Compulsive-like rigidity may be associated with hyposerotonergia and increased kynurenine (KYN) pathway activity. Conversion of tryptophan (TRP) to kynurenine (KYN), which may contribute to hyposerotonergia, is bolstered by inflammation, and could be related to altered gut microbiota composition. Here, we studied these mechanisms in a naturalistic animal model of compulsive-like behavioural rigidity, i.e., large nest building (LNB) in deer mice (Peromyscus sp.).

Twenty-four (24) normal nest building (NNB)- and 24 LNB mice (both sexes) were chronically administered either escitalopram (a selective serotonin reuptake inhibitor; 50 mg/kg/day) or a control solution, with nesting behaviour analysed before and after intervention. After endpoint euthanising, frontal cortices and striata were analysed for TRP and its metabolites, plasma for microbiota derived lipopolysaccharide (LPS) and its binding protein (LBP), and stool samples for microbial DNA.

LNB, but not NNB, decreased after escitalopram exposure. At baseline, LNB associated with reduced frontal cortical TRP concentrations and hyposerotonergia that was unrelated to altered KYN pathway activity. In LNB mice, escitalopram significantly increased frontal-cortical and striatal TRP without altering serotonin concentrations. Treated LNB, compared to untreated LNB- and treated NNB mice, had significantly reduced plasma LPS as well as a microbiome showing a decreased inferred potential to synthesise short-chain fatty acids and degrade TRP.

These findings support the role of altered serotonergic mechanisms, inflammatory processes, and gut microbiome involvement in compulsive-like behavioural rigidity. Our results also highlight the importance of gut-brain crosstalk mechanisms at the level of TRP metabolism in the spontaneous development of such behaviour.

Autoimmune processes have been documented in both childhood and adulthood patients with obsessive-compulsive disorder (OCD), with the pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) representing the paradigm of this model.

Given the limited information available, the present study aimed at assessing the characteristics of adult patients with OCD exposed to a previous group A β-hemolytic Streptococcus infection, together with some peripheral inflammatory biomarkers.

Fifty-two subjects displaying antistreptolysin O (ASO) titer positivity were recruited from a sample of 247 adult OCD outpatients, diagnosed according to DSM-5 criteria and assessed by the Yale-Brown Obsessive-Compulsive Scale. Their clinical features were assessed and compared. The possible relationships between the different parameters were also examined.

Thirty-six subjects who were on medication for OCD showed significantly lower ASO titers than the other. The neutrophil count was positively and negatively related to, respectively, the “distress associated with obsessive thoughts” item and to the patients’ age. The lymphocyte count and folic acid levels were higher in 30 subjects with no perinatal insults.

These results seem to suggest that OCD subjects with ASO titer-positivity show a chronic inflammatory state, in spite of no symptoms or recall of bacterial infections, that might be involved in both the onset and the maintenance of OCD, with immunological alterations being related to symptom dimension to be identified. They also support the notion of possible anti-inflammatory effects of some psychotropic compounds.

Recently, some observational studies suggested that romantic love (RL) might influence the phenotypic expression of obsessive-compulsive disorder (OCD). The aim of the present study was to investigate the impact of different stages of RL on the clinical expression of OCD.

Two hundred and twelve patients with OCD onset related to the development or the termination of a romantic relationship (RR) and who were attending outpatient units at the University Psychiatric Clinic of Pisa, Italy, and seven specialized OCD clinics in Brazil were recruited. The assessment instruments were: the Structured Clinical Interview for DSM-5 Disorders (SCID-5), the Yale OCD Natural History Questionnaire, and the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). Participants were divided into two groups (love-precipitated [LP-OCD] and break-up OCD [BU-OCD]).

The total Y-BOCS and obsessions and compulsions subscales scores were similar and indicative of severe OCD in the two groups. The average age of onset was significantly lower in the BU-OCD group, perhaps reflecting a vulnerability of the brain’s maturational stages to “undesirable” events in young individuals at risk for OCD. A trend towards aggression and symmetry, and ordering and rearrangement dimensions in BU-OCD patients emerged, possibly reflecting an amplification of some normal features of a RR.

