Australian & New Zealand Journal of Psychiatry

Bipolar disorder is a chronic, severe and disabling disease; however, its pathophysiology remains poorly understood. Recent evidence has suggested that inflammation and immune dysregulation play a significant role in the pathophysiology of bipolar disorder. This review is aimed to highlight the importance of systemic inflammation in modulating the inflammatory response of microglia and hence its potential involvement with bipolar disorder. We also discuss novel therapeutic strategies that emerge from this new research.

This article presents a theoretical synthesis of the effects of systemic inflammation on the immune response of the central nervous system in bipolar disorder. The complex relationship between stress, pro-inflammatory cytokines and microglial dysfunction is summarized, emphasizing the role of the kynurenine pathway in this process and, consequently, their effects on neuronal plasticity.

Bipolar patients demonstrate increased serum levels of pro-inflammatory cytokines (interleukin-1β, interleukin-6 and tumor necrosis factor-α) and lower hypothalamic–pituitary–adrenal axis sensitivity. This imbalance in the immune system promotes a change in blood–brain barrier permeability, leading to an inflammatory signal spread in the central nervous system from the periphery, through macrophages activation (M1 polarization). Chronic microglial activation can result in neuronal apoptosis, neurogenesis inhibition, hippocampal volume reduction, lower neurotransmitters synthesis and cytotoxicity, by increasing glutamate production and kynurenine metabolism.

This review provides an overview of the mechanisms involved in the immune system imbalance and its potential involvement in the pathophysiology of bipolar disorder. Consequently, new strategies that normalize the immune-inflammatory pathways may provide a valuable therapeutic target for the treatment of these disorders.

There are mounting calls for bipolar disorder to be managed in primary care, yet the exact prevalence remains unclear. We conducted a meta-analysis to investigate the prevalence of bipolar disorder in general primary care attendees without other comorbid psychiatric diagnosis.

We systematically searched major electronic databases from inception till 03/2015. Articles were included that reported the prevalence of bipolar disorder determined in line with structured clinical assessment in primary care settings. Two independent authors conducted searches, completed methodological appraisal and extracted data. A random effects meta-analysis and meta-regression were performed.

Sixteen studies were included accounting for 425,691 participants (mean age = 41.1 years [standard deviation = 7.2 years] 33.3% males). Overall, the global prevalence of bipolar disorder was 1.9% (95% confidence interval = [0.6, 5.4]). The prevalence of bipolar disorder in studies recording a current diagnosis was 3.7% (95% confidence interval = [1.9, 6.0]) and 0.7% (95% confidence interval = [0.2, 1.5]) in studies considering a 12-month period. A diagnosis of bipolar disorder appeared higher in North America (3.7%, 95% confidence interval = [0.9, 8.1]) compared to Europe (0.8%, 95% confidence interval = [0.3, 1.5]). Meta-regression suggests that a more recent publication date (co-efficient = 0.089, 95% confidence interval = [0.0173, 0.1654], z = 2.19, p = 0.01, R² = 0.21) and younger age of participants (co-efficient −0.0851, 95% confidence interval = [−0.1696, 0.005], z = −1.97, p = 0.04, R² = 0.24) moderated a higher prevalence of bipolar disorder.

The global prevalence of bipolar disorder in primary care is 1.9%, with potentially higher prevalence rates in North America compared to Europe. A more recent study publication date is a significant predictor of higher prevalence of bipolar disorder. Potential reasons/drivers of this are considered within the text.

In clinical settings, there is substantial evidence both clinically and empirically to suggest that approximately 50% of individuals with borderline personality disorder experience auditory verbal hallucinations. However, there is limited research investigating the phenomenology of these voices. The aim of this study was to review and compare our current understanding of auditory verbal hallucinations in borderline personality disorder with auditory verbal hallucinations in patients with a psychotic disorder, to critically analyse existing studies investigating auditory verbal hallucinations in borderline personality disorder and to identify gaps in current knowledge, which will help direct future research.

The literature was searched using the electronic database Scopus, PubMed and MEDLINE. Relevant studies were included if they were written in English, were empirical studies specifically addressing auditory verbal hallucinations and borderline personality disorder, were peer reviewed, used only adult humans and sample comprising borderline personality disorder as the primary diagnosis, and included a comparison group with a primary psychotic disorder such as schizophrenia.

