Increased use of mental health services related to isotretinoin treatment: a 5-year analysis

Prescribing Patterns of Isotretinoin for Acne Among Dermatologists in Central Jordan

INTRODUCTION

Prescribing practices among dermatologists play a crucial role in managing acne, particularly concerning medications like isotretinoin. In Jordan's central region, encompassing the Governorates of Amman, Balqa, Zarqa, and Madaba, dermatologists in both public and private sectors encounter diverse cases of acne. Understanding their prescription patterns and awareness regarding isotretinoin usage is essential for optimizing acne treatment outcomes and minimizing potential risks.

METHODS

This study aimed to evaluate dermatologists' practices in prescribing isotretinoin for acne. It relied on the descriptive analytical approach, with the study population including all dermatologists working in the public and private sectors in the central region of Jordan. Simple random sampling was used to include 147 male and female doctors. An online questionnaire was adopted to collect data from the study sample, which was distributed through social media platforms and messaging platforms such as Facebook, WhatsApp, and Instagram to dermatologists working in the central region.

RESULTS

 In this study of 147 dermatologists, 58 (39.45%) prescribed isotretinoin primarily for severe acne, and 53 (36.06%) prescribed isotretinoin to about 50-100 patients per year, with the initial dosage based on guidelines (n=102, 69.39%). The majority (n=115; 78.23%) refrained from prescribing if liver enzymes were elevated. Pregnancy tests were required by 42 (28.57%) in the first session, while 78 (53.07%) deemed it the patient's responsibility. Common precautions included sunscreen (n=77; 52.38%) and moisturizing cream (n=31, 21.09%). Only six of the dermatologists (4.08%) advised their patients not to use contact lenses, and only 17 (11.57%) prescribed moisturizing eye drops.

CONCLUSION

This study's findings emphasize how crucial physicians' experience is when it comes to prescribing isotretinoin for severe acne. Continued educational initiatives are imperative to address gaps in patient information and safeguards in order to optimize treatment outcomes and ensure patient safety.

Practice and attitude of general practitioners towards initiating isotretinoin for acne vulgaris in Fars province, Iran: cross-sectional study

BACKGROUND

Since general practitioners manage acne-related referrals, there needs to be more information in Iran about how drugs such as Isotretinoin are prescribed and the treatment plan. Thus, this study aimed to evaluate general practitioners s' practices and attitudes in prescribing Isotretinoin for acne vulgaris in primary care.

METHODS

This web-based cross-sectional descriptive study was conducted using two questionnaires designed with the target population of GPs working in Fars province in 2021 regarding the prescription of Isotretinoin. Moreover, demographic information, questions about interest in dermatology, and participation in dermatology workshops were gathered.

RESULTS

A total of 308 complete questionnaires were obtained. According to our results, 85 (27.6%) GPs prescribed Isotretinoin in primary care. Based on our results, higher age (OR: 1.042; CI95%: 1.013-1.072; P-value:0.004) and attending dermatological courses (OR: 3.280; CI95%: 1.592-6.755; P-value:0.001) were significantly correlated with more frequent Isotretinoin administration. Among GPs who do not prescribe Isotretinoin, the most common causes are concerns about liver dysfunction (54.7%), teratogenic concerns (37.2%), and lack of familiarity with the drug (31.4%) respectively.

CONCLUSION

The results of this study depicted the reluctance of most physicians to prescribe Isotretinoin and factors such as taking part in supplementary courses under the supervision of dermatologists and following national guidelines that could encourage them to prescribe Isotretinoin.

Factors associated with increased suicidality risk following referral for isotretinoin commencement

OBJECTIVE

To establish whether there is a significant change in suicidality risk following psychiatric assessment for commencement of isotretinoin and identify factors that underpin any potential risk change.

