Post-traumatic stress disorder (PTSD) has been called one of the signature injuries of the Iraq War. In this review prevalence estimates of PTSD are summarized and discrepancies are discussed in relation to methodological differences between studies.

We searched for population-based studies with a minimum sample size of 300. Studies based on help-seeking samples were excluded. We identified 60 possible papers, of which 19 fulfilled the inclusion criteria. Prevalence estimates and study characteristics were examined graphically with forest plots, but because of high levels of heterogeneity between studies, overall estimates of PTSD prevalence were not discussed.

The prevalence of PTSD in personnel deployed to Iraq varied between 1.4% and 31%. Stratifying studies by PTSD measure only slightly reduced the variability in prevalence. Anonymous surveys of line infantry units reported higher levels of PTSD compared to studies that are representative of the entire deployed population. UK studies tend to report lower prevalence of PTSD compared with many US studies; however, when comparisons are restricted to studies with random samples, prevalences are similar. US studies that have assessed personnel more than once since return from deployment have shown that PTSD prevalence increases over the 12 months following deployment.

Differences in methodologies and samples used should be considered when making comparisons of PTSD prevalence between studies. Further studies based on longitudinal samples are needed to understand how the prevalence of PTSD changes over time.

We conducted a systematic review to assess the evidence for specific effects of cannabis on brain structure and function. The review focuses on the cognitive changes associated with acute and chronic use of the drug.

We reviewed literature reporting neuroimaging studies of chronic or acute cannabis use published up until January 2009. The search was conducted using Medline, EMBASE, LILACS and PsycLIT indexing services using the following key words: cannabis, marijuana, delta-9-tetrahydrocannabinol, THC, cannabidiol, CBD, neuroimaging, brain imaging, computerized tomography, CT, magnetic resonance, MRI, single photon emission tomography, SPECT, functional magnetic resonance, fMRI, positron emission tomography, PET, diffusion tensor MRI, DTI-MRI, MRS and spectroscopy.

Sixty-six studies were identified, of which 41 met the inclusion criteria. Thirty-three were functional (SPECT/PET/fMRI) and eight structural (volumetric/DTI) imaging studies. The high degree of heterogeneity across studies precluded a meta-analysis. The functional studies suggest that resting global and prefrontal blood flow are lower in cannabis users than in controls. The results from the activation studies using a cognitive task are inconsistent because of the heterogeneity of the methods used. Studies of acute administration of THC or marijuana report increased resting activity and activation of the frontal and anterior cingulate cortex during cognitive tasks. Only three of the structural imaging studies found differences between users and controls.

Functional neuroimaging studies suggest a modulation of global and prefrontal metabolism both during the resting state and after the administration of THC/marijuana cigarettes. Minimal evidence of major effects of cannabis on brain structure has been reported.

The psychosocial vulnerability model of hostility posits that hostile individuals, given their oppositional attitudes and behaviours, are more likely to have increased interpersonal conflicts, lower social support, more stressful life events (SL-E) and higher likelihood of depression. However, little research has tested this hypothesis using large-scale prospective samples. The present study aims to assess the predictive value of hostility for depressive mood.

Data are from 3399 participants in the Whitehall II cohort study, aged 35–55 years at baseline (phase 1 1985–1988). Cynical hostility was measured at phase 1. Depressive mood was assessed at phase 7 (2002–2004). Sociodemographic characteristics, health-related behaviours, common mental disorders and antidepressant medication intake were assessed at phase 1. SL-E and confiding/emotional support were measured at phases 1, 2 (1989–1990) and 5 (1997–1999).

Compared with participants in the lowest quartile of cynical hostility, those in the highest quartiles were more likely to have depressive mood [second quartile: odds ratio (OR) 1.58, 95% confidence interval (CI) 1.14–2.20; third quartile: OR 2.78, 95% CI 2.03–3.77; fourth quartile: OR 4.66, 95% CI 3.41–6.36] in analysis adjusted for sociodemographic characteristics. This graded association was somewhat attenuated (⩽18%) but remained robust to adjustments for the covariates measured at baseline and follow-up. The association was also evident in participants free of mental health difficulties at baseline.

Cynical hostility is a strong and robust predictor of depressive mood. Consideration of personality characteristics may be crucial to the understanding and management of depression.

Dyadic discord, while common in depression, has not been specifically evaluated as an outcome predictor in chronic major depressive disorder. This study investigated pretreatment dyadic discord as a predictor of non-remission and its relationship to depressive symptom change during acute treatment for chronic depression.

