Detection of Bacterial Neutral Ceramidase in Diabetic Foot Ulcers with an Optimized Substrate and Chemoenzymatic Probes.

Ceramidases (CDases) are important in controlling skin barrier integrity by regulating ceramide composition and affording downstream signal molecules. While the functions of epidermal CDases are known, roles of neutral CDases secreted by skin-residing microbes are undefined. Here, we developed a one-step fluorogenic substrate, S-B, for specific detection of bacterial CDase activity and inhibitor screening. We identified a non-hydrolyzable substrate mimic, C6, as the best hit. Based on C6, we designed a photoaffinity probe, JX-1, which efficiently detects bacterial CDases. Using JX-1, we identified endogenous low-abundance PaCDase in a P. aeruginosa monoculture and in a mixed skin bacteria culture. Harnessing both S-B and JX-1, we found that CDase activity positively correlates with the relative abundance of P. aeruginosa and is negatively associated with wound area reduction in clinical diabetic foot ulcer patient samples. Overall, our study demonstrates that bacterial CDases are important regulators of skin ceramides and potentially play a role in wound healing.

Primary Care Prognostic (PCP) Index of 11-Year Mortality Risk: Development and Validation of a Brief Prognostic Tool.

BACKGROUND: Healthcare providers use a life expectancy of at least 5 to 10 years in shared clinical decision-making with older adults about cancer screening, major surgeries, and disease prevention interventions. At present, few prognostic indexes predict long-term mortality beyond 10 years or are suited for use in primary care settings. OBJECTIVE: We developed and validated an 8-item multidimensional index predicting 11-year mortality for use in primary care. DESIGN, SETTING, AND PARTICIPANTS: Using data from the Singapore Longitudinal Ageing Studies (SLAS), we developed a Primary Care Prognostic (PCP) Index for predicting 11-year mortality risk in a development cohort (n = 1550) and validated it in a geographically different cohort (n = 928). MAIN MEASURES: The PCP Index was derived from eight indicators (body mass loss, weakness, slow gait, comorbidity, polypharmacy, IADL/BADL dependency, low albumin, low total cholesterol, out of 25 candidate indicators) using stepwise Cox proportional hazard models. KEY RESULTS: In the developmental cohort, the mortality hazard ratio increased by 53% per PCP point score increase, independent of age and sex. Across risk categories, absolute risks of mortality increased from 5% (score 0) to 67.9% (scores 7-9), with area under curve (AUC = 0.77 (95% CI 0.73-0.80)). The PCP Index also predicted mortality in the validation cohort, with AUC = 0.70 (95% CI 0.64-0.75). CONCLUSIONS: The PCP Index using simple clinical assessments and point scoring is a potentially useful prognostic tool for predicting long-term mortality and is well suited for risk stratification and shared clinical decision-making with older adults in primary care.

Seeking healthcare services post-stroke: a qualitative descriptive study exploring family caregiver and stroke survivor perspectives in an asian setting.

AIM: Exploration of the healthcare journey post-stroke is incomplete without acknowledging the crucial role of family caregivers. With limited literature documenting the role of caregivers in the healthcare journey post-stroke, we aimed to describe the healthcare experiences of family caregivers and stroke survivors across different caregiver identities in Singapore. METHODS: We conducted a qualitative descriptive study involving semi-structured interviews with transcripts analysed using thematic analysis. 26 stroke survivors and 35 family caregivers purposively sampled from multiple settings. RESULTS: Findings were summarized into seeking care and experience of healthcare encounters. Seeking care comprised of the following themes: factors influencing seeking care, decision to seek care and role of caregiver in seeking care. Experience of healthcare encounters comprised of the following themes: service around the patient, service with care and role of caregiver in healthcare encounters. CONCLUSION: Multi-dimensional role of caregivers in healthcare experience emerged as a major finding. Unique to our Asian context, as per the participants' accounts, family caregivers seemed to be central in healthcare decision-making for stroke survivors, with adult-child caregivers commonly reported being engaged in collaborative decision-making. While spousal caregivers preferred a relational healthcare experience, adult-child caregivers preferred a transactional one. Practical implications include equipping caregivers with skillset to make healthcare decisions, provision of supportive decision-making environment for caregivers and reinforcing communication aspects in the medical, nursing and allied healthcare curriculum to improve healthcare experience.

Support system diversity among family caregivers of stroke survivors: a qualitative study exploring Asian perspectives.

