Citations

AbstractIntroductionMedial temporal lobe (MTL) uptake on tau–positron emission tomography (PET) is seen not only in Alzheimer's disease (AD) dementia but also in the aging population. The relationship of these findings to the development of AD dementia needs to be better understood.MethodsTau‐PET with AV‐1451 was performed on 576 cognitively unimpaired (CU) participants aged 50–94 years. The number of CUs with and without abnormal MTL regions and those with or without extra‐MTL abnormalities was determined. Left and right regions were compared within each subject.ResultsOf CUs, 58% (334/576) had abnormal tau‐PET findings. MTL abnormalities were present in 41% (238/576) of subjects.DiscussionMTL tau‐PET signal is often associated with abnormal extra‐MTL tau‐PET signal in CU participants and may represent neurofibrillary tangle development that could identify participants most likely to develop AD dementia. Tau‐PET signal exclusively outside of the MTL is seen in 17% of CU participants and could be the initial findings in participants in different AD dementia pathways. Significant (P < .001) differences in tau–standardized uptake value ratio between sides were noted in 26 of 41 examined brain regions implicating further study of side‐specific deficits.

AbstractThe relationship between clinicopathologic diagnosis and 123I‐FP‐CIT SPECT in 18 patients with dementia (12 with Lewy body disease) from one center in the United States was assessed. The sensitivity and specificity of abnormal 123I‐FP‐CIT SPECT with reduced striatal uptake on visual inspection for predicting Lewy body disease were 91.7% and 83.3%, respectively. The mean calculated putamen to occipital ratio (mPOR) based on regions of interest was significantly reduced in Lewy body disease compared to non‐Lewy body disease cases (P = 0.002). In this study, abnormal 123I‐FP‐CIT SPECT was strongly associated with underlying Lewy body disease pathology, supporting the utility of 123I‐FP‐CIT SPECT in the clinical diagnosis of dementia with Lewy bodies.

ObjectiveTo use a cluster analysis of [18F]AV‐1451 tau‐PET data to determine how subjects with Alzheimer's disease (AD) vary in the relative involvement of the entorhinal cortex and neocortex, and determine whether relative involvement of these two regions can help explain variability in age and clinical phenotype in AD.MethodsWe calculated [18F]AV‐1451 uptake in entorhinal cortex and neocortex in 62 amyloid‐positive AD patients (39 typical and 23 atypical presentation). tau‐PET (positron emission tomography) values were normalized to the cerebellum to create standard uptake value ratios (SUVRs). tau‐PET SUVRs were log‐transformed and clustered blinded to clinical information into three groups using K‐median cluster analysis. Demographics, clinical phenotype, cognitive performance, and apolipoprotein e4 frequency were compared across clusters.ResultsThe cluster analysis identified a cluster with low entorhinal and cortical uptake (ELo/CLo), one with low entorhinal but high cortical uptake (ELo/CHi), and one with high cortical and entorhinal uptake (EHi/CHi). Clinical phenotype differed across clusters, with typical AD most commonly observed in the ELo/CLo and EHi/CHi clusters, and atypical AD most commonly observed in the ELo/CHi cluster. The ELo/CLo cluster had an older age at PET and onset than the other clusters. Apolipoprotein e4 frequency was lower in the ELo/CHi cluster. The EHi/CHi cluster had the worst memory impairment, whereas the ELo/CHi cluster had the worst impairment in nonmemory domains.InterpretationThis study demonstrates considerable variability in [18F]AV‐1451 tau‐PET uptake in AD, but shows that a straightforward clustering based on entorhinal and cortical uptake maps well onto age and clinical presentation in AD. Ann Neurol 2018 Ann Neurol 2018;83:248–257

Objectives: Low serum albumin levels (hypoalbuminemia) have classically been used to identify malnutrition. The effect of increasing severity of malnutrition on postoperative outcomes in patients undergoing hip fracture surgery has not been well delineated on a large scale. Design: Retrospective. Setting: Multicenter. Patient/Participants: A total of 12,373 patients undergoing hip fracture surgery from 2006 to 2013 National Surgery Quality Improvement Project data were identified. Intervention: Patient demographic, comorbidity, and preoperative laboratory data and complication, reoperation, and readmission data were collected. Main Outcome Measurements: Multivariate logistic regression was used to determine the effect of increasing severity of malnutrition on rates of 30-day postoperative complications, readmissions, and reoperations. Results: A total of 12,373 hip fractures met inclusion criteria. A total of 6506 (52.6%) patients had normal albumin levels (albumin ≥3.5 g/dL), 3205 (25.9%) patients were mildly malnourished (albumin 3.1–3.49 g/dL), 2265 (18.3%) were moderately malnourished (albumin 2.4–3.1 g/dL), and 397 (3.2%) patients were severely malnourished (albumin <2.4 g/dL). Mean age was similar between the 4 cohorts (P < 0.001). Severe malnutrition was associated with a 2-fold increase in the odds of postoperative complications and mortality when compared with mild malnutrition (P < 0.001). Increasing severity of malnutrition was associated with significantly longer lengths of stay and higher odds of experiencing a related readmission (P < 0.001). Conclusions: Increasing severity of hypoalbuminemia is independently associated with poorer outcomes in the 30 days after hip fracture surgery. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Background and Purpose— Superficial siderosis (SS) is characterized by hemosiderin deposition in the superficial layers of the central nervous system and can be seen during postmortem examination or with iron-sensitive magnetic resonance imaging techniques. The distribution of SS may predict the probable underlying cause. This study aimed to report the prevalence and natural history of SS in a population-based study. Methods— Brain magnetic resonance imaging scans from the MCSA (Mayo Clinic Study of Aging), a population-based study of residents 50 to 89 years of age in Olmsted County, Minnesota, were reviewed. Participants with imaging consistent with SS were identified from 2011 through 2016. An inverse probability weighting approach was used to convert our observed frequencies to population prevalence of SS. Additional data abstracted included amyloid positron emission tomography, Apolipoprotein E genotype, coexisting cerebral microbleeds, and extent of SS. Results— A total of 1412 participants had eligible magnetic resonance imaging scans. Two participants had infratentorial SS, restricted to the posterior fossa. Thirteen participants had cortical SS involving the cerebral convexities (7 focal and 6 disseminated). Only 3 of the participants with cortical SS (23%) also had cerebral microbleeds. The population prevalence of SS was 0.21% (95% confidence interval, 0–0.45) in those 50 to 69 years old and 1.43% (confidence interval, 0.53–2.34) in those over 69 years old. Apolipoprotein E ε2 allele was more common in those with SS (57.1% versus 15.0%; P <0.001). Compared with participants without SS, those with SS were also more likely to have a positive amyloid positron emission tomographic scan (76.9% versus 29.8%; P <0.001). Conclusions— SS may be encountered in the general elderly population. The association with increased amyloid burden and Apolipoprotein E ε2 genotype supports cerebral amyloid angiopathy as the most common mechanism. Longitudinal follow-up is needed to evaluate the risk of subsequent hemorrhage in cases of incidentally discovered SS.