Age of onset for increased dose-adjusted serum concentrations of antidepressants and association with sex and genotype: An observational study of 34,777 individuals.

PURPOSE: The aim of this study was to examine the age of onset for increased dose-adjusted serum concentrations (C/D ratio) of common antidepressant drugs and to explore the potential association with sex and CYP2C19/CYP2D6 genotype. METHODS: Serum concentrations and prescribed daily doses for citalopram, escitalopram, sertraline, venlafaxine and mirtazapine, and CYP genotypes, were obtained from a therapeutic drug monitoring (TDM) service. Segmented linear regression analysis was used to examine the relationship between age and antidepressant log C/D ratio in (i) all individuals, (ii) men and women, and (iii) CYP2D6/CYP2C19 normal metabolizers (NMs) and CYP2D6/CYP2C19 intermediate or poor metabolizers (IMs/PMs). RESULTS: A total of 34,777 individuals were included in the study; CYP genotype was available for 21.3%. An increase in C/D ratio started at 44‒55 years of age. Thereafter, the increase progressed more rapidly for citalopram and escitalopram than for venlafaxine and mirtazapine. A doubled C/D ratio was estimated to occur at 79 (citalopram), 81 (escitalopram), 86 (venlafaxine), and 90 years (mirtazapine). For sertraline, only modest changes in C/D ratio were observed. For escitalopram and venlafaxine, the observed increase in C/D ratio started earlier in women than in men. The results regarding CYP genotype were inconclusive. CONCLUSION: The age-related increase in C/D ratio starts in middle-aged adults and progresses up to more than twofold higher C/D ratio in the oldest old. Sertraline seems to be less prone to age-related changes in C/D ratio than the other antidepressants.

Longitudinal cerebrospinal fluid measurements show glial hypo- and hyperactivation in predementia Alzheimer's disease.

BACKGROUND: Brain innate immune activation is associated with Alzheimer's disease (AD), but degrees of activation may vary between disease stages. Thus, brain innate immune activation must be assessed in longitudinal clinical studies that include biomarker negative healthy controls and cases with established AD pathology. Here, we employ longitudinally sampled cerebrospinal fluid (CSF) core AD, immune activation and glial biomarkers to investigate early (predementia stage) innate immune activation levels and biomarker profiles. METHODS: We included non-demented cases from a longitudinal observational cohort study, with CSF samples available at baseline (n = 535) and follow-up (n = 213), between 1 and 6 years from baseline (mean 2.8 years). We measured Aß42/40 ratio, p-tau181, and total-tau to determine Ab (A+), tau-tangle pathology (T+), and neurodegeneration (N+), respectively. We classified individuals into these groups: A-/T-/N-, A+/T-/N-, A+/T+ or N+, or A-/T+ or N+. Using linear and mixed linear regression, we compared levels of CSF sTREM2, YKL-40, clusterin, fractalkine, MCP-1, IL-6, IL-1, IL-18, and IFN-γ both cross-sectionally and longitudinally between groups. A post hoc analysis was also performed to assess biomarker differences between cognitively healthy and impaired individuals in the A+/T+ or N+ group. RESULTS: Cross-sectionally, CSF sTREM2, YKL-40, clusterin and fractalkine were higher only in groups with tau pathology, independent of amyloidosis (p < 0.001, A+/T+ or N+ and A-/T+ or N+, compared to A-/T-/N-). No significant group differences were observed for the cytokines CSF MCP-1, IL-6, IL-10, IL18 or IFN-γ. Longitudinally, CSF YKL-40, fractalkine and IFN-γ were all significantly lower in stable A+/T-/N- cases (all p < 0.05). CSF sTREM2, YKL-40, clusterin, fractalkine (p < 0.001) and MCP-1 (p < 0.05) were all higher in T or N+, with or without amyloidosis at baseline, but remained stable over time. High CSF sTREM2 was associated with preserved cognitive function within the A+/T+ or N+ group, relative to the cognitively impaired with the same A/T/N biomarker profile (p < 0.01). CONCLUSIONS: Immune hypoactivation and reduced neuron-microglia communication are observed in isolated amyloidosis while activation and increased fractalkine accompanies tau pathology in predementia AD. Glial hypo- and hyperactivation through the predementia AD continuum suggests altered glial interaction with Ab and tau pathology, and may necessitate differential treatments, depending on the stage and patient-specific activation patterns.

