Aligning climate scenarios to emissions inventories shifts global benchmarks.

Taking stock of global progress towards achieving the Paris Agreement requires consistently measuring aggregate national actions and pledges against modelled mitigation pathways1. However, national greenhouse gas inventories (NGHGIs) and scientific assessments of anthropogenic emissions follow different accounting conventions for land-based carbon fluxes resulting in a large difference in the present emission estimates2,3, a gap that will evolve over time. Using state-of-the-art methodologies4 and a land carbon-cycle emulator5, we align the Intergovernmental Panel on Climate Change (IPCC)-assessed mitigation pathways with the NGHGIs to make a comparison. We find that the key global mitigation benchmarks become harder to achieve when calculated using the NGHGI conventions, requiring both earlier net-zero CO2 timing and lower cumulative emissions. Furthermore, weakening natural carbon removal processes such as carbon fertilization can mask anthropogenic land-based removal efforts, with the result that land-based carbon fluxes in NGHGIs may ultimately become sources of emissions by 2100. Our results are important for the Global Stocktake6, suggesting that nations will need to increase the collective ambition of their climate targets to remain consistent with the global temperature goals.

Abrupt increase in harvested forest area over Europe after 2015.

Forests provide a series of ecosystem services that are crucial to our society. In the European Union (EU), forests account for approximately 38% of the total land surface1. These forests are important carbon sinks, and their conservation efforts are vital for the EU's vision of achieving climate neutrality by 20502. However, the increasing demand for forest services and products, driven by the bioeconomy, poses challenges for sustainable forest management. Here we use fine-scale satellite data to observe an increase in the harvested forest area (49 per cent) and an increase in biomass loss (69 per cent) over Europe for the period of 2016-2018 relative to 2011-2015, with large losses occurring on the Iberian Peninsula and in the Nordic and Baltic countries. Satellite imagery further reveals that the average patch size of harvested area increased by 34 per cent across Europe, with potential effects on biodiversity, soil erosion and water regulation. The increase in the rate of forest harvest is the result of the recent expansion of wood markets, as suggested by econometric indicators on forestry, wood-based bioenergy and international trade. If such a high rate of forest harvest continues, the post-2020 EU vision of forest-based climate mitigation may be hampered, and the additional carbon losses from forests would require extra emission reductions in other sectors in order to reach climate neutrality by 20503.

Treatment-resistant OCD: Pharmacotherapies in adults.

Serotonin reuptake inhibitor (SRI) medications are well established as first-line pharmacotherapeutic treatment for Obsessive-Compulsive Disorder (OCD). However, despite the excellent safety profile and demonstrated efficacy of these medications, a substantial proportion of individuals with OCD fail to attain sufficient benefit from SRIs. In this narrative review, we discuss clinical features of OCD that have been associated with poorer response to SRIs, and we present pharmacotherapeutic interventions that have been explored as augmenting or alternative treatments for treatment-resistant OCD. We additionally highlight non-SRI interventions for OCD that are currently under investigation. Pharmacotherapeutic interventions were identified via expert consensus. To assess the evidence base for individual pharmacotherapies, targeted searches for relevant English-language publications were performed on standard biomedical research databases, including MEDLINE. Information relevant to ongoing registered clinical trials in OCD was obtained by search of ClinicalTrials.gov. Pharmacotherapies are grouped for review in accordance with the general principles of Neuroscience-based Nomenclature (NbN). Clinical features of OCD that may suggest poorer response to SRI treatment include early age of onset, severity of illness, duration of untreated illness, and the presence of symmetry/ordering or hoarding-related symptoms. Based on evolving pathophysiologic models of OCD, diverse agents engaging serotonin, dopamine, norepinephrine, glutamate, and anti-inflammatory pathways have been explored as alternative or adjunctive therapies for treatment-resistant OCD and have at least preliminary evidence of efficacy. Medications with dopamine antagonist activity remain the most robustly evidence-based of augmenting interventions, yet dopamine antagonists benefit only a minority of those who try them and carry elevated risks of adverse effects. Interventions targeting glutamatergic and anti-inflammatory pathways are less well evidenced, but may offer more favorable benefit to risk profiles. Ongoing research should explore whether specific interventions may benefit individuals with particular features of treatment-resistant OCD.