Our findings suggest that different stages of RL may influence some features of OCD, namely the age of onset and specific dimensions. Again, RL poses the risk of developing this pathological condition in vulnerable individuals. Further research on the topic should be encouraged.

There is a lack of large-scale studies exploring labor market marginalization (LMM) among individuals diagnosed with bipolar disorder (BD). We aimed to investigate the association of BD with subsequent LMM in Sweden, and the effect of sex on LMM in BD.

Individuals aged 19–60 years living in Sweden with a first-time BD diagnosis between 2007 and 2016 (n = 25 231) were followed from the date of diagnosis for a maximum of 14 years. Risk of disability pension (DP), long-term sickness absence (SA) (>90 days), and long-term unemployment (>180 days) was compared to a matched comparison group from the general population, matched 1:5 on sex and birth year (n = 126 155), and unaffected full siblings (n = 24 098), using sex-stratified Cox regression analysis, yielding hazard ratios (HRs) with 95% confidence intervals (CIs).

After adjusting for socioeconomic factors, baseline labor market status, and comorbid disorders, individuals with BD had a significantly higher risk of DP compared to the general population (HR = 16.67, 95% CI 15.33–18.13) and their unaffected siblings (HR = 5.54, 95% CI 4.96–6.18). Individuals with BD were also more likely to experience long-term SA compared to the general population (HR = 3.19, 95% CI 3.09–3.30) and their unaffected siblings (HR = 2.83, 95% CI 2.70–2.97). Moreover, individuals diagnosed with BD had an elevated risk of long-term unemployment relative to both comparison groups (HR range: 1.75–1.78). Men with BD had a higher relative risk of SA and unemployment than women. No difference was found in DP.

Individuals with BD face elevated risks of LMM compared to both the general population and unaffected siblings.

Research evidence has established an association of obsessive-compulsive disorder (OCD) with suicidal thoughts and suicide attempts. However, further investigation is required to determine whether individuals with OCD have higher risk of death by suicide compared with those without OCD.

Of the entire Taiwanese population, between 2003 and 2017, 56,977 individuals with OCD were identified; they were then matched at a 1:4 ratio with 227,908 non-OCD individuals on the basis of their birth year and sex. Suicide mortality was assessed between 2003 and 2017 for both groups. Time-dependent Cox regression models were used to investigate the difference in suicide risk between individuals with versus without OCD.

After adjustment for major psychiatric comorbidities (i.e., schizophrenia, bipolar disorder and major depressive disorder), the OCD group had higher risk of suicide (hazard ratio: 1.97, 95% confidence interval: 1.57–2.48) during the follow-up compared with the comparison group. Furthermore, OCD severity, as indicated by psychiatric hospitalizations due to OCD, was positively correlated with suicide risk.

Regardless of the existence of major psychiatric comorbidities, OCD was found to be an independent risk factor for death by suicide. A suicide prevention program specific to individuals with OCD may be developed in clinical practice in the future.

The change in symptoms necessary to be clinically relevant in obsessive-compulsive disorder (OCD) is currently unknown. In this study, we aimed to create an empirically validated threshold for clinical significance or minimal important difference (MID).

We analyzed individual participant data from short-term, double-blind, placebo-controlled registration trials of selective serotonin reuptake inhibitors in adult OCD patients. Data were collected from baseline to week 12. We used equipercentile linking to equate changes in the Clinical Global Impression (CGI) scale to changes in the Yale-Brown Obsessive-Compulsive Scale (YBOCS). We defined the MID as the YBOCS change linked to a CGI improvement of 3 (defined as “minimal improvement”).

We included 7 trials with a total of 1216 patients. The CGI-scores and YBOCS were moderately to highly correlated. The MID corresponded to 4.9 YBOCS points (95% CI 4.4–5.4) for the full sample, or a 24% YBOCS-decrease compared to baseline. The MID varied with baseline severity, being lower in the group with mild symptoms and higher in the group with severe symptoms.

By linking the YBOCS to the CGI-I, this is the first study to propose an MID in OCD trials. Having a clearly defined MID can guide future clinical research and help interpretation of efficacy of existing interventions. Our results are clinician-based; however, there is further need for patient-reported outcomes as anchor to the YBOCS.

