Exposure to life stress is known to adversely impact the course of bipolar disorder. Few studies have disentangled the effects of multiple types of stressors on the longitudinal course of bipolar I disorder. This study examines whether severity of chronic stressors and exposure to trauma are prospectively associated with course of illness among bipolar patients.

One hundred and thirty-one participants diagnosed with bipolar I disorder were recruited through treatment centers, support groups and community advertisements. Severity of chronic stressors and exposure to trauma were assessed at study entry with in-person interviews using the Bedford College Life Event and Difficulty Schedule (LEDS). Course of illness was assessed by monthly interviews conducted over the course of 24 months (over 3000 assessments).

Trauma exposure was related to more severe interpersonal chronic stressors. Multiple regression models provided evidence that severity of overall chronic stressors predicted depressive but not manic symptoms, accounting for 7.5% of explained variance.

Overall chronic stressors seem to be an important determinant of depressive symptoms within bipolar disorder, highlighting the importance of studying multiple forms of life stress.

High occupational suicide rates are often linked to easy occupational access to a method of suicide. This study aimed to compare suicide rates across all occupations in Britain, how they have changed over the past 30 years, and how they may vary by occupational socio-economic group.

We used national occupational mortality statistics, census-based occupational populations and death inquiry files (for the years 1979–1980, 1982–1983 and 2001–2005). The main outcome measures were suicide rates per 100 000 population, percentage changes over time in suicide rates, standardized mortality ratios (SMRs) and proportional mortality ratios (PMRs).

Several occupations with the highest suicide rates (per 100 000 population) during 1979–1980 and 1982–1983, including veterinarians (ranked first), pharmacists (fourth), dentists (sixth), doctors (tenth) and farmers (thirteenth), have easy occupational access to a method of suicide (pharmaceuticals or guns). By 2001–2005, there had been large significant reductions in suicide rates for each of these occupations, so that none ranked in the top 30 occupations. Occupations with significant increases over time in suicide rates were all manual occupations whereas occupations with suicide rates that decreased were mainly professional or non-manual. Variation in suicide rates that was explained by socio-economic group almost doubled over time from 11.4% in 1979–1980 and 1982–1983 to 20.7% in 2001–2005.

Socio-economic forces now seem to be a major determinant of high occupational suicide rates in Britain. As the increases in suicide rates among manual occupations occurred during a period of economic prosperity, carefully targeted suicide prevention initiatives could be beneficial.

Neuroticism has been consistently correlated with the post-traumatic stress disorder (PTSD) response to traumatic events. Interpretation of these findings is limited by the retrospective nature of these findings: neuroticism was measured after the trauma had occurred. The prospective association of neuroticism with PTSD has not been examined (the relationship of neuroticism with PTSD symptoms was examined in a few prospective studies). We evaluate prospectively the relationship of neuroticism, measured at baseline, with the cumulative occurrence of PTSD during the subsequent 10 years, using data from a longitudinal epidemiological study of young adults.

A sample of 1007 young adults randomly selected from the membership of a large health maintenance organization in southeast Michigan was assessed at baseline and followed up at 3, 5 and 10 years later. We conducted a series of multinomial logistic regressions to estimate the relative risk (RR) of exposure to trauma and PTSD by neuroticism at baseline, adjusting for history of major depression (n = 990).

During the 10-year follow-up, 50.2% of the sample experienced traumatic events and 5.2% developed PTSD. Neuroticism score at baseline increased significantly the RR of PTSD response to trauma. Additional analysis revealed that, among persons with history of major depression at baseline, RR for PTSD associated with neuroticism was equal to the null value of 1, but was increased significantly among those with no history of major depression.

The results confirm the role of neuroticism as diathesis in the PTSD response to traumatic experiences.

Moodscope is an entirely service-user-developed online mood-tracking and feedback tool with built-in social support, designed to stabilize and improve mood. Many free internet tools are available with no assessment of acceptability, validity or usefulness. This study provides an exemplar for future assessments.

A mixed-methods approach was used. Participants with mild to moderate low mood used the tool for 3 months. Correlations between weekly assessments using the Patient Health Questionnaire (PHQ-9) and the Generalized Anxiety Disorder Assessment (GAD-7) with daily Moodscope scores were examined to provide validity data. After 3 months, focus groups and questionnaires assessed use and usability of the tool.

