Role of serotonin transporter polymorphisms in the behavioural and psychological symptoms in probable Alzheimer disease patients

Role of Serotonergic System in Regulating Brain Tumor-Associated Neuroinflammatory Responses

Serotonin signaling regulates wide arrays of both neural and extra-neural functions. Serotonin is also found to affect cancer progression directly as well as indirectly by modulating the immune cells. In the brain, serotonin plays a key role in regulating various functions; disturbance of the normal activities of serotonin leads to various mental illnesses, including the neuroinflammatory response in the central nervous system (CNS). The neuroinflammatory response can be initiated in various psychological illnesses and brain cancer. Serotonergic signaling can impact the functions of both glial as well as the immune cells. It can also affect the tumor immune microenvironment and the inflammatory response associated with brain cancers. Apart from this, many drugs used for treatment of psychological illness are known to modulate serotonergic system and can cross the blood-brain barrier. Understanding the role of serotonergic pathways in regulating neuroinflammatory response and brain cancer will provide a new paradigm in modulating the serotonergic components in treating brain cancer and associated inflammation-induced brain damages.

Extreme enhancement or depletion of serotonin transporter function and serotonin availability in autism spectrum disorder

A variety of human and animal studies support the hypothesis that serotonin (5-hydroxytryptamine or 5-HT) system dysfunction is a contributing factor to the development of autism in some patients. However, many questions remain about how developmental manipulation of various components that influence 5-HT signaling (5-HT synthesis, transport, metabolism) persistently impair social behaviors. This review will summarize key aspects of central 5-HT function important for normal brain development, and review evidence implicating perinatal disruptions in 5-HT signaling in the pathophysiology of autism spectrum disorder. We discuss the importance, and relative dearth, of studies that explore the possible correlation to autism in the interactions between important intrinsic and extrinsic factors that may disrupt 5-HT homeostasis during development. In particular, we focus on exposure to 5-HT transport altering mechanisms such as selective serotonin-reuptake inhibitors or genetic polymorphisms in primary or auxiliary transporters of 5-HT, and how they relate to neurological stores of serotonin and its precursors. A deeper understanding of the many mechanisms by which 5-HT signaling can be disrupted, alone and in concert, may contribute to an improved understanding of the etiologies and heterogeneous nature of this disorder. We postulate that extreme bidirectional perturbations of these factors during development likely compound or synergize to facilitate enduring neurochemical changes resulting in insufficient or excessive 5-HT signaling, that could underlie the persistent behavioral characteristics of autism spectrum disorder.

Hydroxytryptamine transporter gene-linked polymorphic region (5HTTLPR) is associated with delusions in Alzheimer's disease

BACKGROUND

Serotoninergic pathways underlying delusion symptoms in Alzheimer's disease (AD) have not been fully clarified. 5-Hydroxytryptamine transporter gene-linked polymorphic region (5-HTTLPR) is a variable number tandem repeats in the promoter region of serotonin transporter encoding-gene affecting transcription.

METHODS

We investigated the association of 5-HTTLPR with delusions in a total of 257 consecutive patients clinically diagnosed as AD according to the National Institute on Aging-Alzheimer's Association criteria. All participants underwent a comprehensive evaluation with a standardized comprehensive geriatric assessment and Neuropsychiatric Inventory.

RESULTS

Delusion symptoms were observed in 171 patients (66.54%). In respect to AD patients without delusions, AD patients with delusions showed a low prevalence of S-plus carriers (5-HTTLPR-L/S + 5-HTTLPR-S/S genotypes) [p < 0.001; odds ratio (OR) = 0.240, 95% confidence interval (CI) = 0.121-0.471]. Logistic regression analysis adjusted for the apolipoprotein E polymorphism showed that in AD patients with delusions the presence of an 5-HTTLPR-S allele may reduce disease duration (p = 0.005; OR = 0.680, 95% CI = 0.522-0.886) and increase aberrant motor activity (p = 0.013; OR = 2.257, 95% CI = 1.195-4.260). The present findings suggested that 5-HTTLPR might be associated with delusions in AD. S-plus carriers might be associated with protective effect against delusions in AD.

CONCLUSIONS

More studies on wider samples of high selected demented patients are needed to confirm our results. However, the present findings suggested that a genetic factor related to serotonin metabolism might exert a protective role on the clinical expression of neuropsychiatric clusters in AD with important implications regarding mechanisms underlying delusions and their possible treatment across the AD and dementia spectrum.

Targeted genotyping of variable number tandem repeats with adVNTR

Whole-genome sequencing is increasingly used to identify Mendelian variants in clinical pipelines. These pipelines focus on single-nucleotide variants (SNVs) and also structural variants, while ignoring more complex repeat sequence variants. Here, we consider the problem of genotyping Variable Number Tandem Repeats (VNTRs), composed of inexact tandem duplications of short (6–100 bp) repeating units. VNTRs span 3% of the human genome, are frequently present in coding regions, and have been implicated in multiple Mendelian disorders. Although existing tools recognize VNTR carrying sequence, genotyping VNTRs (determining repeat unit count and sequence variation) from whole-genome sequencing reads remains challenging. We describe a method, adVNTR, that uses hidden Markov models to model each VNTR, count repeat units, and detect sequence variation. adVNTR models can be developed for short-read (Illumina) and single-molecule (Pacific Biosciences [PacBio]) whole-genome and whole-exome sequencing, and show good results on multiple simulated and real data sets.