Dementia with Lewy bodies: Impact of co-pathologies and implications for clinical trial design.

Dementia with Lewy bodies (DLB) is clinically defined by the presence of visual hallucinations, fluctuations, rapid eye movement (REM) sleep behavioral disorder, and parkinsonism. Neuropathologically, it is characterized by the presence of Lewy pathology. However, neuropathological studies have demonstrated the high prevalence of coexistent Alzheimer's disease, TAR DNA-binding protein 43 (TDP-43), and cerebrovascular pathologic cases. Due to their high prevalence and clinical impact on DLB individuals, clinical trials should account for these co-pathologies in their design and selection and the interpretation of biomarkers values and outcomes. Here we discuss the frequency of the different co-pathologies in DLB and their cross-sectional and longitudinal clinical impact. We then evaluate the utility and possible applications of disease-specific and disease-nonspecific biomarkers and how co-pathologies can impact these biomarkers. We propose a framework for integrating multi-modal biomarker fingerprints and step-wise selection and assessment of DLB individuals for clinical trials, monitoring target engagement, and interpreting outcomes in the setting of co-pathologies.

Genome-wide association identifies the first risk loci for psychosis in Alzheimer disease.

Psychotic symptoms, defined as the occurrence of delusions or hallucinations, are frequent in Alzheimer disease (AD with psychosis, AD + P). AD + P affects ~50% of individuals with AD, identifies a subgroup with poor outcomes, and is associated with a greater degree of cognitive impairment and depressive symptoms, compared to subjects without psychosis (AD - P). Although the estimated heritability of AD + P is 61%, genetic sources of risk are unknown. We report a genome-wide meta-analysis of 12,317 AD subjects, 5445 AD + P. Results showed common genetic variation accounted for a significant portion of heritability. Two loci, one in ENPP6 (rs9994623, O.R. (95%CI) 1.16 (1.10, 1.22), p = 1.26 × 10-8) and one spanning the 3'-UTR of an alternatively spliced transcript of SUMF1 (rs201109606, O.R. 0.65 (0.56-0.76), p = 3.24 × 10-8), had genome-wide significant associations with AD + P. Gene-based analysis identified a significant association with APOE, due to the APOE risk haplotype ε4. AD + P demonstrated negative genetic correlations with cognitive and educational attainment and positive genetic correlation with depressive symptoms. We previously observed a negative genetic correlation with schizophrenia; instead, we now found a stronger negative correlation with the related phenotype of bipolar disorder. Analysis of polygenic risk scores supported this genetic correlation and documented a positive genetic correlation with risk variation for AD, beyond the effect of ε4. We also document a small set of SNPs likely to affect risk for AD + P and AD or schizophrenia. These findings provide the first unbiased identification of the association of psychosis in AD with common genetic variation and provide insights into its genetic architecture.

The association between aspects of carer distress and time until nursing home admission in persons with Alzheimer's disease and dementia with Lewy bodies.

OBJECTIVE: The aim of this study was to explore the association between specific aspects of carer distress and time until nursing home admission (NHA) in people with mild dementia. DESIGN: Prospective cohort study. SETTING: Participants were recruited from the Dementia Study of Western Norway (DemVest). PARTICIPANTS: This study included 107 participants admitted to a nursing home who were diagnosed with Alzheimer's disease (AD, n = 64) and dementia with Lewy bodies (DLB, n = 43) and their primary carers. MEASUREMENTS: The Relative Stress Scale (RSS) was used to assess the level of reported distress in carers. Adjusted partial least square (PLS) prediction analysis of baseline items of the RSS was used to study the associations between individual items of the RSS and time until NHA. RESULTS: Carer distress is an important contributor to early NHA, explaining 19.3% of the total variance of time until NHA in the model without covariates. In the adjusted PLS model, the most important RSS predictors of time until NHA were feeling frustrated (estimate = -137; CI, -209, -64.5), having limitations on social life (estimate = -118; CI, -172, -64), not being able to get away on vacation (estimate -116; CI, -158.3, -73.7), and feeling unable to cope with the situation (estimate = -63; CI, -122.6, -3.4). CONCLUSIONS: Preservation of the informal care capacity represents important steps for improving the management of resources in dementia care. This study identifies aspects of carer distress associated with a shorter time until NHA. Looking beyond the sum score of the RSS helps promote the development of flexible and tailored interventions and perhaps delay NHA.