Moodscope scores were correlated significantly with scores on the PHQ-9 and the GAD-7 for all weeks, suggesting a valid measure of mood. Low rates of use, particularly toward the end of the trial, demonstrate potential problems relating to ongoing motivation. Questionnaire data indicated that the tool was easy to learn and use, but there were concerns about the mood adjectives, site layout and the buddy system. Participants in the focus groups found the tool acceptable overall, but felt clarification of the role and target group was required.

With appropriate adjustments, Moodscope could be a useful tool for clinicians as a way of initially identifying patterns and influences on mood in individuals experiencing low mood. For those who benefit from ongoing mood tracking and the social support provided by the buddy system, Moodscope could be an ongoing adjunct to therapy.

Medical patients are often screened for distress in the clinic using a questionnaire such as the Hospital Anxiety and Depression Scale (HADS) while awaiting their consultation. However, might the context of the clinic artificially inflate the distress score? To address this question we aimed to determine whether those who scored high on the HADS in the clinic remained high scorers when reassessed later at home.

We analysed data collected by a distress and depression screening service for cancer out-patients. All patients had completed the HADS in the clinic (on computer or on paper) prior to their consultation. For a period, patients with a high score (total of ⩾15) also completed the HADS again at home (over the telephone) 1 week later. We used these data to determine what proportion remained high scorers and the mean change in their scores. We estimated the effect of ‘regression to the mean’ on the observed change.

Of the 218 high scorers in the clinic, most [158 (72.5%), 95% confidence interval (CI) 66.6–78.4] scored high at reassessment. The mean fall in the HADS total score was 1.74 (95% CI 1.09–2.39), much of which could be attributed to the estimated change over time (regression to the mean) rather than the context.

Pre-consultation distress screening in clinic is widely used. Reassuringly, it only modestly overestimates distress measured later at home and consequently would result in a small proportion of unnecessary further assessments. We conclude it is a reasonable and convenient strategy.

Persons developing schizophrenia (SCZ) manifest various pre-morbid neuropsychological deficits, studied most often by measures of IQ. Far less is known about pre-morbid neuropsychological functioning in individuals who later develop bipolar psychoses (BP). We evaluated the specificity and impact of family history (FH) of psychosis on pre-morbid neuropsychological functioning.

We conducted a nested case-control study investigating the associations of neuropsychological data collected systematically at age 7 years for 99 adults with psychotic diagnoses (including 45 SCZ and 35 BP) and 101 controls, drawn from the New England cohort of the Collaborative Perinatal Project (CPP). A mixed-model approach evaluated full-scale IQ, four neuropsychological factors derived from principal components analysis (PCA), and the profile of 10 intelligence and achievement tests, controlling for maternal education, race and intra-familial correlation. We used a deviant responder approach (<10th percentile) to calculate rates of impairment.

There was a significant linear trend, with the SCZ group performing worst. The profile of childhood deficits for persons with SCZ did not differ significantly from BP. Neuropsychological impairment was identified in 42.2% of SCZ, 22.9% of BP and 7% of controls. The presence of psychosis in first-degree relatives (FH+) significantly increased the severity of childhood impairment for SCZ but not for BP.

Pre-morbid neuropsychological deficits are found in a substantial proportion of children who later develop SCZ, especially in the SCZ FH+ subgroup, but less so in BP, suggesting especially impaired neurodevelopment underlying cognition in pre-SCZ children. Future work should assess genetic and environmental factors that explain this FH effect.

Although depression and mania are often assumed to be polar opposites, studies have shown that, in patients with bipolar disorder, they are weakly positively correlated and vary somewhat independently over time. Thus, when investigating relationships between specific psychological processes and specific symptoms (mania and depression), co-morbidity between the symptoms and changes over time must be taken into account.

A total of 253 bipolar disorder patients were assessed every 24 weeks for 18 months using the Hamilton Rating Scale for Depression (HAMD), the Bech–Rafaelsen Mania Assessment Scale (MAS), the Rosenberg Self-Esteem Questionnaire (RSEQ), the Dysfunctional Attitudes Scale (DAS), the Internal, Personal and Situational Attributions Questionnaire (IPSAQ) and the Personal Qualities Questionnaire (PQQ). We calculated multilevel models using the xtreg module of Stata 9.1, with psychological and clinical measures nested within each participant.

Mania and depression were weakly, yet significantly, associated; each was related to distinct psychological processes. Cross-sectionally, self-esteem showed the most robust associations with depression and mania: depression was associated with low positive and high negative self-esteem, and mania with high positive self-esteem. Depression was significantly associated with most of the other self-referential measures, whereas mania was weakly associated only with the externalizing bias of the IPSAQ and the achievement scale of the DAS. Prospectively, low self-esteem predicted future depression.