Association Study and Meta-Analysis of Polymorphisms, Methylation Profiles, and Peripheral mRNA Expression of the Serotonin Transporter Gene in Patients with Alzheimer's Disease

BACKGROUND/AIM

The aim of this study was to elucidate the relationship between Alzheimer's disease (AD) and the serotonin transporter gene (SLC6A4).

METHODS

AD subjects (n = 43) and controls (n = 47) were recruited and evaluated. In leukocytes, we evaluated two polymorphisms in SLC6A4, the serotonin transporter length polymorphic region (5-HTT-LPR) and rs25531, as well as methylation rates of the SLC6A4 promoter region and the SLC6A4 mRNA expression level. We also performed a meta-analysis to examine the relationship between the frequency of the L allele and the risk of AD.

RESULTS

The distributions of 5-HTT-LPR and rs25531 polymorphisms in AD subjects were not different from those of controls. Although the methylation rates in AD subjects were not significantly different from those of controls, the expression level in AD subjects was significantly higher than in controls. Additionally, the expression level in AD subjects was significantly correlated with apathy. Meta-analysis revealed that the L/L genotype significantly reduced the risk of AD, but only in the Caucasian population.

CONCLUSION

Higher SLC6A4 mRNA expression in leukocytes in AD was associated with apathy regardless of SLC6A4 genotypes and methylation rates of the promoter region. The L/L genotype may reduce the risk of AD in the Caucasian population.

[Neuropsychiatric disorders in dementia: mechanisms and treatment approach]

Behavioral and psychological symptoms of dementia can manifest at various stages during the disease. Prominence and rate of progression may depend on nosological form of dementia as well as environmental factors, concomitant diseases et al. Each psychiatric symptom is based on the specific neurotransmitter imbalance and differentiated involvement of various parts of the Central Nervous System in the pathological process. Treatment in each case should be chosen individually taking into account the balance of benefits and risks of prescribed drugs.

Genetics of psychosis of Alzheimer disease

Psychotic symptoms, comprised of delusions and hallucinations, occur in about half of individuals with Alzheimer disease (AD with psychosis, AD+P). These individuals have greater agitation, aggression, depression, functional impairment, and mortality than individuals without psychosis (AD-P). Although the exact etiopathogenesis of AD+P is unclear, the rapidly developing field of genomics continues to expand our understanding of this disease. Several independent studies have demonstrated familial aggregation and heritability of AD+P. Linkage studies have been suggestive of loci on several chromosomes associated with AD+P. Association studies examining apolipoprotein E gene, the best established genetic risk factor for late-onset AD, did not find any significant association of this gene with AD+P. Other candidate gene studies focusing on monoamine neurotransmitter systems have yielded equivocal results. A genome-wide association study and studies examining copy number variations recently have detected suggestive associations, but have been underpowered. Approaches to increase sizes of AD+P samples for genome wide association studies are discussed. © 2016 Wiley Periodicals, Inc.

Biomarkers of aggression in dementia

Dementia is a clinical syndrome defined by progressive global impairment of acquired cognitive abilities. It can be caused by a number of underlying conditions. The most common types of dementia are Alzheimer's disease (AD), frontotemporal dementia (FTD), vascular cognitive impairment (VCI) and dementia with Lewy bodies (DLB). Despite the fact that cognitive impairment is central to the dementia, noncognitive symptoms, most commonly described nowadays as neuropsychiatric symptoms (NPS) exist almost always at certain point of the illness. Aggression as one of the NPS represents danger both for patients and caregivers and the rate of aggression correlates with the loss of independence, cognitive decline and poor outcome. Therefore, biomarkers of aggression in dementia patients would be of a great importance. Studies have shown that different genetic factors, including monoamine signaling and processing, can be associated with various NPS including aggression. There have been significant and multiple neurotransmitter changes identified in the brains of patients with dementia and some of these changes have been involved in the etiology of NPS. Aggression specific changes have also been observed in neuropathological studies. The current consensus is that the best approach for development of such biomarkers may be incorporation of genetics (polymorphisms), neurobiology (neurotransmitters and neuropathology) and neuroimaging techniques.

Serotonergic drugs for the treatment of neuropsychiatric symptoms in dementia

Behavioral and psychological symptoms of dementia (known also as neuropsychiatric symptoms) are essential features of Alzheimer's disease and related dementias. The near universal presence of neuropsychiatric symptoms in dementia (up to 90% of cases) has brought significant attention of clinicians and experts to the field. Non-pharmacological and pharmacological interventions are recommended for various types of neuropsychiatric symptoms. However, most pharmacological interventions for the treatment of behavioral and psychological symptoms of dementia are used off-label in many countries. Cognitive decline and neuropsychiatric symptoms can be linked to alterations in multiple neurotransmitter systems, so modification of abnormalities in specific systems may improve clinical status of patients with neuropsychiatric symptoms. Use of serotonergic compounds (novel particles acting on specific receptors and widely acting drugs) in the treatment of neuropsychiatric symptoms is reviewed.

