Abstract
It is clear that illicit drugs can contribute to psychiatric disorders. In this issue of the Journal, the extent of, and associations with, stimulant and cannabis use are covered in two Australian studies using data from the 2007 National Survey of Mental Health and Wellbeing – a survey which is providing us with valuable data. Both stimulant use and cannabis use disorders carry with them high rates of comorbidity (Sara et al., 2012; Teesson et al., 2012), with up to two-thirds of those with cannabis use disorder having a co-morbid condition. The use of stimulants and cannabis is found to be high among young men (a group that do not seek help), with stimulant use seeming to be a problem for young, non-heterosexual men. Of great concern is that those with stimulant use disorder are twice as likely to have a family history of schizophrenia or bipolar disorder compared to those without the disorder; the concern here is that stimulant use can precipitate psychosis in vulnerable individuals.
The precise mechanism by which illicit substances can induce psychosis remains elusive, as shown in the review of recent human studies and animal models by Gururajan and colleagues (2012). This review demonstrates the importance of developing good animal models to examine neurobiological mechanisms. The take away message is the complexity of the relationship between genes, developmental stage of exposure and gender influences in contributing to psychosis. These issues are taken up further in a commentary by Sara (2012), who also raises issues about drug laws.
The technical advances of neuro-imaging are demonstrated in an elegant study by Looi et al. (2012), who used structural imaging to demonstrate differential putaminal morphology between patients with Huntington’s disease, frontotemporal dementia and Alzheimer’s disease. These imaging findings may prove to be useful in helping us to distinguish the different types of dementia.
Treating patients with severe and enduring anorexia nervosa is daunting and the possibility of new approaches to their management is something we all hope for. Regrettably, the review by Hay et al. (2012) does not provide us with a magic bullet. New approaches are reviewed and unsurprisingly there are no randomised controlled trials to inform us. There is some promise in modified forms of cognitive behavioural therapy and developments of cognitive and emotion skill retraining but clearly more work needs to be done. What is clear is that the goals of treatment need to be reappraised with this group of patients in a similar manner to that used in the clinical staging of schizophrenia.
The treatment of depression involves more than just the removal of depressive symptoms; the restoration of wellbeing is essential, with recovery of positive affect an essential component of this, as pointed out by Nierenberg et al. (2012). They report the development of a new self-report scale, with good psychometric properties, measuring positive affect. This new scale, while correlated with rating of depression, measures a different dimension that we need to be assessing when measuring recovery in our patients; an aspect of remission that is of prime importance to depressed patients. This brings us to sex.
Sexual dysfunction is often the focus of research in mood disorders, especially when this occasionally arises with antidepressant medications, as pointed out by Worsley and Kulkarni (2012), but little attention has been paid to the positive aspects of healthy sexual functioning or neurobiological mechanisms that may lead to improved mood associated with the female orgasm. This has now been addressed in a perspective by Bou Khalil (2012), who proposes that mood may be improved as a result of either vagal stimulation or oxytocin release following orgasm. The beneficial effects of improved interpersonal functioning would, of course, add to these neurobiological influences.