METHOD

Retrospective cohort study. Suicidality risk was defined as a combination of the following: (i) actual/intended self-harm and/or attempted/completed suicide, and (ii) increased service utilisation associated with suicidal ideation/behaviour. All patients referred to Psychiatry for assessment prior to commencement of isotretinoin between 2014 and 2019 were examined. Inclusion criteria: >16 years of age, assessed for commencement of isotretinoin, complete clinical records. Data were collected by reviewing the Electronic Patient Records. Fifty-seven patients were eligible. We employed descriptive statistics, parametric/non-parametric/normality tests and logistic regression analysis, using socio-demographic and clinical characteristics as independent parameters, and suicidality risk as the dependent parameter.

RESULTS

Actual/intended self-harm/attempted suicide decreased significantly following assessment without significant change in service utilisation. Female gender, absence of protective factors and assessment by Consultation-Liaison Psychiatry were linked to increased suicidality risk, after controlling for age, ethnicity, recommendation for isotretinoin, and substance misuse.

CONCLUSIONS

Psychiatric assessment is helpful before commencing isotretinoin. Female gender, and absence of ongoing psychopharmacological and/or psychological intervention and/or regular psychiatric follow-up predict increased suicidality risk among patients assessed for prescription of isotretinoin.

Isotretinoin and neuropsychiatric side effects: Continued vigilance is needed

Background

Isotretinoin (13-cis-retinoic acid, marketed under the names Accutane, Roaccutane, and others) is an effective treatment for acne that has been on the market for over 30 years, although reports of neuropsychiatric side effects continue to be reported. Isotretinoin is an isomer of the active form of Vitamin A, 13-trans-retinoic acid, which has known psychiatric side effects when given in excessive doses, and is part of the family of compounds called retinoids, which have multiple functions in the central nervous system.

Methods

The literature was reviewed in pubmed and psychinfo for research related to isotretinoin and neuropsychiatric side effects including depression, suicidal thoughts, suicide, mania, anxiety, impulsivity, emotional lability, violence, aggression, and psychosis.

Results

Multiple case series have shown that successful treatment of acne with isotretinoin results in improvements in measures of quality of life and self esteem However, studies show individual cases of clinically significant depression and other neuropsychiatric events that, although not common, are persistent in the literature. Since the original cases of depression were reported to the United States Food and Drug Administration, numerous cases have been reported to regulatory agencies in the United Kingdom, France, Ireland, Denmark, Australia, Canada, and other countries, making isotretinoin one of the top five medications in the world associated with depression and other neuropsychiatric side effects. Clinicians are advised to warn patients of the risks of neuropsychiatric side effects with isotretinoin which may arise from the medication itself, and not just as a side effect of acne or youth.

Association of brain-derived neurotrophic factor levels and depressive symptoms in young adults with acne vulgaris

BACKGROUND

Brain-derived neurotrophic factor (BDNF) is one of the proteins that contributes to the survival, growth, maintenance of neurons, and plays important roles in the pathophysiology of depression. It has been reported that depression is closely associated with the pathogenesis of acne vulgaris disease. But, there is no report of serum BDNF levels in patients with acne vulgaris. The study aimed to determine the potential association between BDNF and depressive symptoms in young adults with acne vulgaris.

METHODS

In this analytical cross-sectional study, the serum BDNF levels were measured in peripheral blood samples of 20 consecutive acne vulgaris patients with depression and 98 consecutive acne vulgaris patients without depression and also compared it with a 59 healthy control group by using a ELISA. The potential correlation between the BDNF levels, interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-α), and depressive symptoms such as nine-item patient health questionnaire (PHQ-9) and Athens insomnia scale (AIS) were evaluated with multivariate logistic regression analysis.

RESULTS

Our results showed that levels of BDNF expression were lower in consecutive acne vulgaris patients when compared with healthy control (P < 0.05). There was a negative correlation between levels of BDNF and the PHQ-9 scores (r = - 0.486, P < 0.001). Furthermore, acne vulgaris patients with depression showed lower serum BDNF levels (10.96 ± 2.12 ng/ml) compared with acne vulgaris patients without depression (13.85 ± 2.47 ng/ml), as well as with healthy control (14.35 ± 2.70 ng/mg; both P < 0.05). No difference was found in serum BDNF levels between healthy control and acne vulgaris patients without depressive symptoms (z = 0.964, P > 0.05). Similarly, the overall area under the curve of receiver operating characteristic was 0.82, indicating the highly conserving of serum BDNF levels as an biomarker for screening of depression in young adults with acne vulgaris (72% sensitivity and 85% specificity).

