ADHD treatment options: A 2020 scientific analysis of medication versus natural options
This is the first meta-analysis which collated the most prominent behavioural and cognitive interventions for ADHD and examined their effect on cognitive symptomatology. They sought to investigate the effect of non-pharmacological treatments on objective neuropsychological outcomes. They focused entirely on cognitive symptomology using a range of participant populations (children, adolescents, and adults) and included both those who were taking and not taking medications. They were particularly interested in whether the separate functions were differentially affected by interventions and which cognitive function was most amenable to change.
Notably, there was only a slight increased improvement when medication was combined with a non-pharmacological intervention. Studies that included only non-medicated participants still produced a homogeneous moderate to large effect size. This finding highlights the added benefit of a combined medication and non-pharmacological intervention regime but also suggests the possibility of demonstrating improvement in cognitive function with a non-pharmacological intervention alone.
In a surprising outcome, of the interventions studied, physical exercise, regardless of type, was found to be the most effective in targeting and reducing cognitive symptoms of ADHD. All interventions however showed moderate to large effect sizes, indicating their success in reducing cognitive symptoms, as compared to control or less effective interventions. These other interventions included CBT, neurofeedback and cognitive training.
When all the interventions were considered, inhibition and flexibility were the cognitive functions most affected. They demonstrated the ability to undergo a significant change following the interventions and thus could be considered the most malleable. Attention and working memory were both found to have moderate effect sizes.
The present analysis found physical exercise to be the most effective intervention for improving the examined cognitive functions. Periods of intense aerobic exercise have been shown to improve executive functions due to neurotransmitter modifications which relate to central executive tasks. Changes in blood flow to the prefrontal cortex and prioritized resource allocation, which favors executive functions, have been found to occur during physical exercise. Thus, in ADHD patients, where the impairment is argued to be largely executive, physical exercise may be especially beneficial for improving executive functions. Improvements in these cognitive functioning might decrease ADHD-related impairments of attentional and strategic flexibility, inhibition, planning, and working memory.
The present study demonstrated that behavioural interventions can be successful in improving cognitive symptomatology of ADHD. These findings highlight the importance for diagnosing physicians in the field of ADHD to become familiar with the range of alternative treatments available for the neuropsychological symptoms of the disorder. It would be important to include neuropsychological testing in the diagnostic process in order to identify key cognitive deficits, and, in line with the personalized medicine approach, the alternative treatment should be chosen based on the intervention shown to improve the specific deficits. According to this study, although all behavioral interventions designed to aid ADHD seem to have a positive effect on cognitive symptomology, physical exercise, especially aerobic exercise that included targeting executive functions, appears to be the most effective. Based on these findings, it could prove fruitful to integrate complex sports, such as ball sports, martial arts, and physical exercise that involve flexibility and inhibition of impulsive behaviors into ADHD treatment regimen.
Lambez, B., Harwood-Gross, A., Golumbic, E. Z., & Rassovsky, Y. (2020). Non-pharmacological interventions for cognitive difficulties in ADHD: A systematic review and meta-analysis. Journal of Psychiatric Research, 120, 40-55. doi:http://dx.doi.org/10.1016/j.jpsychires.2019.10.007