The associations between different self-referential thinking processes and different phases of bipolar disorder, and the presence of the negative self-concept in both depression and mania, have implications for therapeutic management, and also for future directions of research.

Individuals at ultra-high risk (UHR) for psychosis show reduced neurocognitive performance across domains but it is unclear which reductions are associated with transition to frank psychosis. The aim of this study was to investigate differences in baseline neurocognitive performance between UHR participants with (UHR-P) and without transition to psychosis (UHR-NP) and a healthy control (HC) group and examine neurocognitive predictors of transition over the medium to long term.

A sample of 325 UHR participants recruited consecutively from the Personal Assessment and Crisis Evaluation (PACE) Clinic in Melbourne and 66 HCs completed a neurocognitive assessment at baseline. The UHR group was followed up between 2.39 and 14.86 (median = 6.45) years later. Cox regression was used to investigate candidate neurocognitive predictors of psychosis onset.

The UHR group performed more poorly than the HC group across a range of neurocognitive domains but only performance on digit symbol coding and picture completion differed between the groups. The risk of transition was only significantly associated with poorer performance on visual reproduction [hazard ratio (HR) 0.919, 95% confidence interval (CI) 0.876–0.965, p = 0.001] and matrix reasoning (HR 0.938, 95% CI 0.883–0.996, p = 0.037). These remained significant even after controlling for psychopathology at baseline.

This study is the longest follow-up of an UHR sample to date. UHR status was associated with poorer neurocognitive performance compared to HCs on some tasks. Cognition at identification as UHR was not a strong predictor of risk for transition to psychosis. The results suggests the need to include more experimental paradigms that isolate discrete cognitive processes to better understand neurocognition at this early stage of illness.

Assortative mating has been demonstrated in mental disorders but the extent of cohabitation between patients with clinically diagnosed psychiatric disease has been poorly explored.

We conducted a register-based study of all Danes between 18 and 70 years of age in a 13-year observational period, linking data on individuals' contacts with psychiatric services with data on individuals' cohabitation status. Two different Poisson regression analyses were performed: the first comparing the rates of commencing cohabitation with a psychiatric patient between individuals, depending on whether the individuals themselves had, or did not have, a psychiatric diagnosis; the second comparing the incidence rates of psychiatric diagnoses for individuals cohabitating with psychiatric patients with the similar rates for individuals living with unaffected cohabitants.

In total, 159 929 (5.0%) out of 3 204 633 individuals were given a psychiatric diagnosis during the study period. Diagnosed individuals had an overall rate ratio (RR) of commencing cohabitation with a psychiatric patient of 1.95 [95% confidence interval (CI) 1.90–2.00] for women and 1.65 (95% CI 1.61–1.69) for men, when compared with unaffected individuals. The overall RR of receiving a psychiatric diagnosis while cohabitating with a psychiatric patient was 2.40 (95% CI 2.31–2.49) for women and 2.91 (95% CI 2.81–3.01) for men, when compared with those cohabitating with unaffected individuals. Individuals with schizophrenia and men with bipolar disorder had the highest RR of commencing cohabitation with a cohabitant with a similar diagnosis.

Cohabitation among individuals with severe psychiatric disorders is increased. This has implications for research and for the clinical management of patients.

Individual variation in the clinical course of bipolar disorder may have prognostic and therapeutic implications but is poorly reflected in current classifications. We aimed to establish a typology of the individual clinical trajectories based on detailed prospective medium-term follow-up.

Latent class analysis (LCA) of nine characteristics of clinical course (time depressed, severity of depression, stability of depression, time manic, severity of mania, stability of mania, mixed symptoms, mania-to-depression and depression-to-mania phase switching) derived from life charts prospectively tracking the onsets and offsets of (hypo)manic, depressive, mixed and subsyndromal episodes in a representative sample of 176 patients with bipolar disorder.

The best-fitting model separated patients with bipolar disorder into large classes of episodic bipolar (47%) and depressive type (32%), moderately sized classes characterized by prolonged hypomanias (10%) and mixed episodes (5%) and five small classes with unusual course characteristics including mania-to-depression and depression-to-mania transitions and chronic mixed affective symptoms. This empirical typology is relatively independent of the distinction between bipolar disorder type I and type II. Lifetime co-morbidity of alcohol use disorders is characteristic of the episodic bipolar course type.

