Lorena Fernández de la Cruz

• BSc, MSc, PhD
• Associate Professor at Karolinska Institutet

Importance Whether and under which conditions D-cycloserine (DCS) augments the effects of exposure-based cognitive behavior therapy for anxiety, obsessive-compulsive, and posttraumatic stress disorders is unclear. Objective To clarify whether DCS is superior to placebo in augmenting the effects of cognitive behavior therapy for anxiety, obsessive-...

Background Persons with neuropsychiatric disorders are at increased risk of suicide, but there is little data concerning Tourette’s and chronic tic disorders (TD/CTD). We aimed to quantify the risk of suicidal behavior in a large nationwide cohort of patients with TD/CTD, establish the contribution of psychiatric comorbidity to this risk, and ident...

The risk of death by suicide in individuals with obsessive–compulsive disorder (OCD) is largely unknown. Previous studies have been small and methodologically flawed. We analyzed data from the Swedish national registers to estimate the risk of suicide in OCD and identify the risk and protective factors associated with suicidal behavior in this grou...

Background Obsessive–compulsive disorder (OCD) has similar prevalence rates across ethnic groups. However, ethnic minorities are underrepresented in clinical trials of OCD. It is unclear whether this is also the case in clinical services. Aims To explore whether ethnic minorities with OCD are underrepresented in secondary and tertiary mental health...

In epidemiological studies, obsessive-compulsive disorder (OCD) is robustly associated with increased risk of cardiometabolic disorders, including cardiovascular diseases, type 2 diabetes, and obesity. However, the mechanisms behind these associations are unclear. We conducted genetic correlation analyses to explore shared genetic etiology and bi-d...

Trichotillomania is an understudied, underrecognized, and difficult-to-treat psychiatric disorder that affects about 1–2% of the population, predominantly women. This study aimed to characterize the sociodemographic and clinical characteristics of a Swedish cohort of individuals with a diagnosis of trichotillomania assigned in specialist services a...

Objectives: Despite the well-established association between obsessive-compulsive disorder (OCD) and several health problems, many of which are amenable to change, little is known about how OCD affects engaging in and maintaining healthy lifestyle habits and how OCD affects the experience of seeking and receiving healthcare for somatic problems. Me...

Background: Obsessive-compulsive disorder (OCD) is associated with an increased risk of morbidity and mortality due to cardiometabolic disorders. Whether this association is driven by familial factors is unknown. This population-based family study explored the familial co-aggregation of OCD and cardiometabolic disorders. Methods: We identified 6...

School-related functional impairment is common in children and adolescents with obsessive-compulsive disorder (OCD). However, little is known about the characteristics of youth with OCD who struggle in school, whether these struggles interfere with treatment outcomes, and whether treatment improves school-related function. Among 385 youth with OCD...

Background: Obsessive-compulsive disorder (OCD) is associated with an increased risk of cardiometabolic disorders. We developed a lifestyle intervention, named LIFT, aimed at improving lifestyle habits and reducing cardiometabolic risk factors in individuals with OCD. Aims: 1) To establish the feasibility and acceptability of LIFT; 2) to evaluate i...

Background Tourette syndrome (TS) and chronic tic disorder (CTD) may be associated with an increased risk of mortality, but specific causes of death are poorly understood. Objectives In this matched cohort and sibling cohort study, we estimated the risk of all‐cause and cause‐specific mortality in individuals with TS/CTD, compared with unaffected...

Background: Severe disruptions in mental healthcare services were reported during the COVID-19 pandemic. However, little data are available on whether services were able to maintain treatment efficacy during this period.Objective: The aims of this study were to 1) compare outpatient mental healthcare treatment effects before and during the COVID-19...

Background A large proportion of individuals experience functional impairment in everyday life due to climate worry. However, the current understanding of this functional impairment is limited by the use of suboptimal measures. Furthermore, it is not known whether functional impairment due to climate worry affects pro-environmental behaviors (PEBs)...

