To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Self-reported activity restriction is an established correlate of depression in dementia caregivers (dCGs). It is plausible that the daily distribution of objectively measured activity is also altered in dCGs with depression symptoms; if so, such activity characteristics could provide a passively measurable marker of depression or specific times to target preventive interventions. We therefore investigated how levels of activity throughout the day differed in dCGs with and without depression symptoms, then tested whether any such differences predicted changes in symptoms 6 months later.
Design, setting, participants, and measurements:
We examined 56 dCGs (mean age = 71, standard deviation (SD) = 6.7; 68% female) and used clustering to identify subgroups which had distinct depression symptom levels, leveraging baseline Center for Epidemiologic Studies of Depression Scale–Revised Edition and Patient Health Questionnaire-9 (PHQ-9) measures, as well as a PHQ-9 score from 6 months later. Using wrist activity (mean recording length = 12.9 days, minimum = 6 days), we calculated average hourly activity levels and then assessed when activity levels relate to depression symptoms and changes in symptoms 6 months later.
Clustering identified subgroups characterized by: (1) no/minimal symptoms (36%) and (2) depression symptoms (64%). After multiple comparison correction, the group of dCGs with depression symptoms was less active from 8 to 10 AM (Cohen’s d ≤ −0.9). These morning activity levels predicted the degree of symptom change on the PHQ-9 6 months later (per SD unit β = −0.8, 95% confidence interval: −1.6, −0.1, p = 0.03) independent of self-reported activity restriction and other key factors.
These novel findings suggest that morning activity may protect dCGs from depression symptoms. Future studies should test whether helping dCGs get active in the morning influences the other features of depression in this population (i.e. insomnia, intrusive thoughts, and perceived activity restriction).
The aim of this study was to perform a systematic review and meta-analysis of the diagnostic accuracy of a point-of-care ultrasound exam for undifferentiated shock in patients presenting to the emergency department.
Ovid MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, and research meeting abstracts were searched from 1966 to June 2018 for relevant studies. QUADAS-2 was used to assess study quality, and meta-analysis was conducted to pool performance data of individual categories of shock.
A total of 5,097 non-duplicated studies were identified, of which 58 underwent full-text review; 4 were included for analysis. Study quality by QUADAS-2 was considered overall a low risk of bias. Pooled positive likelihood ratio values ranged from 8.25 (95% CI 3.29 to 20.69) for hypovolemic shock to 40.54 (95% CI 12.06 to 136.28) for obstructive shock. Pooled negative likelihood ratio values ranged from 0.13 (95% CI 0.04 to 0.48) for obstructive shock to 0.32 (95% CI 0.16 to 0.62) for mixed-etiology shock.
The rapid ultrasound for shock and hypotension (RUSH) exam performs better when used to rule in causes of shock, rather than to definitively exclude specific etiologies. The negative likelihood ratios of the exam by subtype suggest that it most accurately rules out obstructive shock.
Deficits in frontal lobe perfusion have been demonstrated in late-life depression; however, studies to date have generally involved small numbers, used neuroimaging rather than bedside testing and have not controlled for important covariates.
We aimed to examine the association between depressive symptoms and frontal lobe perfusion during standing, in a large cohort of community-dwelling older people.
Participants aged ≥50 years underwent continuous measurement of orthostatic blood pressure by finometry, and frontal lobe perfusion by near-infrared spectroscopy. Depressive symptoms were assessed by the eight-item Centre for Epidemiological Studies Depression Scale. Real-time frontal lobe cerebral oxygenation was measured by the Portalite System, detecting changes in frontal lobe perfusion and reporting a tissue saturation index score.
Almost 8% (209 out of 2616) had clinically significant depressive symptoms. Multilevel models demonstrated a significantly lower tissue saturation index in participants with depressive symptoms at both 60 and 90 s post-stand, with coefficients of −0.43 (95% CI −0.63 to −0.22) and −0.37 (95% CI −0.57 to −0.16), respectively. Controlling for relevant covariates did not significantly attenuate these associations. After addition of systolic blood pressure this association was no longer significant, suggesting lower blood pressure may modify this relationship.
This study demonstrates that lower frontal lobe perfusion, related to lower values of baseline systolic blood pressure, is associated with clinically significant depressive symptoms in a cohort of community-dwelling older people. Given the recognised longitudinal association between lower blood pressure and depression in older people, this may represent a potential therapeutic target for prevention of incident depression.
