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Lessons from a multicenter, international, large sample size analysis of patients with obsessive–compulsive disorders: an overview of the ICOCS Snapshot studies

Published online by Cambridge University Press:  11 September 2023

Matteo Vismara*
Affiliation:
University of Milan, Department of Mental Health, Department of Biomedical and Clinical Sciences Luigi Sacco, Milan, Italy
Beatrice Benatti
Affiliation:
University of Milan, Department of Mental Health, Department of Biomedical and Clinical Sciences Luigi Sacco, Milan, Italy “Aldo Ravelli” Center for Neurotechnology and Brain Therapeutic, University of Milan, Milan, Italy
Naomi A. Fineberg
Affiliation:
School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK Hertfordshire Partnership University NHS Foundation Trust, Welwyn Garden City, UK University of Cambridge School of Clinical Medicine, Cambridge, UK
Eric Hollander
Affiliation:
Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Montefiore Medical Center, New York, USA
Michael Van Ameringen
Affiliation:
Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Ontario, Canada
Jose M. Menchon
Affiliation:
Psychiatry Unit at the Hospital Universitari de Bellvitge-IDIBELL, University of Barcelona, Cibersam, Barcelona, Spain
Joseph Zohar
Affiliation:
Post-Trauma Center, Research Foundation by the Sheba Medical Center, Tel Aviv University, Sackler School of Medicine, Israel
Bernardo Dell’Osso
Affiliation:
University of Milan, Department of Mental Health, Department of Biomedical and Clinical Sciences Luigi Sacco, Milan, Italy “Aldo Ravelli” Center for Neurotechnology and Brain Therapeutic, University of Milan, Milan, Italy Department of Psychiatry and Behavioral Sciences, Bipolar Disorders Clinic, Stanford University, CA, USA
*
Corresponding author: Matteo Vismara; Email: matteo.vismara@unimi.it
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Abstract

Obsessive–compulsive disorder (OCD) is a prevalent and highly disabling condition, characterized by a range of phenotypic expressions, potentially associated with geo-cultural differences. This article aims to provide an overview of the published studies by the International College of Obsessive-Compulsive Spectrum Disorders, in relation to the Snapshot database which has, over the past 10 years, gathered clinical naturalistic data from over 500 patients with OCD attending various research centers/clinics worldwide. This collaborative effort has provided a multi-cultural worldwide perspective of different socio-demographic and clinical features of patients with OCD. Data on age, gender, smoking habits, age at onset, duration of illness, comorbidity, suicidal behaviors, and pharmacological treatment strategies are presented here, showing peculiar differences across countries.

Type
Review
Creative Commons
Creative Common License - CCCreative Common License - BY
This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited.
Copyright
© The Author(s), 2023. Published by Cambridge University Press

Introduction

Obsessive–compulsive disorder (OCD) is a prevalent and highly disabling mental health condition, characterized by a range of phenotypic expressions.Reference Fineberg, Hollander and Pallanti 1 Recent updates in the Diagnostic and Statistical Manual of Mental Disorders 5 (DSM-5) and in the International Classification of Diseases 11th Revision emphasized the growing significance of OCD, indicating it as the archetypal example of a new spectrum of obsessive–compulsive and related disorders. These changes are expected to provide new impetus in the understanding of the pathophysiology, phenomenology, and therapeutic interventions of OCD and related conditions.

The “Snapshot project” conducted by the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS), in collaboration with the European College of Neuropsychopharmacology-Obsessive Compulsive Research Network (ECNP-OCRN), has, over the past decade, gathered clinical naturalistic data from research sites across the globe—that is, North America (Canada, the United States, and Mexico), Africa (South Africa), Europe (Spain, Italy, Turkey, and Bulgaria), and the Middle East (Israel)—creating a large database of consecutive outpatients affected by OCD. Detailed information about participating centers and assessment procedures have been documented elsewhere.Reference Dell’Osso, Benatti and Buoli 2 Briefly, patients had to be diagnosed as affected by OCD through the administration of the Mini-International Neuropsychiatric InterviewReference Sheehan, Lecrubier and Sheehan 3 and the main socio-demographic and clinical variables were collected by clinicians during assessment or through revision of clinical charts. Data were there incorporated in a common web-database. All centers participating to the ICOCS initiative have a well-established expertise in diagnosing and treating OCD, typically operating as academic or tertiary clinics. A rigorous methodology and consistency were maintained during data collection and diagnostic procedure to minimize potential inter-institutional differences in sampling. In its final version, the database encompassed a total of 504 patients, although the specific subset of patients analyzed in each study might have varied (see Table 1 for details), considering data were elaborated from the database at different times or because of missing data. The present short review of the pooled study data aims to provide an overview of the most relevant findings emerging from the various constituent studies making up the Snapshot database.

Table 1. Overall Results from the ICOCS Snapshot Database Studies

Abbreviations: AAO, age at onset; BD, bipolar disorders; CBT, cognitive-behavioral therapy; CGI-I: Clinical Global Impression, I: Improvement Scale, S: Severity Scale; DOI, duration of illness; DSM, Diagnostic and Statistical Manual of Mental Disorders; MINI, Mini-International Neuropsychiatric Interview; OCSDs, obsessive–compulsive spectrum disorders; OR, odds ratio; SA, suicide attempts; SDS, Sheehan Disability Scale; SNRIs, serotonin norepinephrine reuptake inhibitors; SSRIs, selective serotonin reuptake inhibitors; TCAs, tricyclic antidepressants; Y-BOCS, Yale-Brown Obsessive–Compulsive Scale.