Yokukansan improves behavioral and psychological symptoms of dementia by suppressing dopaminergic function

Although three drugs, risperidone, yokukansan, and fluvoxamine, have shown equal efficacy in treating behavioral and psychological symptoms of dementia (BPSD) in our previous study, their mechanisms of action are different from one another. Monoamines have attracted attention for their key roles in mediating several behavioral symptoms or psychological symptoms through synaptic signaling. We aimed to clarify the monoamines changed by treatment with each drug in patients with BPSD. The main purpose of this study was to determine whether plasma levels of catecholamine metabolites are correlated with pharmacological treatments. This was an 8-week, rater-blinded, randomized, flexible-dose, triple-group trial. In total, 90 subjects were recruited and subsequently three different drugs were allocated to 82 inpatients with BPSD. We examined BPSD data from patients who completed 8 weeks of treatment. Eventually, we analyzed 42 patients (yokukansan: 17; risperidone: 9; fluvoxamine: 16). Homovanillic acid, a metabolite of dopamine, and 3-methoxy-4-hydroxyphenylglycol, a metabolite of noradrenaline, in their plasma were analyzed by high-performance liquid chromatography with electrochemical detection. All three drugs showed equal significant efficacy between baseline and study endpoint. By contrast, biomarkers showed mutually different changes. Patients in the yokukansan group had significantly decreased plasma homovanillic acid levels from baseline. Conversely, patients in the risperidone and fluvoxamine groups exhibited no significant changes in plasma homovanillic acid levels from baseline. Yokukansan contains geissoschizine methyl ether, which is known to have a partial agonist effect on dopamine D2 receptors. An improvement in BPSD condition with the intake of yokukansan is suggested to occur through a suppressed dopaminergic function, which is similar to the effect of aripiprazole.

Factors Related to Rejection of Care and Behaviors Directed towards Others: A Longitudinal Study in Nursing Home Residents with Dementia

Aims

The aim of this study was to analyze factors related to rejection of care and behaviors directed towards others in nursing home residents with dementia.

Methods

The relationship of lack of understanding, depression, psychosis and pain with rejection of care and behaviors directed towards others was explored using four assessments from the Minimum Data Set (MDS) within a period of 15 months on 1,101 residents with dementia in Dutch nursing homes. Presence of depressive symptoms was ascertained using a validated MDS scale, and presence of lack of understanding, rejection of care, psychosis and pain through the individual MDS items. A structural equation modeling approach and latent growth models were used to investigate the longitudinal relationship between changes in rejection of care and physical or verbal behaviors directed towards others, and changes in lack of understanding, pain, depression and psychotic symptoms.

Results

Changes in lack of understanding predicted changes in rejection of care, and there was also a relationship between changes in depression and rejection of care. Changes of behaviors directed towards others were related to changes in lack of understanding and depression. Pain and behaviors directed towards others were unrelated, and psychosis was rather stable throughout. A mediation model suggested that the relationship of lack of understanding with behaviors directed towards others was mediated by rejection of care.

Conclusion

These results indicate that lack of understanding and depression are important factors in development of rejection of care and behaviors directed towards others. The relationship between lack of understanding and behaviors directed towards others is mediated by rejection of care. Improvement in communication between residents and caregivers, and perhaps also effective treatment of depression may prevent or ameliorate these behaviors directed towards others.

VNTRseek-a computational tool to detect tandem repeat variants in high-throughput sequencing data

DNA tandem repeats (TRs) are ubiquitous genomic features which consist of two or more adjacent copies of an underlying pattern sequence. The copies may be identical or approximate. Variable number of tandem repeats or VNTRs are polymorphic TR loci in which the number of pattern copies is variable. In this paper we describe VNTRseek, our software for discovery of minisatellite VNTRs (pattern size ≥ 7 nucleotides) using whole genome sequencing data. VNTRseek maps sequencing reads to a set of reference TRs and then identifies putative VNTRs based on a discrepancy between the copy number of a reference and its mapped reads. VNTRseek was used to analyze the Watson and Khoisan genomes (454 technology) and two 1000 Genomes family trios (Illumina). In the Watson genome, we identified 752 VNTRs with pattern sizes ranging from 7 to 84 nt. In the Khoisan genome, we identified 2572 VNTRs with pattern sizes ranging from 7 to 105 nt. In the trios, we identified between 2660 and 3822 VNTRs per individual and found nearly 100% consistency with Mendelian inheritance. VNTRseek is, to the best of our knowledge, the first software for genome-wide detection of minisatellite VNTRs. It is available at http://orca.bu.edu/vntrseek/.

