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PILRA (rs1859788 A > G) has been suggested to be a protective variant for Alzheimer's disease (AD) and is an entry co-receptor for herpes simplex virus-1. We conducted a nested case-control study of 360 1:1-matched AD subjects. Interactions between the PILRA-A allele, APOE risk variants (epsilon 3/epsilon 4 or epsilon 4/epsilon 4) and GM17 for AD risk were modelled. The associations were cross-validated using two independent whole-genome sequencing datasets. We found negative interactions between PILRA-A and GM17 (OR 0.72, 95% CI 0.52-1.00) and between PILRA-A and APOE risk variants (OR 0.56, 95% CI 0.32-0.98) in the discovery dataset. In the replication cohort, a joint effect of PILRA and PILRA x GM 17/17 was observed for the risk of developing AD (p .02). Here, we report a negative effect modification by PILRA on APOE and GM17 high-risk variants for future AD risk in two independent datasets. This highlights the complex genetics of AD.

Background: Amyloid-β (Aβ), the key constituent of Alzheimer’s disease (AD) plaques, has antimicrobial properties. Objective: To investigate the association between plasma Aβ and antibodies against the AD-related pathogens herpes simplex virus (HSV), cytomegalovirus (CMV), and C. pneumoniae. Methods: Plasma from 339 AD cases, obtained on average 9.4 years (±4.00) before diagnosis, and their matched controls were analyzed for Aβ40 and Aβ42 concentrations with Luminex xMAP technology and INNOBIA plasma Aβ-form assays. Enzyme-linked immunosorbent assays were utilized for analyses of anti-HSV immunoglobulin (Ig) G, anti-HSV1 IgG, anti-HSV2 IgG, anti-CMV IgG, and anti-C. pneumoniae IgG. Follow-up samples were available for 150 of the cases. Results: Presence and levels of anti-HSV1 IgG, anti-HSV2 IgG, anti-CMV IgG, and anti-C. pneumoniae IgG did not correlate with concentrations of Aβ42 or Aβ40 in cases or controls. Conclusion: Levels of plasma Aβ were not associated with antibodies against different AD-related pathogens.

Background: Amyloid-beta (A beta), the key constituent of Alzheimer's disease (AD) plaques, has antimicrobial properties. Objective: To investigate the association between plasma A beta and antibodies against the AD-related pathogens herpes simplex virus (HSV), cytomegalovirus (CMV), and C. pneumoniae. Methods: Plasma from 339 AD cases, obtained on average 9.4 years (+/- 4.00) before diagnosis, and their matched controls were analyzed for A beta(40) and A beta(42) oncentrations with Luminex xMAP technology and INNOBIA plasma A beta-form assays. Enzyme-linked immunosorbent assays were utilized for analyses of anti-HSV immunoglobulin (Ig) G, anti-HSV1 IgG, anti-HSV2 IgG, anti-CMV IgG, and anti-C. pneumoniae IgG. Follow-up samples were available for 150 of the cases. Results: Presence and levels of anti-HSV1 IgG, anti-HSV2 IgG, anti-CMV IgG, and anti-C. pneumoniae IgG did not correlate with concentrations of A beta 42 or A beta 40 in cases or controls. Conclusion: Levels of plasma A beta were not associated with antibodies against different AD-related pathogens.

How acute hyperglycaemia affects memory functions and functional brain responses in individuals with and without type 2 diabetes is unclear. Our aim was to study the association between acute hyperglycaemia and working, semantic, and episodic memory in participants with type 2 diabetes compared to a sex- A nd age-matched control group. We also assessed the effect of hyperglycaemia on working memory-related brain activity. A total of 36 participants with type 2 diabetes and 34 controls (mean age, 66 years) underwent hyperglycaemic clamp or placebo clamp in a blinded and randomised order. Working, episodic, and semantic memory were tested. Overall, the control group had higher working memory (mean z-score 33.15 ± 0.45) than the group with type 2 diabetes (mean z-score 31.8 ± 0.44, p = 0.042) considering both the placebo and hyperglycaemic clamps. Acute hyperglycaemia did not influence episodic, semantic, or working memory performance in either group. Twenty-two of the participants (10 cases, 12 controls, mean age 69 years) were randomly invited to undergo the same clamp procedures to challenge working memory, using 1-, 2-, and 3-back, while monitoring brain activity by blood oxygen level-dependent functional magnetic resonance imaging (fMRI). The participants with type 2 diabetes had reduced working memory during the 1- A nd 2-back tests. fMRI during placebo clamp revealed increased BOLD signal in the left lateral frontal cortex and the anterior cingulate cortex as a function of working memory load in both groups (3>2>1). During hyperglycaemia, controls showed a similar load-dependent fMRI response, whereas the type 2 diabetes group showed decreased BOLD response from 2-to 3-back. These results suggest that impaired glucose metabolism in the brain affects working memory, possibly by reducing activity in important frontal brain areas in persons with type 2 diabetes.

