| 1. |
- Palmqvist, Sebastian, et al.
(författare)
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Detailed comparison of amyloid PET and CSF biomarkers for identifying early Alzheimer disease
- 2015
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Ingår i: Neurology. - : Lippincott Williams & Wilkins. - 1526-632X .- 0028-3878. ; 85:14, s. 1240-1249
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Tidskriftsartikel (refereegranskat)abstract
- Objective:To compare the diagnostic accuracy of CSF biomarkers and amyloid PET for diagnosing early-stage Alzheimer disease (AD).Methods:From the prospective, longitudinal BioFINDER study, we included 122 healthy elderly and 34 patients with mild cognitive impairment who developed AD dementia within 3 years (MCI-AD). -Amyloid (A) deposition in 9 brain regions was examined with [F-18]-flutemetamol PET. CSF was analyzed with INNOTEST and EUROIMMUN ELISAs. The results were replicated in 146 controls and 64 patients with MCI-AD from the Alzheimer's Disease Neuroimaging Initiative study.Results:The best CSF measures for identifying MCI-AD were A42/total tau (t-tau) and A42/hyperphosphorylated tau (p-tau) (area under the curve [AUC] 0.93-0.94). The best PET measures performed similarly (AUC 0.92-0.93; anterior cingulate, posterior cingulate/precuneus, and global neocortical uptake). CSF A42/t-tau and A42/p-tau performed better than CSF A42 and A42/40 (AUC difference 0.03-0.12, p < 0.05). Using nonoptimized cutoffs, CSF A42/t-tau had the highest accuracy of all CSF/PET biomarkers (sensitivity 97%, specificity 83%). The combination of CSF and PET was not better than using either biomarker separately.Conclusions:Amyloid PET and CSF biomarkers can identify early AD with high accuracy. There were no differences between the best CSF and PET measures and no improvement when combining them. Regional PET measures were not better than assessing the global A deposition. The results were replicated in an independent cohort using another CSF assay and PET tracer. The choice between CSF and amyloid PET biomarkers for identifying early AD can be based on availability, costs, and doctor/patient preferences since both have equally high diagnostic accuracy.Classification of evidence:This study provides Class III evidence that amyloid PET and CSF biomarkers identify early-stage AD equally accurately.
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| 2. |
- van Westen, Danielle, et al.
(författare)
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Cerebral white matter lesions - associations with A beta isoforms and amyloid PET
- 2016
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 6:20709
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Tidskriftsartikel (refereegranskat)abstract
- Small vessel disease (SVD) and amyloid deposition may promote each other, with a potential association between SVD and altered production or clearance of beta-amyloid (A beta) affecting its cleavage products. We investigated the relationship between SVD, multiple isoforms of A beta in cerebrospinal fluid (CSF) and cortical A beta in 831 subjects with cognitive performance ranging from normal to Alzheimer's disease (AD) (the Swedish BioFINDER study). SVD was estimated as white matter lesions (WML) and lacunes. 18F-flutemetamol PET was performed in 321 subjects. Lower CSF levels of A beta 38 and A beta 40 were consistently associated with increased WML in all subgroups, while lower levels of CSF A beta 42 were associated with WML mainly in AD. CSF A beta 38 and A beta 40 were associated with regional WML in all regions, while CSF A beta 42 was associated with temporal WML only. A composite measure of 18F-flutemetamol uptake was not associated with WML, and regional 18F-flutemetamol uptake only with temporal WML. Lacunes were not associated with A beta isoforms nor 18F-flutemetamol uptake. Our results suggest that WML may be associated with alterations in the production or clearance of A beta species, particularly of A beta 38 and A beta 40. However, in AD cases, A beta 42 pathology might be associated with WML, especially in the temporal lobe.
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| 3. |
- Holm, Hannes, et al.