Assessing response, remission, and treatment resistance in patients with obsessive-compulsive disorder with and without tic disorders: results from a multicenter study.

BACKGROUND: Highlighting the relationship between obsessive-compulsive disorder (OCD) and tic disorder (TD), two highly disabling, comorbid, and difficult-to-treat conditions, Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5) acknowledged a new "tic-related" specifier for OCD, ie, obsessive-compulsive tic-related disorder (OCTD). As patients with OCTD may frequently show poor treatment response, the aim of this multicenter study was to investigate rates and clinical correlates of response, remission, and treatment resistance in a large multicenter sample of OCD patients with versus without tics. METHODS: A sample of 398 patients with a DSM-5 diagnosis of OCD with and without comorbid TD was assessed from 10 different psychiatric departments across Italy. For the purpose of the study, treatment response profiles in the whole sample were analyzed comparing the rates of response, remission, and treatment-resistance as well as related clinical features. Multivariate logistic regressions were performed to identify possible factors associated with treatment response. RESULTS: The remission group was associated with later ages of onset of TD and OCD. Moreover, significantly higher rates of psychiatric comorbidities, TD, and lifetime suicidal ideation and attempts emerged in the treatment-resistant group, with larger degrees of perceived worsened quality of life and family involvement. CONCLUSIONS: Although remission was associated with later ages of OCD and TD onset, specific clinical factors, such as early onset and presence of psychiatric comorbidities and concomitant TD, predicted a worse treatment response with a significant impairment in quality of life for both patients and their caregivers, suggesting a worse profile of treatment response for patients with OCTD.

Obsessive-compulsive disorder, insulin signaling and diabetes - A novel form of physical health comorbidity: The sweet compulsive brain.

BACKGROUND: While a growing body of research highlights a bi-directional link between diabetes and mood disorders, little is known about the relationship between diabetes and obsessive-compulsive disorder (OCD). The aim of the present review is to investigate current evidence linking OCD, insulin-signaling and diabetes. METHODS: A PubMed search was conducted to review all the available studies assessing diabetes, glucose metabolism and insulin-signaling in OCD patients and vice versa. RESULTS: Some clinical and epidemiological studies show a higher prevalence of diabetes in OCD and vice versa compared to the general population. Animal and genetic studies suggest a possible role of insulin-signaling in the pathophysiology of OCD. Deep brain stimulation (DBS) studies suggest that abnormal dopaminergic transmission in the striatum may contribute to impaired insulin sensitivity in OCD. While DBS seems to increase insulin sensitivity, a possible protective role of serotonin reuptake-inhibitors on diabetic risk needs further studies. CONCLUSION: Despite their preliminary nature, these data highlight the importance of further investigations aimed at assessing metabolic features in OCD patients and OCD symptoms in diabetes patients to understand the impact of each condition on the pathophysiology and course of the other. Understanding the role of insulin in the obsessive-compulsive brain could open new treatment pathways for OCD.

Land-based measures to mitigate climate change: Potential and feasibility by country.

