Treatment-resistant depression exacts a heavy price in treatment costs and lost productivity, reaching into the tens of billions of dollars, but its effects on the lives of patients are just as ...devastating. In this literature review, the authors summarize 62 studies documenting the disease’s toll on quality of life, personal financial resources, and general health. The average patient in the included studies had experienced nearly four earlier episodes of depression, had not responded to 4.7 drug trials, and continued to meet or nearly meet criteria for severe depression.
ObjectiveThis literature review assessed the burden of treatment-resistant depression in the United States by compiling published data about the clinical, societal, and economic outcomes associated with failure to respond to one or more adequate trials of drug therapy.MethodsPubMed and the Tufts Cost-Effectiveness Analyses Registry were searched for English-language articles published between January 1996 and August 2013 that collected primary data about treatment-resistant depression. Two researchers independently assessed study quality and extracted data.ResultsSixty-two articles were included (N=59,462 patients). Patients with treatment-resistant depression had 3.8±2.1 prior depressive episodes and illness duration of 4.4±3.3 years and had completed 4.7±2.7 unsuccessful drug trials involving 2.1±.3 drug classes. Response rates for treatment-resistant depression were 36%±1%. A total of 17%±6% of patients had prior suicide attempts (1.1±.2 attempts per patient). Quality-of-life scores (scale of 0–1, with 0 indicating death and 1 indicating perfect health) for patients with treatment-resistant depression were .41±.8 and .26±.8 points lower, respectively, than for patients who experienced remission or response. Annual costs for health care and lost productivity were $5,481 and $4,048 higher, respectively, for patients with treatment-resistant versus treatment-responsive depression.ConclusionsTreatment-resistant depression exacts a substantial toll on patients’ quality of life. At current rates of 12%–20% among all depressed patients, treatment-resistant depression may present an annual added societal cost of $29–$48 billion, pushing up the total societal costs of major depression by as much as $106–$118 billion. These findings underscore the need for research on the mechanisms of depression, new therapeutic targets, existing and new treatment combinations, and tests to improve the efficacy of and adherence to treatments for treatment-resistant depression.
Patients with schizophrenia often fail to respond to an initial course of therapy. This study systematically reviewed the societal and economic burden of treatment-resistant schizophrenia (TRS). ...Studies that described patients with TRS published 1996–2012 were included if they collected primary data on clinical, social, or economic outcomes. All studies were independently reviewed and extracted by at least two investigators. Sixty-five studies were identified. Almost 60% (SD 18%) of patients failed to achieve response after 23 weeks on antipsychotic drug therapy. Patients with TRS had high rates of smoking (56%), alcohol abuse (51%), substance abuse (51%), and suicide ideation (44%). The incidence of severe adverse events to treatment was 4% (SD 7%). Mean quality of life for patients who were unresponsive or intolerant to treatment was ∼20% lower than that of patients in remission. Annual costs for patients with schizophrenia are $15 500–$22 300 and are 3–11-fold higher for patients with TRS. TRS remains common and costly, despite availability of many treatment options, and contributes to a significant loss in patient quality of life. Although estimates in the literature vary greatly, TRS conservatively adds more than $34 billion in annual direct medical costs in the USA.
Abstract
Motivation
The number of significantly associated regions reported in genome-wide association studies (GWAS) for polygenic traits typically increases with sample size. A traditional tool for ...quality control and identification of significant regions has been a visual inspection of how significant and correlated genetic variants cluster within a region. However, while inspecting hundreds of regions, this subjective method can misattribute significance to some loci or neglect others that are significant.
Results
The GWAS quality score (GQS) identifies suspicious regions and prevents erroneous interpretations with an objective, quantitative and automated method. The GQS assesses all measured single nucleotide polymorphisms (SNPs) that are linked by inheritance to each other linkage disequilibrium (LD) and compares the significance of trait association of each SNP to its LD value for the reported index SNP. A GQS value of 1.0 ascribes a high level of confidence to the entire region and its underlying gene(s), while GQS values <1.0 indicate the need to closely inspect the outliers. We applied the GQS to published and non-published genome-wide summary statistics and report suspicious regions requiring secondary inspection while supporting the majority of reported regions from large-scale published meta-analyses.
Availability and implementation
The GQS code/scripts can be cloned from GitHub (https://github.com/Xswapnil/GQS/). The analyst can use whole-genome summary statistics to estimate GQS for each defined region. We also provide an online tool (http://35.227.18.38/) that gives access to the GQS. The quantitative measure of quality attributes by GQS and its visualization is an objective method that enhances the confidence of each genomic hit.
Supplementary information
Supplementary data are available at Bioinformatics online.
