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We and others have reported that patients experiencing their first episode of psychosis already have significant structural brain abnormalities. Antipsychotics seem to reverse subcortical volume deficits after months of treatment. However, the early impact of medication on brain morphology is not known.
Method
Forty-eight individuals in their first episode of psychosis underwent magnetic resonance imaging (MRI) brain scanning. Twenty-six were antipsychotic naive and 22 were newly treated with antipsychotic medication for a median period of 3 weeks. In each group, 80% of subjects received a diagnosis of schizophrenia. The two groups were balanced for age, sex, handedness, ethnicity, height, years of education, paternal socio-economic status (SES) and Positive and Negative Syndrome Scale (PANSS) score. Group differences in whole-brain grey matter were compared voxel by voxel, using Brain Activation and Morphological Mapping (BAMM) software. We also conducted testing of group differences with region-of-interest (ROI) measurements of the caudate nucleus.
Results
Relative to the untreated group, those receiving antipsychotic medication for 3–4 weeks had significantly greater grey-matter volumes in the bilateral caudate and cingulate gyri, extending to the left medial frontal gyrus. ROI analysis confirmed that, in treated patients, the right and left caudate nuclei were significantly larger by 10% (p<0.039, two-tailed) and 9% (p<0.048, two-tailed) respectively.
Conclusions
Early striatal grey-matter enlargement may occur within the first 3–4 weeks of antipsychotic treatment. Possible reasons for putative striatal hypertrophy and its implications are discussed.
The relationship between the Bali (Indonesia) bombings of October 2002 and suicide has not previously been investigated, despite anecdotal evidence of the economic and psychological consequences of these attacks.
Method
Suicide rates were calculated over the period 1994–2006 in three Bali regencies to determine whether suicide increased in the period following the first Bali bombings. Poisson regression and time-series models were used to assess the change in suicide rates by sex, age and area in the periods before and after October 2002.
Results
Suicide rates (age-adjusted) increased in males from an average of 2.84 (per 100 000) in the period pre-2002 to 8.10 in the period post-2002, and for females from 1.51 to 3.68. The greatest increases in suicide in the post-2002 period were in the age groups 20–29 and ⩾60 years, for both males and females. Tourist arrivals fell significantly after the bombings, and addition of tourism to models reduced relative risk estimates of suicide, suggesting that some of the increase may be attributable to the socio-economic effects of declines in tourism.
Conclusions
There was an almost fourfold increase in male suicide risk and a threefold increase in female suicide risk in the period following the 2002 bombings in Bali. Trends in tourism did not account for most of the observed increases. Other factors such as indirect socio-economic effects and Balinese notions of collective guilt and anxieties relating to ritual neglect are important in understanding the rise in suicide in the post-2002 period.
Several lines of research suggest a disturbance of reversal learning (reward and punishment processing, and affective switching) in patients with major depressive disorder (MDD). Obsessive–compulsive disorder (OCD) is also characterized by abnormal reversal learning, and is often co-morbid with MDD. However, neurobiological distinctions between the disorders are unclear. Functional neuroimaging (activation) studies comparing MDD and OCD directly are lacking.
Method
Twenty non-medicated OCD-free patients with MDD, 20 non-medicated MDD-free patients with OCD, and 27 healthy controls performed a self-paced reversal learning task in an event-related design during functional magnetic resonance imaging (fMRI).
Results
Compared with healthy controls, both MDD and OCD patients displayed prolonged mean reaction times (RTs) but normal accuracy. In MDD subjects, mean RTs were correlated with disease severity. Imaging results showed MDD-specific hyperactivity in the anterior insula during punishment processing and in the putamen during reward processing. Moreover, blood oxygen level-dependent (BOLD) responses in the dorsolateral prefrontal cortex (DLPFC) and the anterior PFC during affective switching showed a linear decrease across controls, MDD and OCD. Finally, the OCD group showed blunted responsiveness of the orbitofrontal (OFC)–striatal loop during reward, and in the OFC and anterior insula during affective switching.
Conclusions
This study shows frontal–striatal and (para)limbic functional abnormalities during reversal learning in MDD, in the context of generic psychomotor slowing. These data converge with currently influential models on the neuropathophysiology of MDD. Moreover, this study reports differential neural patterns in frontal–striatal and paralimbic structures on this task between MDD and OCD, confirming previous findings regarding the neural correlates of deficient reversal learning in OCD.