* Differences in sample size depend on missing data for the specific variable investigated in each paper.

** No mean/percentage data available in the original paper.

Findings from the ICOCS database studies

The ICOCS studies have explored the influence of the following variables: age, gender, smoking habits, age at onset, duration of illness, comorbidity, suicidal behaviors, and pharmacological treatment strategies. Published studies and summarized results are outlined in Table 1.

Socio-demographic characteristics

One of the most recent studies from the Snapshot database investigated the influence of gender on OCD.Reference Benatti, Girone and Celebre 4 In line with prior published findings,Reference Benatti, Celebre and Girone 13 , Reference Fontenelle, Mendlowicz and Marques 14 the study revealed that male OCD patients showed a significantly earlier age of onset of symptoms when compared to female counterparts. However, no significant differences in the severity of OCD symptoms were observed between the genders. Additionally, the study noted that females were more likely to be married, living with a partner, and had a lower education level, which could be linked to the later age at OCD onset in this subgroup. Moreover, females were more prominently represented in the group of patients with adult-onset (occurring at or after 18 years of age), while the gender distribution was similar in the childhood (≤13 years) and adolescent-onset (between 13 and 17 years) subgroups.Reference Dell’Osso, Benatti and Hollander 9 This lack of male predominance in the early-onset subgroups contradicts previous literature, which typically shows a higher male rate in such cases.Reference Fontenelle, Mendlowicz and Marques 14 Although the exact mechanisms underlying this phenomenon remain unclear, several lines of evidence suggest that androgens may play a critical role in the onset and exacerbation of certain cases of OCD. In this study, which collected patients from various institutions, it is possible that cultural differences—that need to be further investigated—might have influenced the onset of the illness and mitigated differences between genders.

Mindful of the limitations in knowledge about OCD among the elderly, another study aimed to characterize the clinical presentation of older patients with OCD (≥65 years old), that represented a significant minority (6%) of the overall sample in the ICOCS database. These elderly patients with OCD were more frequently female and exhibited a distinct pattern of illness compared with their younger counterparts, in terms of a later age at onset of OCD and a less frequent use of cognitive behavioral therapy (CBT).Reference Dell’Osso, Benatti and Rodriguez 8 Previous findings regarding geriatric OCD patients are scarce and restricted to a few studies. For instance, a single-center study comparing 32 OCD geriatric patients (≥60 years old) to 601 non-geriatric patients revealed a similar prevalence of elderly patients (5.3%) and, similarly, this subset of patients was also characterized by a later age at onset. Moreover, the elderly patients exhibited fewer concerns related to symmetry, need to know, and counting rituals, while handwashing and fear of sinning were more common.Reference Kohn, Westlake and Rasmussen 15 As in the ICOCS Snapshot dataset, no difference in severity of illness was found across age subgroups.Reference Kohn, Westlake and Rasmussen 15 Conversely, another cross-sectional investigation on 227 subjects with OCD found a negative correlation (r = −0.386, p < 0.001) between age and Yale-Brown Obsessive–Compulsive Scale (YBOCS) score.Reference Brakoulias and Rehn 16

The attitude OCD patients have toward cigarette smoking was another area of investigation in the ICOCS database, revealing that nearly one out of four OCD patients were current smokers (24%, with significant differences across countries). Among this group, females were more prominently represented.Reference Dell’Osso, Nicolini and Lanzagorta 10 Although this prevalence is relatively low when compared to patients with other psychiatric disorders (50%–80% of smokers),Reference Rüther, Bobes and De Hert 17 it is higher when compared to other OCD studies (5.5%–20%).Reference Abramovitch, Pizzagalli and Geller 18 , Reference Sharma, Gale and Fineberg 19 Moreover, current smokers were over represented in patients with comorbid Tourette’s syndrome or tic disorder (compared with former smokers or subjects who never smoked), suggesting a shared impulsive behavior mechanism between pathological behaviors and nicotine use. Interestingly, a higher comorbidity rate with psychiatric and medical conditions emerged in non-smokers when compared to smokers. However, this result cannot be thoroughly explained due to factors such as: i) the specific psychiatric or medical comorbidity should be considered, ii) the small sample size of each subgroup (in the original paper, only the minority of patients—less than 20%—showed a comorbidity), and iii) the inability to establish a causal relationship between smoking and comorbid psychiatric/medical conditions in cross-sectional studies.