CONCLUSION

Serum BDNF levels were decreased and negatively associated with depressive symptoms in young Chinese adults with acne vulgaris.

Comparison of Quality of Life, Depression, Anxiety, Suicide, Social Anxiety and Obsessive-Compulsive Symptoms Between Adolescents with Acne Receiving Isotretinoin and Antibiotics: A Prospective, Non-randomised, Open-Label Study

BACKGROUND

The effects of isotretinoin on suicide, social anxiety and obsessive-compulsive symptoms in adolescents with acne have not been sufficiently investigated.

OBJECTIVE

This study aimed to evaluate the quality of life, depression, anxiety, suicide, social anxiety, and obsessive-compulsive symptoms of adolescents receiving systemic isotretinoin and antibiotic treatments at baseline and at 3 months.

METHODS

The study included a total of 102 adolescents using isotretinoin (n = 60) and antibiotics (n = 42). The Acne Quality of Life Scale (AQLS), Hospital Anxiety and Depression Scale (HADS), Suicide Probability Scale (SPS), Liebowitz Social Anxiety Scale (LSAS), and Maudsley Obsessive-Compulsive Question List (MOCQL) were administered to both groups at baseline and at 3 months. In order to exclude patients with comorbid psychiatric disorders, the patients were evaluated at the beginning of the study with the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version (K-SADS-PL).

RESULTS

There were no significant differences in the mean age, gender distribution, educational level, and family history of mental illness between the two groups. There were significant decreases in the Global Acne Grading System scores, visual analogue scale scores, AQLS scores, total and subscale scores of LSAS, and total and subscale scores of MOCQL at 3 months compared with baseline in both groups. However, there were no significant changes in the total and subscale scores of HADS and total and subscale scores of SPS at 3 months compared with baseline in both groups.

CONCLUSION

We found that neither isotretinoin nor antibiotic treatment affected the levels of depression, anxiety, and suicide in acne patients. Moreover, both isotretinoin and antibiotic treatment were shown to improve the quality of life, social anxiety, and obsessive-compulsive symptoms in acne patients. However, clinicians should be careful about psychiatric side effects in patients using isotretinoin. Further studies with a larger number of cases and with a longer follow-up period are needed to investigate the complex effects of isotretinoin on the central nervous system.

Risk of suicide attempt associated with isotretinoin: a nationwide cohort and nested case-time-control study

Background

Isotretinoin is the only effective treatment for severe acne. An isotretinoin-related suicide risk is still debated and under scrutiny by regulatory agencies. Our objectives were: to assess the risk of suicide attempt before, during and after isotretinoin treatment; to detect any potential triggering effect of isotretinoin initiation on suicide attempt.

Methods

We implemented a cohort and nested case-time-control study of subjects treated with oral isotretinoin (course or initiation) aged 10–50 years, using the Nationwide French Health Insurance data (2009–2016). The main outcome was hospitalized suicide attempt. Standardized incidence ratios for hospitalized suicide attempts were calculated before, during and after isotretinoin treatment. The number of isotretinoin initiations was compared in risk and control periods of 2 months using a case-time-control analysis.