Land-based climate mitigation measures have gained significant attention and importance in public and private sector climate policies. Building on previous studies, we refine and update the mitigation potentials for 20 land-based measures in >200 countries and five regions, comparing "bottom-up" sectoral estimates with integrated assessment models (IAMs). We also assess implementation feasibility at the country level. Cost-effective (available up to $100/tCO2 eq) land-based mitigation is 8-13.8 GtCO2 eq yr-1 between 2020 and 2050, with the bottom end of this range representing the IAM median and the upper end representing the sectoral estimate. The cost-effective sectoral estimate is about 40% of available technical potential and is in line with achieving a 1.5°C pathway in 2050. Compared to technical potentials, cost-effective estimates represent a more realistic and actionable target for policy. The cost-effective potential is approximately 50% from forests and other ecosystems, 35% from agriculture, and 15% from demand-side measures. The potential varies sixfold across the five regions assessed (0.75-4.8 GtCO2eq yr-1 ) and the top 15 countries account for about 60% of the global potential. Protection of forests and other ecosystems and demand-side measures present particularly high mitigation efficiency, high provision of co-benefits, and relatively lower costs. The feasibility assessment suggests that governance, economic investment, and socio-cultural conditions influence the likelihood that land-based mitigation potentials are realized. A substantial portion of potential (80%) is in developing countries and LDCs, where feasibility barriers are of greatest concern. Assisting countries to overcome barriers may result in significant quantities of near-term, low-cost mitigation while locally achieving important climate adaptation and development benefits. Opportunities among countries vary widely depending on types of land-based measures available, their potential co-benefits and risks, and their feasibility. Enhanced investments and country-specific plans that accommodate this complexity are urgently needed to realize the large global potential from improved land stewardship.

Early onset obsessive-compulsive disorder: the biological and clinical phenotype.

Moving from a behavioral-based to a biological-based classification of mental disorders is a crucial step toward a precision-medicine approach in psychiatry. In the last decade, a big effort has been made in order to stratify genetic, immunological, neurobiological, cognitive, and clinical profiles of patients. Making the case of obsessive-compulsive disorder (OCD), a lot have been made in this direction. Indeed, while the Diagnostic and Statistical Manual of Mental Disorders (DSM) diagnosis of OCD aimed to delineate a homogeneous group of patients, it is now clear that OCD is instead an heterogeneous disorders both in terms of neural networks, immunological, genetic, and clinical profiles. In this view, a convergent amount of literature, in the last years, indicated that OCD patients with an early age at onset seem to have a specific clinical and biological profile, suggesting it as a neurodevelopmental disorder. Also, these patients tend to have a worse outcome respect to adult-onset patients and there is growing evidence that early-interventions could potentially improve their prognosis. Therefore, the aim of the present paper is to review the current available genetic, immunological, neurobiological, cognitive, and clinical data in favor of a more biologically precise subtype of OCD: the early-onset subtype. We also briefly resume current available recommendations for the clinical management of this specific population.

Suicidal ideation and suicidal attempts in patients with obsessive-compulsive tic-related disorder vs obsessive-compulsive disorder: results of a multicenter Italian study.

BACKGROUND: Obsessive-compulsive disorder (OCD) and tic disorder (TD) represent highly disabling, chronic and often comorbid psychiatric conditions. While recent studies showed a high risk of suicide for patients with OCD, little is known about those patients with comorbid TD (OCTD). Aim of this study was to characterize suicidal behaviors among patients with OCD and OCTD. METHODS: Three hundred and thirteen outpatients with OCD (n = 157) and OCTD (n = 156) were recruited from nine different psychiatric Italian departments and assessed using an ad-hoc developed questionnaire investigating, among other domains, suicide attempt (SA) and ideation (SI). The sample was divided into four subgroups: OCD with SA (OCD-SA), OCD without SA (OCD-noSA), OCTD with SA (OCTD-SA), and OCTD without SA (OCTD-noSA). RESULTS: No differences between groups were found in terms of SI, while SA rates were significantly higher in patients with OCTD compared to patients with OCD. OCTD-SA group showed a significant male prevalence and higher unemployment rates compared to OCD-SA and OCD-noSA sample. Both OCTD-groups showed an earlier age of psychiatric comorbidity onset (other than TD) compared to the OCD-SA sample. Moreover, patients with OCTD-SA showed higher rates of other psychiatric comorbidities and positive psychiatric family history compared to the OCD-SA group and to the OCD-noSA groups. OCTD-SA and OCD-SA samples showed higher rates of antipsychotics therapies and treatment resistance compared to OCD-noSA groups. CONCLUSIONS: Patients with OCTD vs with OCD showed a significantly higher rate of SA with no differences in SI. In particular, OCTD-SA group showed different unfavorable epidemiological and clinical features which need to be confirmed in future prospective studies.