Clinical characteristics

Results from the international database analysis investigating age at onset confirmed the well-known early-onset of OCD. Specifically, 21% of patients reported childhood-onset, 36% experienced adolescent-onset, and the minority (43%) had adult-onset OCD.Reference Dell’Osso, Benatti and Hollander 9 Taken as a whole, this study highlighted that the majority of OCD patients experienced symptoms before adulthood (ie, before the age of 18). In addition, childhood- and adolescent-onset patients had been more frequently treated with CBT, compared with adult-onset patients,Reference Dell’Osso, Benatti and Hollander 9 suggesting that CBT is an suitable first-line treatment in mild-to-moderate cases of young OCD patients. 20

Another study conducted by the ICOCS group indicated that an early onset and longer duration of illness were negative predictors of long-term overall outcomes in OCD patients.Reference Dell’Osso, Benatti and Buoli 2 In detail, a longer duration of illness was predictive of lifetime psychiatric hospitalizations and was directly correlated with higher disability in work, social, and family life, as measured through the Sheehan Disability Scale (SDS).Reference Sheehan 21 An early age at illness onset was associated with the need for treatment augmentation of CBT and was inversely correlated with higher social disability. Conversely, panic disorder comorbidity (occurring after the onset of OCD) was correlated with a later age at onset and a shorter duration of illness Reference Dell’Osso, Benatti and Buoli 2, suggesting that this comorbidity is associated with an greater readiness to seek treatment.Reference Goodwin, Koenen and Hellman 22

A recently published study from Brakoulias and colleagues collected data from more than 3,700 participants across seven countries (Australia, Brazil, India, Italy, Japan, South Africa, and Spain) representing the largest international database of OCD in the literature.Reference Brakoulias, Starcevic and Belloch 23 While this paper benefited from a large sample of patients from diverse backgrounds, it had limitations due to data being derived from studies with varying objectives and recruitment methods, resulting in heterogeneous samples. Among the clinical data analyzed in this paper, mean age of onset of OCD was 16.9 years (SD = 4.5, measured in four nations, n = 2,022) with no significant differences across countries. This mean age at onset was lower compared to the mean age at onset reported in the ICOCS database (20.6 years, SD = 10.9, as noted in the paper, Dell’Osso et al., 2013Reference Dell’Osso, Benatti and Buoli 2). This finding underscores once more the typical early onset of OCD and, consequently, the importance of targeting interventions toward childhood age groups.Reference Fontenelle, Nicolini and Brakoulias 24

Comorbidity

Individuals with OCD frequently experience additional psychiatric disorders either concomitantly or at some point during their lifetime. This comorbidity is responsible for negative outcomes such as a higher burden of the disease and reduced responsiveness to treatment.Reference Pallanti, Grassi and Sarrecchia 25

Two reports from the ICOCS have focused on comorbidity rates in OCD.Reference Dell’osso, Vismara and Benatti 6 , Reference Lochner, Fineberg and Zohar 11 The first study reported high cross-sectional co-occurring rates for disorders within the OCD spectrum, including tic disorder (12.5%), body dysmorphic disorder (8.7%), and compulsive self-injurious behaviors (7.4%). This supports the idea of including these conditions in the same spectrum of OC-related disorders, as well as the introduction of the new “tic-related” specifier for OCD in the DSM-5. Among other previously classified DSM-IV-Text Revised Axis I disorders, major depressive disorder, social anxiety disorder, generalized anxiety disorder, and dysthymic disorder were the most prevalent (ranging between 15% and 13%) and the number of comorbid anxiety and mood disorders strongly correlated with the severity of OCD.Reference Lochner, Fineberg and Zohar 11 However, it is important to note that these data may underestimate the rate of comorbid conditions in OCD. In contrast, the international database from Brakoulias, reported higher rates of comorbid conditions: major depressive disorder (50.5%), social phobia (26.4%), specific phobia (25.5%), generalized anxiety disorder (24.0%), hypomanic episode (23.7%), and dysthymia (22.5%).Reference Brakoulias, Starcevic and Belloch 23 The lower rates of psychiatric comorbidity observed in the ICOCS Snapshot database, also compared to previous single-center studies,Reference Stein, Costa and Lochner 26 may reflect that most of the patients included in the Snapshot study were already receiving effective treatment before seeking care at an OCD specialized center. Alternatively, it could be attributed to recall bias due to the single interview method used in the Snapshot study.

A subsequent study from the ICOCS study specifically investigated the lifetime comorbidity of bipolar disorders in patients with primary OCD, showing a 6.2% rate in the ICOCS Snapshot database.Reference Dell’osso, Vismara and Benatti 6 Subjects with comorbid bipolar disorders showed greater severity of OCD, as measured by the YBOCS, and were more likely to have lifetime psychiatric hospitalizations and augmentation pharmacotherapies, which could be related to the greater severity of their illness.

Overall, these comorbidity studies have provided new findings into the rates and patterns of specific comorbidities in OCD patients, highlighting the burden of comorbid conditions as well as the need for targeted therapeutic interventions in specific situations (eg, prescribing high doses of serotonergic antidepressants, which could induce mood elevation episodes in patients with comorbid bipolar disorders).