Body dysmorphic disorder (BDD) is an obsessive-compulsive disorder-related psychiatric condition characterized by an intense preoccupation with perceived physical flaws that are not observable by others. BDD affects ~2% of the adult population but is underdiagnosed, partly owing to limited clinician awareness, and undertreated, partly due to limite...

Background: Despite considerable interest in the consequences of benzodiazepine and benzodiazepine-related Z-drug (BZDR) use, little is known about whether and how initiation of BZDR treatment contributes to the development of alcohol- and drug-related problems. Aim: To examine the association of incident BZDR dispensing with subsequent development...

The extent to which bullying victimization is associated with an increased risk of obsessive-compulsive disorder (OCD) has received little empirical attention. This longitudinal, population-based, genetically informative study examined whether self-reported bullying victimization at age 15 was associated with a clinical diagnosis of OCD in the Swed...

INTRODUCTION: The risk of suicide is substantially elevated in psychiatric inpatients. However, little is known about the risk of suicide among those treated against their own will as involuntary psychiatric care patients (IPC). Leveraging data from multiple linked nationwide registries, this descriptive study reports different facets of suicide am...

Objective: To evaluate the feasibility, acceptability, safety, preliminary efficacy, and preliminary maintenance of TICNET, an online therapist-guided exposure and response prevention (ERP) for adults with Tourette syndrome or chronic tic disorder (TS/CTD).Design: Single-group, unmasked feasibility trial.Setting: A psychiatric outpatient clinic spe...

Body dysmorphic disorder (BDD) is a relatively common and highly impairing mental disorder that is strikingly underdiagnosed and undertreated in Child and Adolescent Mental Health Services (CAMHS). The only clinical guidelines for the management of BDD in youth were published nearly 20 years ago, when empirical knowledge was sparse. Fortunately, th...

Importance Behavior therapy is a recommended intervention for Tourette syndrome (TS) and chronic tic disorder (CTD), but availability is limited and long-term effects are uncertain. Objective To investigate the long-term efficacy and cost-effectiveness of therapist-supported, internet-delivered exposure and response prevention (ERP) vs psychoeduca...

This cohort study estimates the heritability of clinically diagnosed obsessive-compulsive disorder in a sample of twins.

Background Obsessive-compulsive disorder (OCD) has been associated with a broad range of health-related issues. Unhealthy lifestyle habits such as physical inactivity, an unhealthy diet, smoking, and alcohol consumption are hypothesized to contribute to this association. However, the lifestyle habits of individuals with OCD have been scarcely inves...

Objective To estimate the risk of all cause and cause specific mortality in people with obsessive-compulsive disorder (OCD) compared with matched unaffected people from the general population and with their unaffected siblings. Design Population based matched cohort and sibling cohort study. Setting Register linkage in Sweden. Participants Popul...

The Appearance Anxiety Inventory (AAI) is a self-report measure assessing the typical cognitions and behaviours of body dysmorphic disorder (BDD). Despite its use in research and clinical settings, its psychometric properties have not been evaluated in young people with BDD. We examined the factor structure, reliability, validity, and sensitivity t...

Background We aimed to investigate the associations of pre-existing maternal cardiovascular disease (CVD) with attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD) and intellectual disability (ID) in offspring. Methods This population-based cohort study included singletons live-born without major malformations in Sweden...

Importance Hypochondriasis, also known as health anxiety disorder, is a prevalent, yet underdiagnosed psychiatric disorder characterized by persistent preoccupation about having serious and progressive physical disorders. The risk of mortality among individuals with hypochondriasis is unknown. Objective To investigate all-cause and cause-specific...

Body dysmorphic disorder (BDD) is a prevalent and impairing psychiatric condition that typically debuts in adolescence and is associated with risky behaviours. The disorder can be effectively treated with cognitive behaviour therapy (CBT). However, CBT for BDD is seldom available primarily due to a shortage of trained therapists. Internet-delivered...