New pharmacological and neuromodulation approaches for impulsive-compulsive behaviors in Parkinson's disease.

INTRODUCTION: A significant proportion of patients with Parkinson's disease (PD) display a set of impulsive-compulsive behaviors at some point during the course of illness. These behaviors range from the so-called behavioral addictions to dopamine dysregulation syndrome, punding and hoarding disorders. These behaviors have been consistently linked to the use of dopaminergic medications used to treat PD motor symptoms (dopamine agonists, levodopa, and other agents) and less consistently to neuromodulation techniques such as deep brain stimulation (DBS). Since there are still no approved treatments for these conditions, their pharmacological management is still a big challenge for clinicians. METHODS: We conducted an extensive review of current pharmacological and neuromodulation literature for the management of impulsive-compulsive disorders in PD patients. RESULTS: Pharmacological treatment approaches for impulsive-compulsive behaviors and DDS in PD patients include reduction of levodopa (LD), reduction/cessation of dopamine agonist (DA), and initiation of infusion therapies (apomorphine infusion and duodopa). Also, atomoxetine, a noradrenergic agent approved for the treatment of attention deficit hyperactivity disorder, showed some interesting preliminary results but there is still a lack of controlled longitudinal studies. Finally, while DBS effects on impulsive-compulsive disorders are still controversial, non-invasive techniques (such as transcranial magnetic stimulation and transcranial direct current stimulation) could have a potential positive effect but, again, there is still a lack of controlled trials. CONCLUSION: Managing impulsivity and compulsivity in PD patients is still a non-evidence-based challenge for clinicians. Controlled trials on promising approaches such as atomoxetine and non-invasive neuromodulation techniques are needed.

Emerging reporting and verification needs under the Paris Agreement: How can the research community effectively contribute?

Greenhouse gas (GHG) emission inventories represent the link between national and international political actions on climate change, and climate and environmental sciences. Inventory agencies need to include, in national GHG inventories, emission and removal estimates based on scientific data following specific reporting guidance under the United Nation Framework Convention on Climate Change (UNFCCC) and the Paris Agreement, using the methodologies defined in the Intergovernmental Panel on Climate Change (IPCC) Guidelines. Often however, research communities and inventory agencies have approached the problem of climate change from different angles and by using terminologies, metrics, rules and approaches that do not always match. This is particularly true dealing with "Land Use, Land-Use Change and Forestry" (LULUCF), the most challenging among the inventory sectors to deal with, mainly because of high level of complexity of its carbon dynamics and the difficulties in disaggregating the fluxes between those caused by natural and anthropogenic processes. In this paper, we facilitate the understanding by research communities of the current (UNFCCC) and future (under the Paris Agreement) reporting requirements, and we identify the main issues and topics that should be considered when targeting improvement of the GHG inventory. In relation to these topics, we describe where and how the research community can contribute to producing useful inputs, data, methods and solutions for inventory agencies and policy makers, on the basis of available literature. However, a greater effort by both communities is desirable for closer cooperation and collaboration, for data sharing and the understanding of respective and common aims.

The impact of interventions in the global land and agri-food sectors on Nature's Contributions to People and the UN Sustainable Development Goals.

Interlocked challenges of climate change, biodiversity loss, and land degradation require transformative interventions in the land management and food production sectors to reduce carbon emissions, strengthen adaptive capacity, and increase food security. However, deciding which interventions to pursue and understanding their relative co-benefits with and trade-offs against different social and environmental goals have been difficult without comparisons across a range of possible actions. This study examined 40 different options, implemented through land management, value chains, or risk management, for their relative impacts across 18 Nature's Contributions to People (NCPs) and the 17 Sustainable Development Goals (SDGs). We find that a relatively small number of interventions show positive synergies with both SDGs and NCPs with no significant adverse trade-offs; these include improved cropland management, improved grazing land management, improved livestock management, agroforestry, integrated water management, increased soil organic carbon content, reduced soil erosion, salinization, and compaction, fire management, reduced landslides and hazards, reduced pollution, reduced post-harvest losses, improved energy use in food systems, and disaster risk management. Several interventions show potentially significant negative impacts on both SDGs and NCPs; these include bioenergy and bioenergy with carbon capture and storage, afforestation, and some risk sharing measures, like commercial crop insurance. Our results demonstrate that a better understanding of co-benefits and trade-offs of different policy approaches can help decision-makers choose the more effective, or at the very minimum, more benign interventions for implementation.

