysregulation in ADHD, and we discuss the implications of a potential disrupted neuroendocrine stress response in ADHD. Moreover, we highlight confounding factors and limitations of existing studies on this topic and critically debate multidirectional hypotheses that either suggest inflammation, stress, or anxiety as a cause in ADHD pathophysiology or inflammation as a consequence of this disease. Untangling these relationships will have diagnostic, therapeutic and prognostic implications for ADHD patients.

Risk of mild head injury in preschool children: relationship to attention deficit hyperactivity disorder symptoms

AIM

To investigate whether there is an association between mild head injury (MHI) and attention deficit hyperactivity disorder (ADHD) symptoms in preschool children.

METHODS

The study included a patient group of 30 children aged 3-6 years with mild head trauma and a control group of 30 healthy and age- and sex-matched children. The symptoms of ADHD were evaluated using the Conners' Parent Rating Scale-Revised Long (CPRS-RL) form.

RESULTS

The mean age was 4.73 ± 1.13 years in the patient group and 4.65 ± 0.99 years in the control group. No significant differences were determined between the groups in terms of age, gender, parents' age and education (p > 0.05). The total subscale points as reported by the parents of the children with MHI were significantly higher than those for the control group in terms of the following subscales: oppositional, cognitive problems/inattention, hyperactivity, social problems, ADHD index, Conners' Global Index (CGI)-Irritability-Impulsiveness, CGI-Emotional Lability, CGI-Total and DSM-IV ADHD symptoms (p < 0.05). A history of previous trauma treated in emergency services was determined in eight of the 30 patients (26.7%).

CONCLUSIONS

The findings of this study suggest that preschool children with MHI have more pre-injury ADHD symptoms and oppositional and emotional-behavioural symptoms than healthy children without trauma. Clinicians should screen children with MHI for ADHD symptoms and refer them for treatment when necessary. Evaluation of children presenting with MHI by a child psychiatrist may prevent repetition of injuries.

Parent-Reported Mild Head Injury History in Children: Long-Term Effects on Attention-Deficit Hyperactivity Disorder

Objective. Consequences of mild head injury for behavioral adjustment have not been well researched, and little is known about the long-term effects of mild head injury for attention-deficit hyperactivity disorder (ADHD). Methods. In this longitudinal study of 418 children in Jintan City, China, parents reported children's history of head injury at age 6 years, and the Child Behavior Checklist was used to measure child iDSM-IV-oriented ADHD at ages 6 (Wave I) and 12 years (Wave II). Regression models were used to calculate the long-term (Wave II) effect of mild head injury on diagnosed ADHD, while controlling for diagnosed ADHD in Wave I. Results. Fifty-seven children (13.6%) had a single injury and 42 (10.0%) had multiple injuries before the age of 6 years. The long-term effect of multiple mild injury on ADHD at age 12 years was significant (R2 = 0.103, P < .05), even after controlling for ADHD at age 6 years. Conclusions. Multiple, but not single, mild head injuries before the age of 6 years had a significant long-term effect on ADHD. Thus, injuries traditionally overlooked and underreported still pose significant risks to children's long-term behavioral development.

Psychiatric Sequelae of Concussions

PURPOSE OF REVIEW

The purpose of this study was to review the frequency, risk factors, phenomenology, and course of prolonged recovery from concussion and of psychiatric sequelae in pediatric populations.

RECENT FINDINGS

Youth with prolonged recovery from concussions have higher initial symptoms, a history of multiple and/or recent concussions, and a tendency to somatization. Depression, post-traumatic stress disorder, behavioral disorders, and perhaps, suicidal behavior disorder are more common as both short- and longer-term sequelae of concussions. The weight of evidence supports a graduated return to function as compared to prolonged rest, which may actually impede recovery. For those with prolonged recovery, cognitive behavior therapy aimed at education about concussions, improving coping, problem-solving, sleep hygiene, and dealing with anxiety and depression provided in a collaborative care model is superior to usual care. Concussed youth have an increased risk of psychiatric symptoms and sleep disturbance that can be prevented or treated with proper management.