Plasma amyloid-beta oligomer is related to subjective cognitive decline and brain amyloid status.

BACKGROUND: Subjective cognitive decline (SCD) is a target for Alzheimer's disease prediction. Plasma amyloid-beta oligomer (AßO), the pathogenic form of Aß in blood, has recently been proposed as a novel blood-based biomarker of AD prediction by representing brain Aß deposition. The relationship between plasma AßO, brain Aß deposition, and SCD in individuals with normal objective cognition has not been investigated. METHODS: In this cross-sectional study, we analyzed 126 participants with normal objective cognition. More SCD symptoms were expressed as higher scores of the Subjective Cognitive Decline Questionnaire (SCDQ) and Memory Age-associated Complaint Questionnaire (MACQ). The plasma AßO level of each participant was measured twice for validation and expressed as a concentration (ng/mL) and a ratio relative to the mean value of two internal standards. Brain Aß deposition was assessed by [18F] flutemetamol positron emission tomography (PET) and expressed as standard uptake value ratio (SUVR). Associations of SCDQ and MACQ with plasma AßO levels or SUVR were analyzed in multiple linear regression models. The association between plasma AßO level and flutemetamol PET positivity was assessed in logistic regression and receiver operative characteristic analyses. RESULTS: Overall, participants were 73.3 years old with female predominance (69.0%). After adjustment for confounders, high SCDQ and MACQ scores were associated with the high plasma AßO levels as both concentrations and ratios (ratios: standardized coefficient = 0.246 and p = 0.023 for SCDQ, standardized coefficient = 0.209 and p = 0.029 for MACQ; concentrations: standardized coefficient = 0.257 and p = 0.015 for SCDQ, standardized coefficient = 0.217 and p = 0.021 for MACQ). In contrast, SCDQ and MACQ were not significantly associated with SUVRs (p = 0.134 for SCDQ, p = 0.079 for MACQ). High plasma AßO levels were associated with flutemetamol PET (+) with an area under the curve of 0.694 (ratio) or 0.662 (concentration). Combined with APOE e4, plasma AßO presented area under the curves of 0.789 (ratio) and 0.783 (concentration). CONCLUSIONS: Our findings indicate that the high plasma AßO level could serve as a potential surrogate biomarker of severe SCD and the presence of brain Aß deposition in individuals with normal objective cognition.

Effect of drug compliance on health care costs in newly-diagnosed dementia: Analysis of nationwide population-based data.

BACKGROUND: The cost-effectiveness of both cholinesterase inhibitors and memantine by delaying nursing home placement has been supported by numerous studies. The importance of sustained pharmacological treatment in dementia has been relatively less recognized by public health policies compared to early diagnosis. We investigated the effect of the drug (donepezil, rivastigmine, galantamine, and memantine) compliance on the health care costs in newly-diagnosed dementia. METHODS: National Health Insurance Service (NHIS) database which covers the entire population of South Korea was used for analysis. Health care expenditure of patients newly-diagnosed with dementia in between 2012 and 2014 was investigated for 3-5 years. For drug compliance, we used Medication Possession Ratio (MPR) that indicates the percentage of time a patient has access to medication. Multivariate linear regression analysis including generalized estimated equation and gamma distribution was used for statistical analysis. RESULTS: We identified 252,594 patients who were both prescribed with cognitive enhancers and newly diagnosed with dementia. When initial MPR increased 20%, total health care costs decreased 8.4% (RR = 0.916, 95%; CI 0.914 to 0.916). Same relationship was shown with medical costs related to dementia, admission to a general hospital, and emergency room visits. When MPR increased 20% compared to the previous year, the total health care costs, admission to a general hospital, emergency room visits, and admission to a nursing hospital decreased. CONCLUSIONS: This population-based retrospective cohort study provides evidence that patients newly-diagnosed with dementia who showed higher initial drug compliance or maintained antidementia drugs (Cholinesterase inhibitors and memantine) would benefit in total health-care costs.

Development and evaluation of a mobile-optimized daily self-rating depression screening app: A preliminary study.

The aims of this study were to design a mobile app that would record daily self-reported Korean version of the Center for Epidemiologic Studies Depression Scale-Revised (K-CESD-R) ratings in a "Yes" or "No" format, develop two different algorithms for converting mobile K-CESD-R scores in a binary format into scores in a 5-point response format, and determine which algorithm would be more appropriately applied to the newly developed app. Algorithm (A) was designed to improve the scoring system of the 2-week delayed retrospective recall-based original K-CESD-R scale, and algorithm (B) was designed to further refine the scoring of the 24-hour delayed prospective recall-based mobile K-CESD-R scale applied with algorithm (A). To calculate total mobile K-CESD-R scores, each algorithm applied certain cut-off criteria for a 5-point scale with different inter-point intervals, defined by the ratio of the total number of times that users responded "Yes" to each item to the number of days that users reported daily depressive symptom ratings during the 2-week study period. Twenty participants were asked to complete a K-CESD-R Mobile assessment daily for 2 weeks and an original K-CESD-R assessment delivered to their e-mail accounts at the end of the 2-week study period. There was a significant difference between original and mobile algorithm (B) scores but not between original and mobile algorithm (A) scores. Of the 20 participants, 4 scored at or above the cut-off criterion (≥13) on either the original K-CESD-R (n = 4) or the mobile K-CESD-R converted with algorithm (A) (n = 3) or algorithm (B) (n = 1). However, all participants were assessed as being below threshold for a diagnosis of a mental disorder during a clinician-administered diagnostic interview. Therefore, the K-CESD-R Mobile app using algorithm (B) could be a more potential candidate for a depression screening tool than the K-CESD-R Mobile app using algorithm (A).

Delirium characteristics and outcomes in medical and surgical lnpatients: A subgroup analysis.

PURPOSE: Persistent delirium can negatively affect patients, increase healthcare costs, and extend the length of hospital stays. This investigation was undertaken to explore associations between patient characteristics and delirium outcomes. MATERIALS AND METHODS: Intensive care unit (ICU) and medical and surgical ward inpatients for whom psychiatric consultation was requested for delirium were included in this study. Delirium screening and ongoing assessments were conducted using the Confusion Assessment Method for ICU patients. RESULTS: Postoperative delirium developing as a secondary complication following surgery was found to be of significantly longer duration and associated with greater length of hospitalization compared with postoperative delirium attributable to surgery and delirium in medical patients. Medical patients with delirium had lower delirium recovery rates at discharge compared with surgical patients. CONCLUSIONS: The findings that patient type and timing of postoperative delirium are associated with differential delirium outcomes suggest that targeted screening and intervention approaches may be needed. Medical patients were more likely to be discharged before recovery from delirium compared with surgical patients. Differences in underlying chronic medical conditions may account for the observed differences in discharge condition between medical and surgical patients with delirium.