Factors associated with self-rated health in a Norwegian population of older people participating in a preventive home visit program: a cross-sectional study.

BACKGROUND: Assessing self-rated health by preventive home visits of older people can provide information about the person's well-being, quality of life and risk of developing illness. The aim of this study was to examine associations between self-rated health and factors related to demographics, lifestyle, health conditions and medical diagnoses by older people participating in a preventive home visit program. METHODS: A cross-sectional study including 233 participants (age 75-79) from three municipalities of Western Norway was conducted. Data were collected through preventive home visits performed by six nurses, using a questionnaire including self-rated health assessment and questions and tests related to demographics (e.g. education and housing), lifestyle (e.g. social activities, alcohol and smoking), health conditions (e.g. sensory impairment, pain and limited by disease) and medical diagnoses. Descriptive and inferential statistics including linear block-wise regression model were applied. RESULTS: The block-wise regression model showed that the variables Limited by disease and Pain were negatively associated with self-rated health and Use internet was positively associated. The model had a R2 0.432. The variable that contributed to largest change in the model was Limited by disease (R2 Change; 0.297, p-value< 0.001). CONCLUSIONS: In the present study, being limited by disease and pain were strongly associated with poor self-rated health, indicating that these are important factors to assess during a preventive home visit. Also, digital competence (Use internet) was associated with a better self-rated health, suggesting that it could be useful to ask, inform and motivate for the use of digital tools that may compensate for or improve social support, social contact and access to health -related information.

The association between specific neuropsychiatric disturbances in people with Alzheimer's disease and dementia with Lewy bodies and carer distress.

OBJECTIVE: Neuropsychiatric symptoms (NPSs) are identified as important care-recipient variables in terms of the impact on carer distress. The aim of this study was to determine whether specific neuropsychiatric disturbances in people with Alzheimer disease (AD) and dementia with Lewy bodies (DLB) differentially impact carer distress. METHODS: This was a cross-sectional study of people diagnosed with AD and DLB and their primary carers. The Relatives' Stress Scale (RSS) was used to assess the level of reported distress in carers, and the Neuropsychiatric Inventory (NPI) was used to assess NPSs. The effect of NPSs on carer distress was analyzed using correlation analysis and partial least squares regression. RESULTS: This study included 159 participants diagnosed with AD (n = 97) and DLB (n = 62) and their primary carers (spouses and adult children). The majority of people diagnosed with dementia were women (64.2%), with a mean age of 75.9 years (SD, 7.4) and a mean Mini-Mental State Examination (MMSE) score of 23.5 (SD, 2.9). The main analysis identified apathy as the most important NPS contributing to carer distress. Compared with AD, the explained variance in the DLB group was higher (r2  = 37.3 vs r2  = 53.7). In addition, more NPSs were considered clinically important in the DLB group. CONCLUSION: The findings of this study identify apathy as the most important NPS contributing to carer distress among carers of people with AD and DLB. These findings help us identify the support needs of families dealing with dementia.

Patterns of carer distress over time in mild dementia.

OBJECTIVE: To study the level of carer reported distress in mild dementia, over a 3-year period. METHODS: This study is part of the Norwegian DemVest-study and utilises data from carers of people with mild dementia (n = 223). Those diagnosed with dementia with Lewy bodies (DLB, n = 63) and Alzheimer's disease (AD, n = 97) were included together with other dementia types (n = 63). The Relatives' Stress Scale was used to assess the level of reported distress in carers. Descriptive and a linear mixed effects models including diagnosis, time, and the interaction between time and diagnosis were performed. RESULTS: Carer distress in mild dementia increased significantly over time (P = 0.011), particularly from baseline until 2 (P = 0.001) years follow-up. Carer distress in people caring for those with AD increased significantly, from baseline until 2 (P = 0.047) and 3 (P = 0.019) years follow-up. Distress in carers of people with DLB was high at baseline and remained relatively stable across the 3-year period. However, admission to a nursing home during the first year of follow-up was associated with a significantly lower reported carer distress in those caring for a person with DLB (P = 0.002), compared with those caring for a person with DLB living at home. CONCLUSION: Being a carer to a person with mild dementia is associated with increasing distress. However, the burden of distress changes with the diagnosis, time, and situation, which highlights the dynamic nature of the caring role. Findings have important implications for health services for people diagnosed with mild dementia and their carers.