BACKGROUND: Caregiving is a global phenomenon which is bound to increase in tandem with the aging population worldwide. Stroke is a condition common in older people that requires complex caregiving necessitating provision of adequate support to the caregivers. Past literature consists of limited accounts of types and organization of support arrangements needed by different caregivers. We aimed to describe the support system of caregivers of stroke survivors in Singapore, highlighting differences across the different caregiver identities (i.e. spouse, adult-child, etc.). METHODS: We conducted a qualitative descriptive study in the community setting involving 61 purposively sampled and recruited stroke survivors and caregivers. Semi-structured interviews were conducted, and transcripts were analysed using thematic analysis. RESULTS: Our findings were summarized across the following 4 themes: 1) cultural influence and caregiving; 2) caregiver support system with the following sub-themes: 2.1) dyadic caregiver support type, 2.2) extended caregiver support type, 2.3.) distributed caregiver support type and 2.4) empowering caregiver support type; 3) breaks in care of stroke survivor and 4) complex relationship dynamics. We operationalized the caregiver support system as comprising of type, people and activities that enable the caregiver to participate in caregiving activities sustainably. While spouse caregivers preferred dyadic and extended support systems positioning themselves in a more central caregiving role, adult-child caregivers preferred distributed support system involving family members with paid caregivers playing a more central role. CONCLUSIONS: Our findings highlight caregiver identity as a surrogate for the differences in the caregiver support systems. Practical implications include imparting relationship-building skills to the stroke survivor-caregiver dyads to sustain dyadic support system and educating clinicians to include differences in caregiving arrangements of stroke survivors in practising family-centred care.

Burden of informal care in stroke survivors and its determinants: a prospective observational study in an Asian setting.

BACKGROUND: Informal caregiving is an integral part of post-stroke recovery with strenuous caregiving demands often resulting in caregiving burden, threatening sustainability of caregiving and potentially impacting stroke survivor's outcomes. Our study aimed to examine and quantify objective and subjective informal care burden after stroke; and to explore the factors associated with informal care burden in Singapore. METHODS: Stroke patients and their informal caregivers were recruited from all five tertiary hospitals in Singapore from December 2010 to September 2013. Informal care comprised of assistance provided by informal caregivers with any of the activities of daily living. Informal care burden was measured by patients' likelihood of requiring informal care, hours of informal care required, and informal caregivers' Zarit's Burden Score. We examined informal care burden at 3-months and 12-months post-stroke. Generalized linear regressions were applied with control variables including patients' and informal caregivers' demographic characteristics, arrangement of informal care, and patients' health status including stroke severity (measured using National Institute of Health Stroke Scale), functional status (measured using Modified Rankin Scale), self-reported depression, and common comorbidities. RESULTS: Three hundred and five patients and 263 patients were examined at 3-months and 12-months. Around 35% were female and 60% were Chinese. Sixty three percent and 49% of the patients required informal care at 3-months and 12-months point, respectively. Among those who required informal care, average hours required per week were 64.3 h at 3-months and 76.6 h at 12-months point. Patients with higher functional dependency were more likely to require informal care at both time points, and required more hours of informal care at 3-months point. Female informal caregivers and those caring for patients with higher functional dependency reported higher Zarit's Burden. While informal caregivers who worked full-time reported higher burden, those caring for married stroke patients reported lower burden at 3-months point. Informal caregivers who co-cared with foreign domestic workers, i.e.: stay-in migrant female waged domestic workers, reported lower burden. CONCLUSIONS: Informal care burden remains high up to 12-months post-stroke. Factors such as functional dependency, stroke severity, informal caregiver gender and co-caring with foreign domestic workers were associated with informal care burden.

Role of caregiver factors in outpatient medical follow-up post-stroke: observational study in Singapore.

BACKGROUND: Outpatient medical follow-up post-stroke is not only crucial for secondary prevention but is also associated with a reduced risk of rehospitalization. However, being voluntary and non-urgent, it is potentially determined by both healthcare needs and the socio-demographic context of stroke survivor-caregiver dyads. Therefore, we aimed to examine the role of caregiver factors in outpatient medical follow-up (primary care (PC) and specialist outpatient care (SOC)) post-stroke. METHOD: Stroke survivors and caregivers from the Singapore Stroke Study, a prospective, yearlong, observational study, contributed to the study sample. Participants were interviewed 3-monthly for data collection. Counts of PC and SOC visits were extracted from the National Claims Database. Poisson modelling was used to explore the association of caregiver (and patient) factors with PC/SOC visits over 0-3 months (early) and 4-12 months (late) post-stroke. RESULTS: For the current analysis, 256 stroke survivors and caregivers were included. While caregiver-reported memory problems of a stroke survivor (IRR: 0.954; 95% CI: 0.919, 0.990) and caregiver burden (IRR: 0.976; 95% CI: 0.959, 0.993) were significantly associated with lower early post-stroke PC visits, co-residing caregiver (IRR: 1.576; 95% CI: 1.040, 2.389) and negative care management strategies (IRR: 1.033; 95% CI: 1.005, 1.061) were significantly associated with higher late post-stroke SOC visits. CONCLUSION: We demonstrated that the association of caregiver factors with outpatient medical follow-up varied by the type of service (i.e., PC versus SOC) and temporally. Our results support family-centred care provision by family physicians viewing caregivers not only as facilitators of care in the community but also as active members of the care team and as clients requiring care and regular assessments.