Schizophrenia patients show disturbances on a range of tasks that assess mentalizing or ‘Theory of Mind’ (ToM). However, these tasks are often developmentally inappropriate, make large demands on verbal abilities and explicit problem-solving skills, and involve after-the-fact reflection as opposed to spontaneous mentalizing.
Method
To address these limitations, 55 clinically stable schizophrenia out-patients and 44 healthy controls completed a validated Animations Task designed to assess spontaneous attributions of social meaning to ambiguous abstract visual stimuli. In this paradigm, 12 animations depict two geometric shapes ‘interacting’ with each other in three conditions: (1) ToM interactions that elicit attributions of mental states to the agents, (2) Goal-Directed (GD) interactions that elicit attributions of simple actions, and (3) Random scenes in which no interaction occurs. Verbal descriptions of each animation are rated for the degree of Intentionality attributed to the agents and for accuracy.
Results
Patients had lower Intentionality ratings than controls for ToM and GD scenes but the groups did not significantly differ for Random scenes. The descriptions of the patients less closely matched the situations intended by the developers of the task. Within the schizophrenia group, performance on the Animations Task showed minimal associations with clinical symptoms.
Conclusions
Patients demonstrated disturbances in the spontaneous attribution of mental states to abstract visual stimuli that normally evoke such attributions. Hence, in addition to previously established impairment on mentalizing tasks that require logical inferences about others' mental states, individuals with schizophrenia show disturbances in implicit aspects of mentalizing.
In patients with major depressive disorder (MDD), functional neuroimaging studies have reported an increased activation of the dorsolateral prefrontal cortex (DLPFC) during executive performance and working memory (WM) processing, and also an increased activation of the anterior cingulate cortex (ACC) during baseline conditions. However, the functional coupling of these cortical networks during WM processing is less clear.
Method
In this study, we used a verbal WM paradigm, event-related functional magnetic resonance imaging (fMRI) and multivariate statistical techniques to explore patterns of functional coupling of temporally dissociable dorsolateral prefrontal and cingulate networks. By means of independent component analyses (ICAs), two components of interest were identified that showed either a positive or a negative temporal correlation with the delay period of the cognitive activation task in both healthy controls and MDD patients.
Results
In a prefronto-parietal network, a decreased functional connectivity pattern was identified in depressed patients comprising inferior parietal, superior prefrontal and frontopolar regions. Within this cortical network, MDD patients additionally revealed a pattern of increased functional connectivity in the left DLPFC and the cerebellum compared to healthy controls. In a second, temporally anti-correlated network, healthy controls exhibited higher connectivity in the ACC, the ventrolateral and the superior prefrontal cortex compared to MDD patients.
Conclusions
These results complement and expand previous functional neuroimaging findings by demonstrating a dysconnectivity of dissociable prefrontal and cingulate regions in MDD patients. A disturbance of these dynamic networks is characterized by a simultaneously increased connectivity of the DLPFC during task-induced activation and increased connectivity of the ACC during task-induced deactivation.
A long-standing issue in the health anxiety literature is the extent to which health anxiety is a dimensional or a categorical construct. This study explores this question directly using taxometric procedures.
Method
Seven hundred and eleven working adults completed an index of health anxiety [the Whiteley Index (WI)] and indicated their current health status. Data from those who were currently healthy (n=501) and receiving no medical treatment were examined using three taxometric procedures: mean above minus below a cut (MAMBAC), maximum eigenvalue (MAXEIGEN) and L-mode factor analysis (L-MODE).
Results
Graphical representations (comparing actual to simulated data) and fit indices indicate that health anxiety is more accurately represented as a dimensional rather than a categorical construct.
Conclusions
Health anxiety is better represented as a dimensional construct. Implications for theory development and clinical practice are examined.
Few controlled studies have specifically investigated aspects of mental health care in relation to suicide risk among recently discharged psychiatric patients. We aimed to identify risk factors, including variation in healthcare received, for suicide within 3 months of discharge.
Method
We conducted a national population-based case-control study of 238 psychiatric patients dying by suicide within 3 months of hospital discharge, matched on date of discharge to 238 living controls.
Results
Forty-three per cent of suicides occurred within a month of discharge, 47% of whom died before their first follow-up appointment. The first week and the first day after discharge were particular high-risk periods. Risk factors for suicide included a history of self-harm, a primary diagnosis of affective disorder, recent last contact with services and expressing clinical symptoms at last contact with staff. Suicide cases were more likely to have initiated their own discharge and to have missed their last appointment with services. Patients who were detained for compulsory treatment at last admission, or who were subject to enhanced levels of aftercare, were less likely to die by suicide.