Suicide

Although OCD has traditionally been associated with a low suicide risk, emerging literature data disconfirmed this assumption, revealing a higher suicide risk for OCD patients compared to the general population.Reference Pellegrini, Maietti and Rucci 27 Snapshot investigations confirmed this perspective, with 15.9% of patients reporting current suicide risk (as assessed with the suicide module [C] of the M.I.N.I.),Reference Benatti, Dell’Osso and Shen 5 and a similar rate (14.6%) reporting suicide attempts at least once during lifetime.Reference Dell’Osso, Benatti and Arici 7 Notably, several risk factors for suicide risk have emerged, suggesting the importance of addressing these factors during clinical interviews. These factors include a higher severity of OCD and related disability, the presence of comorbid medical or psychiatric disorders (especially, major depression and generalized anxiety disorder), and previous psychiatric hospitalizations.Reference Benatti, Dell’Osso and Shen 5 , Reference Dell’Osso, Benatti and Arici 7 When compared to the paper by Brakoulias, it was found that suicidal ideation within the last month was reported by a average of 6.4% of patients, whereas 9.0% reported having attempted suicide in their lifetime.Reference Brakoulias, Starcevic and Belloch 23

Pharmacological treatment

The cross-sectional evaluation conducted by the ICOCS provided insights into the pharmacological treatment strategies employed in various tertiary care settings.Reference Van Ameringen, Simpson and Patterson 12 The results were in alignment with evidence-based treatment guidelines, 20 showing that 77.6% of patients were prescribed a selective serotonin reuptake inhibitor (SSRI) and 50% were utilizing at least one augmentation strategy. Among the augmentation strategies, antipsychotics were most frequently prescribed (30.3%), followed by benzodiazepines (24.9%), and antidepressants other than SSRI (21.9%). Notably, no significant differences were found in mean YBOCS scores or clinical improvement (as measured on the Clinical Global Impression, Improvement [CGI-I]) between specific monotherapy agents and, similarly, between individuals treated with at least one augmentation strategy and those treated with monotherapy. However, those in the augmentation group reported significantly higher SDS scores, indicating that augmentation was associated with a greater degree of functional impairment.Reference Van Ameringen, Simpson and Patterson 12 These results might suggest that augmentation strategies may provide limited therapeutic benefit for individuals who do not respond to first-line treatments for OCD, which challenges the robust evidence from the literature.Reference Albert, Marazziti and Di Salvo 28 However, it is important to consider that these results are based on a cross-sectional analysis, and potential confounding factors should be attentioned. First, patients might be at different stages of treatment—with those on augmentation possibly having more treatment-resistant OCD than those on monotherapy. The lack of difference in symptoms severity might suggest that both groups improved to an equal extent, despite facing a more treatment resistant form of the illness. The lack of improvement between patients on monotherapy compared to those on augmentation could also be influenced by specific characteristics of the study’s patient population, in particular the duration of illness, the number of previous treatment trials, and the increased severity of OCD in this sample—that is, patients recruited from tertiary care settings often have more severe and treatment-resistant forms of OCD, making them less likely to respond to augmentative strategies. Alternatively, the results may point to a “plateau effect” where only a limited degree of improvement can be achieved in individuals who require a next-step treatment.

Geographical/transcultural differences

The ICOCS database analysis provided a valuable trans-cultural worldwide perspective on various socio-demographic and clinical OCD features. This geographic heterogeneity in the sample had several advantages. First, it minimized the risk of possible socio-cultural bias and other confounding factors related to a single catchment area, providing an objective characterization of the phenomena under investigation. Second, it offered an opportunity to explore how cultural variations and specific local factors, especially related to the healthcare system, might influence the clinical course of OCD. Indeed, several sociodemographic differences across countries emerged from the analysis. For instance, female gender was overrepresented only in patients from the Americas (Canada, the United States, and Mexico), whereas other countries showed a more balanced gender distribution.Reference Benatti, Girone and Celebre 4 Of note, the highest number of non-smoking patients was observed in Italy, whereas South Africa showed the highest number of current smoking patients.Reference Dell’Osso, Nicolini and Lanzagorta 10 South African patients also exhibited a larger number of comorbid Axis I when compared to those in Spain,Reference Lochner, Fineberg and Zohar 11 and they were more frequently prescribed monotherapy when compared to patients in Europe or Canada.Reference Van Ameringen, Simpson and Patterson 12 With respect to suicidal behaviors, Italy, South Africa, Israel, Canada, and the United Kingdom had the highest current suicidal risk prevalence,Reference Benatti, Dell’Osso and Shen 5 a phenomenon that partially reflects the highest rate of previous suicide attempts observed in European and South African patients.Reference Dell’Osso, Benatti and Arici 7 Regarding disease burden, patients from Europe showed a higher severity of illness (higher scores on the YBOCS and on the CGI-severity scales) when compared to subjects from Canada; similarly, subjects from Europe showed a higher disability when compared with ones from South Africa (as measured with the SDS).Reference Van Ameringen, Simpson and Patterson 12

Unrevealing the causal relationships responsible of these differences is complex, as several confounding factors might exist and comparative studies on OCD manifestations between countries remain limited. Moreover, ethnic minorities with OCD are often underrepresented in research, as most of the investigations focused on European or American population. Increasing our understanding of geographical and transcultural factors and their impact on the clinical presentation of OCD is, therefore, essential.