Potentially inappropriate medications and drug-drug interactions in home-dwelling people with mild dementia.

OBJECTIVES: The objectives of this study were to describe the use of psychotropic drugs among home-dwelling people with mild dementia, to identify potentially inappropriate medications (PIM) and drug-drug interactions (DDI), and to analyze potential variables associated with having PIM and DDI. METHODS: Patients (n = 251) with a first-time diagnosis of mild dementia (defined as a mini-mental state examination score >20) were included from outpatient clinics. Prevalence of psychotropic drug use, polypharmacy, and psychotropic polypharmacy were investigated. The prevalence of PIM and DDI were defined using the Norwegian general practice criteria and an interactions database, respectively. Variables associated with having PIM and DDI were assessed using a multivariable logistic regression analysis adjusting for relevant demographic and clinical variables. RESULTS: Almost 96% of the patients used one or more medications. Polypharmacy was found in 45% of the patients, and nearly 70% of the patients were using one or more psychotropic drugs. Psychotropic polypharmacy was found in seven patients. PIM were identified in 35 patients (14%), while only four severe DDI were found. Female sex and number of medications were significantly associated with having PIM, whereas only number of medications was significantly associated with having DDI. CONCLUSION: Few patients had PIM or severe DDI, indicating that the quality of prescribing was acceptable. However, psychotropic drug use was common in home-dwelling people with mild dementia despite limited evidence of benefit in dementia. More knowledge is needed about the potential risks associated with psychotropic drug use and having PIM and DDI in people with mild dementia. Copyright © 2016 John Wiley & Sons, Ltd.

The relationship of specific items on the Neuropsychiatric Inventory to caregiver burden in dementia: a systematic review.

OBJECTIVE: Neuropsychiatric symptoms (NPSs) are common in dementia, and they have been identified as important care-recipient variables in terms of their impact on caregiver burden. The aim of this review was to describe how individual NPSs in dementia, assessed using the Neuropsychiatric Inventory, are associated with caregiver burden. METHODS: We performed a systematic review of English language, peer-reviewed articles retrieved from MEDLINE, PSYCINFO, and EMBASE. RESULTS: A total of 13 studies met the inclusion criteria. Four studies examined the association between individual NPSs and caregiver burden using the Spearman rank correlation test, while three used Pearson's correlation test. Of the remaining studies, five used multiple regression analyses and one the chi-squared test. The majority of included studies did not differentiate between dementia subtypes in the analysis or mainly included only caregivers of people with Alzheimer's disease. The Clinical Dementia Rating score and mean Mini-Mental State Examination score indicate mild to moderate dementia. The majority of caregivers were women, most of whom were children (53.8%) or spouses (36%). The data indicated that irritability, followed by agitation, sleep disturbances, anxiety, apathy, and delusion seem to impact caregiver burden the most. CONCLUSION: Our principal finding is that irritability, agitation, sleep disturbances, anxiety, apathy, and delusion seem to exert the most impact on caregiver burden. Heterogeneity in the measures and statistical analyses used, however, makes it difficult to make conclusive interpretations. Future research in this field would benefit from standardization of the scientific methodology in use. Copyright © 2017 John Wiley & Sons, Ltd.

Polygenic Overlap Between C-Reactive Protein, Plasma Lipids, and Alzheimer Disease.