Behavioral and psychological symptoms in Alzheimer's disease

Neuropsychiatric symptoms (NPS) such as depression, apathy, aggression, and psychosis are now recognized as core features of Alzheimer's disease (AD), and there is a general consensus that greater symptom severity is predictive of faster cognitive decline, loss of independence, and even shorter survival. Whether these symptoms result from the same pathogenic processes responsible for cognitive decline or have unique etiologies independent of AD-associated neurodegeneration is unclear. Many structural and metabolic features of the AD brain are associated with individual neuropsychiatric symptoms or symptom clusters. In addition, many genes have been identified and confirmed that are associated with symptom risk in a few cases. However, there are no single genes strongly predictive of individual neuropsychiatric syndromes, while functional and structural brain changes unique to specific symptoms may reflect variability in progression of the same pathological processes. Unfortunately, treatment success for these psychiatric symptoms may be lower when comorbid with AD, underscoring the importance of future research on their pathobiology and treatment. This review summarizes some of the most salient aspects of NPS pathogenesis.

Cognitive impairment in studies of 5HTTLPR and psychosis in Alzheimer's disease: a systematic review

BACKGROUND/AIMS

Cognitive impairment is a well-established correlate of psychotic symptoms in Alzheimer's disease (AD-P). We review whether this relationship has confounded previous genetic association studies of 5HTTLPR and AD-P.

METHODS

We reviewed all studies on 5HTTLPR and conducted a semi-quantitative analysis.

RESULTS

Three out of 4 studies with low MMSE reported a significant association, while 1 out of 4 with high MMSE reported a significant association.

CONCLUSIONS

Variation in cognitive impairment in past studies has contributed to the inconsistency in findings. The findings presented here bring a greater clarity to our understanding of the role of 5HTTLPR in AD-P.

NMDA Neurotransmission Dysfunction in Behavioral and Psychological Symptoms of Alzheimer's Disease

Dementia has become an all-important disease because the population is aging rapidly and the cost of health care associated with dementia is ever increasing. In addition to cognitive function impairment, associated behavioral and psychological symptoms of dementia (BPSD) worsen patient’s quality of life and increase caregiver’s burden. Alzheimer’s disease is the most common type of dementia and both behavioral disturbance and cognitive impairment of Alzheimer’s disease are thought to be associated with the N-methyl-D-aspartate (NMDA) dysfunction as increasing evidence of dysfunctional glutamatergic neurotransmission had been reported in behavioral changes and cognitive decline in Alzheimer’s disease. We review the literature regarding dementia (especially Alzheimer’s disease), BPSD and relevant findings on glutamatergic and NMDA neurotransmission, including the effects of memantine, a NMDA receptor antagonist, and NMDA-enhancing agents, such as D-serine and D-cycloserine. Literatures suggest that behavioral disturbance and cognitive impairment of Alzheimer’s disease may be associated with excitatory neurotoxic effects which result in impairment of neuronal plasticity and degenerative processes. Memantine shows benefits in improving cognition, function, agitation/aggression and delusion in Alzheimer’s disease. On the other hand, some NMDA modulators which enhance NMDA function through the co-agonist binding site can also improve cognitive function and psychotic symptoms. We propose that modulating NMDA neurotransmission is effective in treating behavioral and psychological symptoms of Alzheimer’s disease. Prospective study using NMDA enhancers in patients with Alzheimer’s disease and associated behavioral disturbance is needed to verify this hypothesis.

A new single-photon emission computed tomography (SPECT) imaging agent for serotonin transporters: [(125)I]Flip-IDAM, (2-((2-((dimethylamino)methyl)-4-iodophenyl)thio)phenyl)methanol

New ligands for in vivo brain imaging of serotonin transporter (SERT) with single photon emission tomography (SPECT) were prepared and evaluated. An efficient synthesis and radiolabeling of a biphenylthiol, FLIP-IDAM, 4, was accomplished. The affinity of FLIP-IDAM was evaluated by an in vitro inhibitory binding assay using [(125)I]-IDAM as radioligand in rat brain tissue homogenates (K(i) = 0.03 nM). New [(125)I]Flip-IDAM exhibited excellent binding affinity to SERT binding sites with a high hypothalamus to cerebellum ratio of 4 at 30 min post iv injection. The faster in vivo kinetics for brain uptake and a rapid washout from non-specific regions provide excellent signal to noise ratio. This new agent, when labeled with (123)I, may be a useful imaging agent for mapping SERT binding sites in the human brain.

No association of COMT val158met polymorphism and psychotic symptoms in Lewy body dementias

We sought to determine whether the COMT val158met polymorphism (rs4680) is associated with delusions and hallucinations in people with dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD). A total of 218 individuals, recruited from centres in Norway, Sweden and the UK were included in this study; 121 with clinically or neuropathologically diagnosed DLB/PDD and 97 age-matched, cognitively normal controls. All participants with dementia underwent serial evaluation of neuropsychiatric symptoms to assess the presence of persistent delusions and hallucinations using the Columbia University Scale for Psychopathology in Alzheimer's disease, the Neuropsychiatric Inventory or the Present Behavioural Examination. Severity of cognitive impairment was measured using the Mini Mental State Examination (MMSE). Both controls and participants with dementia were genotyped for rs4680. In contrast to previous findings, analysis by logistic regression failed to find any associations between rs4680 and psychotic symptoms. Larger studies in well characterised cohorts are warranted in order to investigate this relationship further.

