Does childhood attention-deficit/hyperactivity disorder predict risk-taking and medical illnesses in adulthood?

Mild traumatic brain injury and ADHD: a systematic review of the literature and meta-analysis

OBJECTIVE

This study investigated the association between mild traumatic brain injury (mTBI) and ADHD, which increases risk of injuries and accidents.

METHOD

We conducted a systematic review and meta-analysis of studies that examined the relationship between mTBI and ADHD.

RESULTS

Five studies, comprising 3,023 mTBI patients and 9,716 controls, fit our a priori inclusion and exclusion criteria. A meta-analysis found a significant association between ADHD and mTBI, which was significant when limited to studies that reported on ADHD subsequent to mTBI and when the direction of the association was not specified, but not for studies that reported mTBI subsequent to ADHD. Heterogeneity of effect size and publication biases were not evident.

CONCLUSION

The literature documents a significant association between mTBI and ADHD. Further clarification of the relationship and direction of effect between mTBI and ADHD and treatment implications could have large clinical, scientific, and public health implications.

Effect of diet on brain metabolites and behavior in spontaneously hypertensive rats

Attention-deficit hyperactivity disorder (ADHD) is a heterogeneous psychiatric disorder affecting 5-10% of children. One of the suggested mechanisms underlying the pathophysiology of ADHD is insufficient energy supply to neurons. Here, we investigated the role of omega 3 fatty acids in altering neural energy metabolism and behavior of spontaneously hypertensive rats (SHR), which is an animal model of ADHD. To this end, we employed Proton Magnetic Resonance Spectroscopy ((1)H MRS) to evaluate changes in brain neurochemistry in the SHR following consumption of one of three experimental diets (starting PND 21): fish oil enriched (FOE), regular (RD) and animal fat enriched (AFE) diet. Behavioral tests were performed to evaluate differences in locomotor activity and risk-taking behavior (starting PND 44). Comparison of frontal lobe metabolites showed that increased amounts of omega 3 fatty acids decreased total Creatine levels (tCr), but did not change Glutamate (Glu), total N-Acetylaspartate (tNAA), Lactate (Lac), Choline (Cho) or Inositol (Ino) levels. Although behavior was not significantly affected by different diets, significant correlations were observed between brain metabolites and behavior in the open field and elevated plus maze. SHR with higher levels of brain tCr and Glu exhibited greater hyperactivity in a familiar environment. On the other hand, risk-taking exploration of the elevated plus maze's open arms correlated negatively with forebrain tNAA and Lac levels. These findings support the possible alteration in energy metabolites in ADHD, correlating with hyperactivity in the animal model. The data also suggest that omega 3 fatty acids alter brain energy and phospholipid metabolism.

The relationship between ADHD symptomatology and self-harm, suicidal ideation, and suicidal behaviours in adults: a pilot study

The aim of this study was to explore whether individuals with attention-deficit/hyperactivity disorder (ADHD) are at risk of harm over the lifespan due to increased rates of self-harm, suicidal ideation and suicidal behaviour, and whether this association is mediated by psychosocial factors. Sixty-six adults (43 men, 23 women; 18-65 years) participated in this study involving clinical interview and retrospective self-report measures of ADHD symptoms, self-harm/suicidal behaviour, mental health disorders, and coping style measures. Significant associations were found between ADHD symptom severity and self-reported histories of self-harm behaviour, suicidal ideation, and suicide attempts (all p values<.05). These relationships between self-destructive behaviours and ADHD symptom severity were found to be significantly and differentially mediated by psychosocial variables (all p values<.05) including comorbidity (mood, anxiety, drug, and alcohol abuse disorders) and emotion-focussed coping style. This study suggests that linkages between self-injurious behaviour and ADHD symptomatology may be due primarily to comorbid mental health disorders and emotion-focussed coping. The identification of these mediating factors and processes may potential pathways for intervention in reducing suicide and self-harm risk amongst those with ADHD symptoms.