Both extinct and extant hominin populations display morphological features consistent with Bergmann's and Allen's Rules. However, the functional implications of the morphologies described by these ecological laws are poorly understood. We examined this through the lens of endurance running. Previous research concerning endurance running has focused on locomotor energetic economy. We considered a less-studied dimension of functionality, thermoregulation. The performance of male ultra-marathon runners (n = 88) competing in hot and cold environments was analysed with reference to expected thermoregulatory energy costs and the optimal morphologies predicted by Bergmann's and Allen's Rules. Ecogeographical patterning supporting both principles was observed in thermally challenging environments. Finishers of hot-condition events had significantly longer legs than finishers of cold-condition events. Furthermore, hot-condition finishers had significantly longer legs than those failing to complete hot-condition events. A degree of niche-picking was evident; athletes may have tailored their event entry choices in accordance with their previous race experiences. We propose that the interaction between prolonged physical exertion and hot or cold climates may induce powerful selective pressures driving morphological adaptation. The resulting phenotypes reduce thermoregulatory energetic expenditure, allowing diversion of energy to other functional outcomes such as faster running.
According to Mahr & Csibra (M&C), the view that the constructive nature of episodic memory is related to its role in simulating future events has difficulty explaining why memory is often accurate. We hold this view, but disagree with their conclusion. Here we consider ideas and evidence regarding flexible recombination processes in episodic retrieval that accommodate both accuracy and distortion.
Stress-related pathophysiology drives comorbid trajectories that elude precise prediction. Allostatic load algorithms that quantify biological “wear and tear” represent a comprehensive approach to detect multisystemic disease processes of the mind and body. However, the multiple morbidities directly or indirectly related to stress physiology remain enigmatic. Our aim in this article is to propose that biological comorbidities represent discrete pathophysiological processes captured by measuring allostatic load. This has applications in research and clinical settings to predict physical and psychiatric comorbidities alike. The reader will be introduced to the concepts of allostasis, allostasic states, allostatic load, and allostatic overload as they relate to stress-related diseases and the proposed prediction of biological comorbidities that extend rather to understanding psychopathologies. In our transdisciplinary discussion, we will integrate perspectives related to (a) mitochondrial biology as a key player in the allostatic load time course toward diseases that “get under the skin and skull”; (b) epigenetics related to child maltreatment and biological embedding that shapes stress perception throughout lifespan development; and (c) evolutionary drivers of distinct personality profiles and biobehavioral patterns that are linked to dimensions of psychopathology.
The relative contribution of demographic, lifestyle and medication factors to the association between affective disorders and cardiometabolic diseases is poorly understood.
To assess the relationship between cardiometabolic disease and features of depresion and bipolar disorder within a large population sample.
Cross-sectional study of 145 991 UK Biobank participants: multivariate analyses of associations between features of depression or bipolar disorder and five cardiometabolic outcomes, adjusting for confounding factors.
There were significant associations between mood disorder features and ‘any cardiovascular disease’ (depression odds ratio (OR) = 1.15, 95% CI 1.12–1.19; bipolar OR = 1.28, 95% CI 1.14–1.43) and with hypertension (depression OR = 1.15, 95% CI 1.13–1.18; bipolar OR = 1.26, 95% CI 1.12–1.42). Individuals with features of mood disorder taking psychotropic medication were significantly more likely than controls not on psychotropics to report myocardial infarction (depression OR = 1.47, 95% CI 1.24–1.73; bipolar OR = 2.23, 95% CI 1.53–3.57) and stroke (depression OR = 2.46, 95% CI 2.10–2.80; bipolar OR = 2.31, 95% CI 1.39–3.85).
Associations between features of depression or bipolar disorder and cardiovascular disease outcomes were statistically independent of demographic, lifestyle and medication confounders. Psychotropic medication may also be a risk factor for cardiometabolic disease in individuals without a clear history of mood disorder.
Emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a non-native, wood-boring beetle that has caused widespread mortality of ash (Fraxinus Linnaeus (Oleaceae)) in eastern North America. During 2004–2007, we determined whether forest community composition and structure of black (F. nigra Marshall), green (F. pennsylvanica Marshall), and white (F. americana Linnaeus) ash stands influenced their susceptibility to EAB invasion in southeast Michigan, United States of America. There was no relationship between EAB-induced ash decline or percentage mortality and any measure of community composition (tree species diversity, stand/ash density, total basal area, or relative dominance of ash). There was also no relationship between measures of EAB impact (density of EAB signs, ash decline rating, percentage ash mortality, or percentage infested ash) and forest attributes (ash/total stand density, basal area, ash importance, or stand diversity). Decline and mortality of black ash advanced more rapidly than that of white and green ash. Percentage mortality of ash increased from 51% to 93% during 2004–2007. Distance from the epicentre of the invasion was negatively correlated with ash mortality, but this relationship dissipated over time. Stand composition data suggests that ash will be replaced by Quercus Linnaeus (Fagaceae), Acer Linnaeus (Sapindaceae), and Tilia Linnaeus (Malvaceae); such vegetation changes will irreversibly alter the structure and function of these forests.