Increasing evidence implicates HSV type 1 (HSV1) in the pathogenesis of late-onset Alzheimer disease (AD). HSV1 has evolved highly sophisticated strategies to evade host immunosurveillance. One strategy involves encoding a decoy Fc gamma receptor (Fc gamma R), which blocks Fc-mediated effector functions, such as Ab-dependent cellular cytotoxicity. Ig gamma marker (GM) allotypes, encoded by highly polymorphic IGHG genes on chromosome 14q32, modulate this immunoevasion strategy, and thus may act as effect modifiers of the HSV1-AD association. In this nested case-control human study, 365 closely matched case-control pairs-whose blood was drawn on average 9.6 y before AD diagnosis-were typed for GM alleles by a TagMan genotyping assay. APOE genotype and a genetic risk score based on nine additional previously known AD risk genes (ABCA7, BIN1, CD33, CLU, CR1, EPHA1, MS4A4E, NECTIN2, and PICALM) were extracted from a genome-wide association study analysis. Antiviral Abs were measured by ELISA. Conditional logistic regression models were applied. The distribution of GM 3/17 genotypes differed significantly between AD cases and controls, with higher frequency of GM 17/17 homozygotes in AD cases as compared with controls (19.8 versus 10.7%, p = 0.001). The GM 17/17 genotype was associated with a 4-fold increased risk of AD (odds ratio 4.142,p < 0.001). In conclusion, the results of this study demonstrate that Ig GM 17/17 genotype contributes to the risk of later AD development, independent of apolipoprotein epsilon 4 genotype and other AD risk genes, and explain, at least in part, why every HSV1-infected person is not equally likely to develop HSV1-associated AD.

The number of older people living with cancer and cardiometabolic conditions is increasing, but little is known about how specific combinations of these conditions impact mortality. A total of 22,692 participants aged 65 years and older from four international cohorts were followed-up for mortality for an average of 10 years (8,596 deaths). Data were harmonized across cohorts and mutually exclusive groups of disease combinations were created for cancer, myocardial infarction (MI), stroke, and diabetes at baseline. Cox proportional hazards models for all-cause mortality were used to estimate the age- and sex-adjusted hazard ratio and rate advancement period (RAP) (in years). At baseline, 23.6% (n = 5,116) of participants reported having one condition and 4.2% (n = 955) had two or more conditions. Data from all studies combined showed that the RAP increased with each additional condition. Diabetes advanced the rate of dying by the most years (5.26 years; 95% confidence interval [CI], 4.536.00), but the effect of any single condition was smaller than the effect of disease combinations. Some combinations had a significantly greater impact on the period by which the rate of death was advanced than others with the same number of conditions, for example, 10.9 years (95% CI, 9.412.6) for MI and diabetes versus 6.4 years (95% CI, 4.38.5) for cancer and diabetes. Combinations of cancer and cardiometabolic conditions accelerate mortality rates in older adults differently. Although most studies investigating mortality associated with multimorbidity used disease counts, these provide little guidance for managing complex patients as they age.

IntroductionHerpes simplex virus type 1 (HSV1) in combination with genetic susceptibility has previously been implicated in Alzheimer's disease (AD) pathogenesis. MethodsPlasma from 360 AD cases, obtained on average 9.6years before diagnosis, and their age- and sex-matched controls, were analyzed for anti-HSV1 immunoglobulin (Ig) G with enzyme-linked immunosorbent assays (ELISAs). APOE genotype and nine other selected risk genes for AD were extracted from a genome-wide association study analysis by deCODE genetics, Reykjavik, Iceland. ResultsThe interaction between APOE epsilon 4 heterozygosity (APOE epsilon 2/epsilon 4 or epsilon 3/epsilon 4) and anti-HSV1 IgG carriage increased the risk of AD (OR 4.55, P=.02). A genetic risk score based on the nine AD risk genes also interacted with anti-HSV1 IgG for the risk of developing AD (OR 2.35, P=.01). DiscussionThe present findings suggest that the APOE epsilon 4 allele and other AD genetic risk factors might potentiate the risk of HSV1-associated AD.