(författare)
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N-Terminal Prosomatostatin and Risk of Vascular Dementia
- 2017
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Ingår i: Cerebrovascular Diseases. - : S. Karger. - 1015-9770 .- 1421-9786. ; 44:5-6, s. 259-265
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Increased somatostatin plasma concentration has been found in patients with vascular dementia. However, it is unknown whether or not somatostatin levels may predict dementia development in the general population. To this end, we sought to assess the association of circulating N-terminal prosomatostatin (NT-proSST) with incident dementia among community-dwelling older adults.METHODS: In the prospective population-based Malmö Preventive Project, 5,347 study participants (mean age: 69 ± 6years; 70% men) provided plasma for the determination of NT-proSST concentration. Of these, 373 participants (7%) were diagnosed with dementia (120 Alzheimer's disease, 83 vascular, 102 mixed, and 68 other aetiology) during a follow-up period of 4.6 ± 1.3 years. The association of NT-proSST with the risk of dementia and its subtypes was studied using multivariable-adjusted Cox regression models controlling for age, gender, body mass index, systolic blood pressure, antihypertensive treatment, smoking, diabetes, lipid levels and prevalent stroke.RESULTS: Higher levels of NT-proSST were significantly associated with an increased risk of vascular dementia (hazard ratio [HR] per 1 SD: 1.29; 95% CI 1.05-1.59; p = 0.016), whereas no association was observed with Alzheimer's disease (HR per 1 SD: 0.99; 95% CI 0.81-1.20; p = 0.91), all-cause dementia (HR per 1 SD: 1.04; 95% CI 0.94-1.16; p = 0.44), and mixed dementia (HR per 1 SD: 0.98; 95% CI 0.79-1.21; p = 0.84). Levels of NT-proSST above 563 pmol/L (highest quartile) conferred distinctly increased risk of vascular dementia (HR 1.66; 95% CI 1.05-2.63; p = 0.029) compared with lower values.CONCLUSIONS: Higher levels of circulating N-terminal-prosomatostatin are associated with increased incidence of vascular dementia. Our findings might be of importance for the understanding of dementia development in older adults.
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| 4. |
- Janelidze, Shorena, et al.
(författare)
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Increased blood-brain barrier permeability is associated with dementia and diabetes but not amyloid pathology or APOE genotype
- 2017
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Ingår i: Neurobiology of Aging. - : Elsevier BV. - 0197-4580 .- 1558-1497. ; 51, s. 104-112
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Tidskriftsartikel (refereegranskat)abstract
- Blood-brain barrier (BBB) dysfunction might be an important component of many neurodegenerative disorders. In this study, we investigated its role in dementia using large clinical cohorts. The cerebrospinal fluid (CSF)/plasma albumin ratio (Qalb), an indicator of BBB (and blood-CSF barrier) permeability, was measured in a total of 1015 individuals. The ratio was increased in patients with Alzheimer's disease, dementia with Lewy bodies or Parkinson's disease dementia, subcortical vascular dementia, and frontotemporal dementia compared with controls. However, this measure was not changed during preclinical or prodromal Alzheimer's disease and was not associated with amyloid positron emission tomography or APOE genotype. The Qalb was increased in diabetes mellitus and correlated positively with CSF bio-markers of angiogenesis and endothelial dysfunction (vascular endothelial growth factor, intracellular adhesion molecule 1, and vascular cell adhesion molecule 1). In healthy elderly, high body mass index and waist-hip ratio predicted increased Qalb 20 years later. In summary, BBB permeability is increased in major dementia disorders but does not relate to amyloid pathology or APOE genotype. Instead, BBB impairment may be associated with diabetes and brain microvascular damage. (C) 2016 The Authors. Published by Elsevier Inc.
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| 5. |
- Sämgård, Kajsa, et al.
(författare)
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Cerebrospinal fluid total tau as a marker of Alzheimer's disease intensity.
- 2010
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Ingår i: International journal of geriatric psychiatry. - : Wiley. - 1099-1166 .- 0885-6230. ; 25:4, s. 403-10
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this longitudinal study was to test the hypothesis that CSF biomarkers in AD patients also may be forward-looking measures that are associated not only with the degree and profile of cognitive impairment but also with changes in cognition over time.
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| 6. |
- Johansson, Per, 1966, et al.
(författare)
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Mild dementia is associated with increased adrenal secretion of cortisol and precursor sex steroids in women.