While the impact of pathophysiological mechanisms on OCD is well-determined, with core features likely relatively independent of cultural variations, some data suggest that the content of the obsessions may be an exception to this rule.Reference Fontenelle, Mendlowicz and Marques 29 , Reference Nicolini, Salin-Pascual and Cabrera 30 Indeed, religious believes and religiosity seem to affect the type of obsessions and severity of their manifestations, whereas certain “taboo obsessions,” such as those related to sexual orientation, might be culture‐bound as these have mainly been observed in Western cultures and has not been reported in the literature outside of the United StatesReference Williams, Chapman, Simms, Abramowitz, Kay and Storch 31 or in Middle Eastern countries where religious themes are prevalent. In Brazil, a predominance of aggressive obsessions has been described.Reference Petribú and Bastos 32 Geographical differences have also been identified in previous studies that compared the clinical manifestation of OCD between countries. For example, a higher rate of comorbid generalized anxiety disorder and post-traumatic stress disorder were reported in Brazilians meanwhile Americans were more likely to endorse substance abuse disorders.Reference Medeiros, Torres and Boisseau 33 Rates of comorbid lifetime major depressive disorder ranged from around 30% in India and Japan to around 60% in Australia and South Africa, likely reflecting different access to treatment for these comorbid conditions.Reference Brakoulias, Starcevic and Belloch 23 Moreover, the incidence of OCD was lower in Taiwan, and there was a larger proportion of individuals with only obsessions the United States, Canada, Puerto Rico, and New Zealand, compared to Korea, where the proportion of subjects presenting only compulsions was higher than in the other cultural backgrounds.Reference Horwath and Weissman 34 Recent suicidal ideation was most prevalent in the Australian sample (up to 33.2%), while a lifetime history of a suicide attempt was highest in the South African sample (15.9%).Reference Brakoulias, Starcevic and Belloch 23

Access to health care and treatments significantly impacts the clinical presentation of OCD. Geographical differences in treatment approaches were evident in the ICOCS Snapshot sample. A previous paper reported geographical variations in the percentage of subjects not being pharmacologically treated, with 44% OCD patients untreated in Brazil and 38% untreated in Australia. In contrast, countries like Italy, Japan, and Spain showed nearly 100% of patients on pharmacological treatment.Reference Kirmayer, Fung and Rousseau 35 Although no country in the Snapshot database came from a low-income economy, variations in healthcare system, including public versus private options, and public policies regarding access to treatments or subsidies for drug and interventions, likely played a role in the clinical presentation of OCD. Limited access to care can impact disease severity by prolonging the duration of untreated illness. Efforts to favor access to treatment, such as reducing stigma associated with OCD and mental illness in general and increasing investments in mental health, are crucial. Recent literature data have highlighted that minorities with OCD, including Asian/Pacific Islander, Hispanic, Latino, Black, and Multiracial individuals, were often under-treated and underserved in terms of both psychological and psychiatric services compared to non-minorities.Reference Katz, Rufino and Werner 36 Although a clear trend in this direction has not been observed in the Snapshot database (ie, no clear difference between treatment strategies in subjects from South Africa, Mexico, and Israel versus the other countries), this could be attributed to the fact that patients were included from a tertiary-care setting, where access to care is more filtered to selected individuals. Increasing education on mental health disorders and reducing stigma remain of high importance for improving access to effective care in each country. Lastly, geographical variables might be influenced by genetic differences and epigenetic mechanisms (eg, effect of food, environmental exposures), which contribute to different presentation of the disorder.Reference Zai, Barta and Cath 37 Therefore, a thorough evaluation of education background, cultural aspects, access to health services, and the genetic structure of populations, is crucial and should be always taken into account in clinical studies.

Discussion and future perspectives

The ICOCS Snapshot database has the unprecedented privilege to gain a global perspective on the socio-demographic and clinical features of individuals with OCD. The findings from the analysis of this database not only confirm previous literature research but also shed new light on various clinical aspects of OCD. One significant finding is the confirmation that OCD most commonly begins in pre-adult age. This emphasizes the importance of developing specific diagnostic and therapeutic pathways between child and adolescent psychiatrists, in light of the poorer prognosis associated with early-onset OCD.

Gender-related differences emerged in OCD presentation has also been highlighted, underscoring the need to further investigate how gender affects the clinical presentation of the illness and its underlying causes, such as potential influence of sex hormones.

Regarding comorbidity, while the rates of psychiatric comorbidity appeared lower when compared to previous studies, OCD was nonetheless associated with notable culture-specific rates of tobacco smoking and suicide risk. These findings emphasize the importance of addressing these comorbidities in the management of OCD. In terms of treatment, despite evidence from academic clinical trials suggesting augmentative treatments may be effective in OCD, analysis from the Snapshot database challenged this strength of evidence, suggesting that augmentation strategies may have limited therapeutic benefit for those who do not respond to first-line treatments. However, in the clinical practice, combination strategies remain the most preferred treatments in OCD and in other many psychiatric disorders, as the academic clinical trials might not reflect the real-world treatment modalities and effectiveness of medications—because of strict exclusion criteria—and the cross-sectional studies/naturalistic studies might not reflect the real therapeutic effects of medications—because of confounding factors.

For a correct interpretation of these data, potential limitation intrinsic to the selected studies should be considered. First, the studies in the ICOCS Snapshot project were naturalistic and cross-sectional, potentially introducing recall-bias. Moreover, patients were at different stages of illness and were recruited from academic tertiary clinics (where rates of treatment-seeking subjects might be higher, as well as the rate of comorbidities and the severity of illness), therefore they might do not fully reflect the standard of care usually observed elsewhere, and such population may not adequately represent the broader population of individuals with OCD. Lastly, the varying prevalence of co-occurring conditions observed between different countries (eg, cigarette smoking, suicide, and comorbidity) might reflect a difference among those countries independently from OCD.