Which practices co-deliver food security, climate change mitigation and adaptation, and combat land degradation and desertification?

There is a clear need for transformative change in the land management and food production sectors to address the global land challenges of climate change mitigation, climate change adaptation, combatting land degradation and desertification, and delivering food security (referred to hereafter as "land challenges"). We assess the potential for 40 practices to address these land challenges and find that: Nine options deliver medium to large benefits for all four land challenges. A further two options have no global estimates for adaptation, but have medium to large benefits for all other land challenges. Five options have large mitigation potential (>3 Gt CO2 eq/year) without adverse impacts on the other land challenges. Five options have moderate mitigation potential, with no adverse impacts on the other land challenges. Sixteen practices have large adaptation potential (>25 million people benefit), without adverse side effects on other land challenges. Most practices can be applied without competing for available land. However, seven options could result in competition for land. A large number of practices do not require dedicated land, including several land management options, all value chain options, and all risk management options. Four options could greatly increase competition for land if applied at a large scale, though the impact is scale and context specific, highlighting the need for safeguards to ensure that expansion of land for mitigation does not impact natural systems and food security. A number of practices, such as increased food productivity, dietary change and reduced food loss and waste, can reduce demand for land conversion, thereby potentially freeing-up land and creating opportunities for enhanced implementation of other practices, making them important components of portfolios of practices to address the combined land challenges.

Addicted to compulsion: assessing three core dimensions of addiction across obsessive-compulsive disorder and gambling disorder.

OBJECTIVE: Several studies suggested that obsessive-compulsive disorder (OCD) patients display increased impulsivity, impaired decision-making, and reward system dysfunction. In a Research Domain Criteria (RDoC) perspective, these findings are prototypical for addiction and have led some authors to view OCD as a behavioral addiction. Thus, the aim of this study was to investigate similarities and differences on impulsivity, decision-making, and reward system, as core dimensions of addiction, across OCD and gambling disorder (GD) patients. METHODS: Forty-four OCD patients, 26 GD patients, and 40 healthy controls (HCs) were included in the study. Impulsivity was assessed through the Barratt Impulsiveness Scale, decision-making through the Iowa Gambling Task, and reward system through a self-report clinical instrument (the Shaps-Hamilton Anhedonia Scale) assessing hedonic tone and through an olfactory test assessing hedonic appraisal to odors. RESULTS: Both OCD and GD patients showed increased impulsivity when compared to HCs. More specifically, the OCD patients showed cognitive impulsivity, and the GD patients showed both increased cognitive and motor impulsivity. Furthermore, both OCD and GD patients showed impaired decision-making performances when compared to HCs. Finally, GD patients showed increased anhedonia and blunted hedonic response to pleasant odors unrelated to gambling or depression/anxiety symptoms, while OCD patients showed only increased anhedonia levels related to OC and depression/anxiety symptoms. CONCLUSION: OCD patients showed several similarities and some differences with GD patients when compared to HCs on impulsivity, decision-making, and reward system, three core dimensions of addiction. These results could have relevant implications for the research of new treatment targets for OCD.

Lifetime bipolar disorder comorbidity and related clinical characteristics in patients with primary obsessive compulsive disorder: a report from the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS).