- 2011
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Ingår i: Clinical endocrinology. - : Wiley. - 1365-2265 .- 0300-0664. ; 75:3, s. 301-308
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Tidskriftsartikel (refereegranskat)abstract
- Context Sex steroid levels decrease with increasing age, but little is known whether this is of importance for the age-related decline in cognitive function. Design and patients A cross-sectional study of 50 (26 men) consecutive patients under primary evaluation of cognitive impairment (D group) and 18 (9 men) matched healthy controls (C group). Measurements Sex steroid and precursor levels were determined in serum and, when measurable, in cerebrospinal fluid (CSF) using gas chromatography/mass spectroscopy (GC-MS) or liquid chromatography/mass spectroscopy (LC-MS). Sex hormone binding globulin (SHBG) and cortisol concentrations were measured using conventional assays. Results Patients in the D group had higher 24-h urine cortisol levels and increased serum levels of dehydroepiandrosterone (DHEA) and its sulphate ester dihydroepiandrosterone sulphate (DHEAS), androsterone (ADT), and oestrone (E1) and its sulphate ester E1S, compared with the controls. When men and women were analysed separately, increased serum concentrations of E1 and E1S were observed in both D men and D women, whereas increased levels of other sex steroids and cortisol were seen only in D women. Conclusions In both D men and women, serum E1 and E1S levels were increased, whereas other changes were gender specific and only seen in D women. Further studies are needed to determine whether these changes are a cause of, or merely a consequence of, cognitive impairment in elderly subjects.
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| 7. |
- Johansson, Per, et al.
(författare)
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Cerebrospinal Fluid Biomarkers for Alzheimer's Disease: Diagnostic Performance in a Homogeneous Mono-Center Population
- 2011
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Ingår i: Journal of Alzheimer's Disease. - 1387-2877 .- 1875-8908. ; 24:3, s. 537-546
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Tidskriftsartikel (refereegranskat)abstract
- The cerebrospinal fluid (CSF) biomarkers amyloid-beta (A beta)(1-42), T-tau, and P-tau have good diagnostic accuracy for clinically diagnosed Alzheimer's disease (AD). However, in multi-center studies, the predictive values of the CSF biomarkers have been lower, possibly due to differences in procedures for lumbar puncture and CSF handling and storage, and to differences in patient populations, clinical evaluations, and diagnostic procedures. Here we investigate the diagnostic accuracy of CSF biomarkers in a well defined homogeneous mono-center population. We also evaluate an extended panel of amyloid related biomarkers. Sixty consecutive patients admitted for cognitive impairment to a memory clinic were recruited. The participants included patients with AD or mild cognitive impairment (MCI) diagnosed with AD upon follow-up (n = 32), patients with stable MCI (n = 13), patients with other dementias diagnosed at primary evaluation or upon follow-up (n = 15), and healthy controls (n = 20). CSF was analyzed for A beta(1-42), T-tau, P-tau, A beta(X-38), A beta(X-40), A beta(X-42), sA beta PP alpha, and sA beta PP beta. In multivariate analysis, the core biomarkers A beta(1-42), T-tau, and P-tau demonstrated a high ability to diagnose AD versus the combined groups of controls and stable MCI, with an area under the receiver operating characteristic curve (AUROC) of 0.97 (95% CI 0.93-1.00, p < 0.0001). The additional biomarkers only marginally increased AUROC to 0.98 (95% CI 0.95-1.00, p < 0.0001), this increase mainly mediated by A beta(X-42). In conclusion, CSF biomarkers A beta(1-42), T-tau, and P-tau have very high diagnostic accuracy in a well defined cohort of untreated patients, demonstrating the excellent potency of CSF biomarkers to identify pathological processes in AD when a stringent analytical protocol is used.
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| 8. |
- Smith, Ruben, et al.
(författare)
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In vivo retention of (18)F-AV-1451 in corticobasal syndrome.