There is potential for a new typology of clinical course based on medium-term naturalistic follow-up of a representative clinical sample of patients with bipolar disorder. Predictive validity and stability over longer follow-up periods remain to be established.

Little is known about suicide risk among offspring of parents hospitalized for schizophrenia and the mechanisms behind this association.

We applied a nested case–control design based on linkage of Swedish population-based registers. Among 12- to 30-year-old offspring, we identified 68 318 offspring with suicidal behavior (attempted and completed suicide) and their parents. Five healthy control–parent pairs were matched to each suicidal case–parent pair and conditional logistic regression used to obtain odds ratios (ORs). Further, to disentangle familial confounding from causal environmental mechanisms, we compared the population-based suicide risk with the risk found within full-cousins and half-cousins differentially exposed to parental schizophrenia.

Offspring of parents with schizophrenia had significantly increased suicide risk after accounting for socio-economic status, parental suicidal behavior and offspring mental illness [OR 1.68, 95% confidence interval (CI) 1.53–1.85]. Suicide risks in offspring of schizophrenic mothers and fathers were similar in magnitude; so were risks across different developmental periods. Importantly, offspring suicide risk remained essentially unchanged across genetically different relationships; offspring of siblings discordant for schizophrenia had equivalent risk increases within full-cousins (OR 1.96, 95% CI 1.66–2.31) and half-cousins (OR 1.69, 95% CI 1.17–2.44).

Parental schizophrenia was associated with increased risk of offspring suicidal behavior, independent of gender of the schizophrenic parent, and persisting into adulthood. The suicide risk in offspring remained at a similar level when comparing genetically different relationships, which suggests that at least part of the association is due to environmental mechanisms. These findings should inspire increased attention to suicidal ideation and prevention efforts in offspring of parents with schizophrenia.

Guidelines and mental healthcare models suggest the use of psychological treatment for anxiety disorders in primary care but systematic estimates of the effect sizes in primary care settings are lacking. The aim of this study was to examine the effectiveness of psychological therapies in primary care for anxiety disorders.

The Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE, Medline, PsycINFO and Pubmed databases were searched in July 2010. Manuscripts describing psychological treatment for anxiety disorders/increased level of anxiety symptoms in primary care were included if the research design was a randomized controlled trial (RCT) and if the psychological treatment was compared with a control group.

In total, 1343 abstracts were identified. Of these, 12 manuscripts described an RCT comparing psychological treatment for anxiety with a control group in primary care. The pooled standardized effect size (12 comparisons) for reduced symptoms of anxiety at post-intervention was d = 0.57 [95% confidence interval (CI) 0.29–0.84, p = 0.00, the number needed to treat (NNT) = 3.18]. Heterogeneity was significant among the studies (I2 = 58.55, Q = 26.54, p < 0.01). The quality of studies was not optimal and missing aspects are summarized.

We found a moderate effect size for the psychological treatment of anxiety disorders in primary care. Several aspects of the treatment are related to effect size. More studies are needed to evaluate the long-term effects given the chronicity and recurrent nature of anxiety.

While bipolar disorder (BD) is a leading cause of disability, and an important contributor to disability in BD is cognitive impairment, there is little systematic research on the longitudinal course of cognitive function and instrumental activities of daily living (IADLs) in late-life. In this report, we characterize the 2-year course of cognitive function and IADLs in older adults with BD.

We recruited non-demented individuals 50 years and older with BD I or BD II (n = 47) from out-patient clinics or treatment studies at the University of Pittsburgh. Comparator subjects (‘controls’) were 22 individuals of comparable age and education with no psychiatric or neurologic history, but similar levels of cardiovascular disease. We assessed cognitive function and IADLs at baseline, 1- and 2-year time-points. The neuropsychological evaluation comprised 21 well-established and validated tests assessing multiple cognitive domains. We assessed IADLs using a criterion-referenced, performance-based instrument. We employed repeated-measures mixed-effects linear models to examine trajectory of cognitive function. We employed non-parametric tests for analysis of IADLs.

The BD group displayed worse cognitive function in all domains and worse IADL performance than the comparator group at baseline and over follow-up. Global cognitive function and IADLs were correlated at all time-points. The BD group did not exhibit accelerated cognitive decline over 2 years.

Over 2 years, cognitive impairment and associated functional disability of older adults with BD appear to be due to long-standing neuroprogressive processes compounded by normal cognitive aging rather than accelerated cognitive loss in old age.

