Journal Article Annotations
2023, 2nd Quarter
Annotations by J. Jewel Shim, MD
July, 2023
The finding:
The authors sought to test the hypothesis that modulating the glutamate system would be effective in treating the core symptoms of body focused repetitive behavior disorders such as trichotillomania and skin picking disorder. Previous work has shown that N-acetylcysteine, another glutamate modulator, has efficacy in treating these disorders. The study results demonstrated that memantine, a glutamate receptor antagonist, was superior to placebo as measured by the NIMH Trichotillomania symptom severity scale, which the investigators also modified to rate the severity of skin picking symptoms. The effect size was 1.76, similar to or superior to that found with behavioral treatment, and the NNT was 1.9. These results suggest that memantine could be a first line treatment for these disorders.
Strength and weaknesses:
One major strength is the randomized, double blind, placebo controlled study design which minimized the risk of bias. Some weaknesses highlighted by the study authors were a lack of psychometric validation of their modified NIMH Trichotillomania Severity Scale and that the symptom severity of the study population was rated to be mild-moderate, thus limiting the ability to clearly state the effectiveness of memantine across all levels of severity. Finally, the investigators pointed out that while efficacy was shown during the 8 week trial, it remains to be seen whether memantine would continue to be effective over the long term.
Relevance:
To date, there are few evidence based treatments for trichotillomania and skin picking disorder; this study spotlights memantine as a promising novel treatment.
The finding:
This study reviewed relevant literature and evidence base for the treatments of 5 primary psychodermatological disorders (PPDs): trichotillomania, skin picking disorder, nail biting, delusional parasitosis, and dermatitis associated with compulsive handwashing. In general, 7 classes of medications were identified as the most common and most efficacious treatments among the controlled trials reviewed. Effective medication classes included selective serotonergic reuptake inhibitors, tricyclic antidepressants, antipsychotics, anticonvulsants, and N-acetylcysteine.
Strength and weaknesses:
This study was a review rather than a meta-analysis, limiting the clear assessment of efficacy of various treatments. Further, the trials reviewed, while controlled, generally had few subjects, and no open label trials were examined. The review only included pharmacologic interventions in these disorders, and did not review non-pharmacological treatments, which have shown benefit in treating these disorders.
Relevance:
This review is helpful in identifying and summarizing the existing controlled research for PPDs and provides a quick reference for treatment options for these disorders.
The finding:
The study authors sought to better characterize the possible association between stress and psoriasis as mediated through the hypothalamic-pituitary-adrenal (HPA) axis. They found that prolonged stress was associated with blunting of the HPA axis, as measured by lowered levels of cortisol, and elevated adrenocorticotrophic hormone levels. HPA axis dysregulation was also correlated with an elevation in proinflammatory cytokines, including interleukin-7, which drives the hyperproliferation of keratinocytes and leads to development of psoriatic lesions.
Strength and weaknesses:
This novel study examined every day stress exposure and how it correlates with specific markers of HPA axis dysregulation, markers of inflammation, and the association of these multiple factors with the expression of psoriatic disease. However, this was a small, cross-sectional study and as such could not establish a cause-effect relationship between stress and worsened psoriatic lesion severity.
Relevance:
In further elucidating the impact of stress on psoriatic disease severity, this study suggests targets for interventional treatment.
This is an interesting paper that takes a novel view of the far-reaching impact of climate change. Via direct and indirect mechanisms, climate change can be shown to mediate the severity and outcomes of atopic dermatitis (AD).
In particular the authors discuss how climate change can promote inflammation , which is a common etiology for a number of skin diseases such as AD. In addition, the authors describe how climate change, which is associated with extreme weather events such as floods, hurricanes, and tornadoes, drought and/or extreme heat, is linked to an increase in mental health disorders by way of their impact on material possessions/shelter, community infrastructure, and access to resources. Moreover, exposure to the more extreme effects of climate change can also have a direct impact on mental health. Disorders such as acute stress/trauma, grief, and mood disorders may result or become exacerbated. Mental disorders and associated stress have been shown to exacerbate AD and other inflammatory skin conditions. The authors also point out that climate change compounds already existing social and financial inequities for vulnerable and marginalized populations.