Identification and genetic determination of an early life risk disposition for depressive disorder : atypical stress-related behaviour in early childhood

Progress in psychiatric genetics has been slow despite evidence of high heritability for most mental disorders. We argue that greater use of early detectable intermediate traits (endophenotypes) with the highest likely aetiological significance to depression, rather than complex clinical phenotypes, would be advantageous. Longitudinal data from the Western Australian Pregnancy Cohort (Raine) Study were used to identify an early life behavioural endophenotype for atypical hypothalamic-pituitaryadrenocortical function in adolescence, a neurobiological indicator of anxiety and depression. A set of descriptors representing rigid and reactive behaviour at age 1 year discriminated those in the top 20% of the free salivary cortisol exposure at age 17 years. Genetic association analysis revealed a male-sensitive effect to variation in three specific single nucleotide polymorphisms within selected genes underpinning the overall stress response. Furthermore, support for a polygenic effect on stress-related behaviour in childhood is presented.

A consensus statement for safety monitoring guidelines of treatments for major depressive disorder

Objective: This paper aims to present an overview of screening and safety considerations for the treatment of clinical depressive disorders and make recommendations for safety monitoring.
Method: Data were sourced by a literature search using MEDLINE and a manual search of scientific journals to identify relevant articles. Draft guidelines were prepared and serially revised in an iterative manner until all co-authors gave final approval of content.
Results: Screening and monitoring can detect medical causes of depression. Specific adverse effects associated with antidepressant treatments may be reduced or identified earlier by baseline screening and agent-specific monitoring after commencing treatment.
Conclusion: The adoption of safety monitoring guidelines when treating clinical depression is likely to improve overall physical health status and treatment outcome. It is important to implement these guidelines in the routine management of clinical depression.

The neuroprogressive nature of major depressive disorder: pathways to disease evolution and resistance, and therapeutic implications

In some patients with major depressive disorder (MDD), individual illness characteristics appear consistent with those of a neuroprogressive illness. Features of neuroprogression include poorer symptomatic, treatment and functional outcomes in patients with earlier disease onset and increased number and length of depressive episodes. In such patients, longer and more frequent depressive episodes appear to increase vulnerability for further episodes, precipitating an accelerating and progressive illness course leading to functional decline. Evidence from clinical, biochemical and neuroimaging studies appear to support this model and are informing novel therapeutic approaches. This paper reviews current knowledge of the neuroprogressive processes that may occur in MDD, including structural brain consequences and potential molecular mechanisms including the role of neurotransmitter systems, inflammatory, oxidative and nitrosative stress pathways, neurotrophins and regulation of neurogenesis, cortisol and the hypothalamic–pituitary–adrenal axis modulation, mitochondrial dysfunction and epigenetic and dietary influences. Evidence-based novel treatments informed by this knowledge are discussed.

The health-related quality of life burden of co-morbid cardiovascular disease and major depressive disorder in Australia : findings from a population-based, cross-sectional study

Purpose Health-related quality of life (HRQOL) can be significantly impaired by the presence of chronic conditions such as cardiovascular disease (CVD) and major depressive disorder (MDD). The aim of this paper was to (1) identify differences in HRQOL between individuals with CVD, MDD, or both, compared to a healthy reference group, (2) establish whether the influence of co-morbid MDD and CVD on HRQOL is additive or synergistic and (3) determine the way in which depression severity interacts with CVD to influence overall HRQOL.

Methods Population-based data from the 2007 Australian National Survey of Mental Health and Well-being (NSMHWB) (n = 8841) were used to compare HRQOL of individuals with MDD and CVD, MDD but not CVD, CVD but not MDD, with a healthy reference group. HRQOL was measured using the Assessment of Quality of Life (AQOL). MDD was identified using the Composite International Diagnostic Interview (CIDI 3.0).

Results Of all four groups, individuals with co-morbid CVD and depression reported the greatest deficits in AQOL utility scores (Coef: −0.32, 95% CI: −0.40, −0.23), after adjusting for covariates. Those with MDD only (Coef: −0.27, 95% CI: −0.30, −0.24) and CVD only (Coef: −0.08, 95% CI: −0.11, −0.05) also reported reduced AQOL utility scores. Second, the influence of MDD and CVD on HRQOL was shown to be additive, rather than synergistic. Third, a significant dose–response relationship was observed between depression severity and HRQOL. However, CVD and depression severity appeared to act independently of each other in impacting HRQOL.

Conclusions HRQOL is greatly impaired in individuals with co-morbid MDD and CVD; these conditions appear to influence HRQOL in an additive fashion. HRQOL alters with depression severity, therefore treating depression and improving HRQOL is of clinical importance.