Purpose Depression and anxiety afflict millions worldwide causing considerable disability. MULTI-PSYCH is a longitudinal cohort of genotyped and phenotyped individuals with depression or anxiety disorders who have undergone highly structured internet-based cognitive-behaviour therapy (ICBT). The overarching purpose of MULTI-PSYCH is to improve risk...

Background: Cognitive behavioral therapy (CBT) is a moderately efficacious treatment for hoarding disorder (HD), with most individuals remaining symptomatic after treatment. The Joining Forces Trial will evaluate whether 10 weeks of in-home decluttering can significantly augment the outcomes of group CBT. Methods: A randomized controlled trial o...

Background Obsessive-compulsive disorder (OCD) has been associated with a broad range of health-related issues. Unhealthy lifestyle habits such as physical inactivity, an unhealthy diet, smoking, and alcohol consumption are hypothesized to contribute to this association. However, the lifestyle habits of individuals with OCD have been scarcely inves...

Background The causes of obsessive-compulsive disorder (OCD) remain unknown. Gene-searching efforts are well underway, but the identification of environmental risk factors is at least as important and should be a priority because some of them may be amenable to prevention or early intervention strategies. Genetically informative studies, particular...

Importance: Obsessive-compulsive disorder (OCD) is associated with adverse health-related outcomes. However, pregnancy and neonatal outcomes among women with OCD have been sparsely studied. Objective: To evaluate associations of maternal OCD with pregnancy, delivery, and neonatal outcomes. Design, setting, and participants: Two register-based...

Background: Many children with tic disorders outgrow their tics, but little is known about the proportion of individuals who will continue to require specialist services in adulthood and which variables are associated with tic persistence. Objectives: The aims were to estimate the proportion of individuals first diagnosed with tic disorders in c...

Background Cognitive behavioral therapy (CBT) is a moderately efficacious treatment for hoarding disorder (HD), with most individuals remaining symptomatic after treatment. The Joining Forces trial will evaluate whether 10 weeks of in-home decluttering can significantly augment the outcomes of group CBT. Methods A randomized controlled trial of in...

Background The causes of obsessive-compulsive disorder (OCD) remain unknown. Gene-searching efforts are well underway, but the identification of environmental risk factors is at least as important and should be a priority because some of them may be amenable to prevention or early intervention strategies. Genetically informative studies, particular...

Background: Depression and anxiety are risk factors for patients with myocardial infarction (MI). However, the association of a previous psychiatric diagnosis of anxiety or depression, or only such self-reported symptoms, with cardiovascular outcomes and mortality post-MI has not been previously examined in the same nationwide cohort. Methods: W...

Importance: Maternal immune activation (MIA) leading to altered neurodevelopment in utero is a hypothesized risk factor for psychiatric outcomes in offspring. Primary antibody immunodeficiencies (PIDs) constitute a unique natural experiment to test the MIA hypothesis of mental disorders. Objective: To assess the association of maternal and pater...

Background: Maternal heart disease is associated with impaired placentation and adverse neonatal outcomes, but whether it increases the risk of neurodevelopmental disorders in offspring remains unknown. This study aimed to determine the association between pre-existing maternal cardiovascular disease (CVD) and the risk of attention-deficit/hyperact...

Background: Previous research has shown a marked increase in the levels of worry related to climate change in the population and has described that some individuals experience significant impairment in everyday life functioning due to this worry. The aim of the current study was to extend those findings using gold standard measures of worry and imp...

Introduction: The operational definitions of treatment response, partial response, and remission in obsessive-compulsive disorder (OCD) are widely used in clinical trials and regular practice. However, the clinimetric sensitivity of these definitions, that is, whether they identify patients that experience meaningful changes in their everyday life...

Purpose Individuals with obsessive–compulsive disorder (OCD) often report driving-related obsessions, such as fears of causing accidents, but the risk of transport accidents in OCD is unknown. We investigated whether individuals with OCD have an increased risk of serious transport accidents and convictions due to traffic offenses and explored the r...