INTRODUCTION: Bipolar disorder (BD) and obsessive compulsive disorder (OCD) are prevalent, comorbid, and disabling conditions, often characterized by early onset and chronic course. When comorbid, OCD and BD can determine a more pernicious course of illness, posing therapeutic challenges for clinicians. Available reports on prevalence and clinical characteristics of comorbidity between BD and OCD showed mixed results, likely depending on the primary diagnosis of analyzed samples. METHODS: We assessed prevalence and clinical characteristics of BD comorbidity in a large international sample of patients with primary OCD (n = 401), through the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS) snapshot database, by comparing OCD subjects with vs without BD comorbidity. RESULTS: Among primary OCD patients, 6.2% showed comorbidity with BD. OCD patients with vs without BD comorbidity more frequently had a previous hospitalization (p < 0.001) and current augmentation therapies (p < 0.001). They also showed greater severity of OCD (p < 0.001), as measured by the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). CONCLUSION: These findings from a large international sample indicate that approximately 1 out of 16 patients with primary OCD may additionally have BD comorbidity along with other specific clinical characteristics, including more frequent previous hospitalizations, more complex therapeutic regimens, and a greater severity of OCD. Prospective international studies are needed to confirm our findings.

Sexual Arousal in Obsessive-Compulsive Disorder With and Without Contamination/Washing Symptoms: A Moderating Role of Disgust Sensitivity.

Different findings would indicate that obsessive-compulsive disorder (OCD), a common psychiatric condition, might significantly impair intimate relationships and sexual well-being. The aim of the present study was to ascertain whether OCD outpatients with contamination/washing symptoms experience a lower sexual arousal than those experiencing other symptoms. In addition, we explored whether a higher disgust propensity/sensitivity might moderate the relation between contamination/washing symptoms and impaired sexual arousal. A total of 72 outpatients (27 with contamination/washing symptoms and 45 with other obsessive-compulsive symptoms) were selected for this study and assessed by a battery of specific rating scales. The results highlighted how OCD patients with contamination/washing symptoms and higher disgust sensitivity showed an increased propensity to inhibition due to threat of sexual performance failure and consequences. It may be speculated that the disgust sensitivity may be a mechanism involved in the impairment of this well-being domain. In conclusion, these findings suggest that the sexual wellbeing should be evaluated during routine clinical evaluation of OCD patients.

Impulsivity and decision-making in obsessive-compulsive disorder after effective deep brain stimulation or treatment as usual.

OBJECTIVE: Impulsivity and impaired decision-making have been proposed as obsessive-compulsive disorder (OCD) endophenotypes, running in OCD and their healthy relatives independently of symptom severity and medication status. Deep brain stimulation (DBS) targeting the ventral limb of the internal capsule (vALIC) and the nucleus accumbens (Nacc) is an effective treatment strategy for treatment-refractory OCD. The effectiveness of vALIC-DBS for OCD has been linked to its effects on a frontostriatal network that is also implicated in reward, impulse control, and decision-making. While vALIC-DBS has been shown to restore reward dysfunction in OCD patients, little is known about the effects of vALIC-DBS on impulsivity and decision-making. The aim of the study was to compare cognitive impulsivity and decision-making between OCD patients undergoing effective vALIC-DBS or treatment as usual (TAU), and healthy controls. METHODS: We used decision-making performances under ambiguity on the Iowa Gambling Task and reflection impulsivity on the Beads Task to compare 20 OCD patients effectively treated with vALIC-DBS, 40 matched OCD patients undergoing effective TAU (medication and/or cognitive behavioural therapy), and 40 healthy subjects. Effective treatment was defined as at least 35% improvement of OCD symptoms. RESULTS: OCD patients, irrespective of treatment modality (DBS or TAU), showed increased reflection impulsivity and impaired decision-making compared to healthy controls. No differences were observed between OCD patients treated with DBS or TAU. CONCLUSION: OCD patients effectively treated with vALIC-DBS or TAU display increased reflection impulsivity and impaired decision-making independent of the type of treatment.

TiO2 nanoparticles in seawater: Aggregation and interactions with the green alga Dunaliella tertiolecta.

