A comparison of confidence distribution approaches for rare event meta-analysis.

Meta-analysis of rare event data has recently received increasing attention due to the challenging issues rare events pose to traditional meta-analytic methods. One specific way to combine information and analyze rare event meta-analysis data utilizes confidence distributions (CDs). While several CD methods exist, no comparisons have been made to determine which method is best suited for homogeneous or heterogeneous meta-analyses with rare events. In this article, we review several CD methods: Fisher's classic P-value combination method, one that combines P-value functions, another that combines confidence intervals, and one that combines confidence log-likelihood functions. We compare these CD approaches, and we propose and compare variations of these methods to determine which method produces reliable results for homogeneous or heterogeneous rare event meta-analyses. We find that for homogeneous rare event data, most CD methods perform very well. On the other hand, for heterogeneous rare event data, there is a clear split in performance between some CD methods, with some performing very poorly and others performing reasonably well.

A permutation-based approach for heterogeneous meta-analyses of rare events.

The increasingly widespread use of meta-analysis has led to growing interest in meta-analytic methods for rare events and sparse data. Conventional approaches tend to perform very poorly in such settings. Recent work in this area has provided options for sparse data, but these are still often hampered when heterogeneity across the available studies differs based on treatment group. We propose a permutation-based approach based on conditional logistic regression that accommodates this common contingency, providing more reliable statistical tests when such patterns of heterogeneity are observed. We find that commonly used methods can yield highly inflated Type I error rates, low confidence interval coverage, and bias when events are rare and non-negligible heterogeneity is present. Our method often produces much lower Type I error rates and higher confidence interval coverage than traditional methods in these circumstances. We illustrate the utility of our method by comparing it to several other methods via a simulation study and analyzing an example data set, which assess the use of antibiotics to prevent acute rheumatic fever.

Family-based tests for associating haplotypes with general phenotype data: Improving the FBAT-haplotype algorithm.

For family-based association studies, Horvath et al. proposed an algorithm for the association analysis between haplotypes and arbitrary phenotypes when the phase of the haplotypes is unknown, that is, genotype data is given. Their approach to haplotype analysis maintains the original features of the TDT/FBAT-approach, that is, complete robustness against genetic confounding and misspecification of the phenotype. The algorithm has been implemented in the FBAT and PBAT software package and has been used in numerous substantive manuscripts. Here, we propose a simplification of the original algorithm that maintains the original approach but reduces the computational burden of the approach substantially and gives valuable insights regarding the conditional distribution. With the modified algorithm, the application to whole-genome sequencing (WGS) studies becomes feasible; for example, in sliding window approaches or spatial-clustering approaches. The reduction of the computational burden that our modification provides is especially dramatic when both parental genotypes are missing. For example, for eight variants and 441 nuclear families with mostly offspring-only families, in a WGS study at the APOE locus, the running time decreased from approximately 21 hr for the original algorithm to 0.11 sec after our modification.

Nutritional Status is Associated With Severe Dementia and Mortality: The Cache County Dementia Progression Study.

PURPOSE: Studies have reported faster cognitive/functional decline in persons with dementia (PWD) with malnutrition. We investigated whether baseline nutritional status predicted severe dementia and mortality in a population-based sample. PATIENTS: A maximum of 300 PWD were assessed annually for up to 8.6 years. METHODS: Nutritional status was assessed using a modified Mini-Nutritional Assessment (mMNA). Severe dementia was defined as: "severe" rating on the Clinical Dementia Rating or Mini-Mental State Examination score ≤10. Using Cox proportional hazards models, we examined the association between baseline mMNA score (or its subcomponents) with each outcome. Covariates included demographics; dementia onset age, type, and duration; APOE genotype; and residency with caregiver. RESULTS: Compared with "well-nourished," "malnourished" PWD had 3-4 times the hazard of severe dementia [hazard ratio (HR), 4.31; P=0.014] and death (HR, 3.04; P<0.001). Those "at risk for malnutrition" had twice the hazard of severe dementia (HR, 1.98; P=0.064) and 1.5 times the hazard of death (HR, 1.46; P=0.015). mMNA subcomponents of food group intake, weight loss, body mass index, mobility, health status, protein consumption, and mid-arm circumference predicted one or both outcomes. CONCLUSIONS: Nutritional status is an important predictor of clinical outcomes in dementia and may provide an avenue for intervention.

