From culture to the brain

Psychiatric disorders evolve in and are moulded by the environment and culture of the individual. This month’s issue opens with a debate about whether excessive Internet gaming should qualify as a mental disorder – indeed challenging our views about what a culture bound syndrome can be. King et al. (this issue) take issue with a paper by Dullur and Starcevic (2018) who believe that Internet gaming should not qualify as a disorder, arguing that the addiction model for gambling is misleading, it does not fit the current model of a mental disorder, it risks pathologising normal gaming and the label does not inform treatment. King counters, noting that no diagnosis in the current system has total consensus, that the condition leads to impaired control and functional impairment in diverse life domains, that it does not necessarily pathologise recreational gambling, that it enhances the search for and access to treatment and that the condition is commonly co-occurring with other common mental disorders. This discussion exemplifies how the Australian & New Zealand Journal of Psychiatry (ANZJP) seeks to reinforce its role as the principal forum for such clinically and policy salient debates.

Following the policy theme, Reppermund et al. (this issue) argue that people with intellectual disability, despite having very high levels of psychiatric comorbidity, are poorly recognised in Australian mental health policy. They argue that, as a consequence, people with intellectual disability face major barriers to access mental health treatments and services – heightened by the nature of the disability and further aggravated by poor inter-sector coordination. They argue for coordinated service provision, policy and legislation to address the complex needs of this population and facilitate implementation through a cross-agency strategy encompassing both the disability and health sectors.

Transcultural issues – a recurring theme in the journal – are again reflected in a meta-analysis of cognitive behavioural therapy for Chinese people. There is uncertainty as to whether this kind of psychotherapy would have efficacy in diverse populations with differing cultural values and beliefs (Xu and Tracey, 2016). Ng et al. (this issue) found medium effect sizes for anxiety, depression, well-being and caregiving stress and small effect sizes for psychotic symptoms and addictive behaviours, concordant with findings in western populations, supporting the universality of cognition as a targetable phenotype and of cognitive behaviour therapy as a keystone transculturally valid intervention.

Mental Health First Aid (MHFA) has been a substantial driver of population level knowledge as well as attitudinal and culture change, but is less well validated in youth. Youth is the onset epoch of mental illness, yet young people have poorer engagement with treatment resources than adults. Hart et al. (this issue) explored the effect of a classroom-based version of MHFA in 15- to 18-year-old students, finding improved first aid intentions (the primary outcome) as well as confidence and reduced stigmatising beliefs. They concluded that teen MHFA is both effective and feasible in adolescents in the short term and merits widespread dissemination to improve adolescent mental health.

Depression has been argued to be a psychomotor disorder (Parker et al., 2017). In this context, Averill et al. (this issue) explored whether activity levels or psychomotor speed predicted treatment response. Using actigraphy, they studied a small and non-blind cohort of inpatients with major depression for 3 weeks and found that early change in both activity levels and psychomotor speed were associated with improvement in depression. Methodological limitations and correlation/causation confounds notwithstanding, this provides some support for the value of actigraphic technology as a theragnostic biomarker, as well as for Parker’s notion.

Prince (2018) has argued that ‘If you can’t measure it, you can’t manage it’ and Page et al. (this issue) extend this to choice of tools to quantify the potential impact of a population-level suicide risk reduction intervention. They argue that traditional static measures of population attributable risk may overstate the potential efficacy of suicide risk reduction interventions creating unrealistic expectations. They argue that dynamic measures of impact at a population level that are based on systems science models incorporating change over time would model more modest, and perhaps more realistic, estimates of benefit. Being better able to measure benefit therefore should result in being more able to manage it, particularly in the domains of providing accurate information to guide decision making and allocate resources to prevent the population burden of suicide.

The Mood Mechanic Course is an Internet-delivered cognitive and behavioural treatment that targets symptoms of both anxiety and depression. Dear et al. (this issue) compared clinician-guided or self-guided treatment, finding baseline to endpoint improvement in many symptom domains in both groups, but no differences between the treatment conditions. The absence of a time- and intensity-matched inert control condition complicates interpretation, as does the sample size, which allowed only moderate effect sizes to be detected. The intervention was associated with high satisfaction ratings and adds to the literature on the culture shift towards Internet-based interventions.

Oxidative stress, a particular interest of mine, is increasingly understood as a key operative pathway across psychiatric disorders (Ng et al., 2008), with glutathione (GSH) functioning as the brain’s principal antioxidant defence system. Oxidative stress and in particular reduced GSH is a replicated finding in schizophrenia. This hypothesis was upheld by Zhang et al. (this issue) who explored total and reduced GSH levels in postmortem brain samples in people with schizophrenia. Why GSH is reduced is, however, not well understood. While they confirmed lower levels of both total and reduced GSH in people with schizophrenia than in controls, they failed to detect any change in either the protein or messenger RNA (mRNA) level of the key regulatory enzymes for the GSH pathway, the glutamyl-cysteine ligase (GCL) catalytic subunit (GCLC) and the GSH peroxidase (GPx)-like protein. They thus seemed to exclude the role of these enzymes from the pathways to oxidative stress in a larger sample size than in previous studies. They conclude that alternate pathways in particular N-methyl-d-aspartate receptor (NMDAR) hypofunction and neuro-inflammation need to be explored.

Finally, this issue concludes with a series of promising reports of deep brain stimulation. Ferrand et al. (this issue) showcase a case series of people receiving deep brain stimulation for severe and treatment-refractory obsessive-compulsive disorder, suggesting efficacy in these highly selected patients. Bosanac et al. (this issue) echo support for this finding, arguing for the need for a national network of experts in the area. Kanodia and Guha (this issue) conclude with a case report of bilateral deep brain stimulation of the globus pallidus internus showing benefit for symptoms of tardive dyskinesia.

In sum, this issue spans culture to neuroscience and debate to consensus, and in doing so once again provides a megaphone for the diversity of Australasian psychiatry.