Out-patients with chronic depression were randomized to 12 weeks of treatment with nefazodone, the Cognitive Behavioral Analysis System of Psychotherapy or their combination. Measures included the Marital Adjustment Scale (MAS) and the Inventory of Depressive Symptomatology – Self Report (IDS-SR30). Of 681 original patients, 316 were partnered and 171 of these completed a baseline and exit MAS, and at least one post-baseline IDS-SR30. MAS scores were analysed as continuous and categorical variables (‘dyadic discord’ v. ‘no dyadic discord’ defined as an MAS score >2.36. Remission was defined as an IDS-SR30 of ⩽14 at exit (equivalent to a 17-item Hamilton Rating Scale for Depression of ⩽7).

Patients with dyadic discord at baseline had lower remission rates (34.1%) than those without dyadic discord (61.2%) (all three treatment groups) (χ2=12.6, df=1, p=0.0004). MAS scores improved significantly with each of the treatments, although the change was reduced by controlling for improvement in depression. Depression remission at exit was associated with less dyadic discord at exit than non-remission for all three groups [for total sample, 1.8 v. 2.4, t(169)=7.3, p<0.0001].

Dyadic discord in chronically depressed patients is predictive of a lower likelihood of remission of depression. Couple therapy for those with dyadic discord may increase remission rates.

Previous imaging studies have revealed that acute major depression is characterized by altered neural responses to negative emotional stimuli. Typically, responses in limbic regions such as the amygdala are increased while activity in cortical regulatory regions such as the dorsolateral prefrontal cortex (DLPFC) is diminished. Whether these changes persist in unmedicated recovered patients is unclear.

We used functional magnetic resonance imaging to examine neural responses to emotional faces in a facial expression-matching task in 16 unmedicated recovered depressed patients and 21 healthy controls.

Compared with controls, recovered depressed patients had increased responses bilaterally to fearful faces in the DLPFC and right caudate. Responses in the amygdala did not distinguish the groups.

Our findings indicate that clinical recovery from depression is associated with increased activity in the DLPFC to negative emotional stimuli. We suggest that this increase may reflect a compensatory cortical control mechanism with the effect of limiting emotional dysregulation in limbic regions such as the amygdala.

Central to understanding of the behavioural consequences of depression has been the theory that the disorder is accompanied by an increased sensitivity to negative compared with positive reinforcement (negative bias), whereas other theorists have emphasized a global reduction in sensitivity to reinforcement in depression (blunting).

In this study, we used a probabilistic selection task that was designed to examine independently rates of learning to predict both positive and negative reinforcement. Twenty-three depressed out-patients and 23 healthy controls from the local population participated in the study.

No evidence for a negative bias was observed on the task, either during acquisition of the task or during generalization of the learned information. Depressed patients responded slower on the task than controls but showed a similar modulation of reaction times (RTs) as controls following reinforcement. Evidence for blunting was observed on the training phase, as reflected in reduced trial-by-trial adjustment during this phase. However, this effect was related specifically to the severity of anhedonia, as measured by the Snaith–Hamilton Pleasure Scale (SHAPS), and was independent of overall depression severity.

We argue that the observation of a negative bias or blunting in a group of depressed patients may be dependent on the neuropsychological task and the symptoms of the patients tested. Our results provide insight into how these theories might be further tested.

Limited evidence has suggested that quitting smoking increases the incidence of major depressive episodes (MDEs), particularly for smokers with a history of depression. Further evidence for this increase would have important implications for guiding smoking cessation.

Spanish- and English-speaking smokers without a current MDE (n=3056) from an international, online smoking cessation trial were assessed for abstinence 1 month after their initial quit date and followed for a total of 12 months. Incidence of screened MDE was examined as a function of abstinence and depression history.

Continued smoking, not abstinence, predicted MDE screened at 1 month [smoking 11.5% v. abstinence 7.8%, odds ratio (OR) 1.36, 95% confidence interval (CI) 1.04–1.78, p=0.02] but not afterwards (smoking 11.1% v. abstinence 9.8%, OR 1.05, 95% CI 0.77–1.45, p=0.74). Depression history predicted MDE screened at 1 month (history 17.1% v. no history 8.6%, OR 1.71, 95% CI 1.29–2.27, p<0.001) and afterwards (history 21.7% v. no history 8.3%, OR 3.87, 95% CI 2.25–6.65, p<0.001), although the interaction between history and abstinence did not.