Genetics of aggression

Aggression mediates competition for food, mating partners, and habitats and, among social animals, establishes stable dominance hierarchies. In humans, abnormal aggression is a hallmark of neuropsychiatric disorders and can be elicited by environmental factors acting on an underlying genetic susceptibility. Identifying the genetic architecture that predisposes to aggressive behavior in people is challenging because of difficulties in quantifying the phenotype, genetic heterogeneity, and uncontrolled environmental conditions. Studies on mice have identified single-gene mutations that result in hyperaggression, contingent on genetic background. These studies can be complemented by systems genetics approaches in Drosophila melanogaster, in which mutational analyses together with genome-wide transcript analyses, artificial selection studies, and genome-wide analysis of epistasis have revealed that a large segment of the genome contributes to the manifestation of aggressive behavior with widespread epistatic interactions. Comparative genomic analyses based on the principle of evolutionary conservation are needed to enable a complete dissection of the neurogenetic underpinnings of this universal fitness trait.

Psychotropic drug effects on gene transcriptomics relevant to Alzheimer disease

Psychotropics are widely prescribed in Alzheimer disease (AD) without regard to their pathobiological effects. Results summarize a comprehensive survey of psychotropic effects on messenger ribonucleic acid (mRNA) expression for 52 genes linked to AD. Pending future investigations, current data indicate that atypical antipsychotics, lithium, and fluoxetine reduce AD risk, whereas other drug classes promote risk. Risk may be attenuated by antipsychotics and lithium (down-regulate TNF), atypical antipsychotics (down-regulate TF), risperidone (down-regulates IL1B), olanzapine (up-regulates TFAM, down-regulates PRNP), fluoxetine (up-regulates CLU, SORCS1, NEDD9, GRN, and ECE1), and lithium coadministered with antipsychotics (down-regulates IL1B). Risk may be enhanced by neuroleptics (up-regulate TF), haloperidol (up-regulates IL1B and PION), olanzapine (down-regulates THRA and PRNP, up-regulates IL1A), and chlorpromazine, imipramine, maprotiline, fluvoxamine, and diazepam (up-regulate IL1B). There were no results for dextromethorphan-plus-quinidine. Fluoxetine effects on CLU, NEDD9, and GRN were statistically robust. Drug effects on specific variants, polymorphisms, genotypes, and other genes (CCR2, TF, and PRNP) are detailed. Translational AD risk applications and their limitations related to specific genes, mutations, variants, polymorphisms, genotypes, brain site, sex, clinical population, AD stage, and other factors are discussed. This report provides an initial summary and framework to understand the potential impact of psychotropic drugs on AD-relevant genes.

Cerebral correlates of psychotic syndromes in neurodegenerative diseases

Psychosis has been recognized as a common feature in neurodegenerative diseases and a core feature of dementia that worsens most clinical courses. It includes hallucinations, delusions including paranoia, aggressive behaviour, apathy and other psychotic phenomena that occur in a wide range of degenerative disorders including Alzheimer's disease, synucleinopathies (Parkinson's disease, dementia with Lewy bodies), Huntington's disease, frontotemporal degenerations, motoneuron and prion diseases. Many of these psychiatric manifestations may be early expressions of cognitive impairment, but often there is a dissociation between psychotic/behavioural symptoms and the rather linear decline in cognitive function, suggesting independent pathophysiological mechanisms. Strictly neuropathological explanations are likely to be insufficient to explain them, and a large group of heterogeneous factors (environmental, neurochemical changes, genetic factors, etc.) may influence their pathogenesis. Clinico-pathological evaluation of behavioural and psychotic symptoms (PS) in the setting of neurodegenerative and dementing disorders presents a significant challenge for modern neurosciences. Recognition and understanding of these manifestations may lead to the development of more effective preventive and therapeutic options that can serve to delay long-term progression of these devastating disorders and improve the patients' quality of life. A better understanding of the pathophysiology and distinctive pathological features underlying the development of PS in neurodegenerative diseases may provide important insights into psychotic processes in general.

Effects of yokukansan on behavioral and psychological symptoms of vascular dementia: an open-label trial

Previous clinical trials suggest that the traditional Japanese medicine yokukansan has beneficial effects on the behavioral and psychological symptoms of dementia (BPSD). The present study was conducted to elucidate the efficacy of yokukansan on BPSD in patients with vascular dementia. Thirteen Japanese patients (9 men and 4 women) who were diagnosed as having vascular dementia (VaD) according to the diagnostic criteria of NINDS-AIREN were subjected to the open-label clinical trial in which yokukansan (7.5g/day) has been given for 4 weeks. Their mean age was 71.2±6.5 years. The BPSD was evaluated using the Neuropsychiatric Inventory (NPI), cognitive function was evaluated by the Mini-Mental State Examination (MMSE), the activities of daily living was evaluated by Barthel index (BI) and Disability Assessment for Dementia (DAD), and the extrapyramidal signs were evaluated by United Parkinson's Disease Rating Scale (UPDRS). The mean NPI was 33.0±17.3 and 23.6±13.9 for the baseline and after treatment, respectively. It was significantly improved after treatment (p<0.05). In the NPI-subcategories, there was a significant improvement in agitation and disinhibition after the treatment. There was no significant change in MMSE, BI, DAD or UPDRS before and after the treatment. There was no adverse effect during the treatment period. The present results suggest that yokukansan is beneficial for the treatment of BPSD in VaD patients.