Closer caregiver and care-recipient relationships predict lower informal costs of dementia care: The Cache County Dementia Progression Study.

INTRODUCTION: Identifying factors associated with lower dementia care costs is essential. We examined whether two caregiver factors were associated with lower costs of informal care. METHODS: A total of 271 care dyads of the Cache County Dementia Study were included. Estimates of informal costs were based on caregiver reports of time spent in care-related activities and inflation-adjusted 2012 Utah median hourly wages. Caregiver coping and emotional closeness with the care-recipient were assessed using the Ways of Coping Checklist-Revised and Relationship Closeness Scale, respectively. RESULTS: Higher closeness was associated with 24% lower costs (expß = 0.763 [95% confidence interval: 0.583-0.999]) in linear mixed models controlling for demographics and baseline dementia severity and duration. Problem-focused coping was not associated with informal costs (P = .354). DISCUSSION: Caregiver closeness, a potentially modifiable factor, predicted lower dementia informal care costs over time. Future studies examining the care environment in closer dyads may identify specific care-related behaviors or strategies that are associated with lower costs.

Dementia caregivers' coping strategies and their relationship to health and well-being: the Cache County Study.

OBJECTIVES: Prior research identifies that psychological outcomes among dementia caregivers are associated with their use of coping strategies. Few studies have tested the association of coping and health longitudinally. METHOD: This study examined factors associated with the use of coping strategies over time and their associations with physical and mental health outcomes in a population-based sample of 226 dementia caregivers in Cache County, Utah, USA. Caregivers annually completed the Ways of Coping Checklist-Revised, the Beck Anxiety Inventory, and a health interview. Care-recipient cognitive and functional abilities were obtained using the Mini-Mental State Exam and the Clinical Dementia Rating. Neuropsychiatric symptoms were assessed using the Neuropsychiatric Inventory. RESULTS: Caregivers most frequently identified providing care as a problem (37.6%). Linear mixed models of caregiver coping strategies found that the use of most strategies were stable except for increasing Avoidance among adult child caregivers (ß = 0.14, p = 0.048). On average, increased Wishful Thinking (ß = 2.48, p < 0.001) or Blames Self (ß = 1.06, p = 0.002) was associated with higher anxiety scores. Increased use of Blames Others among males (interaction, ß = 0.28, p = 0.02) and greater use of Wishful Thinking among younger caregivers (interaction, ß = -0.01, p = 0.01) were associated with more caregiver health conditions. Coping strategies were not associated with change in anxiety or health conditions over time. CONCLUSION: Our results emphasize the importance of caregiver coping strategies on caregiver health and well-being and may identify subgroups of persons at risk for worse outcomes.

Dementia severity and the longitudinal costs of informal care in the Cache County population.

BACKGROUND: Dementia costs are critical for influencing healthcare policy, but limited longitudinal information exists. We examined longitudinal informal care costs of dementia in a population-based sample. METHODS: Data from the Cache County Study included dementia onset, duration, and severity assessed by the Mini-Mental State Examination (MMSE), Clinical Dementia Rating Scale (CDR), and Neuropsychiatric Inventory (NPI). Informal costs of daily care (COC) was estimated based on median Utah wages. Mixed models estimated the relationship between severity and longitudinal COC in separate models for MMSE and CDR. RESULTS: Two hundred and eighty-seven subjects (53% female, mean (standard deviation) age was 82.3 (5.9) years) participated. Overall COC increased by 18% per year. COC was 6% lower per MMSE-point increase and compared with very mild dementia, COC increased over twofold for mild, fivefold for moderate, and sixfold for severe dementia on the CDR. CONCLUSIONS: Greater dementia severity predicted higher costs. Disease management strategies addressing dementia progression may curb costs.

