This study looked at the increased expression of the serotonin transporter protein (SERT) in psoriatic skin compared to patients’ skin without psoriatic lesions and against healthy controls. The severity of psoriasis was also measured in this study and the skin biopsies were immunohistochemically analysed using an antibody to the neurotransmitter’s transporter protein. Commonly used assessments for depression and stress were also employed: Beck’s Depression Inventory (BDI) and salivary cortisol tests.
Serotonin and Psoriasis
Results of these tests found that the severity of psoriasis was positively correlated (0.53) with the number of SERT-positive dendritic cells in the psoriatic skin, implying a relationship between serotonin and psoriasis severity. A negative correlation (0.46) was noted between these cells and salivary cortisol levels, suggesting that chronic stress and SERT expression are connected.
The authors concluded that lowering stress levels and/or treating patients with drugs that modulate serotonin transporter protein levels could help reduce inflammation and lessen psoriasis severity in addition, presumably, to helping patients feel more positive about coping with the skin condition.
Autoimmune Skin Disease and Depression
This correlation of psoriasis and depression was supported by another study carried out by Ghajarzadeh, et al (2012), using the BDI and the Dermatological Quality of Life questionnaire for patients with psoriasis, alopecia areata and vitiligo (all autoimmune skin diseases).
They found that psoriasis was much more likely to negatively affect quality of life related to the skin disorder and that patients in all three groups had significantly higher levels of depression than controls.
Dermatologists as Psychiatrists – Do They Know What They’re Doing?
Rather worryingly, dermatologists are increasingly expected to diagnose and treat psychocutaneous disorders but, according to a survey done by Gee, et al (2013), only a small number are confident in treating such conditions and even fewer have the confidence to prescribe medications for these psychodermatological diseases.
The survey asked 59 practicing dermatologists about their experience in recognising and treating skin conditions with a psychological origin or component in order to determine the gaps in psychodermatologic knowledge and patient care.
Antipsychotics… Prescribed by Your Dermatologist
More than half of the dermatologists reported feeling comfortable making the diagnosis for 8 of 10 psychocutaneous disorders and 57% of the dermatologists felt comfortable diagnosing depression in patients. However, only 11% said they felt confident starting patients on antidepressants and just 3% were comfortable prescribing antipsychotics to patients.
A much higher number of dermatologists (66%) were happy prescribing neuropathic medications but some 21% of dermatologists said they never prescribed these pain medications for their patients. 72% and 68% of the dermatologists reported never prescribing antidepressants or antipsychotics.
Holistic Psychocutaneous Disorder Management
Confidence in their ability to successfully manage patients’ skin disorders related to mental health was also low for most conditions. Just 24% had confidence managing patients’ depression, 27% for delusions of parasitosis, 38% for compulsive skin-picking (such as in dermatitis artifacta) and only 15% of dermatologists reported confidence treating a patient with body dysmorphic disorder, an increasingly recognised condition.
These kinds of figures demonstrate a significant gap between responsibility, knowledge and training for dermatologists and suggest that extra support, a more holistic approach to managing skin disease and further research into psychocutaneous disorders is necessary to improve patient care.