INTRODUCTION:There has been considerable progress in identifying early cognitive and biomarker predictors of Alzheimer's disease (AD). Neuropsychiatric symptoms (NPS) are common in AD and appear to predict progression after the onset of mild cognitive impairment or dementia. OBJECTIVES:The objective of the study is to examine the relationship between NPS in clinically normal older adults and subsequent cognitive decline in a population-based sample. METHODS:The Cache County Study on Memory in Aging consists of a population-based sample of 5,092 older adults. We identified 470 clinically normal adults who were followed for an average period of 5.73 years. NPS were evaluated at the baseline clinical assessment using the Neuropsychiatric Inventory (NPI). NPI domains scores were quantified as the product of frequency X severity in individual NPI domains, and then summed for the NPI-Total. Neuropsychological measures were collected at baseline and at each subsequent follow-up wave. Linear mixed effects models assessed the association of NPI-Total, NPI-Depression, and NPI-Anxiety scores (obtained at baseline) on longitudinal change in neuropsychological performance, controlling for age, sex, and education. RESULTS:Baseline Neuropsychiatric Inventory (NPI)-Total score was associated with a more rapid rate of decline in word list memory, praxis recall, and animal fluency. Baseline NPI-Depression was not associated with later decline on any of the cognitive tests, while baseline NPI-Anxiety was associated with decline in Symbol Digit Modality. CONCLUSION:In conclusion, among clinically normal older adults derived from this population-based study, total burden of NPS was associated with longitudinal cognitive decline.

Objective: Prevalence of Alzheimer's disease (AD) is higher for women, possibly influenced by sex-dependent effects of the estrogen. We examined the association between estrogen and cognitive decline in over 2,000 older adult women in a 12-year population-based study in Cache County, Utah. Methods: The baseline sample included 2,114 women (mean age = 74.94 y, SD = 6.71) who were dementia-free at baseline and completed a women's health questionnaire, asking questions regarding reproductive history and hormone therapy (HT). Endogenous estrogen exposure (EEE) was calculated taking the reproductive window (age at menarche to age at menopause), adjusted for pregnancy and breastfeeding. HT variables included duration of use, HT type (unopposed; opposed), and time of HT initiation. A modified version of the Mini-Mental State Examination (3MS) was administered at four triennial waves to assess cognitive status. Linear mixed-effects models examined the relationship between estrogen exposure and 3MS score over time. Results: EEE was positively associated with cognitive status (β = 0.03, P = 0.054). In addition, longer duration of HT use was positively associated with cognitive status (β = 0.02, P = 0.046) and interacted with age; older women had greater benefit compared with younger women. The timing of HT initiation was significantly associated with 3MS (β = 0.55, P = 0.048), with higher scores for women who initiated HT within 5 years of menopause compared with those initiating HT 6-or-more years later. Conclusions: Our results suggest that longer EEE and HT use, especially in older women, are associated with higher cognitive status in late life.

Neurotrophins, including nerve-growth factor and brain-derived neurotrophic factor, have been implicated in Alzheimer's disease (AD). Associations between AD and neurotrophin signaling genes have been inconsistent, with few studies examining sex differences in risk. We examined four single-nucleotide polymorphisms (SNPs) involved in neurotrophin signaling (rs6265, rs56164415, rs2289656, rs2072446) and risk for AD by sex in a population-based sample of older adults. Three thousand four hundred and ninety-nine individuals without dementia at baseline [mean (standard deviation) age = 74.64 (6.84), 58% female] underwent dementia screening and assessment over four triennial waves. Cox regression was used to examine time to AD or right censoring for each SNP. Female carriers of the minor T allele for rs2072446 and rs56164415 had a 60% (hazard ratio [HR] = 1.60, 95% confidence interval [CI] = 1.02-2.51) and 93% (HR = 1.93, 95% CI = 1.30-2.84) higher hazard for AD, respectively, than male noncarriers of the T allele. Furthermore, male carriers of the T allele of rs2072446 had a 61% lower hazard (HR = 0.39, 95% CI = 0.14-1.06) than male noncarriers at trend-level significance (p = .07). The association between certain neurotrophin gene polymorphisms and AD differs by sex and may explain inconsistent findings in the literature.

OBJECTIVE-Closer caregiver-care recipient (CG-CR) relationships are associated with better cognitive and functional abilities, activities of daily living (in persons with dementia), and lower informal care costs. METHODS-Due to the difficulty in treating neuropsychiatric symptoms (NPSs) and their detrimental effects on caregivers and care recipients, we examined whether closeness of CG-CR relationships was associated with overall NPS severity or with specific NPS symptom domains in care recipients. In a longitudinal population-based study in Cache County, Utah, the 12-item Neuropsychiatric Inventory (NPI-12) was assessed in 300 CG-CR dyads. Caregivers reported current relationship closeness using the Whitlatch Relationship Closeness Scale. Linear mixed models examined associations between CG-CR closeness and NPI-12 total score or selected symptom domains over time (observation period: 2002-2012). RESULTS-In unadjusted linear mixed models, higher closeness scores were associated with a five-point lower NPI-12 score and a one-point lesser increase in NPI-12 per year. NPI scores also showed lower affective cluster scores (two points) and lesser increase in psychosis cluster

Objectives To examine the prevalence of neuropsychiatric symptoms (NPS) and cognitive correlates in severe dementia. Methods A population‐based sample of 56 individuals with severe dementia (85.7% Alzheimer's type; 67.9% female) were assessed with the Severe Cognitive Impairment Profile (SCIP) and the Neuropsychiatric Inventory (NPI). Descriptive statistics displayed the frequency of NPS and bivariate and multiple regression analyses examined the associations between cognitive domains on the SCIP and NPS total, domain, and cluster scores. Results NPS were common in severe dementia with 98% of the sample exhibiting at least one symptom. Most common were delusions, apathy, agitation/aggression, and aberrant motor behavior, affecting 50% or more of participants. SCIP comportment was significantly associated with NPI total score and apathy (r = −.350 and −.292, respectively). All SCIP domains except for arithmetic, visuospatial, comportment, and motor behavior were significantly associated with agitation/aggression (r = −.285 to −.350). These associations remained in individual multiple regression models. Conclusion In severe dementia, impairment in specific cognitive domains was associated with more severe NPS. Environmental manipulations to reduce processing demands in persons with severe dementia may be a useful strategy to target agitation and aggressive behaviors.