Impact of offspring death on cognitive health in late life: the Cache County study.

OBJECTIVE: Experiencing the death of a child is associated with negative short-term mental health consequences, but less is known about cognitive outcomes and whether such associations extend to late life. We tested the hypothesis that experiencing an offspring death (OD) is associated with an increased rate of cognitive decline in late life. METHODS: This population-based longitudinal study observed four cognitive statuses spaced 3-4 years apart, linked to an extensive database containing objective genealogic and vital statistics data. Home visits were conducted with 3,174 residents of a rural county in northern Utah, initially without dementia, aged 65-105. Cognitive status was measured with the Modified Mini-Mental State Exam at baseline and at 3-, 7-, and 10-year follow-ups. OD was obtained from the Utah Population Database, which contains statewide birth and death records. RESULTS: In linear mixed models, controlling for age, gender, education, and apolipoprotein E status, subjects who experienced OD while younger than age 31 years experienced a significantly faster rate of cognitive decline in late life, but only if they had an ε4 allele. Reclassifying all OD (regardless of age) according to subsequent birth of another child, OD was only related to faster cognitive decline when there were no subsequent births. CONCLUSION: Experiencing OD in early adulthood has a long-term association with cognitive functioning in late life, with a gene-environment interaction at the apolipoprotein E locus. Subsequent birth of another child attenuates this association.

Vascular risk factors and neuropsychiatric symptoms in Alzheimer's disease: the Cache County Study.

OBJECTIVE: Knowledge of potentially modifiable risk factors for neuropsychiatric symptoms (NPS) in Alzheimer's disease (AD) is important. This study longitudinally explores modifiable vascular risk factors for NPS in AD. METHODS: Participants enrolled in the Cache County Study on Memory in Aging with no dementia at baseline were subsequently assessed over three additional waves, and those with incident (new onset) dementia were invited to join the Dementia Progression Study for longitudinal follow-up. A total of 327 participants with incident AD were identified and assessed for the following vascular factors: atrial fibrillation, hypertension, diabetes mellitus, angina, coronary artery bypass surgery, myocardial infarction, cerebrovascular accident, and use of antihypertensive or diabetes medicines. A vascular index (VI) was also calculated. NPS were assessed over time using the Neuropsychiatric Inventory (NPI). Affective and Psychotic symptom clusters were assessed separately. The association between vascular factors and change in NPI total score was analyzed using linear mixed model and in symptom clusters using a random effects model. RESULTS: No individual vascular risk factors or the VI significantly predicted change in any individual NPS. The use of antihypertensive medications more than four times per week was associated with higher total NPI and Affective cluster scores. CONCLUSIONS: Use of antihypertensive medication was associated with higher total NPI and Affective cluster scores. The results of this study do not otherwise support vascular risk factors as modifiers of longitudinal change in NPS in AD.

The association of traumatic brain injury with rate of progression of cognitive and functional impairment in a population-based cohort of Alzheimer's disease: the Cache County Dementia Progression Study.

BACKGROUND: There is limited research on factors that influence the rate of progression in Alzheimer's disease (AD). A history of traumatic brain injury (TBI) is associated with an increased risk for AD, but its role on the rate of dementia progression after the onset of AD has not been examined. METHODS: A population-based cohort of 325 persons with incident AD was followed for up to 11 years. The sample was 65% female with a mean (SD) age of dementia onset = 84.4 (6.4) years. History of TBI was categorized as number, severity (with or without loss of consciousness), and timing in relation to dementia onset (within ten years or more than ten years). Cognition was assessed by the Consortium to Establish a Registry of AD battery, and functional ability was assessed by the Clinical Dementia Rating Sum of Boxes. RESULTS: In linear mixed models, a history of TBI within ten years of onset showed faster progression of functional impairment (LR x2 = 10.27, p = 0.006), while those with TBI more than ten years before dementia onset had higher scores on a measure of list learning (ß = 1.61, p = 0.003) and semantic memory (ß = 0.75, p = 0.0035). CONCLUSIONS: History of TBI and its recency may be a useful factor to predict functional progression in the course of AD.