Dyadic approach to post-stroke hospitalizations: role of caregiver and patient characteristics.

AIM: To study the association of caregiver factors and stroke patient factors with rehospitalizations over the first 3 months and subsequent 3-12 months post-stroke in Singapore. METHODS: Patients with stroke and their caregivers were recruited in the Singapore Stroke Study, a prospective yearlong cohort. While caregiver and patient variables were taken from this study, hospitalization data were extracted from the national claims database. We used Poisson modelling to perform bivariate and multivariable analysis with counts of hospitalization as the outcome. RESULTS: Two hundred and fifty-six patient with stroke and caregiver dyads (N = 512) were analysed, with patients having spouse (60%), child (29%), sibling (4%) and other (7%) as their caregivers. Among all participants, 89% of index strokes were ischemic, 57% were mild in severity and more than half (59%) of the patients had moderate or severe disability post-stroke as measured on the Modified Rankin Scale. Having social support in the form of a foreign domestic worker for general help of caregiver reduced the hospitalization rate over 3 months post-stroke by 66% (IRR: 0.342; 95% CI: 0.180, 0.651). Compared to having a spousal caregiver, those with a child caregiver had an almost three times greater rate of hospitalizations over 3-12 months post-stroke (IRR: 2.896; 95% CI: 1.399, 5.992). Higher reported caregiving burden at the 3-month point was associated with the higher subsequent rate of hospitalization. CONCLUSION: Recommendations include the adoption of a dyadic or holistic approach to post-stroke care provision by healthcare practitioners, giving due importance to both patients with stroke and their caregivers, integrating caregivers in the healthcare system to extend the care continuum to include informal care in the community and provision of timely support for caregivers.

Influence of cerebrovascular disease on brain networks in prodromal and clinical Alzheimer's disease.

Network-sensitive neuroimaging methods have been used to characterize large-scale brain network degeneration in Alzheimer's disease and its prodrome. However, few studies have investigated the combined effect of Alzheimer's disease and cerebrovascular disease on brain network degeneration. Our study sought to examine the intrinsic functional connectivity and structural covariance network changes in 235 prodromal and clinical Alzheimer's disease patients with and without cerebrovascular disease. We focused particularly on two higher-order cognitive networks-the default mode network and the executive control network. We found divergent functional connectivity and structural covariance patterns in Alzheimer's disease patients with and without cerebrovascular disease. Alzheimer's disease patients without cerebrovascular disease, but not Alzheimer's disease patients with cerebrovascular disease, showed reductions in posterior default mode network functional connectivity. By comparison, while both groups exhibited parietal reductions in executive control network functional connectivity, only Alzheimer's disease patients with cerebrovascular disease showed increases in frontal executive control network connectivity. Importantly, these distinct executive control network changes were recapitulated in prodromal Alzheimer's disease patients with and without cerebrovascular disease. Across Alzheimer's disease patients with and without cerebrovascular disease, higher default mode network functional connectivity z-scores correlated with greater hippocampal volumes while higher executive control network functional connectivity z-scores correlated with greater white matter changes. In parallel, only Alzheimer's disease patients without cerebrovascular disease showed increased default mode network structural covariance, while only Alzheimer's disease patients with cerebrovascular disease showed increased executive control network structural covariance compared to controls. Our findings demonstrate the differential neural network structural and functional changes in Alzheimer's disease with and without cerebrovascular disease, suggesting that the underlying pathology of Alzheimer's disease patients with cerebrovascular disease might differ from those without cerebrovascular disease and reflect a combination of more severe cerebrovascular disease and less severe Alzheimer's disease network degeneration phenotype.

Global cerebrovascular burden and long-term clinical outcomes in Asian elderly across the spectrum of cognitive impairment.