AVPR1A and SLC6A4 polymorphisms in choral singers and non-musicians: a gene association study

Amateur choral singing is a common pastime and worthy of study, possibly conferring benefits to health and social behaviour. Participants might be expected to possess musical ability and share some behavioural characteristics. Polymorphisms in genes concerned with serotonergic neurotransmission are associated with both behaviour and musical aptitude. Those investigated previously include the variable number tandem repeats RS1, RS3 and AVR in the AVPR1A (arginine vasopressin receptor 1a) gene and STin2 in the SLC6A4 (solute carrier family 6 [neurotransmitter transporter, serotonin], member 4) gene, as well as the SLC6A4 promoter region polymorphism, 5-HTTLPR. We conducted a genetic association study on 523 participants to establish whether alleles at these polymorphisms occur more commonly in choral singers than in those not regularly participating in organised musical activity (non-musicians). We also analysed tagging single nucleotide polymorphisms (SNPs) for AVPR1A and SLC6A4 to determine whether other variants in these genes were associated with singer/non-musician status. At the STin2 polymorphism, overall association with singer/non-musician status was evident at P = 0.006. The 9-repeat (P = 0.04) and 12-repeat (P = 0.04) alleles were more common in singers and the 10-repeat allele less so (P = 0.009). Odds ratios were 0.73 (95% CI 0.57–0.94) for the 10-repeat allele and 2.47 (95% CI 0.88–6.94) for the rarer 9-repeat allele. No overall association was detected at P<0.05 between any other polymorphism and singer/non-musician status. Our null findings with respect to RS3, RS1 and AVR, polymorphisms associated with musical ability by other authors, suggest that choir membership may depend partly on factors other than musical ability. In a related musical project involving one participating choir, a new 40-part unaccompanied choral work, “Allele”, was composed and broadcast on national radio. In the piece, each singer's part incorporated their personal RS3 genotype.

Genetic determinants of aggression and impulsivity in humans

Human aggression/impulsivity-related traits have a complex background that is greatly influenced by genetic and non-genetic factors. The relationship between aggression and anxiety is regulated by highly conserved brain regions including amygdala, which controls neural circuits triggering defensive, aggressive, or avoidant behavioral models. The dysfunction of neural circuits responsible for emotional control was shown to represent an etiological factor of violent behavior. In addition to the amygdala, these circuits also involve the anterior cingulated cortex and regions of the prefrontal cortex. Excessive reactivity in the amygdala coupled with inadequate prefrontal regulation serves to increase the likelihood of aggressive behavior. Developmental alterations in prefrontal-subcortical circuitry as well as neuromodulatory and hormonal abnormality appear to play a role. Imbalance in testosterone/serotonin and testosterone/cortisol ratios (e.g., increased testosterone levels and reduced cortisol levels) increases the propensity toward aggression because of reduced activation of the neural circuitry of impulse control and self-regulation. Serotonin facilitates prefrontal inhibition, and thus insufficient serotonergic activity can enhance aggression. Genetic predisposition to aggression appears to be deeply affected by the polymorphic genetic variants of the serotoninergic system that influences serotonin levels in the central and peripheral nervous system, biological effects of this hormone, and rate of serotonin production, synaptic release and degradation. Among these variants, functional polymorphisms in the monoamine oxidase A (MAOA) and serotonin transporter (5-HTT) may be of particular importance due to the relationship between these polymorphic variants and anatomical changes in the limbic system of aggressive people. Furthermore, functional variants of MAOA and 5-HTT are capable of mediating the influence of environmental factors on aggression-related traits. In this review, we consider genetic determinants of human aggression, with special emphasis on genes involved in serotonin and dopamine metabolism and function.

Incidence and predictive factors of depressive symptoms in Alzheimer's disease: the REAL.FR study

BACKGROUND

Many patients develop psychiatric and behavioral disturbances in the course of Alzheimer's disease (AD). Among these disturbances, depressive symptoms are frequent and affect nearly 40% of patients. The natural history and course of such symptoms in AD, and in particular the predictive factors, are little known. We studied the incidence and risk factors for the development of the first depressive symptoms in AD.

DESIGN

Multicenter prospective study.

PARTICIPANTS

Three hundred twelve AD patients from the French Network on AD (REAL.FR) without depression and without antidepressant treatment at baseline were followed up and assessed every 6 months for 4 years. During follow-up, all events occurring between two visits were carefully recorded.

MEASUREMENTS

We used the Neuropsychiatric Inventory (NPI) for comprehensive evaluation of behavioral and psychological symptoms and depressive symptoms in particular. A multivariate analysis was performed using a backward stepwise Cox proportional hazards model.