Results

In all, 443 814 patients (median age 20.0 years; interquartile range 17.0–27.0 years) were exposed to isotretinoin, amounting to 244 154 person-years, with a marked seasonality for treatment initiation. Compared with the French general population, the occurrence of suicide attempts under isotretinoin treatment was markedly lower, with a standardized incidence ratio of 0.6 [95% confidence interval (CI) = 0.53–0.67]; the same applied, to a lesser extent, before and after isotretinoin treatment. In the case-time-control analysis, among cases of suicide attempt, 108 and 127 isotretinoin initiations were observed in the risk and control periods respectively (i.e. 0–2 months and 2–4 months before the date of suicide attempt). The comparison with the 1199 and 1253 initiations observed among matched controls in the same two periods yielded a case-time-control odds ratio of 0.89 (95% CI = 0.68–1.16). A sensitivity analysis using three-month periods and a complementary analysis adding completed suicides for case definition showed consistent results.

Conclusion

Compared with the general population, a lower risk of suicide attempt was observed among patients exposed to isotretinoin and there was no evidence for a triggering effect of isotretinoin initiation on suicide attempt. A selection of patients at lower risk for suicidal behaviour and appropriate treatment management could explain these findings. Risk management plans should therefore be maintained.

Psychiatric and Developmental Effects of Isotretinoin (Retinoid) Treatment for Acne Vulgaris

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Isotretinoin teratogenicity well established; psychiatric effects documented, controversial

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Disturbed retinoid signaling implicated in isotretinoin teratogenic and psychiatric effects

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Effect of genetics on susceptibility to psychiatric side effects is possible, not yet known

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Postnatal neurocognitive effects of isotretinoin not yet established

Background

An association between isotretinoin (13-cis-retinoic acid, sold under trade names including Accutane [Hoffmann-La Roche Inc, Basel, Switzerland]) and birth defects, depression, and suicide is well documented but controversial. A link to psychosis and exacerbation of bipolar symptoms is less extensively addressed in the literature.

Objective

Given recent conceptualization of psychotic disorders as neurodevelopmental, and current interest in possible shared etiology of different neurodevelopmental disorders such as psychosis, autism, and intellectual disability, this review concurrently examines the literature on developmental (primarily teratogenic) and psychiatric side effects of isotretinoin exposure. The goal of concurrent review is to identify shared mechanisms in the literature that may inform future efforts to clarify the neurocognitive and psychiatric effects of isotretinoin exposure at different developmental stages or given different genetic backgrounds.

Methods

Literature was obtained by PubMed search for the term isotretinoin in combination with each of the terms psychosis, psychiatric, and teratogenic. Resulting articles met inclusion criteria for review if they addressed psychiatric side effects of isotretinoin treatment or the neurobehavioral teratology of isotretinoin.

Results

The association of isotretinoin exposure with prenatal developmental toxicity is well established. Although numerous reports also link isotretinoin treatment with psychiatric side effects, this association remains controversial.

Conclusions

The extent to which isotretinoin influences pediatric and adult development and cognition, and whether and why certain individuals may be susceptible to psychiatric side effects, remains to be clarified. Curr Ther Res Clin Exp. 2019; 80:XXX–XXX)

Psoriasis and suicidality: A review of the literature

Psoriasis is a chronic systemic inflammatory skin disease, which has been associated with an increased risk of numerous medical and psychiatric comorbidities, including suicidality. Suicidality, which can be divided into the categories of suicidal ideation, suicide attempt, and completed suicide, is highly prevalent in the psoriasis population, and multiple studies have been published on the subject of psoriasis and suicidal ideation and behavior (SIB), including two recent meta-analyses. However, the available literature is limited and inconsistent, and the association between the two remains incompletely understood. The present review aims to cohesively synthesize and summarize the available evidence, while making a clinically relevant distinction between the sub-categories of suicidality, by examining not only the epidemiology of the association but also the plausible molecular mechanisms and the potential influence of biologic therapies. Additionally, this review aims to critically examine and understand the potential contribution of depression in the psoriasis and suicidality relationship. This will allow us to better understand the complex and multi-faceted relationship between psoriasis and suicidality, to identify those who may be most at risk for SIB, to make evidence-based clinical decisions regarding treatment and management, and to more completely address the needs of psoriasis patients.