ABSTRACTBackground/Aim:To investigate the predictive ability of the previously established global cerebrovascular disease (CeVD) burden scale on long-term clinical outcomes in a longitudinal study of Asian elderly participants across the spectrum of cognitive impairment. METHODS: A case-control study was conducted over a 2-year period involving participants with no cognitive impairment, cognitive impairment-no dementia (CIND), and Alzheimer's disease (AD). Annually, cognitive function was assessed with a comprehensive neuropsychological battery and the clinical dementia rating (CDR) scale was used to stage disease severity. RESULTS: Of 314 participants, 102 had none/very mild CeVD, 31 mild CeVD, 94 moderate CeVD, and 87 severe CeVD at baseline. There was a 1.14 and 1.42 units decline per year on global cognitive z-scores in moderate and severe CeVD groups, respectively, compared to none/very mild CeVD. Moderate-severe CeVD predicted significant functional deterioration at year 2 (HR = 2.0, 95% CI = 1.2-3.4), and conversion to AD (HR = 6.3, 95% CI = 1.7-22.5), independent of medial temporal atrophy. CONCLUSION: The global CeVD burden scale predicts poor long-term clinical outcome independent of neurodegenerative markers. Furthermore, CeVD severity affects the rate of cognitive and functional deterioration. Hence, cerebrovascular burden, which is potentially preventable, is a strong prognostic indicator, both at preclinical and clinical stages of AD, independent of neurodegenerative processes.

Healthcare utilization and cost trajectories post-stroke: role of caregiver and stroke factors.

BACKGROUND: It is essential to study post-stroke healthcare utilization trajectories from a stroke patient caregiver dyadic perspective to improve healthcare delivery, practices and eventually improve long-term outcomes for stroke patients. However, literature addressing this area is currently limited. Addressing this gap, our study described the trajectory of healthcare service utilization by stroke patients and associated costs over 1-year post-stroke and examined the association with caregiver identity and clinical stroke factors. METHODS: Patient and caregiver variables were obtained from a prospective cohort, while healthcare data was obtained from the national claims database. Generalized estimating equation approach was used to get the population average estimates of healthcare utilization and cost trend across 4 quarters post-stroke. RESULTS: Five hundred ninety-two stroke patient and caregiver dyads were available for current analysis. The highest utilization occurred in the first quarter post-stroke across all service types and decreased with time. The incidence rate ratio (IRR) of hospitalization decreased by 51, 40, 11 and 1% for patients having spouse, sibling, child and others as caregivers respectively when compared with not having a caregiver (p = 0.017). Disability level modified the specialist outpatient clinic usage trajectory with increasing difference between mildly and severely disabled sub-groups across quarters. Stroke type and severity modified the primary care cost trajectory with expected cost estimates differing across second to fourth quarters for moderately-severe ischemic (IRR: 1.67, 1.74, 1.64; p = 0.003), moderately-severe non-ischemic (IRR: 1.61, 3.15, 2.44; p = 0.001) and severe non-ischemic (IRR: 2.18, 4.92, 4.77; p = 0.032) subgroups respectively, compared to first quarter. CONCLUSION: Highlighting the quarterly variations, we reported distinct utilization trajectories across subgroups based on clinical characteristics. Caregiver availability reducing hospitalization supports revisiting caregiver's role as potential hidden workforce, incentivizing their efforts by designing socially inclusive bundled payment models for post-acute stroke care and adopting family-centered clinical care practices.

Can caregivers report their care recipients' post-stroke hospitalizations and outpatient visits accurately? Findings of an Asian prospective stroke cohort.

BACKGROUND: Health services research aimed at understanding service use and improving resource allocation often relies on collecting subjectively reported or proxy-reported healthcare service utilization (HSU) data. It is important to know the discrepancies in such self or proxy reports, as they have significant financial and policy implications. In high-dependency populations, such as stroke survivors, with varying levels of cognitive impairment and dysphasia, caregivers are often potential sources of stroke survivors' HSU information. Most of the work conducted on agreement analysis to date has focused on validating different sources of self-reported data, with few studies exploring the validity of caregiver-reported data. Addressing this gap, our study aimed to quantify the agreement across the caregiver-reported and national claims-based HSU of stroke patients. METHODS: A prospective study comprising multi-ethnic stroke patient and caregiver dyads (N = 485) in Singapore was the basis of the current analysis, which used linked national claims records. Caregiver-reported health services data were collected via face-to-face and telephone interviews, and similar health services data were extracted from the national claims records. The main outcome variable was the modified intraclass correlation coefficient (ICC), which provided the level of agreement across both data sources. We further identified the amount of over- or under-reporting by caregivers across different service types. RESULTS: We observed variations in agreement for different health services, with agreement across caregiver reports and national claims records being the highest for outpatient visits (specialist and primary care), followed by hospitalizations and emergency department visits. Interestingly, caregivers over-reported hospitalizations by approximately 49% and under-reported specialist and primary care visits by approximately 20 to 30%. CONCLUSIONS: The accuracy of the caregiver-reported HSU of stroke patients varies across different service types. Relatively more objective data sources, such as national claims records, should be considered as a first choice for quantifying health care usage before considering caregiver-reported usage. Caregiver-reported outpatient service use was relatively more accurate than inpatient service use over shorter recall periods. Therefore, in situations where objective data sources are limited, caregiver-reported outpatient information can be considered for low volumes of healthcare consumption, using an appropriate correction to account for potential under-reporting.