RESULTS

The incidence of depressive symptoms was 17.45% person/years, 95%CI (13.88-21.02). Among non-time dependent variables, duration of disease (RR=0.51; 95%CI: 0.30-0.85, p=0.0102) and the number of comorbid conditions (RR=0.45; 95%CI: 0.24-0.83, p=0.0115) were protective factors against the development of depressive symptoms. Agitation/aggression (RR=1.96; 95%CI: 1.19-3.23, p=0.0078) and sleep disturbances (RR=2.65; 95%CI: 1.40-5.00, p=0.0026) were time-dependent variables predictive of depressive symptoms.

CONCLUSION

Better knowledge of predictive factors of mood disturbances in AD will enable clinicians to set up appropriate management of their patients. As published longitudinal studies are few, further works should be carried out to improve knowledge of the pattern and course of depression and depressive symptoms in AD.

Behavioural genetics of Alzheimer's disease: a comprehensive review

Behavioural and psychological symptoms of dementia (BPSD) are present in the course of the illness in up to 90% of patients with Alzheimer's disease (AD). They are the main source of caregiver burden and one of the major factors contributing to early institutionalization. The involvement of a genetic component in BPSD aetiology seems beyond controversy, though the exact significance of particular polymorphisms is uncertain in the majority of cases. Multiple genes have been assessed for their putative influence on BPSD risk. In this paper we review the behavioural genetics of AD, particularly the importance, with respect to BPSD risk, of genes coding for apolipoprotein E and proteins involved in the process of neurotransmission: serotonin receptors, serotonin transporter, COMT, MAO-A, tryptophan hydroxylase and dopamine receptors. A general conclusion is the striking inconsistency of the findings, unsurprising in the field of psychiatric genetics. The potential reasons for such discrepancy are exhaustively discussed.

Psychotic symptoms in a population-based sample of 85-year-old individuals with dementia

Psychotic symptoms are common in elderly persons with dementia. These symptoms affect a person's ability to function in daily life and put strain on the caregiver. Most studies focus on psychotic symptoms in clinical samples with Alzheimer disease (AD). Thus, their prevalence and relation with dementia subtype and severity in very old populations is unclear. We assessed a representative sample of 85-year-old individuals living in Gothenburg, Sweden (n = 494) using neuropsychiatric examinations, key informant interviews, and medical record reviews; 147 had dementia. Dementia and its severity were diagnosed in accordance with Diagnostic and Statistical Manual of Mental Disorders (Third Edition, Revision [DSM-III-R]) criteria. Alzheimer disease according to the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) criteria was diagnosed in 64 persons and vascular dementia (VaD) according to Erkinjuntti criteria was observed in 69. Fourteen had dementia due to other causes. Psychotic symptoms were classified according to DSM-III-R. The prevalence of psychotic symptoms in this very old population was 36% among AD cases compared to 54% in VaD cases (P = .04). Proportions with psychotic symptoms increased with increasing dementia severity in individuals with AD. No such association could be shown in those with VaD. This finding of a high proportion of psychotic symptoms also in individuals with mild severity of VaD should alert health professionals to evaluate dementia in very old patients who present with hallucinations or delusions.

Genetics of psychosis in Alzheimer's disease: a review

In and of itself, late-onset Alzheimer's disease (AD) can be a devastating illness. However, a sub-group of AD patients develop psychosis as the disease progresses. These patients have an added burden of greater cognitive impairment, higher rates of institutionalization, and higher mortality than AD patients without psychosis. While the etiopathogenesis such as psychosis in AD (AD+P) is not known, mounting evidence accrued over the past ten years indicates that AD+P represents a distinct phenotype with a genetic basis. Elucidating the genetic mechanism of AD+P is crucial if better pharmaceutical treatments are to be developed for these patients. The goal of this review is to summarize what is currently known regarding the genetic basis of psychosis in AD. Specific attention is given to familial aggregation and heritability, linkage to chromosomal loci, and associations of candidate genes of APOE and the monoamine neurotransmitter system.

Serotonin transporter triallelic genotype and response to citalopram and risperidone in dementia with behavioral symptoms

The risk/benefit ratio of pharmacotherapy for behavioral symptoms of dementia is questionable: second-generation antipsychotics are poorly tolerated, and the efficacy of alternative treatments, for example, selective serotonin-reuptake inhibitors (SSRIs), is uncertain. Biomarkers of treatment response may improve this risk/benefit ratio. The length polymorphism of the serotonin transporter promoter gene (5-HTTLPR/SLC6A4) may moderate tolerability of SSRIs and expression of behavioral symptoms in dementia. We assessed the effect of 5-HTTLPR on tolerability and efficacy of citalopram and risperidone in a 12-week randomized controlled trial, which included nondepressed patients with dementia hospitalized for behavioral or psychotic symptoms. Genotypes including the A/G polymorphism of the L allele (rs25531) were determined in 92 of 103 participants. We used pattern-mixture models to account for dropout. Low-expression alleles (S and Lg) predicted greater early and overall side effects of citalopram and early treatment discontinuation. These results remained unchanged after excluding African-American participants and in covariate analyses. Unexpectedly, low-expression alleles seemed to predict greater early side effects of risperidone (but not early discontinuation) and poorer early response of psychosis symptoms to risperidone. In conclusion, 5-HTTLPR may be a useful biomarker of SSRI intolerance in dementia. Our findings of intolerance of a second-generation antipsychotics and persistence of psychosis in patients with low-expression alleles needs to be replicated.

