AbstractBackgroundApolipoprotein E (APOE) ε4 allele's role as a modulator of the relationship between soluble plasma amyloid beta (Aβ) and fibrillar brain Aβ measured by Pittsburgh compound B positron emission tomography ([11C]PiB PET) has not been assessed.MethodsNinety‐six Alzheimer's Disease Neuroimaging Initiative participants with [11C]PiB scans and plasma Aβ1–40 and Aβ1–42 measurements at the time of PET scanning were included. Regional and voxelwise analyses of [11C]PiB data were used to determine the influence of APOE ε4 allele on association of plasma Aβ1–40, Aβ1–42, and Aβ1–40/Aβ1–42 with [11C]PiB uptake.ResultsIn APOE ε4− but not ε4+ participants, positive relationships between plasma Aβ1–40/Aβ1–42 and [11C]PiB uptake were observed. Modeling the interaction of APOE and plasma Aβ1–40/Aβ1–42 improved the explained variance in [11C]PiB binding compared with using APOE and plasma Aβ1–40/Aβ1–42 as separate terms.ConclusionsThe results suggest that plasma Aβ is a potential Alzheimer's disease biomarker and highlight the importance of genetic variation in interpretation of plasma Aβ levels.
O4‐01‐01: Classification of MCI and Alzheimer's disease from CSF biomarkers: An ADNI study of Aß, tau and P‐tau versus 83 proteomic analytes
The role of the Alzheimer's Disease Neuroimaging Initiative Genetics Core is to facilitate the investigation of genetic influences on disease onset and trajectory as reflected in structural, functional, and molecular imaging changes; fluid biomarkers; and cognitive status. Major goals include (1) blood sample processing, genotyping, and dissemination, (2) genome‐wide association studies (GWAS) of longitudinal phenotypic data, and (3) providing a central resource, point of contact and planning group for genetics within the Alzheimer's Disease Neuroimaging Initiative. Genome‐wide array data have been publicly released and updated, and several neuroimaging GWAS have recently been reported examining baseline magnetic resonance imaging measures as quantitative phenotypes. Other preliminary investigations include copy number variation in mild cognitive impairment and Alzheimer's disease and GWAS of baseline cerebrospinal fluid biomarkers and longitudinal changes on magnetic resonance imaging. Blood collection for RNA studies is a new direction. Genetic studies of longitudinal phenotypes hold promise for elucidating disease mechanisms and risk, development of therapeutic strategies, and refining selection criteria for clinical trials.
Intermittent Hemodialysis Versus Continuous Renal Replacement Therapy for Acute Renal Failure in the Intensive Care Unit: An Observational Outcomes Analysis
Background: Studies have failed to show a survival difference between intermittent hemodialysis (IHD) and continuous renal replacement therapy (CRRT). Comparative cost analyses are limited and fail to control for differences in patient disease severity and comorbid conditions. The authors retrospectively estimated clinical and economic outcomes associated with CRRT and IHD among critically ill patients experiencing acute renal failure (ARF) in 2 tertiary care hospitals in Rochester, Minnesota, between January 1, 2000, and December 12, 2001. Methods: 161 critically ill patients requiring dialysis for ARF were analyzed. Patient demo-graphics, comorbid conditions, ARF etiology, mode of renal replacement therapy (RRT), renal recovery, and survival were abstracted from medical chart. APACHE II scores at dialysis initiation were calculated. Administrative data tracked length of stay (LOS) and direct medical costs from initiation of RRT to death or intensive care unit (ICU) and hospital discharge. Multivariate modeling was used to adjust outcomes for baseline differences. Results: 84 (52%) of the patients received CRRT and 77 (48%) received IHD. CRRT-treated patients were younger (58 vs 65 years), less likely male (58% vs 77%), had higher APACHE II scores (32 vs 27) with a higher incidence of sepsis (46% vs 30%) and respiratory disease (56% vs 39%), and were less likely to have chronic renal insufficiency (32% vs 49%). With adjustment for differences in baseline patient characteristics, the RRT method did not affect the likelihood of renal recovery, in-hospital survival, or survival during follow-up. Mean adjusted ICU LOS was 9.5 days shorter for IHD-treated than CRRT-treated patients ( P < .001), and the adjusted mean difference in hospital and total costs associated with ICU stay was $56 564 and $60 827, in favor of IHD ( P < .001). Mean adjusted total costs through hospital discharge were $93 611 and $140 733 among IHD-treated and CRRT-treated patients, respectively ( P < .001). Conclusions: This observational study suggests that costs may significantly differ by mode of RRT despite similar severity-adjusted patient outcomes. Future prospective comparisons of renal replacement modalities will need to include both clinical and economic outcomes.
Gemcitabine, Cisplatin, and Radiotherapy for Patients With Locally Advanced Pancreatic Adenocarcinoma: Results of the North Central Cancer Treatment Group Phase II Study N9942
Purpose A phase II study was conducted to determine the efficacy and toxicity of radiotherapy with concomitant gemcitabine and cisplatin for patients with locally advanced pancreatic adenocarcinoma. Patients and Methods Forty-eight patients with locally advanced pancreatic adenocarcinoma received gemcitabine (30 mg/m2) and cisplatin (10 mg/m2) twice weekly during the first 3 weeks of radiotherapy. The radiation dose to the primary tumor and regional nodes was 45 Gy in 25 fractions, and the gross tumor volume received an additional 5.4 Gy in three fractions. Four weeks after radiotherapy, patients received gemcitabine (1,000 mg/m2) once weekly every 3 of 4 weeks for a 12-week period. The primary end point was survival at 12 months. Secondary end points were time to progression, toxicity, and quality of life. Results Survival at 1 year was 40% for 47 eligible patients. The median survival was 10.2 months. Confirmed responses were observed for 8.5% (two partial, two complete), and median time to progression was 7.3 months. Grade 4 or higher toxicity was observed for 31% and consisted primarily of hematologic and GI toxicity. There was a trend toward improved overall quality of life, measured by the Symptom Distress Scale (P = .06), with significant improvements in domains of insomnia, pain, and outlook. Conclusion The combination of radiotherapy, gemcitabine, and cisplatin was well tolerated. Survival results were similar to those achieved with other treatment regimens for patients with locally advanced pancreatic cancer but did not meet our predefined criteria for additional evaluation of this regimen.