Caregivers: Do They Make a Difference to Patient Recovery in Subacute Stroke?

OBJECTIVE: To evaluate the relationship between caregiver nature and availability, and rehabilitation outcomes in subacute stroke. DESIGN: Retrospective cohort study. SETTING: Four community rehabilitation hospitals. PARTICIPANTS: Patients with subacute, first-time stroke (N=4042; 48.5% men; mean age ± SD, 70.12±10.4y; 51.5% women; mean age ± SD, 72.54 ±10.0y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Rehabilitation effectiveness, defined as the percentage of potential improvement eventually achieved with rehabilitation; and rehabilitation efficiency, defined as the rate of functional improvement during rehabilitation. RESULTS: In our cohort, 96.7% had available caregiver(s), of which 42.0% were primarily supported by foreign domestic workers (FDWs), 25.9% by spouses, 19.3% by first-degree relatives, 7.8% by other relatives, and 5.1% by other caregivers. Using quantile regression, we found that having a caregiver was independently associated with rehabilitation efficiency (ß=-3.83; 95% confidence interval [CI], -6.99 to -0.66; P=.018). The relationship between caregiver availability and rehabilitation effectiveness was modified by patient sex in that the negative association was significantly greater in men (ß=-22.81; 95% CI, -32.70 to -12.94; P<.001) than women (ß=-5.64; 95% CI, -14.72 to 3.44; P=.223). Having a FDW as a caregiver compared with a spousal caregiver was negatively associated with rehabilitation effectiveness (ß=-3.95; 95% CI, -6.94 to -0.95; P=.01) and rehabilitation efficiency (ß=-1.83; 95% CI, -3.14 to -0.53; P=.006). The number of potential caregivers was only significantly associated with rehabilitation effectiveness at the bivariate level (P=.006). CONCLUSIONS: Caregiver identity, and possibly availability, appears to negatively affect rehabilitation outcomes in subacute stroke. A better understanding of these relationships has potential implications on clinical practice and policy directions.

Rehabilitation Outcomes After Inpatient Rehabilitation for Lower Extremity Amputations in Patients With Diabetes.

OBJECTIVE: To identify factors associated with functional gain, discharge destination, and long-term survival after inpatient rehabilitation in patients with lower extremity amputation and diabetes. DESIGN: Retrospective medical records review. SETTING: All community hospitals. PARTICIPANTS: Patients with diabetes (N=256) admitted for inpatient rehabilitation after lower extremity amputation. INTERVENTIONS: Not applicable. MAIN OUTCOMES MEASURES: Absolute functional gain (AFG) using the Shah-modified Barthel Index, discharge destination, and long-term survival for each patient. RESULTS: Length of stay (B=.15; 95% confidence interval [CI], .08-.21; P<.001) and admission functional status (B=-.09; 95% CI, -.18 to -.01; P=.032) were significantly associated with AFG. Availability of caregiver (foreign domestic worker: odds ratio [OR], 16.39; 95% CI, 4.65-57.78; P<.001; child: OR, 3.82; 95% CI, 1.31-11.12; P=.014; spouse: OR, 2.82; 95% CI, 1.07-7.46; P=.037 vs none), Charlson Comorbidity Index of 1 (OR, 4.32; 95% CI, 1.34-13.93; P=.014 vs ≥4), and younger age (OR, .96; 95% CI, .93-.99; P=.02) were significantly associated with being discharged home. Admission functional status (hazard ratio [HR], .98; 95% CI, .97-.99; P<.001), AFG (HR, .99; 95% CI, 0.97-1.00; P=.058), Charlson Comorbidity Index (1 vs ≥4: HR, .42; 95% CI, .24-.77; P=.004), ischemic heart disease (HR, 2.25; 95% CI, 1.27-4.00; P=.006), discharge destination (other vs home: HR, 1.82; 95% CI, 1.02-3.23; P=.041), age (HR, 1.02; 95% CI, 1.00-1.03; P=.082), and ethnicity (Malay vs Chinese: HR, .37; 95% CI, .16-.87; P=.022) predicted survival postamputation. CONCLUSIONS: Admission functional status predicted both functional gain during rehabilitation and survival in these patients. We also found ethnic differences in outcomes, with Malays having better survival after amputation. Lastly, there appears to be greater reliance on foreign domestic workers as caregivers, with patients with foreign domestic workers as their primary caregiver having the highest odds of being discharged home.