Summary
Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family, plays critical roles in the survival, growth, and maintenance of brain and peripheral neurons. We report the ...presence of BDNF protein in human platelets and its release upon agonist stimulation. The BDNF content of washed platelets varied widely, from 3.5 to 67 ng/ 4 X 10
8
platelets, averaging 25.2 ± 21.2 ng/4 X 10
8
platelets (mean ± SD). The BDNF concentration in platelet-poor plasma was low (1.7 ± 1.7 ng/ml, n = 11). Thrombin, collagen, the Ca
++
ionophore A23187, and shear stress each induced a rapid release of BDNF from platelets. Up to only half of platelet BDNF was secreted upon agonist stimulation, suggesting that platelets may have a non-releasable pool of BDNF, or that the released BDNF binds to a recognition site on the platelet surface and is internalized, as occurs with serotonin. However, the cognate BDNF receptor, TrkB, was not detected in platelets. Nevertheless, the ability of BDNF to bind washed platelets was shown by FACS analysis confocal microscopy and by the binding and apparent internalization of
125
I-BDNF by platelets. A very high affinity site (K
d
= 130 X 10
−15
M, ∼80 sites/platelet) and a moderately high affinity site (K
d
= 20 nM, ∼3750 sites/platelet) were identified. The BDNF content in two mega-karyocytic cell lines, DAMI and Meg-01, was only 0.1% of the content measured in platelets. No BDNF mRNA was detected by Northern blotting in these cell lines or in platelets. The pituitary gland was also ruled out as a source for platelet BDNF, since the BDNF content of rat platelets did not decrease 2 weeks after hypophysectomy. Thus, platelet BDNF is not acquired from the megakaryocyte or pituitary gland, but is probably acquired from other sources via the blood circulation. Platelets appear to bind, store and release BDNF upon activation at the site of traumatic injury to facilitate the repair of peripheral nerves or other tissues that contain TrkB.
Antidepressants are among the most widely prescribed medications, yet only 35-45% of patients achieve remission following an initial antidepressant trial. The financial burden of treatment failures ...in direct treatment costs, disability claims, decreased productivity, and missed work may, in part, derive from a mismatch between optimal and actual prescribed medications. The present 1 year blinded and retrospective study evaluated eight direct or indirect health care utilization measures for 96 patients with a DSM-IV-TR diagnosis of depressive or anxiety disorder. The eight measures were evaluated in relation to an interpretive pharmacogenomic test and reporting system, designed to predict antidepressant responses based on DNA variations in cytochrome P450 genes (CYP2D6, CYP2C19, CYP2C9 and CYP1A2), the serotonin transporter gene (SLC6A4) and the serotonin 2A receptor gene (5HTR2A). All subjects had been prescribed at least one of 26 commonly prescribed antidepressant or antipsychotic medications. Subjects whose medication regimen included a medication identified by the gene-based interpretive report as most problematic for that patient and are in the 'red bin' (medication status of 'use with caution and frequent monitoring'), had 69% more total health care visits, 67% more general medical visits, greater than three-fold more medical absence days, and greater than four-fold more disability claims than subjects taking drugs categorized by the report as in the green bin ('use as directed') or yellow bin ('use with caution'). There were no correlations between the number of medications taken and any of the eight healthcare utilization measures. These results demonstrate that retrospective psychiatric pharmacogenomic testing can identify past inappropriate medication selection, which led to increased healthcare utilization and cost.
Gene expression changes in neuropsychiatric and neurodegenerative disorders, and gene responses to therapeutic drugs, provide new ways to identify central nervous system (CNS) targets for drug ...discovery. This review summarizes gene and pathway targets replicated in expression profiling of human postmortem brain, animal models, and cell culture studies. Analysis of isolated human neurons implicates targets for Alzheimer's disease and the cognitive decline associated with normal aging and mild cognitive impairment. In addition to tau, amyloid-beta precursor protein, and amyloid-beta peptides (Abeta), these targets include all three high-affinity neurotrophin receptors and the fibroblast growth factor (FGF) system, synapse markers, glutamate receptors (GluRs) and transporters, and dopamine (DA) receptors, particularly the D2 subtype. Gene-based candidates for Parkinson's disease (PD) include the ubiquitin-proteosome system, scavengers of reactive oxygen species, brain-derived neurotrophic factor (BDNF), its receptor, TrkB, and downstream target early growth response 1, Nurr-1, and signaling through protein kinase C and RAS pathways. Increasing variability and decreases in brain mRNA production from middle age to old age suggest that cognitive impairments during normal aging may be addressed by drugs that restore antioxidant, DNA repair, and synaptic functions including those of DA to levels of younger adults. Studies in schizophrenia identify robust decreases in genes for GABA function, including glutamic acid decarboxylase, HINT1, glutamate transport and GluRs, BDNF and TrkB, numerous 14-3-3 protein family members, and decreases in genes for CNS synaptic and metabolic functions, particularly glycolysis and ATP generation. Many of these metabolic genes are increased by insulin and muscarinic agonism, both of which are therapeutic in psychosis. Differential genomic signals are relatively sparse in bipolar disorder, but include deficiencies in the expression of 14-3-3 protein members, implicating these chaperone proteins and the neurotransmitter pathways they support as possible drug targets. Brains from persons with major depressive disorder reveal decreased expression for genes in glutamate transport and metabolism, neurotrophic signaling (eg, FGF, BDNF and VGF), and MAP kinase pathways. Increases in these pathways in the brains of animals exposed to electroconvulsive shock and antidepressant treatments identify neurotrophic and angiogenic growth factors and second messenger stimulation as therapeutic approaches for the treatment of depression.