Of note, the collaborative network of researchers and clinicians involved in the ICOCS project have led to several position papers, including one study on the advances in the treatment of OCD,Reference Fineberg, Hollander and Pallanti 1 on functional interventions as augmentation strategiesReference Varinelli, Caricasole and Pellegrini 38 and a clinician’s guide to face OCD amid the COVID-19 pandemic.Reference Fineberg, Van Ameringen and Drummond 39 Overall, we believe that the past and future collaborative efforts of the ICOCS network will improve the knowledge on OCD, benefiting patients, related caregivers, and treating clinicians.

Future research should investigate the role of additional variables, such as cognitive functions or neurodevelopmental disorders (eg, autism spectrum disorders or attention deficit hyperactivity disorder) which are frequently observed alongside OCD. Transitioning to a longitudinal valuation of the sample could help to establish causal relationship among variables. Additionally, the geographical/transcultural peculiarities highlighted in the ICOCS database analysis underline the need for specific diagnostic and therapeutic strategies tailored to different populations, considering both biological and environmental factors.

Acknowledgments

The authors wish to acknowledge the International College of Obsessive-Compulsive Disorders (www. ICOCS.org) and the European College of Neuropsychopharmacology (ECNP) Obsessive-Compulsive and Related Disorders Research Network (OCRN), who have contributed to the development of this article through network opportunities.

Author contribution

Conceptualization: M.V., B.D.; Supervision: B.D.; Writing—original draft: M.V., B.B.; Writing—review and editing: M.V., B.B., N.A.F., E.H., M.V.A., J.M.M., J.Z., B.D. All authors agreed to the publication of the manuscript in its final version.

Financial support

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Competing interest

N.A.F. declares that in the past 3 years, she has accepted research or networking grants from the UK NIHR, COST Action, Orchard; travel and/or hospitality expenses from the BAP, ECNP, RCPsych, CINP, International Forum of Mood and Anxiety Disorders, World Psychiatric Association, Indian Association for Biological Psychiatry; payment from Elsevier for editorial duties. Previously, she has accepted paid speaking engagements in various industry supported symposia and has recruited patients for various industry-sponsored studies in the field of OCD treatment. She leads an NHS treatment service for OCD. She holds board membership for various registered charities linked to OCD. She gives expert advice on psychopharmacology to the UK MHRA. B.D. has received grant/research support from LivaNova, Inc., Angelini and Lundbeck and Lecture Honoraria from Angelini, Janssen, Otzuka, and Lundbeck. M.V. has been on the advisory board of Allergan, Almatica, Brainsway, Lundbeck, Myriad Neuroscience, Otsuka, and Purdue Pharma. He has received research support from Janssen-Ortho Inc., Purdue Pharma (Canada), the Canadian Foundation for Innovation, and Hamilton Academic Health Sciences Organization (HAHSO). E.H. has received research grants from Department of Defense, Orphan Products Division of Food and Drug Administration, Roche, and GW Pharma. He has consulted from Roche and GW Pharma and he receives editorial fees from Elsevier. J.M.M. has received research or networking funding from the Spanish official research agencies CIBERSAM-ISCIII and AGAUR, has received consultation fees from Janssen, lecture fees from AbBiotics, Exeltis, and research funding from Janssen, AbBiotics, Novartis, and Medtronic in the last 36 months. J.Z. has received grant/research support from Lundbeck, Servier, Brainsway & Pfizer, NIH, and DoD. He has received honoraria or consultation fees from Servier, Pfizer, Abbott, Lilly, Actelion, AstraZeneca, SunPharma, Roche, and Brainsway, and participated in companies sponsored by Lundbeck, Roche, Lilly, Servier, and Pfizer. J.Z. was also invited to participate as a speaker’s bureau in Abbott, SunPharma, and Brainsway. M.V. and B.B. report no financial relationships with commercial interests.