Background: Several environmental factors, including infectious agents, have been suggested to cause Alzheimer's disease (AD). Cytomegalovirus (CMV) has been associated with AD in several recent studies. Objective: To investigate whether carriage of CMV, alone or in combination with Herpes simplex virus (HSV), increased the risk of developing AD. Methods: Plasma samples from 360 AD cases (75.3% women, mean age 61.2 years), taken an average of 9.6 years before AD diagnosis, and 360 age-, sex-, cohort-, and sampling date matched dementia-free controls were analyzed to detect antiCMV (immunoglobulin [Ig] G and IgM), group-specific anti-HSV (IgG and IgM), and specific anti-HSV1 and HSV2 IgG antibodies by enzyme-linked immunosorbent assays. AD cases and dementia-free controls were compared using conditional logistic regression analyses. Results: The presence of anti-CMV IgG antibodies did not increase the risk ofAD(odds ratio [OR], 0.857; p = 0.497). Among AD cases, an association between CMV and HSV1 carriage was detected (OR 7.145, p < 0.001); in a conditional logistic regression model, the interaction between CMV and HSV1 was associated with AD development (OR 5.662; p = 0.007). Conclusion: The present findings do not support a direct relationship between CMV infection and the development of AD; however, an interaction between CMV and HSV1 was found to be associated significantly with AD development. These findings suggest that CMV infection facilitates the development of HSV1-associated AD, possibly via its effects on the immune system.

The association between adherence to Mediterranean diet (MD) and hip fracture incidence is not yet established. In a diverse population of elderly, increased adherence to MD was associated with lower hip fracture incidence. Except preventing major chronic diseases, adhering to MD might have additional benefits in lowering hip fracture risk. INTRODUCTION: Hip fractures constitute a major public health problem among older adults. Latest evidence links adherence to Mediterranean diet (MD) with reduced hip fracture risk, but still more research is needed to elucidate this relationship. The potential association of adherence to MD with hip fracture incidence was explored among older adults. METHODS: A total of 140,775 adults (116,176 women, 24,599 men) 60 years and older, from five cohorts from Europe and the USA, were followed-up for 1,896,219 person-years experiencing 5454 hip fractures. Diet was assessed at baseline by validated, cohort-specific, food-frequency questionnaires, and hip fractures were ascertained through patient registers or telephone interviews/questionnaires. Adherence to MD was evaluated by a scoring system on a 10-point scale modified to be applied also to non-Mediterranean populations. In order to evaluate the association between MD and hip fracture incidence, cohort-specific hazard ratios (HR), adjusted for potential confounders, were estimated using Cox proportional-hazards regression and pooled estimates were subsequently derived implementing random-effects meta-analysis. RESULTS: A two-point increase in the score was associated with a significant 4% decrease in hip fracture risk (pooled adjusted HR 0.96; 95% confidence interval (95% CI) 0.92-0.99, pheterogeneity = 0.446). In categorical analyses, hip fracture risk was lower among men and women with moderate (HR 0.93; 95% CI 0.87-0.99) and high (HR 0.94; 95% CI 0.87-1.01) adherence to the score compared with those with low adherence. CONCLUSIONS: In this large sample of older adults from Europe