BACKGROUND: Epidemiological findings suggest a relationship between Alzheimer disease (AD), inflammation, and dyslipidemia, although the nature of this relationship is not well understood. We investigated whether this phenotypic association arises from a shared genetic basis. METHODS AND RESULTS: Using summary statistics (P values and odds ratios) from genome-wide association studies of >200 000 individuals, we investigated overlap in single-nucleotide polymorphisms associated with clinically diagnosed AD and C-reactive protein (CRP), triglycerides, and high- and low-density lipoprotein levels. We found up to 50-fold enrichment of AD single-nucleotide polymorphisms for different levels of association with C-reactive protein, low-density lipoprotein, high-density lipoprotein, and triglyceride single-nucleotide polymorphisms using a false discovery rate threshold <0.05. By conditioning on polymorphisms associated with the 4 phenotypes, we identified 55 loci associated with increased AD risk. We then conducted a meta-analysis of these 55 variants across 4 independent AD cohorts (total: n=29 054 AD cases and 114 824 healthy controls) and discovered 2 genome-wide significant variants on chromosome 4 (rs13113697; closest gene, HS3ST1; odds ratio=1.07; 95% confidence interval=1.05-1.11; P=2.86×10(-8)) and chromosome 10 (rs7920721; closest gene, ECHDC3; odds ratio=1.07; 95% confidence interval=1.04-1.11; P=3.38×10(-8)). We also found that gene expression of HS3ST1 and ECHDC3 was altered in AD brains compared with control brains. CONCLUSIONS: We demonstrate genetic overlap between AD, C-reactive protein, and plasma lipids. By conditioning on the genetic association with the cardiovascular phenotypes, we identify novel AD susceptibility loci, including 2 genome-wide significant variants conferring increased risk for AD.

Caregiver burden in family carers of people with dementia with Lewy bodies and Alzheimer's disease.

OBJECTIVE: To characterise the differences in caregiver distress between carers of people diagnosed with dementia with Lewy bodies (DLB) and people with Alzheimer's disease (AD), with a view to differentiating and improving support for caregivers. METHODS: This study is a part of two larger Norwegian studies, DemVest (n = 265) and The Norwegian Dementia Register (n = 2220), with data from caregivers and people diagnosed with AD (n = 100) and DLB (n = 86) between 2005 and 2013. The average age was 74.9 years (SD = 7.8). Caregiver distress was rated by the Relative Stress Scale. Diagnosis of the person receiving care was based on a comprehensive standardised assessment program (International Classification of Diseases, Revision 10 or Diagnostic and Statistical Manual for Mental Disorders, fourth edition). Additional data collected from people receiving care were neuropsychiatric symptoms, comorbidity and activities of daily living (ADL) score. Linear regression analyses were applied, first unadjusted and then in stepwise-adjusts in addition to descriptive analyses. RESULTS: Caregivers to people with AD (20.2%) and 40% of caregivers for people with DLB experienced moderate or high caregiver burden with an increased risk of psychiatric disorders in the early stage of dementia. High Relative Stress Scale (RSS) total scores in caregivers was significantly associated with neuropsychiatric symptoms (Neuropsychiatric Inventory, p = 0.004) and also with impaired ADL functioning (Rapid Disability Rating Scale-2, p < 0.0005). CONCLUSION: Caregiver distress differed (RSS total, p = 0.005) between people caring for someone with AD (15.0) and those caring for someone with DLB (19.9). These findings have direct implications for the needs and resources that could be available for these individuals and indicate the need for further research into caregiver burden in carers to people with DLB. Copyright © 2016 John Wiley & Sons, Ltd. ETHICS AND DISSEMINATION: Cohorts were ethically approved by the Regional Ethics Committee for Medical Research Ethics in Eastern and Western Norway.

Higher Frequency and Complexity of Sleep Disturbances in Dementia with Lewy Bodies as Compared to Alzheimer's Disease.

BACKGROUND: Sleep disturbances (SDs) are common in patients with all forms of dementia. However, most studies focus on Alzheimer's disease (AD) and less is known about the prevalence and characteristics of SD in dementia with Lewy bodies (DLB). OBJECTIVE: The aims of this cross-sectional study were: (1) to examine the frequency of SD in DLB versus AD; (2) to compare patients with and without SD with regard to relevant clinical variables, and (3) to investigate the associations between SD and medication use. METHODS: Patients with a first-time diagnosis of probable or possible DLB or AD were selected from the Dementia Study of Western Norway and recruited from clinics for old age psychiatry from 2010 until the end of 2013. RESULTS: In all, 123 (55.7%) subjects with dementia suffered from at least one SD. Insomnia was present in 77 (34.8%), and 34 (20.7%) patients had probable REM-sleep behaviour disorder (RBD). All SDs were also significantly more frequent in patients with DLB than in AD, and DLB patients also more often had several co-occurring SDs. The presence of any SD was associated with more neuropsychiatric symptoms, higher morbidity, more parkinsonian symptoms and excessive daytime sleepiness. Antiparkinsonian medication was used more often in RBD, restless leg syndrome (RLS) and periodic limb movements, and benzodiazepines were also common in RLS. CONCLUSIONS: Sleep problems are more common in DLB patients compared to AD, and are associated with more clinical impairment. DLB patients frequently have several sleep problems occurring simultaneously, which suggests a need for screening and accurate assessment of sleep in DLB.