Variants in PPP3R1 and MAPT are associated with more rapid functional decline in Alzheimer's disease: the Cache County Dementia Progression Study.

BACKGROUND: Single-nucleotide polymorphisms (SNPs) located in the gene encoding the regulatory subunit of the protein phosphatase 2B (PPP3R1, rs1868402) and the microtubule-associated protein tau (MAPT, rs3785883) gene were recently associated with higher cerebrospinal fluid (CSF) tau levels in samples from the Knight Alzheimer's Disease Research Center at Washington University (WU) and Alzheimer's Disease Neuroimaging Initiative (ADNI). In these same samples, these SNPs were also associated with faster functional decline, or progression of Alzheimer's disease (AD) as measured by the Clinical Dementia Rating sum of boxes scores (CDR-sb). We attempted to validate the latter association in an independent, population-based sample of incident AD cases from the Cache County Dementia Progression Study (DPS). METHODS: All 92 AD cases from the DPS with a global CDR-sb ≤1 (mild) at initial clinical assessment who were later assessed on CDR-sb data on at least two other time points were genotyped at the two SNPs of interest (rs1868402 and rs3785883). We used linear mixed models to estimate associations between these SNPs and CDR-sb trajectory. All analyses were performed using Proc Mixed in SAS. RESULTS: Although we observed no association between rs3785883 or rs1868402 alone and change in CDR-sb (P > .10), there was a significant association between a combined genotype model and change in CDR-sb: carriers of the high-risk genotypes at both loci progressed >2.9 times faster than noncarriers (P = .015). When data from DPS were combined with previously published data from WU and ADNI, change in CDR-sb was 30% faster for each copy of the high-risk allele at rs3785883 (P = .0082) and carriers of both high-risk genotypes at both loci progressed 6 times faster (P < .0001) than all others combined. CONCLUSIONS: We replicate a previous report by Cruchaga et al that specific variations in rs3785883 and rs1868402 are associated with accelerated progression of AD. Further characterization of this association will provide a better understanding of how genetic factors influence the rate of progression of AD and could provide novel insights into preventative and therapeutic strategies.

Caregiver coping strategies predict cognitive and functional decline in dementia: the Cache County Dementia Progression Study.

OBJECTIVES: Few longitudinal studies have studied the influence of the care environment on the clinical progression of dementia. We examined whether caregiver coping strategies predict dementia progression in a population-based sample. DESIGN: Longitudinal, prospective cohort study. SETTING: Cache County (Utah) population. PARTICIPANTS: A total of 226 persons with dementia, and their caregivers, were assessed semiannually for up to 6 years. MEASUREMENTS: Ways of Coping Checklist-Revised, Mini-Mental State Examination (MMSE), and Clinical Dementia Rating (CDR). RESULTS: Mean (SD) age of dementia onset in persons with dementia was 82.11 (5.84) years and mean caregiver age was 67.41 (13.95) years. Mean (SD) follow-up was 1.65 (1.63) years from baseline. In univariate linear mixed-effects models, increasing use of problem-focused and counting blessings by caregivers was associated with slower patient worsening on the MMSE. Problem-focused coping, seeking social support, and wishful thinking were associated with slower Clinical Dementia Rating Scale sum of boxes (CDR-sb) worsening. Considering covariates, increasing use of problem-focused coping was associated with 0.70 points per year less worsening on the MMSE and 0.55 points per year less worsening on the CDR-sb. Compared with no use, the "regular" use of this strategy was associated with 2 points per year slower worsening on the MMSE and 1.65 points per year slower worsening on the CDR-sb. CONCLUSIONS: Caregiver coping strategies are associated with slower dementia progression. Developing interventions that target these strategies may benefit dementia patients.

Stressful life events and cognitive decline in late life: moderation by education and age. The Cache County Study.