Association of Isotretinoin With Depression and Suicide: A Review of Current Literature

Acne vulgaris, a condition that can affect people at any age, is the most common cause of referral to a dermatologist. Isotretinoin (ITT) is the most effective treatment available, but serious adverse effects, including a possible association with depression and suicide, limit its use. We review the current literature regarding the association of ITT with depression and suicide. Case reports and database studies show a clear association, and this association is biologically plausible. Although prospective studies have opposite results, limitations make them unsuitable to identify a subgroup of patients who may be at risk of developing depression or suicidal ideation with ITT. Overall, it seems some people might be at risk, particularly those with a personal or family history of mental disorder, but further studies are needed to identify those patients who would benefit from an early referral to a mental health professional when ITT is initiated. Currently, no conclusions can be drawn, and it seems appropriate to regularly screen all patients on ITT for depressive symptoms and suicidal ideation and promptly refer them to a mental health professional if any are found.

Psychiatric disorders, acne and systemic retinoids: comparison of risks

BACKGROUND

The link between isotretinoin, treatment of a severe form of acne, and psychiatric disorders remains controversial, as acne itself could explain the occurrence of psychiatric disorders. This study aims at assessing the disproportionality of psychiatric adverse events reported with isotretinoin in the French National PharmacoVigilance Database, compared with other systemic acne treatments and systemic retinoids.

MATERIALS AND METHODS

Data were extracted from the French National PharmacoVigilance Database for systemic acne treatments, systemic retinoids and drugs used as comparators. Each report was subjected to double-blind analysis by two psychiatric experts. A disproportionality analysis was performed, calculating the number of psychiatric ADRs divided by the total number of notifications for each drug of interest.

RESULTS

Concerning acne systemic treatments: all 71 reports of severe psychiatric disorders involved isotretinoin, the highest proportion of mild/moderate psychiatric adverse events was reported with isotretinoin (14.1%). Among systemic retinoids, the highest proportion of severe and mild/moderate psychiatric events occurred with isotretinoin and alitretinoin.

CONCLUSION

Our study raises the hypothesis that psychiatric disorders associated with isotretinoin are related to a class effect of retinoids, as a signal emerges for alitretinoin. Complementary studies are necessary to estimate the risk and further determine at-risk populations.

Affective disorders as potential complication of anti-acne treatment with isotretinoin: A case series

OBJECTIVE

To analyse cases of 9 patients (18-27 yo) who were consequently admitted to our department and treated with affective disorders (AD) while undergoing isotretinoin (INN) therapy.

METHODS

A semi-structured questionnaire designed by the authors was used to analyse many variables related to demographic characteristics, dermatologic and psychiatrics symptoms, AD course and treatment, family history of mental disorders, building on medical histories of patients and their families, and available medical records.

RESULTS

Patients were diagnosed (DSM-IV-TR) with: a major depressive episode (4 patients), a recurrent major depressive episode (3), a bipolar mixed episode (1), and rapid cycling bipolar I disorder (1). The mean time from the first use of INN to: I. the onset of mental disorders was approximately 2 months (1-6 months), II. a visit with a psychiatrist was about 12 months (1-38 months). The predictors of occurrence of AD included a family history of AD and a prior episode of mental disorders. The onset of AD was in most cases preceded by prodromal symptoms such as headaches, sleep disorders, fatigue, drowsiness, or general weakness. Five patients reported suicidal ideation, four patients showed suicidal tendencies, and two persons attempted to commit suicide during the treatment.

CONCLUSIONS

Psychiatrists should pay special attention to isotretinoin as a drug that may trigger episodes of AD, particularly in patients with a family history of AD or prior episodes of mental disorders. Isotretinoin therapy of patients with acne and a family history of AD or prior episodes of mental disorders requires special care and, if symptoms of depression develop or worsen during the INN treatment, collaboration between a dermatologist and a psychiatrist is needed.