Titanium dioxide nanoparticles (TiO2 NPs) have been widely employed in industrial applications, thus rising concern about their impact in the aquatic environment. In this study we investigated the chemical behaviour of TiO2 NPs in the culture medium and its effect on the green alga Dunaliella tertiolecta, in terms of growth inhibition, oxidative stress, ROS (Reactive Oxygen Species) accumulation and chlorophyll content. In addition, the influence of exopolymeric substances (EPS) excreted by the microalgae on the stability of NPs has been evaluated. The physicochemical characterization showed a high propensity of TiO2 NPs to form micrometric-sized aggregates within 30min, large enough to partially settle to the bottom of the test vessel. Indeed, an increasing amount of TiO2 particles settled out with time, but the presence of EPS seemed to mitigate this behaviour in the first 6h of exposure where the main effects in D. tertiolecta were observed. TiO2 NPs did not inhibit the 72-h growth rate of D. tertiolecta, nor affected the cellular chlorophyll concentration in the range 0.01-10mgL-1. The time-course of ROS production showed an initial transient increase of ROS in TiO2 NP-exposed algae compared to the control, concomitant with an enhancement of catalase activity. Interestingly, intracellular ROS was a small fraction of total ROS, the highest amount being extracellular. The occurrence of cell-mediated chemical transformations of TiO2 NPs in the external medium, related to the presence of EPS, has been evaluated. Our results showed that carbohydrates were the major component of EPS, whereas proteins of medium molecular weight (20-80kDa) were preferentially bound to TiO2 NPs, likely influencing their biological fate.

Emerging drugs to treat obsessive-compulsive disorder.

INTRODUCTION: Obsessive-compulsive disorder (OCD) is a chronic and disabling neuropsychiatric disorder with a lifetime prevalence of approximately 1 - 2% and a rate of treatment resistance of 40%. Other disorders have been related to OCD and have been grouped together in a separate DSM-5 chapter, hypothesizing the existence of an 'OC spectrum', showing a paradigm shift in the conceptualization of the disorder. AREAS COVERED: A review of the most important and recent neurobiological findings that sustain the hypothesis of a more sophisticated model of the disorder is provided, together with a brief overview of the most relevant pharmacological animal models of OCD and its first-line treatments. Current research goals, new compounds tested and the rationale behind the development of these new pharmacologic agents are then explained and reviewed. EXPERT OPINION: In the past years, no effective novel compounds have emerged for the treatment of OCD, even if many efforts has been made in the study of its neurobiological underpinnings. Relevant changes in the conceptualization of the disorder, suggested by interesting new neurobiological evidences, may result helpful in the development of new treatments.

Hypochondriasis and obsessive-compulsive disorder in schizophrenic patients treated with clozapine vs other atypical antipsychotics.

OBJECTIVE: The aim of the study was to investigate the prevalence rates of obsessive-compulsive disorder (OCD) and hypochondriasis in schizophrenic patients treated with atypical antipsychotics (AAPs) and to investigate the different comorbidity rates of OCD and hypochondriasis between clozapine-treated patients and patients treated with other AAPs. METHODS: We therefore recruited 60 schizophrenic patients treated with clozapine or other AAPs. We assessed the prevalence rates of OCD or OC symptoms and hypochondriasis or hypochondriac symptoms in the whole group of patients and in clozapine-treated patients versus patients treated with other AAPs. RESULTS: Schizophrenic patients had a higher comorbidity rate of OCD (26.6% vs 1-3%) and hypochondriasis (20% vs 1%) than the general population. These comorbidities were more frequent in schizophrenic patients treated with clozapine versus patients treated with other AAPs (36.7% vs 16.7% and 33.3% vs 6.7%). Clozapine-treated patients showed a higher mean Y-BOCS and HY-BOCS score when compared to patients treated with other AAPs (10.90 vs 5.90, p = .099; 15.40 vs 8.93, p = .166). A statistical significant correlation was found between the Y-BOCS and HY-BOCS scores of the whole group (r = .378, p = 0.03). Furthermore, we found an inverse correlation between the global level of functioning and the diagnosis of hypochondriasis (p = .048) and the severity of hypochondriac symptoms (p = .047). CONCLUSIONS: Hypochondriasis could represent an important clinical feature of schizophrenic patients treated with atypical antipsychotics, and further research is needed in this field.