References

Fineberg, NA, Hollander, E, Pallanti, S, et al. Clinical advances in obsessive-compulsive disorder: a position statement by the International College of Obsessive-Compulsive Spectrum Disorders. Int Clin Psychopharmacol. 2020;35(4):173193. doi:10.1097/YIC.0000000000000314CrossRefGoogle ScholarPubMed
Dell’Osso, B, Benatti, B, Buoli, M, et al. The influence of age at onset and duration of illness on long-term outcome in patients with obsessive-compulsive disorder: a report from the International College of Obsessive Compulsive Spectrum Disorders (ICOCS). Eur Neuropsychopharmacol. 2013;23(8):865871. doi:10.1016/J.EURONEURO.2013.05.004CrossRefGoogle ScholarPubMed
Sheehan, D V, Lecrubier, Y, Sheehan, KH, et al. The Mini-International Neuropsychiatric Interview (M.I.N.I.): the development and validation of a structured diagnostic psychiatric interview for DSM-IV and ICD-10. J Clin Psychiatry. 1998;59(Suppl 20):2233;quiz 34–57.Google ScholarPubMed
Benatti, B, Girone, N, Celebre, L, et al. The role of gender in a large international OCD sample: a report from the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS) network. Compr Psychiatry. 2022;116:152315. doi:10.1016/J.COMPPSYCH.2022.152315CrossRefGoogle Scholar
Benatti, B, Dell’Osso, B, Shen, H, et al. Prevalence and correlates of current suicide risk in an international sample of OCD adults: a report from the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS) network and Obsessive Compulsive and Related Disorders Network (OCRN) of the European College of Neuropsychopharmacology. J Psychiatr Res. 2021;140:357363. doi:10.1016/J.JPSYCHIRES.2021.05.054CrossRefGoogle Scholar
Dell’osso, B, Vismara, M, Benatti, B, et al. 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). CNS Spectr. 2020;25(3):419425. doi:10.1017/S1092852919001068CrossRefGoogle ScholarPubMed
Dell’Osso, B, Benatti, B, Arici, C, et al. Prevalence of suicide attempt and clinical characteristics of suicide attempters with obsessive-compulsive disorder: a report from the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS). CNS Spectr. 2018;23(1):5966. doi:10.1017/S1092852917000177CrossRefGoogle ScholarPubMed
Dell’Osso, B, Benatti, B, Rodriguez, CI, et al. Obsessive-compulsive disorder in the elderly: a report from the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS). European Psychiatry. 2017;45:3640. doi:10.1016/j.eurpsy.2017.06.008CrossRefGoogle ScholarPubMed
Dell’Osso, B, Benatti, B, Hollander, E, et al. Childhood, adolescent and adult age at onset and related clinical correlates in obsessive-compulsive disorder: a report from the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS). Int J Psychiatry Clin Pract. 2016;20(4):210217. doi:10.1080/13651501.2016.1207087CrossRefGoogle ScholarPubMed
Dell’Osso, B, Nicolini, H, Lanzagorta, N, et al. Cigarette smoking in patients with obsessive compulsive disorder: a report from the International College of Obsessive Compulsive Spectrum Disorders (ICOCS). CNS Spectr. 2015;20(5):469473. doi:10.1017/S1092852915000565CrossRefGoogle ScholarPubMed
Lochner, C, Fineberg, NA, Zohar, J, et al. Comorbidity in obsessive–compulsive disorder (OCD): a report from the International College of Obsessive–Compulsive Spectrum Disorders (ICOCS). Compr Psychiatry. 2014;55(7):15131519. doi:10.1016/j.comppsych.2014.05.020CrossRefGoogle Scholar
Van Ameringen, M, Simpson, W, Patterson, B, et al. Pharmacological treatment strategies in obsessive compulsive disorder: a cross-sectional view in nine international OCD centers. J Psychopharmacol. 2014;28(6):596602. doi:10.1177/0269881113517955CrossRefGoogle ScholarPubMed
Benatti, B, Celebre, L, Girone, N, et al. Clinical characteristics and comorbidity associated with female gender in obsessive-compulsive disorder. J Psychiatr Res. 2020;131:209214. doi:10.1016/J.JPSYCHIRES.2020.09.019CrossRefGoogle ScholarPubMed
Fontenelle, LF, Mendlowicz, MV, Marques, C, et al. Early- and late-onset obsessive-compulsive disorder in adult patients: an exploratory clinical and therapeutic study. J Psychiatr Res. 2003;37(2):127133. doi:10.1016/S0022-3956(02)00087-0CrossRefGoogle ScholarPubMed
Kohn, R, Westlake, RJ, Rasmussen, SA, et al. Clinical features of obsessive-compulsive disorder in elderly patients. Am J Geriatr Psychiatry. 1997;5(3):211215. doi:10.1097/00019442-199700530-00004CrossRefGoogle ScholarPubMed
Brakoulias, V, Rehn, S. Does the severity of obsessive-compulsive symptoms reduce with age? J Affect Disord. 2017;213:178179. doi:10.1016/J.JAD.2017.02.024CrossRefGoogle ScholarPubMed
Rüther, T, Bobes, J, De Hert, M, et al. EPA guidance on tobacco dependence and strategies for smoking cessation in people with mental illness. Eur Psychiatry. 2014;29(2):6582. doi:10.1016/J.EURPSY.2013.11.002CrossRefGoogle ScholarPubMed
Abramovitch, A, Pizzagalli, DA, Geller, DA, et al. Cigarette smoking in obsessive-compulsive disorder and unaffected parents of OCD patients. Eur Psychiatry. 2015;30(1):137144. doi:10.1016/J.EURPSY.2013.12.003CrossRefGoogle ScholarPubMed
