Bleeding risk with rivaroxaban compared with vitamin K antagonists in patients aged 80 years or older with atrial fibrillation.

OBJECTIVE: Direct oral anticoagulants have been evaluated in the general population, but proper evidence for their safe use in the geriatric population is still missing. We compared the bleeding risk of a direct oral anticoagulant (rivaroxaban) and vitamin K antagonists (VKAs) among French geriatric patients with non-valvular atrial fibrillation (AF) aged ≥80 years. METHODS: We performed a sequential observational prospective cohort study, using data from 33 geriatric centres. The sample comprised 908 patients newly initiated on VKAs between September 2011 and September 2014 and 995 patients newly initiated on rivaroxaban between September 2014 and September 2017. Patients were followed up for up to 12 months. One-year risks of major, intracerebral, gastrointestinal bleedings, ischaemic stroke and all-cause mortality were compared between rivaroxaban-treated and VKA-treated patients with propensity score matching and Cox models. RESULTS: Major bleeding risk was significantly lower in rivaroxaban-treated patients (7.4/100 patient-years) compared with VKA-treated patients (14.6/100 patient-years) after multivariate adjustment (HR 0.66; 95% CI 0.43 to 0.99) and in the propensity score-matched sample (HR 0.53; 95% CI 0.33 to 0.85). Intracerebral bleeding occurred less frequently in rivaroxaban-treated patients (1.3/100 patient-years) than in VKA-treated patients (4.0/100 patient-years), adjusted HR 0.59 (95% CI 0.24 to 1.44) and in the propensity score-matched sample HR 0.26 (95% CI 0.09 to 0.80). Major lower bleeding risk was largely driven by lower risk of intracerebral bleeding. CONCLUSIONS: Our study findings indicate that bleeding risk, largely driven by lower risk of intracerebral bleeding, is lower with rivaroxaban than with VKA in stroke prevention in patients ≥80 years old with non-valvular AF.

Allometric scaling of brain regions to intra-cranial volume: An epidemiological MRI study.

There is growing evidence that sub-structures of the brain scale allometrically to total brain size, that is, in a non-proportional and non-linear way. Here, scaling of different volumes of interest (VOI) to intra-cranial volume (ICV) was examined. It was assessed whether scaling was allometric or isometric and whether scaling coefficients significantly differed from each other. We also tested to what extent allometric scaling of VOI was introduced by the automated segmentation technique. Furthermore, reproducibility of allometric scaling was studied different age groups and study populations. Study samples included samples of cognitively healthy adults from the community-based Age Gene/Environment Susceptibility-Reykjavik Study (AGES-Reykjavik Study) (N = 3,883), the Coronary Artery Risk Development in Young Adults Study (CARDIA) (N =709), and the Alzheimer's Disease Neuroimaging Initiative (ADNI) (N = 180). Data encompassed participants with different age, ethnicity, risk factor profile, and ICV and VOI obtained with different automated MRI segmentation techniques. Our analysis showed that (1) allometric scaling is a trait of all parts of the brain, (2) scaling of neo-cortical white matter, neo-cortical gray matter, and deep gray matter structures including the cerebellum are significantly different from each other, and (3) allometric scaling of brain structures cannot solely be explained by age-associated atrophy, sex, ethnicity, or a systematic bias from study-specific segmentation algorithm, but appears to be a true feature of brain geometry. Hum Brain Mapp 38:151-164, 2017. © 2016 Wiley Periodicals, Inc.

Arterial stiffness and medial temporal lobe atrophy in elders with memory disorders.

OBJECTIVES: Hypertension is a risk factor for cognitive impairment and dementia. Arterial stiffness could be involved in the mechanisms of vascular cognitive impairment and in Alzheimer's disease. We examined the association between arterial stiffness, assessed by carotid-femoral pulse wave velocity (PWV), and medial temporal lobe (MTL) atrophy, a biomarker of Alzheimer's disease. METHODS: Elderly community-dwelling study participants (n = 149) with memory complaints were diagnosed with Alzheimer's disease (n = 62) or mild cognitive impairment (n = 87) at a memory clinic. PWV, peripheral and central blood pressure (SBP), and pulse pressure (PP) were measured. MTL was graded on MRI according to the Scheltens' scale. RESULTS: Mean age was 79.5 (SD = 5) years old, 36% of study participants were men. MTL was absent or discrete in 23.5%, moderate in 53.0% and severe in 23.5% of study participants. PWV was 9.3 (2.2) m/s in none or discrete, 11.1 (2.8) in moderate and 13.5 (4.0) in severe MTL atrophy (P < 0.0001). PWV, central SBP, and central PP were overall associated with MTL atrophy after adjustment for age, sex, antihypertensive treatments and white matter lesions, and further adjusted for mean BP for PWV, whereas peripheral SBP and PP were not associated with MTL atrophy. PWV was significantly associated with severe MTL atrophy [odds ratio = 3.69 (95% confidence interval = 1.69-8.05), P = 0.001] and marginally associated with moderate MTL atrophy [1.80 (0.92-3.53), P = 0.09]. Furthermore PWV was significantly associated with severe MTL atrophy in Alzheimer's disease and mild cognitive impairment study participants separately. CONCLUSION: The result of this study suggests a role of arterial stiffness in the pathogenesis of Alzheimer's disease.

Different susceptibility of medial temporal lobe and basal ganglia atrophy rates to vascular risk factors.