Conclusions
The weeks after discharge from psychiatric care represent a critical period for suicide risk. Measures that could reduce risk include intensive and early community follow-up. Assessment of risk should include established risk factors as well as current mental state and there should be clear follow-up procedures for those who have self-discharged. Recent detention under the Mental Health Act and current use of enhanced levels of aftercare may be protective.
Healthy adolescents, and adults who engage in reward-driven, risky behaviours, demonstrate poor decision-making ability. Decision making in deliberate self-harm (DSH), a reward-driven, high-risk behaviour, has received little attention. This study assessed decision making and problem solving in adolescents with current or past SH.
Method
Decision making and problem solving were assessed using the Iowa Gambling Task (IGT) and the Means–Ends Problem-Solving Procedure (MEPS) respectively in 133 adolescents (57 healthy and 22 depressed controls with no SH history and 54 with SH history). A second analysis separated the SH group into current (n=30) and past (n=24) SH.
Results
The collective performance of adolescents with SH history did not differ from depressed or healthy adolescents on the IGT. However, current self-harming adolescents had a trend towards more high-risk choices (p=0.06) than those with previous SH history and were the only group not to significantly improve over time, persisting with high-risk strategy throughout. Those who no longer self-harmed learnt to use a low-risk strategy similar to healthy and depressed controls. Recency of last SH episode correlated with IGT performance. Depressed participants performed well on the IGT but poorly on the MEPS. By contrast, both collective and divided SH groups had comparable MEPS scores to healthy controls, all performing better than depressed participants.
Conclusion
Poor decision making is present in adolescents who currently self-harm but not in those with previous history; improvement in decision-making skills may therefore be linked to cessation of self-harm. Depressed adolescents who do and do not self-harm may have distinct characteristics.
Generalized social phobia (GSP) involves the fear/avoidance of social situations whereas generalized anxiety disorder (GAD) involves an intrusive worry about everyday life circumstances. It remains unclear whether these, highly co-morbid, conditions represent distinct disorders or alternative presentations of a single underlying pathology. In this study, we examined stimulus-reinforcement-based decision making in GSP and GAD.
Method
Twenty unmedicated patients with GSP, 16 unmedicated patients with GAD and 19 age-, IQ- and gender-matched healthy comparison (HC) individuals completed the Differential Reward/Punishment Learning Task (DRPLT). In this task, the subject chooses between two objects associated with different levels of reward or punishment. Thus, response choice indexes not only reward/punishment sensitivity but also sensitivity to reward/punishment level according to between-object reinforcement distance.
Results
We found that patients with GAD committed a significantly greater number of errors than both the patients with GSP and the HC individuals. By contrast, the patients with GSP and the HC individuals did not differ in performance on this task.
Conclusions
These results link GAD with anomalous non-affective-based decision making. They also indicate that GSP and GAD are associated with distinct pathophysiologies.
Schizophrenia is a complex disorder with a high heritability. Family members have an increased risk not only for schizophrenia per se but also for schizophrenia spectrum disorders. Impairment of neuropsychological functions found in schizophrenia patients are also frequently observed in their relatives. The dystrobrevin-binding protein 1 (DTNBP1) gene located at chromosome 6p22.3 is one of the most often replicated vulnerability genes for schizophrenia. In addition, this gene has been shown to modulate general cognitive abilities both in healthy subjects and in patients with schizophrenia.
Method
In a sample of 521 healthy subjects we investigated an association between the DTNBP1 genotype [single nucleotide polymorphism (SNP) rs1018381], personality traits [using the NEO Five-Factor Inventory (NEO-FFI) and the Schizotypal Personality Questionnaire – Brief Version (SPQ-B)] and cognitive function (estimated IQ, verbal fluency, attention, working memory and executive function).
Results
Significantly lower scores on the SPQ-B (p=0.0005) and the Interpersonal Deficit subscale (p=0.0005) in carriers of the A-risk allele were detected. There were no differences in any of the cognitive variables between groups.
Conclusions
The results indicate that genetic variation of the DTNBP1 genotype might exert gene-specific modulating effects on schizophrenia endophenotypes at the population level.
Clinical depression involves persistent dysphoria, implicating impaired affect regulation or mood repair failure. However, there is comparatively little information about the mood repair repertoires of individuals with histories of clinical depression, how their repertories differ from that of never-depressed people, and whether particular types of mood repair responses differentially contribute to depression risk.