Sharma, P, Gale, TM, Fineberg, NA. Clinical correlates of tobacco smoking in OCD: a UK, case-controlled, exploratory analysis. J Behav Addict. 2012;1(4):180185. doi:10.1556/JBA.1.2012.008CrossRefGoogle ScholarPubMed
National Institute for Health and Care Excellence. Obsessive-compulsive disorder and body dysmorphic disorder: treatment. [NICE]. Published 2005. Accessed October 26, 2020. https://www.nice.org.uk/guidance/cg31.Google Scholar
Sheehan, DV. The Anxiety Disease. New York: Charles Scribners Sons; 1983.Google Scholar
Goodwin, R, Koenen, KC, Hellman, F, et al. Helpseeking and access to mental health treatment for obsessive-compulsive disorder. Acta Psychiatr Scand. 2002;106(2):143149. doi:10.1034/J.1600-0447.2002.01221.XCrossRefGoogle ScholarPubMed
Brakoulias, V, Starcevic, V, Belloch, A, et al. Comorbidity, age of onset and suicidality in obsessive–compulsive disorder (OCD): an international collaboration. Compr Psychiatry. 2017;76:7986. doi:10.1016/j.comppsych.2017.04.002CrossRefGoogle ScholarPubMed
Fontenelle, LF, Nicolini, H, Brakoulias, V. Early intervention in obsessive-compulsive disorder: from theory to practice. Compr Psychiatry. 2022;119:152353 doi:10.1016/J.COMPPSYCH.2022.152353CrossRefGoogle ScholarPubMed
Pallanti, S, Grassi, G, Sarrecchia, ED, et al. Obsessive-compulsive disorder comorbidity: clinical assessment and therapeutic implications. Front Psychiatry. 2011;2:70. doi:10.3389/FPSYT.2011.00070CrossRefGoogle ScholarPubMed
Stein, DJ, Costa, DLC, Lochner, C, et al. Obsessive-compulsive disorder. Nat Rev Dis Primers. 2019;5(1):52. doi:10.1038/S41572-019-0102-3CrossRefGoogle ScholarPubMed
Pellegrini, L, Maietti, E, Rucci, P, et al. Suicide attempts and suicidal ideation in patients with obsessive-compulsive disorder: a systematic review and meta-analysis. J Affect Disord. 2020;276:10011021. doi:10.1016/J.JAD.2020.07.115CrossRefGoogle ScholarPubMed
Albert, U, Marazziti, D, Di Salvo, G, et al. A systematic review of evidence-based treatment strategies for obsessive-compulsive disorder resistant to first-line pharmacotherapy. Curr Med Chem. 2018;25(41):56475661. doi:10.2174/0929867325666171222163645CrossRefGoogle ScholarPubMed
Fontenelle, LF, Mendlowicz, MV, Marques, C, et al. Trans-cultural aspects of obsessive-compulsive disorder: a description of a Brazilian sample and a systematic review of international clinical studies. J Psychiatr Res. 2004;38(4):403411. doi:10.1016/j.jpsychires.2003.12.004CrossRefGoogle Scholar
Nicolini, H, Salin-Pascual, R, Cabrera, B, et al. Influence of culture in obsessive-compulsive disorder and its treatment. Curr Psychiatry Rev. 2017;13(4):285. doi:10.2174/2211556007666180115105935CrossRefGoogle ScholarPubMed
Williams, MT, Chapman, LK, Simms, J V., et al. Cross‐cultural phenomenology of obsessive‐compulsive disorder. In Abramowitz, JS, Kay, D, Storch, EA (eds), The Wiley Handbook of Obsessive Compulsive Disorders. Hoboken, NJ: Wiley Blackwell; 2017, pp. 5674. doi:10.1002/9781118890233.CH4CrossRefGoogle Scholar
Petribú, K, Bastos, O. Comorbidade em trastorno obsessivo-compulsivo 3a parte: objetivos, metodologia, resultados e discussäo. J bras psiquiatr. 1997;46(8):417425.Google Scholar
Medeiros, GC, Torres, AR, Boisseau, CL, et al. A cross-cultural clinical comparison between subjects with obsessive-compulsive disorder from the United States and Brazil. Psychiatry Res. 2017;254:104111. doi:10.1016/J.PSYCHRES.2017.04.024CrossRefGoogle ScholarPubMed
Horwath, E, Weissman, MM. The epidemiology and cross-national presentation of obsessive-compulsive disorder. Psychiatr Clin North Am. 2000;23(3):493507. doi:10.1016/S0193-953X(05)70176-3CrossRefGoogle ScholarPubMed
Kirmayer, LJ, Fung, K, Rousseau, C, et al. Guidelines for training in cultural psychiatry. Can J Psychiatry. 2021;66(2):195246. doi:10.1177/0706743720907505CrossRefGoogle ScholarPubMed
Katz, JA, Rufino, KA, Werner, C, et al. OCD in ethnic minorities. Clin Exp Psychol. 2020;6(1):0106.Google Scholar
Zai, G, Barta, C, Cath, D, et al. New insights and perspectives on the genetics of obsessive-compulsive disorder. Psychiatr Genet. 2019;29(5):142151. doi:10.1097/YPG.0000000000000230CrossRefGoogle ScholarPubMed
Varinelli, A, Caricasole, V, Pellegrini, L, et al. Functional interventions as augmentation strategies for obsessive-compulsive disorder (OCD): scoping review and expert survey from the international college of obsessive-compulsive spectrum disorders (ICOCS). Int J Psychiatry Clin Pract. 2022;26(1):92107. doi:10.1080/13651501.2021.1872646CrossRefGoogle ScholarPubMed
Fineberg, NA, Van Ameringen, M, Drummond, L, et al. How to manage obsessive-compulsive disorder (OCD) under COVID-19: a clinician’s guide from the International College of Obsessive Compulsive Spectrum Disorders (ICOCS) and the Obsessive-Compulsive and Related Disorders Research Network (OCRN) of the European College of Neuropsychopharmacology. Compr Psychiatry. 2020;100:152174. doi:10.1016/j.comppsych.2020.152174CrossRefGoogle Scholar
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Table 1. Overall Results from the ICOCS Snapshot Database Studies