OBJECTIVE: Stressful life events (SLE) have been associated with increased dementia risk, but their association with cognitive decline has been inconsistent. In a longitudinal population-based study of older individuals, we examined the association between SLE and cognitive decline, and the role of potential effect modifiers. METHODS: A total of 2665 non-demented participants of the Cache County Memory Study completed an SLE questionnaire at Wave 2 and were revisited 4 and 7 years later. The events were represented via several scores: total number, subjective rating (negative, positive, and unexpected), and a weighted summary based on their impact. Cognition was assessed at each visit with the modified Mini-Mental State Exam. General linear models were used to examine the association between SLE scores and cognition. Effect modification by age, education, and APOE genotype was tested. RESULTS: Years of formal education (p = 0.006) modified the effect of number of SLE, and age (p = 0.009) modified the effect of negative SLE on the rate of cognitive decline. Faster decline was observed among those with fewer years of education experiencing more SLE and also among younger participants experiencing more negative SLE. There was no association between other indicators of SLE and cognitive decline. APOE genotype did not modify any of the aforementioned associations. CONCLUSIONS: The effects of SLE on cognition in late life are complex and vary by individual factors such as age and education. These results may explain some of the contradictory findings in the literature.

Effects of general medical health on Alzheimer's progression: the Cache County Dementia Progression Study.

BACKGROUND: Several observational studies have suggested a link between health status and rate of decline among individuals with Alzheimer's disease (AD). We sought to quantify the relationship in a population-based study of incident AD, and to compare global comorbidity ratings to counts of comorbid conditions and medications as predictors of AD progression. METHODS: This was a case-only cohort study arising from a population-based longitudinal study of memory and aging, in Cache County, Utah. Participants comprised 335 individuals with incident AD followed for up to 11 years. Patient descriptors included sex, age, education, dementia duration at baseline, and APOE genotype. Measures of health status made at each visit included the General Medical Health Rating (GMHR), number of comorbid medical conditions, and number of non-psychiatric medications. Dementia outcomes included the Mini-Mental State Examination (MMSE), Clinical Dementia Rating - sum of boxes (CDR-sb), and the Neuropsychiatric Inventory (NPI). RESULTS: Health status tended to fluctuate over time within individuals. None of the baseline medical variables (GMHR, comorbidities, and non-psychiatric medications) was associated with differences in rates of decline in longitudinal linear mixed effects models. Over time, low GMHR ratings, but not comorbidities or medications, were associated with poorer outcomes (MMSE: ß = -1.07 p = 0.01; CDR-sb: ß = 1.79 p < 0.001; NPI: ß = 4.57 p = 0.01). CONCLUSIONS: Given that time-varying GMHR, but not baseline GMHR, was associated with the outcomes, it seems likely that there is a dynamic relationship between medical and cognitive health. GMHR is a more sensitive measure of health than simple counts of comorbidities or medications. Since health status is a potentially modifiable risk factor, further study is warranted.

Caregivers' relationship closeness with the person with dementia predicts both positive and negative outcomes for caregivers' physical health and psychological well-being.

Closer relationships between caregivers and care recipients with dementia are associated with positive outcomes for care recipients, but it is unclear if closeness is a risk or protective factor for the health and psychological wellbeing of caregivers. We examined 234 care dyads from the population-based Cache County Dementia Progression Study. Caregivers included spouses (49%) and adult offspring (51%). Care recipients mostly had dementia of the Alzheimer's type (62%). Linear mixed models tested associations between relationship closeness at baseline or changes in closeness prior to versus after dementia onset, with baseline levels and changes over time in caregiver affect (Affect Balance Scale, ABS), depression (Beck Depression Inventory, BDI), and mental and physical health (components of the Short-Form Health Survey, SF-12). After controlling for demographic characteristics of the caregiver, number of caregiver health conditions, and characteristics of the care recipient (type of dementia, functional ability, and behavioral disturbances), we found that higher baseline closeness predicted higher baseline SF-12 mental health scores (better mental health) and lower depression. Higher baseline closeness also predicted greater worsening over time in ABS and SF-12 mental health. In addition, caregivers who reported a loss of closeness in their relationship with the care recipient from pre- to post-dementia displayed improved scores on ABS and SF-12 mental health, but worse SF-12 physical health over the course of the study. These results suggest that closeness and loss of closeness in the care dyad may be associated with both positive and adverse outcomes for caregivers, both cross-sectionally and over time.