Objective Maternal exposure to cardiovascular disease (CVD) is associated with adverse maternal and neonatal health outcomes. However, its association with offspring’s long-term neurodevelopmental disorders (NDDs) is not yet known. We aimed to investigate the association between maternal pre-existing CVDs and children’s NDDs. ApproachThis nationwid...

Importance: The availability of behavior therapy for individuals with Tourette syndrome (TS) and chronic tic disorder (CTD) is limited. Objective: To determine the efficacy and cost-effectiveness of internet-delivered exposure and response prevention (ERP) for children and adolescents with TS or CTD. Design, setting, and participants: This sin...

In clinical trials of obsessive-compulsive disorder (OCD), clinical outcomes are generally measured using lengthy clinician-administered interviews. However, in routine clinical practice, many clinicians lack the time to administer such instruments. This study evaluated cut-offs for treatment response and remission in OCD using the self-rated Obses...

Background Post-infectious autoimmune processes are hypothesized to be causally related to both obsessive-compulsive disorder (OCD) and tic disorders, but current evidence is conflicting. This study examined whether prenatal maternal (and paternal, as an internal control) infections and early childhood infections in the offspring (i.e., during the...

Individuals with obsessive-compulsive disorder (OCD) more often think about, attempt, and die by suicide than individuals from the general population. Sexual and religious obsessions (i.e., taboo obsessions) have been linked to increased risk of suicidality, but it is unclear if they explain additional risk over and above other risk factors. We ref...

The Yale-Brown Obsessive-Compulsive Scale Modified for Body Dysmorphic Disorder for Adolescents (BDD-YBOCS-A) is a clinician-rated measure of BDD symptom severity in youth. Despite widespread use in both research and clinical practice, its psychometric properties have not been formally evaluated. The current study examined the factor structure, rel...

Importance: Neurobiological models have postulated shared neural mechanisms between obsessive-compulsive disorder (OCD) and substance use disorders, but results from clinical and epidemiological studies are conflicting or even suggest that OCD may be protective against substance misuse. Objective: To investigate whether OCD and obsessive-compuls...

Body dysmorphic disorder (BDD) typically originates in adolescence and is associated with considerable adversity. Evidence-based treatments exist but research on clinical outcomes in naturalistic settings is extremely scarce. We evaluated the short- and long-term outcomes of a large cohort of adolescents with BDD receiving specialist multimodal tre...

Tourette syndrome (TS) is now recognized as a common neurodevelopmental disorder affecting children and adults. It has gained increasingly public awareness and scientific interest worldwide. Knowledge of its clinical presentation and available treatment approaches has increased dramatically over the last two decades. Tourette Syndrome offers a uniq...

In clinical trials of obsessive-compulsive disorder (OCD), clinical outcomes are generally measured using lengthy clinician-administered interviews. However, in routine clinical practice, many clinicians lack the time to administer such instruments. This study evaluated cut-offs for treatment response and remission in OCD using the self-rated Obses...

Importance: Tic disorders are associated with multiple social adversities, but little is known about the experience of violent assault (including sexual assault) and criminality in this group. Objective: To establish if Tourette syndrome (TS) and chronic tic disorder (CTD) are associated with an increased risk of experiencing violent assault and...

Little is known about the contribution of pregnancy-related parental and perinatal factors to the development of stress-related disorders. We aimed to investigate whether parental/perinatal adversities entail higher risks of stress-related disorders in the offspring, later in life, by accounting for genetic and early environmental factors. Based on...

Current knowledge on the general somatic health of individuals with obsessive-compulsive disorder (OCD) is very limited. Here, we critically review the emerging literature on the topic. Rapidly accumulating evidence indicates an association between OCD and autoimmune diseases, which is not limited to streptococcus-related conditions. Similarly, an...

BACKGROUND: Depression and anxiety are known risk factors for patients with myocardial infarction (MI). However, the association of a previous psychiatric diagnosis of depression or anxiety, or such self-reported symptoms, with cardiovascular outcomes and mortality post MI has not previously been examined in the same nationwide cohort. METHODS: Us...