Obsessive-compulsive disorder (OCD) symptoms are hypothesized to be driven by two core motivations: harm avoidance and incompleteness. While cognitive-behavioural therapy (CBT) is an effective treatment for OCD, many posit that OCD presentations characterized by high incompleteness may be harder to treat. The relationship between the core motivations and treatment outcomes remains to be further explored.

To investigate if harm avoidance and incompleteness decrease across group CBT and to examine the relationship between treatment outcomes and both baseline and changes in harm avoidance and incompleteness throughout treatment.

A naturalistic sample of 65 adult out-patients with OCD completed self-report questionnaires measuring OCD symptom severity and the core motivations before, during, and after 12 weeks of group CBT for OCD.

Harm avoidance and incompleteness scores significantly decreased from pre- to post-treatment. Pre-treatment harm avoidance and incompleteness levels did not predict post-treatment symptom severity, but changes in the core motivations throughout treatment were significant predictors of treatment outcome. Specifically, reductions in harm avoidance across treatment and reductions in incompleteness early in treatment, were associated with better treatment outcomes.

Participants who completed group CBT for OCD experienced modest reductions in the core motivations thought to maintain OCD symptoms and these changes predicted better outcomes. However, pre-treatment levels of harm avoidance and incompleteness do not appear to moderate treatment outcome.

Although numerous studies have examined the effects of psychological treatments for obsessive-compulsive disorder (OCD), their overall effectiveness remains unclear. We aimed to estimate their overall effect by combining all available randomized controlled trials (RCTs) comparing psychological treatments to control groups for OCD.

We conducted a meta-analysis of 48 RCTs with 55 comparisons published between 1992 and 1 January 2023. The primary outcome was OCD symptom severity, with Hedges' g calculated at post-treatment and follow-up. Random-effects models were employed for all analyses, and the risk of bias was assessed.

In general, psychological treatments demonstrated a significantly large effect (g = −1.14; 95% CI [−1.31 to −0.97]; I2 = 72.23%) on reducing OCD symptom severity post-treatment, this finding remained consistent across measures and after excluding outliers, but lost significance in the sensitivity analysis for only studies with low risk of bias. Type of treatment, control group and treatment format were associated with treatment effects. Moreover, more severe baseline OCD symptom severity predicted higher degree of treatment efficacy. No significant differences were observed in dropout rates between the treatment and control groups. Treatment effects lost significance at 3–6 and 6–12 month follow-ups. 87% of RCTs were rated at high risk of bias.

Psychological treatments are effective in reducing OCD symptom severity. However, caution should be exercised when interpreting these results due to the high heterogeneity and risk of bias across RCTs. Future studies with more rigorous methodology are required, as well as studies examining their long-term effectiveness.

Well-designed evaluations of psychological interventions on psychiatric intensive care units (PICUs) are a rarity.

To evaluate the effectiveness of cognitive behaviour therapy for intrusive taboo thoughts with a patient diagnosed with bipolar affective disorder admitted to a PICU due to significant ongoing risk of harm to self.

This was a four-phase ABC plus community follow-up (D) mixed methods n=1 single case experimental design. Four idiographic measures were collected daily across four phases; the baseline (A) was during PICU admission, the first treatment phase (B) was behavioural on the PICU, the second treatment phase (C) was cognitive on an acute ward and the follow-up phase (D) was conducted in the community. Four nomothetic measures were taken on admission, on discharge from the PICU, discharge from the acute ward and then at 4-week follow-up. The participant was also interviewed at follow-up using the Change Interview.

Compared with baseline, the behavioural and the cognitive interventions appeared effective in terms of improving calmness, optimism and rumination, but the effects on sociability were poor. There was evidence across idiographic and nomothetic outcomes of a relapse during the follow-up phase in the community. Eleven idiographic changes were reported in the interview and these tended to be unexpected, related to the therapy and personally important.

Single case methods can be responsive to tracking the progress of patients moving through in-patient pathways and differing modules of evidence-based interventions. There is a real need to implement robust outcome methodologies on PICUs to better evaluate the psychological aspects of care in this context.