Our search strategy revealed a total of 16 articles investigating the phenomenology of auditory verbal hallucinations in borderline personality disorder. Some studies provided evidence to suggest that the voice experiences in borderline personality disorder are similar to those experienced by people with schizophrenia, for example, occur inside the head, and often involved persecutory voices. Other studies revealed some differences between schizophrenia and borderline personality disorder voice experiences, with the borderline personality disorder voices sounding more derogatory and self-critical in nature and the voice-hearers’ response to the voices were more emotionally resistive. Furthermore, in one study, the schizophrenia group’s voices resulted in more disruption in daily functioning. These studies are, however, limited in number and do not provide definitive evidence of these differences.

The limited research examining auditory verbal hallucinations experiences in borderline personality disorder poses a significant diagnostic and treatment challenge. A deeper understanding of the precise phenomenological characteristics will help us in terms of diagnostic distinction as well as inform treatments.

Emergency workers, such as fire-fighters, are routinely exposed to potentially traumatic events. While a number of studies have examined the occurrence of post-traumatic stress disorder, the role of multiple traumas on other mental health sequelae, such as depression and alcohol misuse, among emergency workers remains unclear. This study aimed to assess the prevalence of post-traumatic stress disorder, depression and alcohol misuse in a sample of current and retired fire-fighters and examine their relationship with cumulative trauma exposure.

A cross-sectional survey was completed by current (n = 488) and retired (n = 265) fire-fighters from Fire and Rescue New South Wales, Australia. Demographic and occupational information was collected, including the number of fatal incidents fire-fighters reported attending across years of service. Validated, self-report measures were used to determine probable caseness for post-traumatic stress disorder, depression and heavy drinking.

Among current fire-fighters, rates of post-traumatic stress disorder and depression were 8% and 5%, respectively, while 4% reported consumption of more than 42 alcoholic drinks per week. Retired fire-fighters reported significantly greater levels of symptomatology, with the prevalence estimates of post-traumatic stress disorder at 18% (p = 0.001), depression at 18% (p < 0.001) and heavy drinking at 7%. There was a significant positive linear relationship between the number of fatal incidents attended and rates of post-traumatic stress disorder, depression and heavy drinking.

Fire-fighters suffer from high rates of mental disorders, with rates of post-traumatic stress disorder, depression and heavy drinking continuing to rise in a linear manner with each additional trauma exposure. The level of psychiatric morbidity among retired fire-fighters appears to be particularly high. Our findings have important implications for the ongoing debates surrounding the detection of mental disorders in high-risk occupations and for policy considerations around the welfare of current and retired emergency workers.

This study was designed to assess the levels of and associations between gay-related stressful events, social support, emotional distress and the number of unprotected anal intercourse partners among Chinese men who have sex with men.

Using a respondent-driven sampling method, 807 men who have sex with men were recruited in urban areas of northeast China and data were collected via face-to-face interviews. Gay-related stressful events were measured using the Gay-Related Stressful Life Events Scale; levels of depression, anxiety symptoms and social support were measured using the Self-Rating Depression Scale, the Self-Rating Anxiety Scale and the Social Support Rating Scale, respectively.

Over a quarter of study participants experienced gay-related stressful events during the preceding 3 months. Their average Self-Rating Depression Scale, Self-Rating Anxiety Scale and Social Support scores differed significantly from the national norm. Gay-related stressful events significantly correlated with anxiety (r = 0.167, p < 0.001), depression (r = 0.165, p < 0.001), social support (r = −0.107, p = 0.002) and number of unprotected anal intercourse partners (r = 0.13, p < 0.001), showing a clear dose–response relationship.

Gay-related stressful events are common and are significantly associated with emotional distress, lack of social support and high-risk sexual behaviors among Chinese men who have sex with men. Multifaceted approaches are warranted to increase social support and reduce intolerance toward homosexual behaviors and to reduce risky sexual behaviors related to the rapid HIV epidemic among men who have sex with men population in China.

Individuals with bipolar disorder experience a disproportionately high incidence of medical co-morbidity and obesity. These health-related problems are a barrier to recovery from mood episodes and have been linked with unfavorable responses to pharmacological treatment. However, little is known about whether and how these characteristics affect responses to adjunctive psychotherapy.