Retinoic acid and affective disorders: the evidence for an association

OBJECTIVE

Isotretinoin (13-cis-retinoic acid), approved by the US Food and Drug Administration for the treatment of acne, carries a black box warning related to the risk of depression, suicide, and psychosis. Retinoic acid, the active form of vitamin A, regulates gene expression in the brain, and isotretinoin is its 13-cis isomer. Retinoids represent a group of compounds derived from vitamin A that perform a large variety of functions in many systems, in particular the central nervous system, and abnormal retinoid levels can have neurologic effects. Although infrequent, proper recognition and treatment of psychiatric side effects in acne patients is critical given the risk of death and disability. This article reviews the evidence for isotretinoin's relationships with depression and suicidality.

DATA SOURCES

The PsycINFO, MEDLINE, and PubMed searchable database indexes were searched for articles published in the English language from 1960 to June 2010 using the key words isotretinoin, retinoids, retinoic acid, depression, depressive disorders, and vitamin A. Evidence examined includes (1) case reports; (2) temporal association between onset of depression and exposure to the drug; (3) challenge-rechallenge cases; (4) class effect (other compounds in the same class, like vitamin A, having similar neuropsychiatric effects); (5) dose response; and (6) biologically plausible mechanisms.

STUDY SELECTION

All articles in the literature related to isotretinoin, depression, and suicide were reviewed, as well as articles related to class effect, dose response, and biologic plausibility.

DATA EXTRACTION

Information from individual articles in the literature was extracted, including number of episodes of depression, suicidality, suicide, psychosis, violence and aggression, past psychiatric history, time of onset in relation to isotretinoin usage, medication dosage, duration of treatment, and dechallenge and challenge history.

RESULTS

The literature reviewed is consistent with associations of isotretinoin administration with depression and with suicide in a subgroup of vulnerable individuals.

CONCLUSIONS

The relationship between isotretinoin and depression may have implications for a greater understanding of the neurobiology of affective disorders.

Association of suicide attempts with acne and treatment with isotretinoin: retrospective Swedish cohort study

OBJECTIVE

To assess the risk of attempted suicide before, during, and after treatment with isotretinoin for severe acne.

DESIGN

Retrospective cohort study linking a named patient register of isotretinoin users (1980-9) to hospital discharge and cause of death registers (1980-2001).

SETTING

Sweden, 1980-2001. Population 5756 patients aged 15 to 49 years prescribed isotretinoin for severe acne observed for 17 197 person years before, 2905 person years during, and 87 120 person years after treatment.

MAIN OUTCOME MEASURES

Standardised incidence ratio (observed number divided by expected number of suicide attempts standardised by sex, age, and calendar year), calculated up to three years before, during, and up to 15 years after end of treatment.

RESULTS

128 patients were admitted to hospital for attempted suicide. During the year before treatment, the standardised incidence ratio for attempted suicide was raised: 1.57 (95% confidence interval 0.86 to 2.63) for all (including repeat) attempts and 1.36 (0.65 to 2.50) counting only first attempts. The standardised incidence ratio during and up to six months after treatment was 1.78 (1.04 to 2.85) for all attempts and 1.93 (1.08 to 3.18) for first attempts. Three years after treatment stopped, the observed number of attempts was close to the expected number and remained so during the 15 years of follow-up: standardised incidence ratio 1.04 (0.74 to 1.43) for all attempts and 0.97 (0.64 to 1.40) for first attempts. Twelve (38%) of 32 patients who made their first suicide attempt before treatment made a new attempt or committed suicide thereafter. In contrast, 10 (71%) of the 14 who made their first suicide attempt within six months after treatment stopped made a new attempt or committed suicide during follow-up (two sample test of proportions, P=0.034). The number needed to harm was 2300 new six month treatments per year for one additional first suicide attempt to occur and 5000 per year for one additional repeat attempt.

CONCLUSIONS

An increased risk of attempted suicide was apparent up to six months after the end of treatment with isotretinoin, which motivates a close monitoring of patients for suicidal behaviour for up to a year after treatment has ended. However, the risk of attempted suicide was already rising before treatment, so an additional risk due to the isotretinoin treatment cannot be established. As patients with a history of suicide attempts before treatment made new attempts to a lesser extent than did patients who started such behaviour in connection with treatment, patients with severe acne should not automatically have isotretinoin treatment withheld because of a history of attempted suicide.