Effects of Food and Drug Administration-approved medications for Alzheimer's disease on clinical progression.

BACKGROUND: Observational studies suggest that cholinesterase inhibitors and/or memantine may delay clinical progression of Alzheimer's disease (AD) in 40% of individuals taking the medications. Given this response and existence of side effects, we sought to quantify medication use and benefits in a population-based study of incident AD cases. METHODS: The Cache County Dementia Progression Study enrolled and followed a cohort of 327 incident AD cases for a maximum of 9 years. Drug exposure was expressed using a persistency index (PI), calculated as total years of drug use divided by total years of observation. Linear mixed-effects models examined PI, and interactions with sex and apolipoprotein E (APOE) as predictors of clinical progression on the Mini-Mental State Examination and Clinical Dementia Rating-Sum of Boxes. RESULTS: A total of 69 participants (21.1%) reported having ever used cholinesterase inhibitors or memantine. There was a strong three-way interaction between PI, sex, and time. Among women, a higher PI (i.e., greater duration of use) of cholinesterase inhibitors was associated with slower progression on the Mini-Mental State Examination and Clinical Dementia Rating-Sum of Boxes, particularly among those with an APOE ɛ4 allele. In contrast, higher PI was associated with faster progression in males. CONCLUSION: A low percentage of individuals with AD in the community are taking cholinesterase inhibitors or memantine. This study suggests that women, particularly those with an APOE ɛ4 allele, may benefit the most from these medications. With the newly approved increased dose of donepezil, it will be imperative to determine whether a higher dose is needed in men or whether other factors warrant consideration.

Early parental death and remarriage of widowed parents as risk factors for Alzheimer disease: the Cache County study.

OBJECTIVES: Early parental death is associated with lifelong tendencies toward depression and chronic stress. We tested the hypothesis that early parental death is associated with higher risk for Alzheimer disease (AD) in offspring. DESIGN: A population-based epidemiological study of dementia with detailed clinical evaluations, linked to one of the world's richest sources of objective genealogical and vital statistics data. SETTING: Home visits with residents of a rural county in northern Utah. PARTICIPANTS: 4,108 subjects, aged 65-105. MEASUREMENTS: Multistage dementia ascertainment protocol implemented in four triennial waves, yielding expert consensus diagnoses of 570 participants with AD and 3,538 without dementia. Parental death dates, socioeconomic status, and parental remarriage after widowhood were obtained from the Utah Population Database, a large genealogical database linked to statewide birth and death records. RESULTS: Mother's death during subject's adolescence was significantly associated with higher rate of AD in regression models that included age, gender, education, APOE genotype, and socioeconomic status. Father's death before subject age 5 showed a weaker association. In stratified analyses, associations were significant only when the widowed parent did not remarry. Parental death associations were not moderated by gender or APOE genotype. Findings were specific to AD and not found for non-AD dementia. CONCLUSIONS: Parental death during childhood is associated with higher prevalence of AD, with different critical periods for father's versus mother's death, with strength of these associations attenuated by remarriage of the widowed parent.

Progression of cognitive, functional, and neuropsychiatric symptom domains in a population cohort with Alzheimer dementia: the Cache County Dementia Progression study.