Factors and trade-offs with rehabilitation effectiveness and efficiency in newly disabled older persons.

OBJECTIVE: To determine the factors for rehabilitation effectiveness (REs) and rehabilitation efficiency (REy) among newly disabled older persons and if there is any trade-off between REs and REy. DESIGN: Retrospective cohort study. SETTING: Rehabilitation hospitals. PARTICIPANTS: Patients (N=8828) aged ≥65 years admitted for inpatient rehabilitation from 1996 to 2005. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Independent factors affecting REs and REy were determined. The median rank ratios of REs to REy for each admission Barthel Index (BI) unit and number of days of stay were generated. The ideal ranges of admission BI score and length of stay (LOS) that corresponded to the REs to REy median rank ratio of 1 (both REs and REy optimized) were identified. RESULTS: Factors associated with poorer REs and REy were older age, Malay ethnicity, delayed admission, admission diagnosis of amputation, and comorbidities of dementia and stroke. An increase of 10 in admission BI score was associated with an increase of 3.47% in REs but a decrease of 1.1 per 30 days in REy; and an increase in LOS of 2.7 days was associated with an increase of 28% in REs but a decrease of 5.2 per 30 days in REy. A trade-off relation between REs and REy with respect to admission functional status and LOS was observed. The range, which optimized both REs and REy, was 50 to 59 units for admission BI score and 37 to 46 days for LOS. CONCLUSIONS: There are trade-offs between REs and REy with respect to admission functional status and LOS. Clinicians, policymakers, patients, and other stakeholders should be aware of such trade-offs when they make joint policy decisions about rehabilitation services.

Serum Placental Growth Factor as a Marker of Cerebrovascular Disease Burden in Alzheimer's Disease.

BACKGROUND: Concomitant cerebrovascular diseases (CeVD) have been identified as an important determinant of Alzheimer's disease (AD) progression. Development of robust blood-based biomarkers will provide critical tools to evaluate prognosis and potential interventional strategies for AD with CeVD. OBJECTIVE: This study investigated circulating placental growth factor (PlGF), a potent pro-angiogenic factor related to endothelial dysfunction and vascular inflammation, in an Asian memory clinic cohort of non-demented individuals as well as AD, including its associations with neuroimaging markers of CeVD. METHODS: 109 patients with AD, 76 cognitively impaired with no dementia (CIND), and 56 non-cognitively impaired (NCI) were included in this cross-sectional study. All subjects underwent 3T brain magnetic resonance imaging to assess white matter hyperintensities (WMH), lacunes, cortical infarcts, and cerebral microbleeds (CMBs). Serum PlGF concentrations were measured by electrochemiluminescence immunoassays. RESULTS: Serum PlGF was elevated in AD, but not CIND, compared to the NCI controls. Adjusted concentrations of PlGF were associated with AD only in the presence of significant CeVD. Elevated PlGF was significantly associated with higher burden of WMH and with CMBs in AD patients. CONCLUSIONS: Serum PlGF has potential utility as a biomarker for the presence of CeVD, specifically WMH and CMBs, in AD. Further studies are needed to elucidate the underlying pathophysiological mechanisms linking PlGF to CeVD, as well as to further assess PlGF's clinical utility.

Trends in length of stay, functional outcomes, and discharge destination stratified by disease type for inpatient rehabilitation in Singapore community hospitals from 1996 to 2005.