Embedded in the Systematic Treatment Enhancement Program for Bipolar Disorder was a randomized controlled trial of psychotherapy for bipolar depression comparing the efficacy of intensive psychotherapy plus pharmacotherapy with collaborative care (a three-session psycho-educational intervention) plus pharmacotherapy. We conducted a post-hoc analysis to evaluate whether medical burden and body mass index predicted and/or moderated the likelihood of recovery and time until recovery from a depressive episode among patients in the two treatments.

Participants who had medical co-morbidity and body mass index data constituted 199 of the 293 patients in the original Systematic Treatment Enhancement Program for Bipolar Disorder trial. Higher medical burden predicted a lower likelihood of recovery from depression in both treatment conditions (odds ratio = 0.89), but did not moderate responses to intensive psychotherapy vs collaborative care. Intensive psychotherapy yielded superior recovery rates for individuals of normal body mass index (odds ratio= 2.39) compared with collaborative care, but not among individuals who were overweight or obese.

Medical co-morbidity and body weight impacts symptom improvement and attention to this co-morbidity may inform the development of more personalized treatments for bipolar disorder.

Given the burden of common psychiatric disorders and their consequent service and planning requirements, it is important to have a thorough knowledge of their distribution and characteristics in the population. Thus, we aimed to report the prevalence and age of onset of mood, anxiety and substance-use disorders in an age-stratified representative sample of Australian men.

Psychiatric disorders (mood, anxiety and substance-use disorders) were diagnosed utilising a structured clinical interview (Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders–Fourth Edition, Non-Patient Edition) for 961 men aged 24–98 years enrolled in the Geelong Osteoporosis Study. The lifetime and current prevalence of these disorders was determined from the study population and standardised to 2006 census data for Australia.

Approximately one in three men (28.8%, 95% confidence interval [CI] = [26.8%, 30.8%]) reported a lifetime history of any psychiatric disorder, with mood disorders (18.2%, 95% CI = [15.2%, 21.2%]) being more prevalent than anxiety (7.2%, 95% CI = [5.0%, 9.4%]) and substance-use disorders (12.9%, 95% CI = [9.7%, 16.0%]). Approximately 8.7% (95% CI = [7.5%, 10.0%]) were identified as having a current disorder, with 3.8% (95% interquartile range [IQR] = [2.2%, 5.4%]), 2.4% (95% CI = [1.1%, 3.8%]) and 3.4% (95% CI = [1.8%, 4.9%]) meeting criteria for current mood, anxiety and substance-use disorders, respectively. The median age of onset for mood disorders was 37.5 years (IQR = 27.0–48.0 years), 25.0 years (IQR = 20.0–40.3 years) for anxiety and 22.0 years (IQR = 18.0–34.3 years) for substance-use disorders.

This study reports the lifetime and current prevalence of psychiatric disorders in the Australian male population. These findings emphasise the extent of the burden of these disorders in the community.

People with chronic schizophrenia have high rates of physical ill-health such as heart disease. However, there has been less attention to the issue of poor oral health including dental caries (tooth decay) and periodontal (gum) disease, although both have consequences for quality of life and systemic physical health. We therefore measured tooth decay and gum disease in Malaysians with schizophrenia.

We recruited long-stay inpatients with schizophrenia from June to October 2014. Four dental specialists assessed oral health using the decayed–missing–filled teeth index, the Community Periodontal Index of Treatment Needs and the Debris Index of the Simplified Oral Hygiene Index. Results were compared with the 2010 Oral Health survey of the general Malaysian population.

A total of 543 patients participated (66.7% males, 33.3% females; mean age = 54.8 years [standard deviation = 16.0]) with a mean illness duration of 18.4 years (standard deviation = 17.1). The mean decayed–missing–filled teeth was 20.5 (standard deviation = 9.9), almost double that of the general population (11.7). Higher decayed–missing–filled teeth scores were associated with both older age (p < 0.001) and longer illness duration (p = 0.048). Only 1% (n = 6) had healthy gums. Levels of decay and periodontal disease were greatest in those aged between 45 and 64 years, coinciding with the onset of tooth loss.

Dental disease in people with schizophrenia deserves the same attention as other comorbid physical illness. The disparity in oral health is most marked for dental decay. Possible interventions include oral health assessments using standard checklists designed for non-dental personnel, help with oral hygiene, management of iatrogenic dry mouth and early dental referral.