Psychotic disorders are highly heritable such that the unaffected relatives of patients may manifest characteristics, or endophenotypes, that are more closely related to risk genes than the overt clinical condition. Facial affect processing is dependent on a distributed cortico-limbic network that is disrupted in psychosis. This study assessed facial affect processing and related brain structure as a candidate endophenotype of first-episode psychosis (FEP).

Three samples comprising 30 FEP patients, 30 of their first-degree relatives and 31 unrelated healthy controls underwent assessment of facial affect processing and structural magnetic resonance imaging (sMRI) data. Multivariate analysis (partial least squares, PLS) was used to identify a grey matter (GM) system in which anatomical variation was associated with variation in facial affect processing speed.

The groups did not differ in their accuracy of facial affect intensity rating but differed significantly in speed of response, with controls responding faster than relatives, who responded faster than patients. Within the control group, variation in speed of affect processing was significantly associated with variation of GM density in amygdala, lateral temporal cortex, frontal cortex and cerebellum. However, this association between cortico-limbic GM density and speed of facial affect processing was absent in patients and their relatives.

Speed of facial affect processing presents as a candidate endophenotype of FEP. The normal association between speed of facial affect processing and cortico-limbic GM variation was disrupted in FEP patients and their relatives.

Neural substrates of emotion dysregulation in adolescent suicide attempters remain unexamined.

We used functional magnetic resonance imaging to measure neural activity to neutral, mild or intense (i.e. 0%, 50% or 100% intensity) emotion face morphs in two separate emotion-processing runs (angry and happy) in three adolescent groups: (1) history of suicide attempt and depression (ATT, n = 14); (2) history of depression alone (NAT, n = 15); and (3) healthy controls (HC, n = 15). Post-hoc analyses were conducted on interactions from 3 group × 3 condition (intensities) whole-brain analyses (p < 0.05, corrected) for each emotion run.

To 50% intensity angry faces, ATT showed significantly greater activity than NAT in anterior cingulate gyral–dorsolateral prefrontal cortical attentional control circuitry, primary sensory and temporal cortices; and significantly greater activity than HC in the primary sensory cortex, while NAT had significantly lower activity than HC in the anterior cingulate gyrus and ventromedial prefrontal cortex. To neutral faces during the angry emotion-processing run, ATT had significantly lower activity than NAT in the fusiform gyrus. ATT also showed significantly lower activity than HC to 100% intensity happy faces in the primary sensory cortex, and to neutral faces in the happy run in the anterior cingulate and left medial frontal gyri (all p < 0.006,corrected). Psychophysiological interaction analyses revealed significantly reduced anterior cingulate gyral–insula functional connectivity to 50% intensity angry faces in ATT v. NAT or HC.

Elevated activity in attention control circuitry, and reduced anterior cingulate gyral–insula functional connectivity, to 50% intensity angry faces in ATT than other groups suggest that ATT may show inefficient recruitment of attentional control neural circuitry when regulating attention to mild intensity angry faces, which may represent a potential biological marker for suicide risk.

Both low birthweight and high birthweight have been associated with an increased risk for schizophrenia and cognitive impairments in the general population. We assessed the association between birthweight and cognitive performance in persons with schizophrenia and their unaffected first-degree relatives.

We investigated a population-based family sample comprising persons with schizophrenia (n = 142) and their unaffected first-degree relatives (n = 277). Both patients and relatives were interviewed with the Structured Clinical Interview for DSM-IV Axis I Disorders, Clinician Version (SCID-CV) and a comprehensive neuropsychological test battery was administered. Information on birthweight was obtained from obstetric records. We used generalized estimating equation (GEE) models to investigate the effect of birthweight, as a continuous variable, on cognitive functioning, adjusting for within-family correlation and relevant covariates.

Both low birthweight and high birthweight were associated with lower performance in visuospatial reasoning, processing speed, set-shifting and verbal and visual working memory among persons with schizophrenia and their unaffected first-degree relatives compared to individuals with birthweight in the intermediate range. The group × birthweight interactions were non-significant.

Both low birthweight and high birthweight are associated with deficits in cognition later in life. Schizophrenia does not seem to modify the relationship between birthweight and cognition in families with schizophrenia.

Bipolar disorder (BD) has been reported to be associated with high risk of suicide. We aimed to investigate the frequency and characteristics of suicide in people with BD in a national sample.