13-Cis-retinoic acid decreases hypothalamic cell number in vitro

13-Cis-retinoic acid (13-cis-RA) causes depression-related behavior in mice. Hypothalamic dysregulation has been implicated in clinical depression. In fact, apoptosis of hypothalamic neurons may lead to depression after myocardial infarction. Our objective was to determine if 13-cis-RA affects cultured hypothalamic cell number. Treatment of GT1-7 hypothalamic cells with 10μM 13-cis-RA for 48h decreased cell growth to 45.6±13% of control. To determine if this decrease in cell number was due to 13-cis-RA acting as an oxidant, cells were treated with 13-cis-RA and ascorbic acid or butylated hydroxyanisole (BHA) for 24 or 48h. Neither antioxidant alleviated the inhibitory affects of 13-cis-RA. In addition, 13-cis-RA treatment did not increase superoxide anion production, indicating 13-cis-RA was not acting as an oxidant. To determine if 13-cis-RA was acting via retinoic acid receptors (RARs) to decrease cell number, GT1-7 cells were treated with 13-cis-RA and the RAR pan-antagonist, AGN 193109. Treatment with the RAR-antagonist blocked the ability of 13-cis-RA to decrease cell number, indicating this phenomenon was a RAR-independent mechanism. We hypothesize that the ability of 13-cis-RA to decrease hypothalamic cell number may contribute to the increased depression-related behaviors observed in mice.

Isotretinoin and psychopathology: a review

Isotretinoin, a synthetic oral retinoid that is used against severe nodulocystic acne, has been associated with various psychiatric side effects such as depression, suicidality and psychotic symptoms. A great number of reports on its effects have been published since its introduction into the market. However, a causal relationship has not been established and the link between isotretinoin use and psychiatric events remains controversial. The present paper reviews the available evidence regarding the association of isotretinoin and psychiatric side effects. All published material reporting psychiatric side effects following isotretinoin treatment, including case reports, case series, reports from adverse drug event reporting systems, prospective surveys and retrospective case-control studies, are presented. In addition, the neurobiology of the retinoids and possible biological mechanisms that may lead to psychopathology are described.

The neurobiology of retinoic acid in affective disorders

Current models of affective disorders implicate alterations in norepinephrine, serotonin, dopamine, and CRF/cortisol; however treatments targeted at these neurotransmitters or hormones have led to imperfect resolution of symptoms, suggesting that the neurobiology of affective disorders is incompletely understood. Until now retinoids have not been considered as possible contributors to affective disorders. Retinoids represent a family of compounds derived from vitamin A that perform a large number of functions, many via the vitamin A product, retinoic acid. This signaling molecule binds to specific retinoic acid receptors in the brain which, like the glucocorticoid and thyroid hormone receptors, are part of the nuclear receptor superfamily and regulate gene transcription. Research in the field of retinoic acid in the CNS has focused on the developing brain, in part stimulated by the observation that isotretinoin (13-cis retinoic acid), an isomer of retinoic acid used in the treatment of acne, is highly teratogenic for the CNS. More recent work has suggested that retinoic acid may influence the adult brain; animal studies indicated that the administration of isotretinoin is associated with alterations in behavior as well as inhibition of neurogenesis in the hippocampus. Clinical evidence for an association between retinoids and depression includes case reports in the literature, studies of health care databases, and other sources. A preliminary PET study in human subjects showed that isotretinoin was associated with a decrease in orbitofrontal metabolism. Several studies have shown that the molecular components required for retinoic acid signaling are expressed in the adult brain; the overlap of brain areas implicated in retinoic acid function and stress and depression suggest that retinoids could play a role in affective disorders. This report reviews the evidence in this area and describes several systems that may be targets of retinoic acid and which contribute to the pathophysiology of depression.