Method
Adult probands who had childhood-onset depressive disorder (n=215) and controls with no history of major mental disorder (n=122) reported which specific (cognitive, behavioral, interpersonal and somatic-sensory) responses they typically deploy when experiencing sad affect, including responses known to appropriately attenuate dysphoria (‘adaptive’ responses) and those known to exacerbate dysphoria in the short or long run (‘maladaptive’ responses). Subjects were longitudinally followed and evaluated.
Results
Remitted probands and probands in depressive episodes both reported a greater number of maladaptive responses and fewer adaptive responses to their own sadness than did controls, although probands did not have an absolute deficiency of adaptive responses. Maladaptive (but not adaptive) mood repair responses predicted future increases in depression symptoms and an increased probability of a recurrent depressive episode among probands (even after controlling for several clinical predictors of course). Post-hoc analyses revealed that maladaptive non-cognitive and maladaptive cognitive mood repair response sets each predicted depression outcomes.
Conclusions
Individuals with past and present episodes of depressive disorder report an array of cognitive and non-cognitive responses to their own sadness that are likely to exacerbate that affect, and this pattern predicts a worse course of the disorder.
Thematic section: A proposal for a meta-structure for DSM-V and ICD-11
In an effort to group mental disorders on the basis of etiology, five clusters have been proposed. Here we consider the validity of the cluster comprising selected psychotic and related disorders.
Method
A group of diagnostic entities classified under schizophrenia and other psychotic disorders in DSM-IV-TR were assigned to this cluster and the bordering disorders, bipolar (BD) and schizotypal personality disorders (SPD), were included. We then reviewed the literature in relation to 11 validating criteria proposed by the DSM-V Task Force Study Group.
Results
Relevant comparisons on the 11 spectrum criteria are rare for the included disorders except for schizophrenia and the two border conditions, BD and SPD. The core psychosis group is congruent at the level of shared psychotic psychopathology and response to antipsychotic medication. BD and SPD are exceptions in that psychosis is not typical in BD-II disorder and frank psychosis is excluded in SPD. There is modest similarity between schizophrenia and BD relating to risk factors, neural substrates, cognition and endophenotypes, but key differences are noted. There is greater support for a spectrum relationship of SPD and schizophrenia. Antecedent temperament, an important validator for other groupings, has received little empirical study in the various psychotic disorders.
Conclusions
The DSM-IV-TR grouping of psychotic disorders is supported by tradition and shared psychopathology, but few data exist across these diagnoses relating to the 11 spectrum criteria. The case for including BD is modest, and the relationship of BD to other mood disorders is addressed elsewhere. Evidence is stronger for inclusion of SPD, but the relationship with other personality disorders along the 11 criteria is not addressed and the absence of psychosis presents a conceptual problem. There are no data along the 11 spectrum criteria that are decisive for a cluster based on etiology, and inclusion of BD and SPD is questionable.
Anorexia nervosa (AN) is associated with behavioral traits that predate the onset of AN and persist after recovery. We identified patterns of behavioral traits in AN trios (proband plus two biological parents).
Method
A total of 433 complete trios were collected in the Price Foundation Genetic Study of AN using standardized instruments for eating disorder (ED) symptoms, anxiety, perfectionism, and temperament. We used latent profile analysis and ANOVA to identify and validate patterns of behavioral traits.
Results
We distinguished three classes with medium to large effect sizes by mothers' and probands' drive for thinness, body dissatisfaction, perfectionism, neuroticism, trait anxiety, and harm avoidance. Fathers did not differ significantly across classes. Classes were distinguished by degree of symptomatology rather than qualitative differences. Class 1 (~33%) comprised low symptom probands and mothers with scores in the healthy range. Class 2 (~43%) included probands with marked elevations in drive for thinness, body dissatisfaction, neuroticism, trait anxiety, and harm avoidance and mothers with mild anxious/perfectionistic traits. Class 3 (~24%) included probands and mothers with elevations on ED and anxious/perfectionistic traits. Mother–daughter symptom severity was related in classes 1 and 3 only. Trio profiles did not differ significantly by proband clinical status or subtype.
Conclusions
A key finding is the importance of mother and daughter traits in the identification of temperament and personality patterns in families affected by AN. Mother–daughter pairs with severe ED and anxious/perfectionistic traits may represent a more homogeneous and familial variant of AN that could be of value in genetic studies.
Many people suffering from mental disorders do not seek appropriate help. We have examined attitudes that further or hinder help-seeking for depression with an established socio-psychological model, the Theory of Planned Behaviour (TPB), comparing models for respondents with and without depressive symptoms.