BACKGROUND: Hip fractures are associated with diminished quality of life and survival especially amongst the elderly. OBJECTIVE: All-cause mortality after hip fracture was investigated to assess its magnitude. METHODS: A total of 122 808 participants from eight cohorts in Europe and the USA were followed up for a mean of 12.6 years, accumulating 4273 incident hip fractures and 27 999 deaths. Incident hip fractures were assessed through telephone interviews/questionnaires or national inpatient/fracture registries, and causes of death were verified with death certificates. Cox proportional hazards models and the time-dependent variable methodology were used to assess the association between hip fracture and mortality and its magnitude at different time intervals after the injury in each cohort. We obtained the effect estimates through a random-effects meta-analysis. RESULTS: Hip fracture was positively associated with increased all-cause mortality; the hazard ratio (HR) in the fully adjusted model was 2.12, 95% confidence interval (CI) 1.76-2.57, after adjusting for potential confounders. This association was stronger amongst men [HR: 2.39, 95% CI: 1.72-3.31] than amongst women [HR: 1.92, 95% CI: 1.54-2.39], although this difference was not significant. Mortality was higher during the first year after the hip fracture [HR: 2.78, 95% CI: 2.12-3.64], but it remained elevated without major fluctuations after longer time since hip fracture [HR (95% CI): 1.89 (1.50-2.37) after 1-4 years; 2.15 (1.81-2.55) after 4-8 years; 1.79 (1.57-2.05) after 8 or more years]. CONCLUSION: In this large population-based sample of older persons across eight cohorts, hip fracture was associated with excess short- and long-term all-cause mortality in both sexes.

Objectives: To evaluate, among the elderly, the association of self-rated health (SRH) with mortality, and to identify determinants of self-rating health as “at-least-good”. Study design: Individual data on SRH and important covariates were obtained for 424,791 European and United States residents, ≥60 years at recruitment (1982–2008), in eight prospective studies in the Consortium on Health and Ageing: Network of Cohorts in Europe and the United States (CHANCES). In each study, adjusted mortality ratios (hazard ratios, HRs) in relation to SRH were calculated and subsequently combined with random-effect meta-analyses. Main outcome measures: All-cause, cardiovascular and cancer mortality. Results: Within the median 12.5 years of follow-up, 93,014 (22%) deaths occurred. SRH “fair” or “poor” vs. “at-least-good” was associated with increased mortality: HRs 1.46 (95% CI 1·23–1.74) and 2.31 (1.79–2.99), respectively. These associations were evident: for cardiovascular and, to a lesser extent, cancer mortality, and within-study, within-subgroup analyses. Accounting for lifestyle, sociodemographic, somatometric factors and, subsequently, for medical history explained only a modest amount of the unadjusted associations. Factors favourably associated with SRH were: sex (males), age (younger-old), education (high), marital status (married/cohabiting), physical activity (active), body mass index (non-obese), alcohol consumption (low to moderate) and previous morbidity (absence). Conclusion: SRH provides a quick and simple tool for assessing health and identifying groups of elders at risk of early mortality that may be useful also in clinical settings. Modifying determinants of favourably rating health, e.g. by increasing physical activity and/or by eliminating obesity, may be important for older adults to “feel healthy” and “be healthy”.

Objectives To evaluate, among the elderly, the association of self-rated health (SRH) with mortality, and to identify determinants of self-rating health as “at-least-good”. Study design Individual data on SRH and important covariates were obtained for 424,791 European and United States residents, ≥60 years at recruitment (1982–2008), in eight prospective studies in the Consortium on Health and Ageing: Network of Cohorts in Europe and the United States (CHANCES). In each study, adjusted mortality ratios (hazard ratios, HRs) in relation to SRH were calculated and subsequently combined with random-effect meta-analyses. Main outcome measures All-cause, cardiovascular and cancer mortality. Results Within the median 12.5 years of follow-up, 93,014 (22%) deaths occurred. SRH “fair” or “poor” vs. “at-least-good” was associated with increased mortality: HRs 1.46 (95% CI 1·23–1.74) and 2.31 (1.79–2.99), respectively. These associations were evident: for cardiovascular and, to a lesser extent, cancer mortality, and within-study, within-subgroup analyses. Accounting for lifestyle, sociodemographic, somatometric factors and, subsequently, for medical history explained only a modest amount of the unadjusted associations. Factors favourably associated with SRH were: sex (males), age (younger-old), education (high), marital status (married/cohabiting), physical activity (active), body mass index (non-obese), alcohol consumption (low to moderate) and previous morbidity (absence). Conclusion SRH provides a quick and simple tool for assessing health and identifying groups of elders at risk of early mortality that may be useful also in clinical settings. Modifying determinants of favourably rating health, e.g. by increasing physical activity and/or by eliminating obesity, may be important for older adults to “feel healthy” and “be healthy”.