Serotonergic system genes in psychosis of Alzheimer dementia: meta-analysis

OBJECTIVE

The authors attempted to understand the role of two serotonin system genes, HTR2A and SLC6A4, on psychosis associated with Alzheimer dementia (AD).

METHOD

Relevant published studies were assessed, and their data were meta-analyzed to determine pooled odds ratios (ORs) that were assessed for heterogeneity. Additional robustness checks were performed to assess for publication bias and any undue influence from a single study. Finally, the number of studies required to invalidate positive findings was determined.

RESULTS

The C allele of HTR2A emerged as a significant risk factor for psychosis, with an allelic OR of 2.191 that increased to 5.143 for the homozygous CC genotype. The SLC6A4 polymorphism was not reliably associated with either psychosis or delusions.

CONCLUSIONS

The strong and robust positive association that was noted between the C allele of HTR2A and psychosis suggests that the HTR2A T102C polymorphism is a significant risk factor for psychosis of AD.

Management of agitation and aggression associated with Alzheimer disease

Agitation and aggression are frequently occurring and distressing behavioral and psychological symptoms of dementia (BPSD). These symptoms are disturbing for individuals with Alzheimer disease, commonly confer risk to the patient and others, and present a major management challenge for clinicians. The most widely prescribed pharmacological treatments for these symptoms-atypical antipsychotics-have a modest but significant beneficial effect in the short-term treatment (over 6-12 weeks) of aggression but limited benefits in longer term therapy. Benefits are less well established for other symptoms of agitation. In addition, concerns are growing over the potential for serious adverse outcomes with these treatments, including stroke and death. A detailed consideration of other pharmacological and nonpharmacological approaches to agitation and aggression in patients with Alzheimer disease is, therefore, imperative. This article reviews the increasing evidence in support of psychological interventions or alternative therapies (such as aromatherapy) as a first-line management strategy for agitation, as well as the potential pharmacological alternatives to atypical antipsychotics-preliminary evidence for memantine, carbamazepine, and citalopram is encouraging.

Effect of yokukansan on the behavioral and psychological symptoms of dementia in elderly patients with Alzheimer's disease

OBJECTIVE

The aim of this study was to investigate the effects of yokukansan (YKS) on the behavioral and psychological symptoms of dementia (BPSD) in elderly patients with Alzheimer's disease (AD).

METHODS

Fifteen patients with AD (mean age: 80.2+/-4.0 years) participated in the study. The Mini-Mental State Examination (MMSE) was used for the assessment of cognitive function. BPSD were evaluated using the Neuropsychiatric Inventory (NPI). The Barthel Index was used for the assessment for the activities of daily living (ADL). The treatment with YKS along with sulpiride, a dopamine D(2) selective antipsychotic, was performed for 12 weeks.

RESULTS

Fourteen patients completed the trial. After the 12 weeks of treatment with YKS, significant improvement of the mean NPI score was observed while no significant improvement was observed in the control group. The average dose of sulpiride at the end of the present study was less in the YKS group than in the control group. The MMSE results did not change either in the YKS group or in the control group. The Barthel Index did not significantly change either in the YKS group or in the control group. No serious adverse effects were noted.

CONCLUSIONS

Twelve weeks of the YKS treatment significantly improved BPSD with less antipsychotics in elderly patients with AD. The YKS treatment did not cause any cognitive decline or ADL decline and no serious adverse effects were noted. The present study suggests that YKS is beneficial for the treatment of BPSD and that it can possibly reduce the doses of antipsychotics required for the treatment of BPSD. Further studies with larger patient populations using a double-blind placebo-controlled design should be performed.

Effect of Yi-Gan San on psychiatric symptoms and sleep structure at patients with behavioral and psychological symptoms of dementia

OBJECTIVE

Recently, traditional herbal medicines have been reported to be effective for behavioral and psychological symptoms of dementia (BPSD). This study aims to examine the efficacy of Yi-Gan San (YGS) in the improvement of BPSD and sleep disorders in patients with dementia.

METHODS

Five patients (1 male and 4 female) with dementia in accordance with DSM-IV criteria were investigated. Participants were treated with YGS for 4 weeks. The Nursing Home version of Neuropsychiatric Inventory (NPI-NH) for the assessment of BPSD, the Mini-Mental State Examination (MMSE) for cognitive function, polysomnography for evaluation of sleep structure, and the Pittsburgh Sleep Quality Index for subjective sleep quality were carried out at baseline and at the end of treatment.

RESULTS

All patients completed the trial. Significant improvements in the total NPI-NH score (34.0+/-6.5 to 12.8+/-6.6) as well as delusions, hallucinations, agitation/aggression, anxiety, and irritability/lability, whereas MMSE scores were unchanged. PSG revealed increases in total sleep time, sleep efficiency, stage 2 sleep, and decreases in the number of arousals and periodic limb movements. Subjective sleep quality was also improved. No adverse effects were observed.

CONCLUSION

YGS was effective for BPSD and sleep disturbances, and well tolerated in patients with dementia. Further examinations using a double-blind placebo-controlled design are necessary.