Apolipoprotein E ε2 genotype delays onset of dementia with Lewy bodies in a Norwegian cohort.

BACKGROUND: Results conflict concerning the relevance of APOE alleles on the development of dementia with Lewy bodies (DLB), though they are well established in connection with Alzheimer's disease (AD). The role of APOE alleles in a Norwegian cohort of patients with DLB was therefore examined compared with patients with AD and healthy control individuals. METHODS: The study included 156 patients with DLB diagnosed according to the consensus criteria guidelines, 519 patients diagnosed with AD according to the National Institute of Neurological and Communicative Diseases and Stroke/Alzheimer's Disease and Related Disorders Association (NINCDS/ARDRA) criteria and 643 healthy elderly volunteers. Patients were recruited through hospitals, outpatient clinics, nursing homes or from local care authorities in central and south-western parts of Norway. Healthy individuals were recruited from caregivers and societies for retired people. RESULTS: Subjects carrying an APOE ε2 allele had a reduced risk for developing DLB (OR 0.4, CI 0.3 to 0.8, p=0.004), and the onset of disease was delayed by 4 years (p=0.01, Mann-Whitney U test). Conversely, the APOE ε4 allele increased the risk for development of DLB (OR 5.9, CI 2.7 to 13.0, p<0.0005 for homozygotes). Similar results were found for patients with AD regarding the effect of APOE ε2, though the protective effect appeared to be slightly less pronounced than in DLB. This study is one of the largest regarding DLB and APOE to date. CONCLUSION: The results indicate that APOE ε2, a protective factor in AD, has a clear beneficial effect on the development of DLB also.

The use and costs of formal care in newly diagnosed dementia: a three-year prospective follow-up study.

OBJECTIVE: To investigate the use of formal care during the first three years after diagnosis of mild dementia and identify cost-predicting factors. DESIGN: Prospective longitudinal study over three years. SETTING: An incidence-based bottom-up cost-of-illness study where information about formal health care services was drawn from the municipalities' registers during the first three years after the diagnosis of mild dementia. PARTICIPANTS: 109 patients with mild dementia at baseline, diagnosed according to consensus criteria based on standardized assessments. MEASUREMENT: The use of formal care as registered by the municipalities' registration systems. Costs were estimated by applying unit costs, including municipal expenses and out-of-pocket contributions. Clinical data were collected at baseline to identify cost-predicting factors. RESULTS: Costs for formal care were increasing from € 535 per month of survival (MOS) at baseline to € 3,611 per MOS during the third year, with a mean of € 2,420 during the whole observation period. The major cost driver (74%) was institutional care. The costs for people with dementia with Lewy bodies (€ 3,247 per MOS) were significantly higher than for people with Alzheimer disease (€ 1,855 per MOS). The most important cost-predicting factors we identified were the living situation, a diagnosis of non-Alzheimer disease, comorbidity, and daily living functioning. The use of cholinesterase inhibitors was related to lower costs. CONCLUSION: Formal care costs increased significantly over time with institutional care being the heaviest cost driver. Studies with longer observation periods will be necessary to evaluate the complete socioeconomic impact of the course of dementia.

Long-term mortality in a cohort of home-dwelling elderly with mild Alzheimer's disease and Lewy body dementia.

OBJECTIVE: To study mortality in subjects with mild dementia in Norway with a special focus on patients with Lewy body dementia (LBD) compared to Alzheimer's disease (AD). METHODS: All referrals of mild dementia patients to dementia clinics in western Norway from March 2005 to March 2007 were included and followed until December 2012. Diagnoses were based on a comprehensive standardized assessment program. RESULTS: Of 209 patients, 137 (66%) had AD and 53 (25%) had LBD. Dementia was associated with increased mortality (standardized mortality ratio = 1.8, AD 1.5, LBD 2.6). The median survival time was 6.2 years (95% CI 5.4-6.9). Predictors of mortality were age at diagnosis (HR 1.1 per year) and LBD diagnosis (HR 2.4). CONCLUSION: Dementia patients had an increased mortality, particularly those with LBD.