Atrophy of the medial temporal lobe (MTL) and basal ganglia (BG) are characteristic of various neurodegenerative diseases in older people. In search of potentially modifiable factors that lead to atrophy in these structures, we studied the association of vascular risk factors with atrophy of the MTL and BG in 368 nondemented men and women (born, 1907-1935) who participated in the Age, Gene/Environment, Susceptibility-Reykjavik Study. A fully automated segmentation pipeline estimated volumes of the MTL and BG from whole-brain magnetic resonance imaging performed at baseline and 2.4 years later. Linear regression models showed higher systolic and diastolic blood pressures and the presence of Apo E ε4 were independently associated with increased atrophy of the MTL but no association of vascular risk factors with atrophy of the BG. The different susceptibility of MTL and BG atrophy to the vascular risk factors suggests perfusion of the BG is relatively preserved when vascular risk factors are present.

Does cognitive function increase over time in the healthy elderly?

BACKGROUND: In dementia screening, most studies have focused on early cognitive impairment by comparing patients suffering from mild dementia or mild cognitive impairment with normal subjects. Few studies have focused on modifications over time of the cognitive function in the healthy elderly. The objective of the present study was to analyze the cognitive function changes of two different samples, born > 15 years apart. METHOD: A first sample of 204 cognitively normal participants was recruited in the memory clinic of Broca hospital between 1991 and 1997. A second sample of 177 cognitively normal participants was recruited in 2008-2009 in the same institution. Both samples were from the same districts of Paris and were assessed with the same neuropsychological test battery. Mean cognitive test scores were compared between 1991 and 2008 samples, between < 80 years old and ≥ 80 years old in 1991 and 2008 samples, and finally between subjects < 80 year old of 1991 sample and subjects ≥ 80 years old of the 2008 sample. Means were compared with T-tests stratified on gender, age-groups and educational level. RESULTS: Cognitive scores were significantly higher in the 2008 sample. Participants < 80 years old outperformed those ≥ 80 in both samples. However, participants < 80 years old in 1991 sample and subjects ≥ 80 in the 2008 sample, born on average in 1923, performed mostly identically. CONCLUSION: This study showed a significant increase of cognitive scores over time. Further, contemporary octogenarians in the later sample performed like septuagenarians in the former sample. These findings might be consistent with the increase in life expectancy and life span in good health. The study highlights the necessity to take into account factors which may contaminate and artificially inflate the age-related differences in favor of younger to the older adults.

Shape abnormalities of the striatum in Alzheimer's disease.

Postmortem studies show pathological changes in the striatum in Alzheimer's disease (AD). Here, we examine the surface of the striatum in AD and assess whether changes of the surface are associated with impaired cognitive functioning. The shape of the striatum (n. accumbens, caudate nucleus, and putamen) was compared between 35 AD patients and 35 individuals without cognitive impairment. The striatum was automatically segmented from 3D T1 magnetic resonance images and automatic shape modeling tools (Growing Adaptive Meshes) were applied for morphometrical analysis. Repeated permutation tests were used to identify locations of consistent shape deformities of the striatal surface in AD. Linear regression models, corrected for age, gender, educational level, head size, and total brain parenchymal volume were used to assess the relation between cognitive performance and local surface deformities. In AD patients, differences of shape were observed on the medial head of the caudate nucleus and on the ventral lateral putamen, but not on the accumbens. The head of the caudate nucleus and ventral lateral putamen are characterized by extensive connections with the orbitofrontal and medial temporal cortices. Severity of cognitive impairment was associated with the degree of deformity of the surfaces of the accumbens, rostral medial caudate nucleus, and ventral lateral putamen. These findings provide evidence for the hypothesis that in AD primarily associative and limbic cerebral networks are affected.

Inflammation and apoptosis genes and the risk of restenosis after percutaneous coronary intervention.

OBJECTIVES: Genetic factors appear to be important in the development of restenosis after percutaneous coronary intervention, as well as in the process of inflammation, a pivotal factor in restenosis. Caspase-1, interleukin-1-receptor and protein tyrosine phosphatase nonreceptor type 22 are important mediators in the inflammatory response and caspase-1 also in apoptosis. Therefore, we examined whether polymorphisms in these candidate genes are related to the risk of developing restenosis after percutaneous coronary intervention. METHODS: The GENetic DEterminants of Restenosis-project is a multicenter prospective follow-up study. The 5352G/A (L235L) caspase-1-polymorphism, the 7464C/G (A124G) interleukin-1r-polymorphism and the 1858C/T (R620W) protein tyrosine phosphatase nonreceptor type 22-polymorphism were genotyped. To examine the functional effect of the caspase-1 polymorphism, mature plasma interleukin-1beta levels were measured by enzyme-linked immunosorbent assay in lipopolysaccharide-stimulated whole blood from a subpopulation of patients. RESULTS: A total of 3104 patients, age 62.1+/-10.7 years, were included after successful percutaneous coronary intervention. A significant association between the 5352AA genotype of the caspase-1 gene and target vessel revascularization (relative risk 2.2, 95% confidence interval 1.32-3.76) was observed after correcting for clinical variables. Angiographic analysis of a subgroup of patients (N=478) also showed an increased risk for developing restenosis for patients having the 5352GA/AA genotype (P=0.001). The results were corroborated, although they were not statistically significant, by somewhat higher mature interleukin-1beta levels in patients with the 5352AA genotype. CONCLUSIONS: The present study shows that patients with the 5352AA genotype in the caspase-1 gene are at increased risk of developing restenosis. If confirmed by other studies, screening patients for this genotype can lead to better risk stratification and provide indications for improving individual treatment; for instance, by providing a new target for drug-eluting stents.