Suicide in BD in England from 1996 to 2009 was explored using descriptive statistics on data collected by the National Confidential Inquiry into Suicide and Homicide by People with Mental Illness (NCI). Suicide cases with a primary diagnosis of BD were compared to suicide cases with any other primary diagnosis.

During the study period 1489 individuals with BD died by suicide, an average of 116 cases/year. Compared to other primary diagnosis suicides, those with BD were more likely to be female, more than 5 years post-diagnosis, current/recent in-patients, to have more than five in-patient admissions, and to have depressive symptoms. In BD suicides the most common co-morbid diagnoses were personality disorder and alcohol dependence. Approximately 40% were not prescribed mood stabilizers at the time of death. More than 60% of BD suicides were in contact with services the week prior to suicide but were assessed as low risk.

Given the high rate of suicide in BD and the low estimates of risk, it is important that health professionals can accurately identify patients most likely to experience poor outcomes. Factors such as alcohol dependence/misuse, personality disorder, depressive illness and current/recent in-patient admission could characterize a high-risk group. Future studies need to operationalize clinically useful indicators of suicide risk in BD.

Anxiety disorders are very common and increase risk for suicide attempts. Little is known about predictors of increased risk specifically among individuals with anxiety disorders. The purpose of this study was to investigate whether specific anxiety disorders and other co-morbid psychiatric disorders, physical health, or work or social functioning increased the future likelihood of a suicide attempts among individuals with anxiety disorders.

In this prospective study, 676 individuals with an anxiety disorder were followed for an average of 12 years.

As hypothesized, we found that post-traumatic stress disorder, major depressive disorder (MDD), intermittent depressive disorder (IDD), epilepsy, pain, and poor work and social functioning all predicted a shorter time to a suicide attempt in univariate analyses. In multivariate analyses, baseline MDD and IDD were independent predictors of time to suicide attempt, even when controlling for a past history of suicide attempt. No specific anxiety disorder was an independent predictor of time to attempt in this anxiety-disordered sample. Adding baseline physical health variables and social functioning did not improve the ability of the model to predict time to suicide attempt.

Mood disorders and past history of suicide attempts are the most powerful predictors of a future suicide attempt in this sample of individuals, all of whom have an anxiety disorder.

Previous research has implicated the behavioral activation system (BAS) in depression. The relationship of BAS functioning to aspects of cognitive vulnerability to depression, however, is not known.

The present study investigated associations among level of BAS functioning and the encoding and recall of positive and negative self-referent information in currently non-depressed participants with a history of recurrent major depression (recovered; RMD) and in never-depressed control participants (CTL). Participants completed self-report measures of levels of BAS and behavioral inhibition system (BIS) functioning. Following a negative mood induction, participants were presented with a series of positive and negative adjectives; they indicated which words described them and later recalled as many of the words as they were able.

The relationship of BAS functioning to self-referent processing was dependent on participant group. Although lower BAS reward responsivity was associated with the endorsement and recall of fewer positive words across groups, the magnitude of these associations was stronger, and was only significant, within the RMD group. Furthermore, only for RMD participants was lower BAS reward responsivity associated with the endorsement of more negative words. These effects were not accounted for by depressive or anxiety symptoms, current mood, or level of BIS functioning.

These results indicate that BAS functioning may be distinctively linked to negatively biased self-referent processing, one facet of cognitive vulnerability to depression, in individuals with a history of major depressive disorder. Enhancing BAS functioning may be important in buffering cognitive vulnerability to depression.

Severe health anxiety is a common condition associated with functional disability, making it a costly disorder from a societal perspective. Internet-based cognitive behaviour therapy (ICBT) is a promising treatment but no previous study has assessed the cost-effectiveness or long-term outcome of ICBT for severe health anxiety. The aim of this study was to investigate the cost-effectiveness and 1-year treatment effects of ICBT for severe health anxiety.

Cost-effectiveness and 1-year follow-up data were obtained from a randomized controlled trial (RCT) comparing ICBT (n = 40) to an attention control condition (CC, n = 41). The primary outcome measure was the Health Anxiety Inventory (HAI). A societal perspective was taken and incremental cost-effectiveness ratios (ICERs) were calculated using bootstrap sampling.

The main ICER was −£1244, indicating the societal economic gain for each additional case of remission when administering ICBT. Baseline to 1-year follow-up effect sizes on the primary outcome measure were large (d = 1.71–1.95).

ICBT is a cost-effective treatment for severe health anxiety that can produce substantial and enduring effects.