Quitting smoking was not associated with increased MDE, even for smokers with a history of depression, although a history of depression was. Instead, not quitting was associated with increased MDE shortly following a quit attempt. Results from this online, large, international sample of smokers converge with similar findings from smaller, clinic-based samples, suggesting that in general, quitting smoking does not increase the incidence of MDEs.

The DSM-IV symptom criteria for major depressive disorder (MDD) are somewhat lengthy, with many studies showing that treatment providers have difficulty recalling all nine symptoms. Moreover, the criteria include somatic symptoms that are difficult to apply in patients with medical illnesses. In a previous report, we developed a briefer definition of MDD that was composed of the mood and cognitive symptoms of the DSM-IV criteria, and found high levels of agreement between the simplified and full DSM-IV definitions. The goal of the present study was to replicate these findings in another large sample of psychiatric out-patients and to extend the findings to other patient samples.

We interviewed 1100 psychiatric out-patients and 210 pathological gamblers presenting for treatment and 1200 candidates for bariatric surgery. All patients were interviewed by a diagnostic rater who administered a semi-structured interview. We inquired about all symptoms of depression for all patients.

In all three samples high levels of agreement were found between the DSM-IV and the simpler definition of MDD. Summing across all 2510 patients, the level of agreement between the two definitions was 95.5% and the κ coefficient was 0.87.

After eliminating the four somatic criteria from the DSM-IV definition of MDD, a high level of concordance was found between this simpler definition and the original DSM-IV classification. This new definition offers two advantages over the current DSM-IV definition – it is briefer and it is easier to apply with medically ill patients because it is free of somatic symptoms.

Previous research indicates that individuals with seasonal depression (SD) do not exhibit the memory biases for negative self-referent information that characterize non-seasonal depression (NSD). The current study extended this work by examining processing of self-referent emotional information concerning potential future events in SD.

SD and NSD patients, along with never-depressed controls, completed a scenario-based measure of likelihood estimation for future positive and negative events happening either to the self or to another person.

SD patients estimated future negative events as more likely to happen to both the self and others, relative to controls. In contrast, in the NSD sample this bias was specific to self-referred material. There were no group differences for positive events.

These data provide further evidence that the self-referent bias for processing negative information that characterizes NSD can be absent in SD, this time in the domain of future event processing.

Communication skills are considered ‘core skills’ in the curriculum of psychiatry but studies evaluating the effectiveness of a time-limited training course in interviewing skills in psychiatry have remained rare. The aim was to assess the effectiveness of training in patient-centred interviewing on the interview performance of psychiatric residents.

Psychiatric residents (n=10) each interviewed 12 different anonymized standardized patients (SPs), eight before and another four after training. SPs simulated psychiatric out-patients who attended for a first visit to the psychiatric out-patient clinic. The consultations were videotaped, transcribed and coded with a classification scheme developed for psychiatric consultations from which an interview performance index was derived. An interrupted time-series design and a segmented regression analysis with multilevel analysis explored the performance trend within the series of consultations.

The regression model evidenced a horizontal slope at pre- and post-training, with a significant level change. These findings excluded the presence of a practice effect and indicated a significant effect of training. Performance variability between and within residents over the series of consultations increased at post-training.

The training improved patient-centred interviewing performance. More post-training exercise time and supervised practice are necessary to establish consistent performance patterns at a higher skill level.

A consistent association between paternal age and their offspring's risk of schizophrenia has been observed, with no independent association with maternal age. The relationship of paternal and maternal ages with risk of bipolar affective disorders (BPAD) in the offspring is less clear. The present study aimed at testing the hypothesis that paternal age is associated with their offspring's risk of BPAD, whereas maternal age is not.

This population-based cohort study was conducted with individuals born in Sweden during 1973–1980 and still resident there at age 16 years. Outcome was first hospital admission with a diagnosis of BPAD. Hazard ratios (HRs) were calculated using Cox's proportional hazard regression.

After adjustment for all potential confounding variables except maternal age, the HR for risk of BPAD for each 10-year increase in paternal age was 1.28 [95% confidence interval (CI) 1.11–1.48], but this fell to 1.20 (95% CI 0.97–1.48) after adjusting for maternal age. A similar result was found for maternal age and risk of BPAD [HR 1.30 (95% CI 1.08–1.56) before adjustment for paternal age, HR 1.12 (95% CI 0.86–1.45) after adjustment]. The HR associated with having either parent aged 30 years or over was 1.26 (95% CI 1.01–1.57) and it was 1.45 (95% CI 1.16–1.81) if both parents were >30 years.

Unlike schizophrenia, the risk of BPAD seems to be associated with both paternal and maternal ages.