Method
A qualitative preparatory study (n=29) elicited salient behavioural (BB), normative (NB) and control beliefs (CB) that were later included in the TPB questionnaire. Telephone interviews with a representative population sample in Germany (n=2303) started with a labelled vignette describing symptoms of a major depression, followed by items covering the components of the TPB. Intention to see a psychiatrist for the problem described was elicited at the beginning and at the end of the interview. We screened participants for current depressive symptoms using the mood subscale of the Patient Health Questionnaire (PHQ-9).
Results
In non-depressed respondents (n=2167), a TPB path model predicted 42% of the variance for the first and 51% for the second question on intention. In an analogous model for depressed respondents (n=136), these values increased to 50% and 61% respectively. Path coefficients in both models were similar. In both depressed and non-depressed persons, attitude towards the behaviour was more important than the subjective norm, whereas perceived behavioural control was of minor influence.
Conclusions
Willingness to seek psychiatric help for depression can largely be explained by a set of attitudes and beliefs as conceptualized by the TPB. Our findings suggest that changing attitudes in the general population are likely to effect help-seeking when people experience depressive symptoms.
Interpersonal communication problems are common among persons with schizophrenia and may be linked, in part, to deficits in theory of mind (ToM), the ability to accurately perceive the attitudes, beliefs and intentions of others. Particular difficulties might be expected in the processing of counterfactual information such as sarcasm or lies.
Method
The present study included 50 schizophrenia or schizo-affective out-patients and 44 demographically comparable healthy adults who were administered Part III of The Awareness of Social Inference Test (TASIT; a measure assessing comprehension of sarcasm versus lies) as well as measures of positive and negative symptoms and community functioning.
Results
TASIT data were analyzed using a 2 (group: patients versus healthy adults)×2 (condition: sarcasm versus lie) repeated-measures ANOVA. The results show significant effects for group, condition, and the group×condition interaction. Compared to controls, patients performed significantly worse on sarcasm but not lie scenes. Within-group contrasts showed that patients performed significantly worse on sarcasm versus lie scenes; controls performed comparably on both. In patients, performance on TASIT showed a significant correlation with positive, but not negative, symptoms. The group and interaction effects remained significant when rerun with a subset of patients with low-level positive symptoms. The findings for a relationship between TASIT performance and community functioning were essentially negative.
Conclusions
The findings replicate a prior demonstration of difficulty in the comprehension of sarcasm using a different test, but are not consistent with previous studies showing global ToM deficits in schizophrenia.
Aetiological studies of eating disorders would benefit from a solution to the problem of instability of eating disorder symptoms. We present an approach to defining an eating disorders phenotype based on the retrospective assessment of lifetime eating disorders symptoms to define a lifetime pattern of illness. We further validate this approach by testing the most common lifetime categories for differences in the prevalence of specific childhood personality traits.
Method
Ninety-seven females participated in this study, 35 with a current diagnosis of restricting anorexia nervosa, 32 with binge/purging subtype of anorexia nervosa and 30 with bulimia nervosa. Subjects were interviewed by a newly developed EATATE Lifetime Diagnostic Interview for a retrospective assessment of the lifetime course of eating disorders symptoms and childhood traits reflecting obsessive–compulsive personality.
Results
The data illustrate the extensive instability of the eating disorders diagnosis. Four most common lifetime diagnostic categories were identified that significantly differ in the prevalence of childhood traits. Perfectionism and rigidity were more common in groups with a longer duration of underweight status, longer episodes of severe food restriction, excessive exercising, and shorter duration of binge eating.
Conclusions
The assessment of lifetime symptoms may produce a more accurate definition of the eating disorders phenotype. Obsessive–compulsive traits in childhood may moderate the course producing longer periods of underweight status. These findings may have important implications for nosology, treatment and future aetiological studies of eating disorders.
Thematic section: A proposal for a meta-structure for DSM-V and ICD-11
The extant major psychiatric classifications DSM-IV, and ICD-10, are atheoretical and largely descriptive. Although this achieves good reliability, the validity of a medical diagnosis would be greatly enhanced by an understanding of risk factors and clinical manifestations. In an effort to group mental disorders on the basis of aetiology, five clusters have been proposed. This paper considers the validity of the fourth cluster, emotional disorders, within that proposal.
Method
We reviewed the literature in relation to 11 validating criteria proposed by a Study Group of the DSM-V Task Force, as applied to the cluster of emotional disorders.