Time until nursing home admission in people with mild dementia: comparison of dementia with Lewy bodies and Alzheimer's dementia.

OBJECTIVE: We studied time until nursing home admission (NHA) in mild dementia and predictors for NHA in people with Dementia with Lewy bodies (DLB) and how it compares to Alzheimer's dementia (AD). METHODS: Kaplan-Meier survival analysis and Cox proportional hazards were applied. RESULTS: Median time until NHA was 1114 days (95% confidence interval [CI] [932, 1296]). In DLB median time until NHA was 663 days [472, 998]) as compared with 1336 days (1068, 1606) in AD, p < 0.0005. Predictors of shorter time to NHA in the DLB and AD groups in unadjusted analyses were a DLB diagnosis, the use of antipsychotic medication, more advanced age, longer duration of dementia symptoms prior to diagnosis, living alone, higher reported caregiver distress, and more neuropsychiatric symptoms. The use of cholinesterase inhibitors was associated with halved risk of NHA in the combined DLB/AD group in the unadjusted Cox regression. In adjusted Cox regression in the DLB group, we found the use of cholinesterase inhibitors to be associated with reduced risk of NHA (HR = 0.24) and the use of antipsychotic medication to be associated with increased risk of NHA (HR = 37) during the study period. CONCLUSION: Patients diagnosed with DLB had nearly 2 years shorter time to NHA than those diagnosed with AD. In the DLB group, the use of cholinesterase inhibitors was associated with reduced and the use of antipsychotics with increased risk of NHA. Future studies should explore whether better identification and management of the variety of clinical problems in patients diagnosed with DLB can delay NHA.

Depressive Symptoms Are Not Associated with Predementia Cerebrospinal Fluid Amyloid Pathology.

Introduction: Depressive symptoms are associated with Alzheimer's disease (AD), but their neurobiological and neuropsychological correlates remain poorly understood. We investigate if depressive symptoms are associated with amyloid (Aß) pathology and cognition in predementia AD. Methods: We included subjective cognitive decline (SCD, n = 160) and mild cognitive impairment (MCI, n = 192) from the dementia disease initiation cohort. Depressive symptoms were assessed using the Geriatric Depression Scale (GDS-15). Aß pathology was determined using cerebrospinal fluid (CSF) Aß42/40 ratio. Associations between depressive symptoms and cognition were assessed with logistic regression. Results: Only the Aß negative MCI group (MCI-Aß-) was associated with depressive symptoms (odds ratio [OR] = 2.65, p = 0.005). Depressive symptoms were associated with worse memory in MCI-Aß- (OR = 0.94, p = 0.039), but with better performance in MCI-Aß+ (OR = 1.103, p = 0.001). Conclusion: Our results suggest that depressive symptoms in MCI are neither associated with Aß pathology, nor AD-associated memory impairment. However, memory impairment in non-AD MCI may relate to depressive symptoms.

Cerebrospinal fluid neurofilament light chain mediates age-associated lower learning and memory in healthy adults.

Multiple cognitive domains, including learning, memory, and psychomotor speed, show significant reductions with age. Likewise, several cerebrospinal fluid (CSF) neurodegenerative biomarkers, including total tau (t-tau, a marker of neuronal body injury) and neurofilament light chain (NfL, a marker of axonal injury) show age-related increases in normal aging. In the current study, we aimed to investigate whether the age-effect within different cognitive domains was mediated by age-associated CSF markers for neurodegenerative changes. We fitted 10 mediation models using structural equation modeling to investigate this in a cohort of 137 healthy adults, aged 40-80 years, from the Norwegian Dementia Disease Initiation (DDI) study. Here, t-tau and NfL were defined as mediators between age and different cognitive tests. The models showed that NfL mediated the age-effect for CERAD learning and memory recall (learning: ß = -0.395, p < 0.05; recall: ß = -0.261, p < 0.01). No such effect was found in the other models. Our findings suggest that the age-related lower performance in verbal learning and memory may be linked to NfL-associated neurodegenerative changes in cognitively healthy adults.