Author Correction: Serotonin transporter binding is increased in Tourette syndrome with Obsessive Compulsive Disorder.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Serotonin transporter binding is increased in Tourette syndrome with Obsessive Compulsive Disorder.

While the importance of the serotonergic system in obsessive compulsive disorder (OCD) is well established, its role in Tourette syndrome (TS) is uncertain. Particularly in TS patients with comorbid OCD (TS + OCD), decreased serotonin transporter (SERT) binding has been suggested. Here, we investigated for the first time SERT binding in TS patients with and without OCD (TS - OCD) compared to both healthy controls (HC) and OCD patients as well as the influence of escitalopram using the potent SERT imaging ligand [123I]2-((2-((dimethylamino)methyl)phenyl)thio)-5-iodophenylamine ([123I]ADAM) and single-photon emission tomography (SPECT). We included 33 adult subjects (10 HC, 10 TS - OCD, 8 TS + OCD and 5 OCD). In patients with OCD and TS + OCD [123I]ADAM SPECT was repeated after 12-16 weeks treatment with escitalopram. SERT binding was normal in patients with OCD and TS - OCD, but significantly increased (p < 0.05) in those with TS + OCD, particularly in caudate and midbrain compared to both HC and TS - OCD. Treatment with escitalopram resulted in a significant overall reduction in SERT binding (range, 19 to 79%, p values between 0.0409 and <0.0001) without any correlation with clinical improvement. Our results provide further evidence that alterations in the serotonergic system in TS are related to comorbid OCD and do not represent the primary cause of the disease.

Meta-analysis: hoarding symptoms associated with poor treatment outcome in obsessive-compulsive disorder.

DSM-5 recognizes hoarding disorder as distinct from obsessive-compulsive disorder (OCD), codifying a new consensus. Hoarding disorder was previously classified as a symptom of OCD and patients received treatments designed for OCD. We conducted a meta-analysis to determine whether OCD patients with hoarding symptoms responded differently to traditional OCD treatments compared with OCD patients without hoarding symptoms. An electronic search was conducted for eligible studies in PubMed. A trial was eligible for inclusion if it (1) was a randomized controlled trial, cohort or case-control study; (2) compared treatment response between OCD patients with and those without hoarding symptoms, or examined response to treatment between OCD symptom dimensions (which typically include hoarding) and (3) examined treatment response to pharmacotherapy, behavioral therapy or their combination. Our primary outcome was differential treatment response between OCD patients with and those without hoarding symptoms, expressed as an odds ratio (OR). Twenty-one studies involving 3039 total participants including 304 with hoarding symptoms were included. Patients with OCD and hoarding symptoms were significantly less likely to respond to traditional OCD treatments than OCD patients without hoarding symptoms (OR=0.50 (95% confidence interval 0.42-0.60), z=-7.5, P<0.0001). This finding was consistent across treatment modalities. OCD patients with hoarding symptoms represent a population in need of further treatment research. OCD patients with hoarding symptoms may benefit more from interventions specifically targeting their hoarding symptoms.