OBJECTIVES: Progression of Alzheimer dementia (AD) is highly variable. Most estimates derive from convenience samples from dementia clinics or research centers where there is substantial potential for survival bias and other distortions. In a population-based sample of incident AD cases, we examined progression of impairment in cognition, function, and neuropsychiatric symptoms, and the influence of selected variables on these domains. DESIGN: Longitudinal, prospective cohort study. SETTING: Cache County (Utah). PARTICIPANTS: Three hundred twenty-eight persons with a diagnosis of possible/probable AD. MEASUREMENTS: Mini-Mental State Exam (MMSE), Clinical Dementia Rating sum-of-boxes (CDR-sb), and Neuropsychiatric Inventory (NPI). RESULTS: Over a mean follow-up of 3.80 (range: 0.07-12.90) years, the mean (SD) annual rates of change were -1.53 (2.69) scale points on the MMSE, 1.44 (1.82) on the CDR-sb, and 2.55 (5.37) on the NPI. Among surviving participants, 30% to 58% progressed less than 1 point per year on these measures, even 5 to 7 years after dementia onset. Rates of change were correlated between MMSE and CDR-sb (r = -0.62, df = 201, p < 0.001) and between the CDR-sb and NPI (r = 0.20, df = 206, p < 0.004). Female subjects (LR χ = 8.7, df = 2, p = 0.013) and those with younger onset (likelihood ratio [LR] χ = 5.7, df = 2, p = 0.058) declined faster on the MMSE. Although one or more apolipoprotein E ε 4 alleles and ever use of FDA-approved antidementia medications were associated with initial MMSE scores, neither was related to the rate of progression in any domain. CONCLUSIONS: A significant proportion of persons with AD progresses slowly. The results underscore differences between population-based versus clinic-based samples and suggest ongoing need to identify factors that may slow the progression of AD.

Diet quality is associated with better cognitive test performance among aging men and women.

Most studies of association between diet and cognition among the elderly focus on the role of single nutrients or foods and ignore the complexity of dietary patterns and total diet quality. We prospectively examined associations between an index of diet quality and cognitive function and decline among elderly men and women of the Cache County Study on Memory and Aging in Utah. In 1995, 3634 resident men and women > or =65 y of age completed a baseline survey that included a 142-item FFQ. Cognition was assessed using an adapted version of the Modified Mini-Mental State Examination (3MS) at baseline and 3 subsequent interviews spanning approximately 11 y. A recommended food score (RFS) and non-RFS were computed by summing the number of recommended foods (n = 57) and nonrecommended foods (n = 23) regularly consumed. Multivariable-mixed models were used to estimate associations between the RFS and non-RFS and average 3MS score over time. Those in the highest quartile of RFS scored 1.80 points higher on the baseline 3MS test than did those in the lowest quartile of RFS (P < 0.001). This effect was strengthened over 11 y of follow-up. Those with the highest RFS declined by 3.41 points over 11 y compared with the 5.2-point decline experienced by those with the lowest RFS (P = 0.0013). The non-RFS was not associated with cognitive scores. Consuming a diverse diet that includes a variety of recommended foods may help to attenuate age-related cognitive decline among the elderly.

Relative risk for Alzheimer disease based on complete family history.

OBJECTIVE: The inherited component for Alzheimer disease (AD) risk has focused on close relatives; consideration of the full family history may improve accuracy and utility of risk estimates. METHODS: A population resource including a genealogy of Utah pioneers from the 1800s linked to Utah death certificates was used to estimate relative risk for AD based on specific family history constellations, including from first- to third-degree relatives. RESULTS: Any affected first-degree relatives (FDR) significantly increased risk of AD (≥1 FDRs: relative risk [RR] 1.73, 95% confidence interval [CI] [1.59-1.87]; ≥2 FDRs: RR 3.98 [3.26-4.82]; ≥3 FDRs: RR 2.48 [1.07-4.89]; ≥4 FDRs: RR 14.77 [5.42-32.15]). Affected second-degree relatives (SDR) increased risk even in the presence of affected FDRs (FDR = 1 with SDR = 2: RR 21.29 [5.80-54.52]). AD only in third-degree relatives (TDR) also increased risk (FDR = 0, SDR = 0, TDR ≥3: RR 1.43 [1.21-1.68]). Mixed evidence was observed for differences in risk based on maternal compared to paternal inheritance; higher risks for men than women with equivalent family history, and higher risk for individuals with at least one affected FDR regardless of the relative's age at death, were observed. CONCLUSIONS: This population-based estimation of RRs for AD based on family history ascertained from extended genealogy data indicates that inherited genetic factors have a broad influence, extending beyond immediate relatives. Providers should consider the full constellation of family history when counseling patients and families about their risk of AD.