Although central nervous system (CNS) involvement in adult myotonic dystrophy type 1 (DM1) was described long ago, the large number of variables affecting the cognitive and personality profile have made it difficult to determine the effect of DM1 on the brain. The aim of this study was to define the cognitive and personality patterns in adult DM1 patients, and to analyse the relationship between these clinical patterns and their association with the underlying molecular defect.

We examined 121 adult DM1 patients with confirmed molecular CTG repeat expansion and 54 control subjects using comprehensive neuropsychological tests and personality assessments with the Millon Clinical Multiaxial Inventory (MCMI)-II. We used a multiple linear regression model to assess the effect of each variable on cognition and personality adjusted to the remainders.

Patients performed significantly worse than controls in tests measuring executive function (principally cognitive inflexibility) and visuoconstructive ability. In the personality profile, some paranoid and aggressive traits were predominant. Furthermore, there was a significant negative correlation between the CTG expansion size and many of the neuropsychological and personality measures. The molecular defect also correlated with patients' daytime somnolence.

Besides muscular symptomatology, there is significant CTG-dependent involvement of the CNS in adult DM1 patients. Our data indicate that the cognitive impairment predominantly affects the fronto-parietal lobe.

Previous findings revealed that the acquisition of new semantic concepts' labels was impaired in uncomplicated alcoholic patients. The use of errorless learning may therefore allow them to improve learning performance. However, the flexibility of the new knowledge and the memory processes involved in errorless learning remain unclear.

New concepts' labels acquisition was examined in 15 alcoholic patients and 15 control participants in an errorless learning condition compared with 19 alcoholic patients and 19 control subjects in a trial-and-error learning condition. The flexibility of the new information was evaluated using different photographs from those used in the learning sessions but representing the same concepts. All of the participants carried out an additional explicit memory task and an implicit memory task was also performed by subjects in the errorless learning condition.

The alcoholic group in the errorless condition differed significantly from the alcoholic group in the trial-and-error condition but did not differ from the two control groups. There was no significant difference between results in the learning test and the flexibility task. Finally, in the alcoholic group, the naming score in the learning test was correlated with the explicit memory score but not with the implicit memory score.

Using errorless learning, alcoholics improved their abilities to learn new concepts' labels. Moreover, new knowledge acquired with errorless learning was flexible. The errorless learning advantage may rely on explicit rather than implicit memory processes in these alcohol-dependent patients presenting only mild to moderate deficits of explicit memory capacities.

To investigate hedonic reactivity and the influence of unconscious emotional processes on the low sensitivity to positive reinforcement of food in anorexia nervosa (AN).

AN and healthy women were exposed to palatable food pictures just after a subliminal exposure to facial expressions (happy, disgust, fear and neutral faces), either while fasting or after a standardized meal (hunger versus satiety). Both implicit [facial electromyographic (EMG) activity from zygomatic and corrugator muscles, skin conductance, heart rate, and videotaped facial behavior] and explicit (self-reported pleasure and desire) measures of affective processes were recorded.

In contrast to healthy women, the AN patients did not display objective and subjective indices of pleasure to food pictures when they were in the hunger states. Pleasure to food cues (liking) was more affected than the desire to eat (wanting) in AN patients. Subliminal ‘fear faces’ increased corrugator muscle reactivity to food stimuli in fasting AN patients, as compared to controls.

The results suggest that unconscious fear cues increase the negative appraisal of alimentary stimuli in AN patients and thus contribute to decreased energy intake.

There is evidence that patients with chronic fatigue syndrome (CFS) have mild hypocortisolism. The clinical significance of this is unclear. We aimed to determine whether hypocortisolism exerted any effect on the response of CFS to cognitive behavioural therapy (CBT).

We measured 24-h urinary free cortisol (UFC) in 84 patients with Centers for Disease Control and Prevention (CDC)-defined CFS (of whom 64 were free from psychotropic medication) who then received CBT in a specialist, tertiary out-patient clinic as part of their usual clinical care. We also measured salivary cortisol output from 0800 to 2000 h in a subsample of 56 psychotropic medication-free patients.

Overall, 39% of patients responded to CBT after 6 months of treatment. Lower 24-h UFC output was associated with a poorer response to CBT but only in psychotropic medication-free patients. A flattened diurnal profile of salivary cortisol was also associated with a poor response to CBT.

Low cortisol is of clinical relevance in CFS, as it is associated with a poorer response to CBT. Hypocortisolism could be one of several maintaining factors that interact in the persistence of CFS.