Malondialdehyde plasma concentration correlates with declarative and working memory in patients with recurrent depressive disorder

Oxidative stress has been implicated in the cognitive decline, especially in memory impairment. The purpose of this study was to determine the concentration of malondialdehyde (MDA) in patients with recurrent depressive disorders (rDD) and to define relationship between plasma levels of MDA and the cognitive performance. The study comprised 46 patients meeting criteria for rDD. Cognitive function assessment was based on: The Trail Making Test , The Stroop Test, Verbal Fluency Test and Auditory-Verbal Learning Test. The severity of depression symptoms was assessed using the Hamilton Depression Rating Scale (HDRS). Statistically significant differences were found in the intensity of depression symptoms, measured by the HDRS on therapy onset versus the examination results after 8 weeks of treatment (P < 0.001). Considering the 8-week pharmacotherapy period, rDD patients presented better outcomes in cognitive function tests. There was no statistically significant correlation between plasma MDA levels, and the age, disease duration, number of previous depressive episodes and the results in HDRS applied on admission and on discharge. Elevated levels of MDA adversely affected the efficiency of visual-spatial and auditory-verbal working memory, short-term declarative memory and the delayed recall declarative memory. 1. Higher concentration of plasma MDA in rDD patients is associated with the severity of depressive symptoms, both at the beginning of antidepressants pharmacotherapy, and after 8 weeks of its duration. 2. Elevated levels of plasma MDA are related to the impairment of visual-spatial and auditory-verbal working memory and short-term and delayed declarative memory.

Total antioxidant status correlates with cognitive impairment in patients with recurrent depressive disorder

Depressive disorder is a multifactorial diseases, that one of the typical feature are cognitive impairments. The aim of this study was to determine the total antioxidant status (TAS) in patients with recurrent depressive disorder (rDD) and to define relationship between plasma levels of TAS and the cognitive performance. Design and methods: the study comprised 74 subjects: patients with rDD (n = 45) and healthy subjects (n = 29). Cognitive function assessment was based on: Trail Making Test, The Stroop Test, Verbal Fluency Test and Auditory Verbal Learning Test. Statistically significant differences were found in the intensity of depression symptoms, measured by the Hamilton Depression Rating Scale (HDRS) on therapy onset versus the examination results after 8 weeks of treatment (p < 0.001). The level of TAS was substantially higher in patients with rDD (p = 0.01). For rDD patients, elevated TAS levels were associated with worse cognitive test performance. The higher was the concentration of plasma TAS, the greater was the severity of depressive symptoms measured by HDRS before and after pharmacotherapy. (1) Higher concentration of plasma TAS in rDD patients is associated with the severity of depressive symptoms. (2) Elevated levels of plasma TAS are related to impairment of short-term declarative memory, long-term declarative-memory, verbal fluency and working memory.

The relationship between coronary heart disease (CHD) and major depressive disorder (MDD) : key mechanisms and the role of quality of life

Various trials have been conducted evaluating depression management programs for patients with Coronary Heart Disease (CHD). However, to date, the most effective way to manage this co-morbidity in the real world setting remains unclear. To better understand the past successes and failures of previous trials and subsequently develop suitable interventions that target key components of health related quality of life (HRQOL) such as mental, physical and vocational functioning, we first need to understand the mechanisms underpinning the relationship between the two conditions. This paper will draw on the key literature in this field as identified by psychiatric, medical and social sciences databases (Cochrane Central Register of Controlled Trials, PubMed, OVID, Medline) available up to January 2012, with the aim to conduct a narrative review which explores: the aetiological relationship between depression and CHD; its association with HRQOL; the relationship between CHD, depression and vocational functioning; and the impact of depression treatment on these outcomes. Key recommendations are made regarding the management of this prevalent co-morbidity in clinical settings.

Treatment response for acute depression is not associated with number of previous episodes: lack of evidence for a clinical staging model for major depressive disorder

Mental illness has been observed to follow a neuroprogressive course, commencing with prodrome, then onset, recurrence and finally chronic illness. In bipolar disorder and schizophrenia responsiveness to treatment mirrors these stages of illness progression, with greater response to treatment in the earlier stages of illness and greater treatment resistance in chronic late stage illness.

Using data from 5627 participants in 15 controlled trials of duloxetine, comparator arm (paroxetine, venlafaxine, escitalopram) or placebo for the treatment of an acute depressive episode, the relationship between treatment response and number of previous depressive episodes was determined. Data was dichotomised for comparisons between participants who had >3 previous episodes (n=1697) or ≤3 previous episodes (n=3930), and additionally for no previous episodes (n=1381) or at least one previous episode (n=4246). Analyses were conducted by study arm for each clinical trial, and results were then pooled.

There was no significant difference between treatment response and number of previous depressive episodes. This unexpected finding suggests that treatments to reduce symptoms of depression during acute illness do not lose efficacy for patients with a longer history of illness.

The shared role of oxidative stress and inflammation in major depressive disorder and nicotine dependence

Nicotine dependence is common in people with mood disorders; however the operative pathways are not well understood. This paper reviews the contribution of inflammation and oxidative stress pathways to the co-association of depressive disorder and nicotine dependence, including increased levels of pro-inflammatory cytokines, increased acute phase proteins, decreased levels of antioxidants and increased oxidative stress. These could be some of the potential pathophysiological mechanisms involved in neuroprogression. The shared inflammatory and oxidative stress pathways by which smoking may increase the risk for development of depressive disorders are in part mediated by increased levels of pro-inflammatory cytokines, diverse neurotransmitter systems, activation the hypothalamic-pituitary-adrenal (HPA) axis, microglial activation, increased production of oxidative stress and decreased levels of antioxidants. Depressive disorder and nicotine dependence are additionally linked imbalance between neuroprotective and neurodegenerative metabolites in the kynurenine pathway that contribute to neuroprogression. These pathways provide a mechanistic framework for understanding the interaction between nicotine dependence and depressive disorder.