Body dysmorphic disorder (BDD) often starts in childhood, with most cases developing symptoms before age 18. Yet, BDD research has primarily focused on adults. We report the clinical characteristics of the world's largest cohort of carefully diagnosed youths with BDD and focus on previously unexplored sex and age differences. We systematically coll...

Background Cesarean delivery (CD) has been associated with postpartum psychiatric disorders, but less is known about the risk of suicidal behaviors. We estimated the incidence and risk of suicide attempts and deaths during the first postpartum year in mothers who delivered via CD v. vaginally. Method All deliveries in Sweden between 1973 and 2012...

Objectives In the International Classification of Diseases, Tenth Edition (ICD-10), hypochondriasis (illness anxiety disorder) and dysmorphophobia (body dysmorphic disorder) share the same diagnostic code (F45.2). However, the Swedish ICD-10 allows for these disorders to be coded separately (F45.2 and F45.2A, respectively), potentially offering uni...

Obsessive-compulsive disorder (OCD) and autism spectrum disorder (ASD) frequently co-occur. Standard cognitive behaviour therapy (CBT) for OCD outcomes are poorer in young people with ASD, compared to those without. The aim of this naturalistic study was to evaluate the effectiveness of a novel adolescent autism-adapted CBT manual for OCD in a spec...

Background: Insomnia is common in Tourette syndrome (TS) and chronic tic disorder (CTD), but precise prevalence estimates are lacking. Objective: In this Swedish register-based cohort study, we estimated the prevalence of insomnia in TS/CTD and quantified the magnitude of this association, accounting for familial confounders and relevant somatic...

Background Treatment guidelines recommend behaviour therapy (BT) for patients with Tourette syndrome (TS) and chronic tic disorder (CTD). However, BT is rarely accessible due to limited availability of trained therapists and long travel distances to specialist clinics. Internet-delivered BT has the potential of overcoming these barriers through rem...

Background: Treatment guidelines recommend behaviour therapy (BT) for patients with Tourette syndrome (TS) and chronic tic disorder (CTD). However, BT is rarely accessible due to limited availability of trained therapists and long travel distances to specialist clinics. Internet-delivered BT has the potential of overcoming these barriers through re...

Importance Severe forms of Tourette syndrome or chronic tic disorder (TS/CTD) may involve repeated head jerking. Isolated case reports have described a spectrum of severe neck disorders in individuals with TS/CTD. However, the nature and prevalence of cervical spine disorders in TS/CTD are unknown. Objective To establish if TS/CTD are associated w...

It is unclear if the results of randomised controlled trials (RCTs) of behaviour therapy (BT) for Tourette syndrome (TS) and chronic tic disorder (CTD) can be generalised to naturalistic clinical settings and are durable long-term. In this naturalistic study, 74 young people with TS/CTD received BT at a specialist clinic. Data were collected at bas...

In the latest edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), obsessive-compulsive disorder (OCD) included a new “tic-related” specifier. However, strong evidence supporting tic-related OCD as a distinct subtype of OCD is lacking. This study investigated whether, at the population level, tic-related OCD has a stronger...

Obsessive−compulsive disorder (OCD) is associated with high risk of suicide. It is yet unknown whether OCD and suicidal behaviors coaggregate in families and, if so, what are the mechanisms underlying this coaggregation. In a population-based birth cohort and family study, we linked individuals born in Sweden in 1967-2003 (n = 3,594,181) to their p...

Importance: Recent studies suggest that cesarean delivery (CD) is associated with increased risk of neurodevelopmental disorders in children, although they were unable to control for indications for CD or familial confounding beyond full siblings. Objective: To examine the association between CD and neurodevelopmental and psychiatric disorders i...

Background Little is known about the lived experiences of individuals with tic disorders when driving vehicles or trying to obtain a driving license. Objective To survey the driving‐related experiences of adults with tic disorders. Methods A global survey was disseminated via social media, international patient organizations, and experts between...