- 2017
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Ingår i: Neurology. - 1526-632X. ; 89:8, s. 845-853
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Tidskriftsartikel (refereegranskat)abstract
- To study the usefulness of (18)F-AV-1451 PET in patients with corticobasal syndrome (CBS).We recruited 8 patients with CBS, 17 controls, 31 patients with Alzheimer disease (AD), and 11 patients with progressive supranuclear palsy (PSP) from the Swedish BioFINDER study. All patients underwent clinical assessment, (18)F-AV-1451 PET, MRI, and quantification of β-amyloid pathology. A subset of participants also underwent (18)F-FDG-PET.In the 8 patients with CBS, 6 had imaging findings compatible with the corticobasal degeneration pathology and 2 with typical AD pathology. In the 6 patients with CBS without typical AD pathology, there were substantial retentions of (18)F-AV-1451 in the motor cortex, corticospinal tract, and basal ganglia contralateral to the most affected body side. These patients could be clearly distinguished from patients with AD dementia or PSP using (18)F-AV-1451. However, cortical atrophy was more widespread than the cortical retention of (18)F-AV1451 in these CBS cases, and cortical AV-1451 uptake did not correlate with cortical thickness or glucose hypometabolism. These results are in sharp contrast to AD dementia, where (18)F-AV-1451 retention was more widespread than cortical atrophy, and correlated well with cortical thickness and hypometabolism.Patients with CBS without typical AD pathology exhibited AV-1451 retention in the motor cortex, corticospinal tract, and basal ganglia contralateral to the affected body side, clearly different from controls and patients with AD dementia or PSP. However, cortical atrophy measured with MRI and decreased (18)F-fluorodeoxyglucose uptake were more widespread than (18)F-AV-1451 uptake and probably represent earlier, yet less specific, markers of CBS.This study provides Class III evidence that (18)F-AV-1451 PET distinguishes between CBS and AD or PSP.
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| 9. |
- Mattsson, Niklas, et al.
(författare)
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18F-AV-1451 and CSF T-tau and P-tau as biomarkers in Alzheimer's disease
- 2017
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Ingår i: EMBO Molecular Medicine. - : EMBO. - 1757-4676 .- 1757-4684. ; 9, s. 1212-1223
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Tidskriftsartikel (refereegranskat)abstract
- To elucidate the relationship between cerebrospinal fluid (CSF) total-tau (T-tau) and phosphorylated tau (P-tau) with the tau PET ligand 18F-AV-1451 in Alzheimer's disease (AD), we examined 30 cognitively healthy elderly (15 with preclinical AD), 14 prodromal AD, and 39 AD dementia patients. CSF T-tau and P-tau were highly correlated (R = 0.92, P < 0.001), but they were only moderately associated with retention of 18F-AV-1451, and mainly in demented AD patients. 18F-AV-1451, but not CSF T-tau or P-tau, was strongly associated with atrophy and cognitive impairment. CSF tau was increased in preclinical AD, despite normal 18F-AV-1451 retention. However, not all dementia AD patients exhibited increased CSF tau, even though 18F-AV-1451 retention was always increased at this disease stage. We conclude that CSF T-tau and P-tau mainly behave as biomarkers of "disease state", since they appear to be increased in many cases of AD at all disease stages, already before the emergence of tau aggregates. In contrast, 18F-AV-1451 is a biomarker of "disease stage", since it is increased in clinical stages of the disease, and is associated with brain atrophy and cognitive decline.
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| 10. |
- Lindholm, Beata, et al.
(författare)
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The clinical significance of 10-m walk test standardizations in Parkinson’s disease
- 2018
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Ingår i: Journal of Neurology. - : Springer Science and Business Media LLC. - 0340-5354 .- 1432-1459. ; 265:8, s. 1829-1835
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Tidskriftsartikel (refereegranskat)abstract
- Background: The 10-m walk test (10MWT) is a widely used measure of gait speed in Parkinson’s disease (PD). However, it is unclear if different standardizations of its conduct impact test results. Aim of the study: We examined the clinical significance of two aspects of the standardization of the 10MWT in mild PD: static vs. dynamic start, and a single vs. repeated trials. Implications for fall prediction were also explored. Methods: 151 people with PD (mean age and PD duration, 68 and 4 years, respectively) completed the 10MWT in comfortable gait speed with static and dynamic start (two trials each), and gait speed (m/s) was recorded. Participants then registered all prospective falls for 6 months. Results: Absolute mean differences between outcomes from the various test conditions ranged between 0.016 and 0.040 m/s (effect sizes, 0.06–0.14) with high levels of agreement (intra-class correlation coefficients, 0.932–0.987) and small standard errors of measurement (0.032–0.076 m/s). Receiver operating characteristic curves showed similar discriminate abilities for prediction of future falls across conditions (areas under curves, 0.70–0.73). Cut-off points were estimated at 1.1–1.2 m/s. Conclusions: Different 10MWT standardizations yield very similar results, suggesting that there is no practical need for an acceleration distance or repeated trials when conducting this test in mild PD.
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