OBJECTIVE: To determine the trends in length of stay (LOS), rehabilitation functional outcome, and discharge destination of patients admitted for inpatient rehabilitation from 1996 to 2005 and stratified by disease in Singapore. DESIGN: Retrospective national data were extracted from medical records of community-based inpatient rehabilitation admissions in Singapore from 1996 to 2005. SETTING: Four community hospitals. PARTICIPANTS: There were 12,506 first admissions for rehabilitation; 40.6% were for stroke, 30.4% for fracture, 2.9% for lower limb (LL) joint replacement, 2.3% for LL amputation, 1.9% for cancer, 1.8% for falls, 1.6% for pneumonia, and 18.5% for other illnesses. The overall mean age ± SD was 73.2±11.5 years. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: LOS, rehabilitation outcomes (rehabilitation effectiveness [R-effectiveness], rehabilitation efficiency [R-efficiency], relative functional efficiency [Relative-FE]), and discharge destination. RESULTS: The overall median LOS for all disease groups decreased by 16.2% (37 to 31d) from 1996 to 2005. The sharpest decline in LOS among the 8 disease groups was observed in the LL amputation group. The overall mean ± SD admission and discharge activities of daily living scores were 45.6±25.7 and 60.3±28.9, respectively; median R-effectiveness was 28.8%, median R-efficiency was 12.9/30d, and median Relative-FE was 27.7%/30d. From 1996 to 2005, mean R-effectiveness increased by 184% (14% to 40%), R-efficiency increased by 104% (9 to 19 units/30d), and Relative-FE increased by 145% (21% to 51%/30d). Among all inpatient admissions, most were discharged home (78.2%), 10.9% were discharged to an acute hospital, and 9.8% were discharged to nursing or sheltered homes, with no significant change during the 10-year period. CONCLUSIONS: Rehabilitation outcomes of patients admitted to Singapore's community hospitals have improved between 1996 and 2005 despite a decreasing LOS. Discharge destinations have largely remained unchanged over this period.

Serum Cathepsin D Is a Potential Biomarker for Alzheimer's Disease Dementia and Cognitive Decline.

BACKGROUND: The lysosomal protease cathepsin D (catD) has been reported to be upregulated in postmortem Alzheimer's disease (AD) cortex, where it colocalized with neurofibrillary tangles and correlated with levels of phosphorylated tau, suggesting pathophysiological links between catD and neurodegeneration. In contrast, studies of serum catD in AD have yielded conflicting results, and potential associations between baseline serum catD and functional outcomes of patients are at present unknown. OBJECTIVE: We aimed to examine the status of serum catD in a Singapore-based longitudinal study of dementia and investigate catD associations with functional and cognitive decline. METHODS: 35 subjects with no cognitive impairment, 40 patients with cognitive impairment no dementia and 34 with AD dementia underwent annual neuropsychological assessments (mean follow-up=4.3 years), as well as collection of baseline serum for catD measurements by ELISA. RESULTS: Higher serum catD at baseline was associated with AD clinical diagnosis (odds ratios [OR]: 10.0; 95% confidence interval [CI]: 1.02-97.95) as well as with cortical atrophy. Furthermore, higher catD was associated with global cognitive and functional decline (OR: 9.94; 95% CI: 1.02-97.34). CONCLUSION: The associations of serum catD with AD dementia as well as atrophy provide further support for the proposed links between catD and neurodegeneration, as well as for the assessment of serum catD as a prognostic biomarker predicting global cognitive and functional decline in larger studies.

Associations of Blood Cardiovascular Biomarkers With Brain Free Water and Its Relationship to Cognitive Decline: A Diffusion-MRI Study.

BACKGROUND AND OBJECTIVES: There is an increasing awareness of the "Heart-Brain Connection," whereby cardiovascular function is connected with cognition. Diffusion-MRI studies reported higher brain free water (FW) was associated with cerebrovascular disease (CeVD) and cognitive impairment. In this study, we investigated whether higher brain FW was related to blood cardiovascular biomarkers and whether FW mediated the associations between blood biomarkers and cognition. METHODS: Participants recruited from 2 Singapore memory clinics between 2010 and 2015 underwent collection of blood samples and neuroimaging at baseline and longitudinal neuropsychological assessments up to 5 years. We examined the associations of blood cardiovascular biomarkers (high-sensitivity cardiac troponin-T [hs-cTnT], N-terminal pro-hormone B-type natriuretic peptide [NT-proBNP], and growth/differentiation factor 15 [GDF-15]) with brain white matter (WM) and cortical gray matter (GM) FW derived from diffusion MRI using whole brain voxel-wise general linear regression. We then assessed the relationships among baseline blood biomarkers, brain FW, and cognitive decline using path models. RESULTS: A total of 308 older adults (76 with no cognitive impairment, 134 with cognitive impairment no dementia, and 98 with Alzheimer disease dementia and vascular dementia; mean [SD] age: 72.1 [8.3]) were included. We found that blood cardiovascular biomarkers were associated with higher FW in widespread WM regions and in specific GM networks including the default mode, executive control, and somatomotor networks at baseline (p < 0.01, family-wise error corrected). Baseline FW in widespread WM and network-specific GM fully mediated the associations of blood biomarkers with longitudinal cognitive decline over 5 years. Specifically, in GM, higher FW in the default mode network mediated the relationship with memory decline (hs-cTnT: ß = -0.115, SE = 0.034, p = 0.001; NT-proBNP: ß = -0.154, SE = 0.046, p = 0.001; GDF-15: ß = -0.073, SE = 0.027, p = 0.006); by contrast, higher FW in the executive control network was responsible for executive function decline (hs-cTnT: ß = -0.126, SE = 0.039, p = 0.001; NT-proBNP: ß = -0.110, SE = 0.038, p = 0.004; GDF-15: ß = -0.117, SE = 0.035, p = 0.001). Similar full mediation effects of brain FW were also identified for baseline cognition. DISCUSSION: Results suggested a role of brain FW in linking cardiovascular dysfunction to cognitive decline. These findings provide new evidence for brain-heart interactions, paving the way for prediction and monitoring of domain-specific cognitive trajectory.