Importance Posttraumatic stress disorder (PTSD) has been associated with impaired educational performance. Previous studies on the disorder could not control for important measured and unmeasured confounders. Objective To prospectively investigate the association between PTSD and objective indicators of educational attainment across the life span,...

Current knowledge on the general somatic health and causes of death in Tourette syndrome and chronic tic disorder is very limited. Here, we review the available literature on the topic, while highlighting strengths and weaknesses of the studies conducted to date. These previous works have suggested associations between Tourette syndrome and chronic...

Individuals with obsessive-compulsive disorder (OCD) may have an increased risk of cardiovascular disease (CVD), but evidence for specific types of CVD is limited. This population-based, sibling-controlled cohort study investigated the risk of specific CVD in individuals with OCD. Linking data from various Swedish population-based registers, we exp...

Background : Obsessive-compulsive disorder (OCD) has been linked with elevated risk of suicidality. However, most previous studies have been cross-sectional, and little is known about the aetiology of the association between obsessive-compulsive symptoms (OCS) and suicidality in young adults. Methods : Participants were members of the Child and Ad...

Determining response or remission status in body dysmorphic disorder (BDD) usually requires a lengthy interview with a trained clinician. This study sought to establish empirically derived cut-offs to define treatment response and remission in BDD using a brief self-reported instrument, the Appearance Anxiety Inventory (AAI). Results from three cli...

Background: It is unknown whether individuals with tic disorders are at increased risk for serious transport accidents. Objectives: The aim of this study was to investigate the risk for injuries or death caused by transport and motor vehicle accidents in individuals with Tourette syndrome or chronic tic disorder. Methods: This population-based...

Background: Previous research indicates that body dysmorphic disorder (BDD) is associated with risk of suicidality. However, studies have relied on small and/or specialist samples and largely focussed on adults, despite these difficulties commonly emerging in youth. Furthermore, the aetiology of the relationship remains unknown. Methods: Two ind...

Background: Psychiatric comorbidities are common and major determinants of quality of life in idiopathic dystonia. Their prevalence estimates from service-based studies are heterogeneous. Objective: We explored the association between idiopathic dystonia and depressive disorders, anxiety disorders, suicide attempts, and death by suicide using Sw...

Pediatric body dysmorphic disorder (BDD) is challenging to treat. This study aimed to establish the prevalence of insomnia in youth with BDD and explore its impact on clinical outcomes. Sixty-six children and adolescents with BDD consecutively referred to a specialist clinic completed a range of clinical measures, including the Yale-Brown Obsessive...

Background It remains unclear if individuals with Tourette syndrome (TS) or chronic tic disorder (CTD) have an elevated risk of subsequent substance misuse. Methods In this population-based cohort study, we investigated the association between ICD diagnoses of TS/CTD and substance misuse outcomes, accounting for psychiatric comorbidity and familia...

Background: Treatment guidelines recommend behaviour therapy (BT) as the first-line intervention for patients with Tourette syndrome (TS) and chronic tic disorder (CTD). The efficacy of BT has been documented in randomised controlled trials (RCTs), but it is unclear to what extent these results are generalisable to real-world clinical settings, and...

Importance The hypothesis that disrupted immune function is implicated in the pathophysiology of psychiatric disorders and suicide is gaining traction, but the underlying mechanisms are largely unknown. Primary humoral immunodeficiencies (PIDs) are rare deficiencies of the immune system—mainly dysfunction of antibody production—and are associated w...

Background: Population-based administrative registers are often used for research purposes. However, their potential usefulness depends on the validity of the registered information. This study assessed the validity of the recorded codes for social anxiety disorder (SAD), also known as social phobia, in the Swedish National Patient Register (NPR)....

A global survey of the perceived impact of the COVID-19 outbreak on the severity of tics in persons with Tourette syndrome (TS) or chronic tic disorder (CTD).

Hoarding disorder (HD) is a mental disorder that was newly included in the obsessive–compulsive and related disorders chapter of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). It is also planned for inclusion in the International Classification of Diseases, eleventh revision (ICD-11). Individuals meeting the...