Abstract
Adverse events, response failures and medication non-compliance are common in patients receiving medications for the treatment of mental illnesses. A systematic literature review assessed ...whether pharmacokinetic (PK) or pharmacodynamic (PD) responses to 26 commonly prescribed antipsychotic and antidepressant medications, including efficacy or side effects, are associated with nucleotide polymorphisms in eight commonly studied genes in psychiatric pharmacotherapy: CYP2D6, CYP2C19, CYP2C9, CYP1A2, CYP3A4, HTR2C, HTR2A, and SLC6A4. Of the 294 publications included in this review, 168 (57%) showed significant associations between gene variants and PK or PD outcomes. Other studies that showed no association often had insufficient control for confounding variables, such as co-medication use, or analysis of medications not substrates of the target gene. The strongest gene-outcome associations were for the PK profiles of CYP2C19 and CYP2D6 (93% and 90%, respectively), for the PD associations between HTR2C and weight gain (57%), and for SLC6A4 and clinical response (54%), with stronger SLC6A4 response associations for specific drug classes (60-83%). The preponderance of evidence supports the validity of analyzing nucleotide polymorphisms in CYP and pharmacodynamic genes to predict the metabolism, safety, or therapeutic efficacy of psychotropic medications commonly used for the treatment of depression, schizophrenia, and bipolar illness.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The role of neurotrophins as target-derived proteins that promote neuron survival following their retrograde transport from the terminals to the cell bodies of neurons has been firmly established in ...the developing peripheral nervous system. However, neurotrophins appear to have more diverse functions, particularly in the adult central nervous system. Brain-derived neurotrophic factor (BDNF), for example, produces a variety of neuromodulatory effects in the brain that are more consistent with local actions than with long-distance retrograde signalling. Here we show that BDNF is widely distributed in nerve terminals, even in brain areas such as the striatum that lack BDNF messenger RNA, and that inhibition of axonal transport or deafferentation depletes BDNF. The number of striatal neurons that contain the calcium-binding protein parvalbumin was decreased in BDNF+/− and BDNF−/− mice in direct proportion to the loss of BDNF protein, which is consistent with anterogradely supplied BDNF having a functional role in development or maintenance. Thus the anterograde transport of BDNF from neuron cell bodies to their terminals may be important for the trafficking of BDNF in the brain.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background Aripiprazole (Abilify) is an atypical antipsychotic drug primarily characterized by partial agonist activity at dopamine (DA) D2 receptors and low side effects. Based on pharmacologic ...properties that include a stabilization of mesocorticolimbic DA activity, a pathway implicated in addiction, aripiprazole was tested for its ability to prevent relapse to cocaine seeking in rats. Methods We assessed the dose-dependent effects of aripiprazole on conditioned cue-induced and cocaine-primed reinstatement of drug-seeking behavior following chronic intravenous cocaine self-administration in an animal model of relapse. Results Aripiprazole potently and dose-dependently attenuated responding on the previously cocaine-paired lever during both reinstatement conditions, with slightly greater efficacy at reducing conditioned-cued reinstatement. Aripiprazole was effective at doses that failed to alter cocaine self-administration, food self-administration, reinstatement of food-seeking behavior, or basal locomotor activity, suggesting selective effects of aripiprazole on motivated drug-seeking behavior. Conclusions These results in a relapse model show that aripiprazole can block cocaine seeking without affecting other behaviors. The D2 partial agonist properties of aripiprazole likely account for the blockade of reinstatement of cocaine-seeking behavior. Given its established efficacy and tolerability as a treatment for psychosis, aripiprazole may be an excellent therapeutic choice for reducing craving and preventing relapse in people with cocaine dependency.
Hippocampal dentate granule neurons are altered in schizophrenia, but it is unknown if their gene expressions change in schizophrenia or other psychiatric diseases.
Laser-captured dentate granule ...neurons from two groups of schizophrenia and control cases and from major depression and bipolar disease cases were examined for alterations in gene expression using complementary DNA (cDNA) microarrays and reverse transcription polymerase chain reaction (RT-PCR).
Compared with 24 control cases, the 22 schizophrenia patients in both groups revealed decreases in clusters of genes that encode for protein turnover (proteasome subunits and ubiquitin), mitochondrial oxidative energy metabolism (isocitrate, lactate, malate, nicotinamide adenine dinucleotide NADH, and succinate dehydrogenases; cytochrome C oxidase; adenosine triphosphate ATP synthase), and genes associated with neurite outgrowth, cytoskeletal proteins, and synapse plasticity. These changes were not obtained in 9 bipolar cases or 10 major depression cases and were not associated with age, sex, brain weight, body weight, postmortem interval, or drug history. Brain pH contributed to the variance of some genes but was mostly independent of the disease effect.
Decreases in hippocampal neuron gene expression are consistent with brain imaging and microarray studies of the frontal cortex in schizophrenia. A mitochondrial and ubiquitin-proteasome hypofunctioning of dentate granule neurons may contribute to the deficits of schizophrenia.