Results
An emotional cluster of disorders identified using the 11 validators is feasible. Negative affectivity is the defining feature of the emotional cluster. Although there are differences between disorders in the remaining validating criteria, there are similarities that support the feasibility of an emotional cluster. Strong intra-cluster co-morbidity may reflect the action of common risk factors and also shared higher-order symptom dimensions in these emotional disorders.
Conclusion
Emotional disorders meet many of the salient criteria proposed by the Study Group of the DSM-V Task Force to suggest a classification cluster.
Schizophrenic patients have fewer offspring than the general population but it is unclear whether (i) this persists for more than one generation, (ii) the reduced fertility is compensated by increased fertility in unaffected relatives, (iii) sociodemographic factors confound or interact with the association, and (iv) patients with affective psychosis have a similar fertility disadvantage. This study measured biological fitness over two generations in patients with schizophrenia or affective psychosis, and their unaffected siblings.
Method
We conducted a historical cohort study using a Swedish birth cohort of 12 168 individuals born 1915–1929 and followed up until 2002. We compared biological fitness over two generations in patients with schizophrenia (n=58) or affective psychosis (n=153), and their unaffected siblings, with the population, adjusting for a range of sociodemographic variables from throughout the lifespan.
Results
Patients with schizophrenia had fewer children [fertility ratio (FR) 0.42, 95% confidence interval (CI) 0.29–0.61] and grandchildren (FR 0.51, 95% CI 0.33–0.80) than the population. Some of this reduction was related to lower marriage rates in schizophrenic patients. The unaffected siblings of schizophrenic patients showed no evidence of any compensatory increase in fitness, but there was a trend towards enhanced fertility among the offspring of schizophrenia patients. Patients with affective psychosis and their relatives did not differ from the general population on any fertility measure.
Conclusions
Schizophrenia, but not affective psychosis, is associated with reduced biological fertility; this disadvantage is partly explained by marital status and persists into the second generation.
Patients with obsessive–compulsive disorder (OCD) have to repeat their actions before feeling satisfied that the action reached its intended goal. Learning theory predicts that this may be due to a failure in the processing of external feedback.
Method
We examined the performance of 29 OCD patients and 28 healthy volunteers on an associative learning task, in which initial learning is based solely on external feedback signals. Feedback valence was manipulated with monetary gains and losses.
Results
As predicted, OCD patients were impaired during initial, external feedback-driven learning but not during later learning stages. The emotional salience of the feedback modulated learning during the initial stage in patients and controls alike. During later learning stages, however, patients approached near-normal performance with rewarding feedback but continued to produce deficient learning with punishing feedback.
Conclusion
OCD patients have a fundamental impairment in updating behavior based on the external outcome of their actions, possibly mediated by faulty error signals in response selection processes.
The literature suggests an association between obesity and schizophrenia but fat mass and fat-free mass, which have been shown to be more predictive of all-cause mortality than only waist circumference and obesity [body mass index (BMI) ⩾30 kg/m2], have not been reported in psychotic disorders. We examined the detailed body composition of people with different psychotic disorders in a large population-based sample.
Method
We used a nationally representative sample of 8082 adult Finns aged ⩾30 years with measured anthropometrics (height, weight, waist circumference, fat percentage, fat-free mass and segmental muscle mass). Psychiatric diagnoses were based on a consensus procedure utilizing the Structured Clinical Interview for DSM-IV (SCID)-interview, case-notes and comprehensive register data.
Results
Schizophrenia (including schizo-affective disorder) was associated with obesity [odds ratio (OR) 2.3, 95% confidence interval (CI) 1.5–3.6], abdominal obesity (waist circumference ⩾88 cm for women, ⩾102 cm for men) (OR 2.2, 95% CI 1.3–3.6) and with higher fat percentage (mean difference 3.8%, 95% CI 2.0–5.7%), adjusted for age and gender, than in the remaining sample. The associations between schizophrenia and low fat-free mass and decreased muscle mass on trunk and upper limbs became statistically significant after adjusting for BMI. After further adjusting for current antipsychotic medication, education, diet and smoking, schizophrenia remained associated with obesity (OR 1.9, 95% CI 1.1–3.6) and abdominal obesity (OR 3.8, 95% CI 1.5–9.4). Participants with affective psychoses did not differ from the general population.
Conclusions
Individuals with schizophrenia have metabolically unfavorable body composition, comprising abdominal obesity, high fat percentage and low muscle mass. This leads to increased risk of metabolic and cardiovascular diseases.