Qualitative study exploring heterogeneity in caregiving experiences post-stroke in Singapore.

OBJECTIVE: Stroke, a common illness in older adults, accounts for up to 4% of direct medical costs in developed nations. Informal caregiving contributing a significant proportion of economic burden post-stroke warrants a deeper understanding of the caregiving context to sustain caregiving arrangement. While literature exists describing differences in motivation and preferences of caregivers, limited literature explores differences in caregiving experiences of different types of caregivers (ie, spouse, adult-child, sibling or others). Addressing this gap, our study aimed to explore the caregiving experience of stroke survivors and their family caregivers across different caregiver identities in an Asian setting. DESIGN: Qualitative descriptive study. SETTING: Community setting. PARTICIPANTS: We conducted semi-structured interviews with 26 stroke survivors and 35 caregivers purposively sampled from an outpatient rehabilitation setting, an outpatient clinic and a support organisation. Data were analysed using thematic analysis. OUTCOME MEASURES: Themes including caregiving experience of stroke survivors and their family caregivers across different caregiver identities. RESULTS: Following five themes were reported: caregiver reserve, coping strategies, caregiver burden, competing commitments and role of foreign domestic worker (FDW) in family caregiving. Spouse caregivers were less willing to ask for help, commonly adopted faith-based, and spacing or recharging types of coping, reported emotional strain and shared limited accounts of FDWs. Adult-child caregivers were more willing to ask for help, engaged in alternative care arrangements involving FDWs, commonly adopted action-focussed coping and reported multidimensional caregiver burden. CONCLUSION: Our findings illustrated the heterogeneity in factors affecting caregiving experience across spouse and adult-child caregivers. Practical implications include conducting a needs assessment for caregiver-stroke survivor dyads and providing tailored support, training and information to help caregivers cope better.

Alzheimer's Disease THErapy With NEuroaid (ATHENE): A Randomized Double-Blind Delayed-Start Trial.

OBJECTIVES: Preclinical and clinical studies indicate a role for MLC901 (NeuroAiD II) in Alzheimer's disease (AD). The primary aim was to investigate its safety as add-on therapy to standard treatment and the secondary aims its effect on cognition and slowing disease progression. DESIGN: Randomized double-blind placebo-controlled delayed-start study. SETTING AND PARTICIPANT: Patients with mild to moderate probable AD by NINCDS-ADRDA criteria, stable on acetylcholinesterase inhibitors or memantine (n = 125), were randomized to receive MLC901 (early starters) or placebo (delayed starters) for 6 months, followed by a further 6 months when all patients received MLC901, in a delayed-start design (clinical trial registration: ClinicalTrials.gov, NCT03038035). METHODS: The primary outcome measure was occurrence of serious adverse events (SAEs) at 6 months. Secondary outcomes included the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) and other assessment scales. RESULTS: There was no significant difference in the risk of SAEs between early and delayed starters at month (M) 6 (22.6% vs 27.0%, risk difference -4.4%, 90% CI -16.9% to 8.3%). Similarly, there was no significant difference in the risk of adverse events and the occurrence of stroke or vascular events between early and delayed starters throughout the 12-month study period. Early starters did not differ significantly on ADAS-Cog from delayed starters at M6 [mean difference (MD) -1.0, 95% CI -3.3 to 1.3] and M12 (MD -2.35, 95% CI -5.45 to 0.74) on intention-to-treat analysis. Other cognitive assessment scales did not show significant differences. CONCLUSIONS AND IMPLICATIONS: This study of 125 persons with dementia found no evidence of a significant increase in adverse events between MLC901 and placebo, thus providing support for further studies on both efficacy and safety. Analyses suggest the potential of MLC901 in slowing down AD progression, but this requires further confirmation in larger and longer studies using biomarkers for AD.