The prophylactic use of negative-pressure wound therapy after cardiac surgery: a meta-analysis

Surgical site infections (SSIs) pose a frequent complication in cardiac surgery patients and lead to increased patient discomfort and extended hospitalization. This meta-analysis aimed to evaluate the protective role of single-use negative-pressure wound therapy (sNPWT) devices on closed surgical wounds after cardiac surgery, and explored their potential preventive application across all cardiac surgery patients. A comprehensive literature search was conducted on ScienceDirect, focusing on studies related to "negative pressure wound therapy" or "PICO negative pressure wound therapy" combined with "cardiac surgery" or "sternotomy," published between 2000 and 2022. Inclusion criteria encompassed case-control studies comparing sNPWT with traditional dressings on closed cardiac surgical incisions in adult patients undergoing median sternotomy without immediate postoperative infective complications, with available details on SSIs. A retrospective analysis of cases treated with sNPWT in our centre was also performed. The meta-analysis revealed a protective role of sNPWT, indicating a 44% risk reduction in overall SSIs (odds ratio 0.56) and a 40% risk reduction in deep wound infections (odds ratio 0.60). Superficial wound infections, however, showed non-significant protective effects. A single-centre study aligned with the meta-analysis findings, confirming the efficacy of sNPWT and was included in the meta-analysis. In conclusion, the meta-analysis and the single-centre study collectively support the protective role of negative pressure wound therapy against overall and deep SSIs, suggesting its potential prophylactic use on all cardiac surgery populations.

THE ASSOCIATION BETWEEN MEDITERRANEAN DIET ADHERENCE AND ALLOSTATIC LOAD IN OLDER ADULTS

Allostatic load (AL) is a multisystemic index of biological wear and tear which is associated with poor health outcomes. In recent years, researchers have examined the association between dietary pattern intake and AL; however, no studies to date have examined the relationship between AL and consumption of a Mediterranean diet. Blood and urine samples were collected from 201 community-dwelling older adults who completed a Food Frequency Questionnaire (FFQ). A Mediterranean Diet Score (MDS) was calculated based on previous recommendations and a sex-based AL index was calculated using a count-based approach for 16 biomarkers associated with neuroendocrine, immune, cardiovascular, or metabolic function. It was hypothesized that a higher MDS would associate with lower AL, and that this association would be particularly robust for the immune and metabolic subcomponents of the AL index. In support of the study hypotheses, generalized linear models revealed a significant inverse relationship between MDS and AL (ß = -0.03, P = 0.037). Furthermore, higher MDS was significantly associated with lower immune (ß = -0.06, P = 0.38) and metabolic (ß = -0.05, P = 0.039) subsystem scores, but was not associated with cardiovascular or neuroendocrine subsystem scores. Exploratory analyses further showed that the association was more robust in male than female participants. The current findings are interpreted with caution given the study design and sample characteristics. However, these findings contribute to the literature supporting the Mediterranean diet as an important lifestyle behavior that may support healthy aging.

EARLY LIFE ADVERSITY, ALLOSTATIC LOAD, AND COGNITIVE FUNCTION AMONG MIDDLE-AGED AND OLDER ADULTS

Early life adversity (ELA) is consequential for poor cognitive health in mid to late life. ELA is associated with higher allostatic load (AL), a biological indicator of physiological dysregulation due to cumulative wear-and-tear from chronic stress. Higher AL is also associated with poorer cognitive function across the lifespan. To date, however, a paucity of research has investigated AL as a mechanism through which ELA impacts cognition. Using cross-sectional data from the Midlife in the United States (MIDUS) Study, the objective of this study was to investigate the mediating role of AL in the relationship between ELA and cognitive performance (global cognition, episodic memory, executive function) among middle-aged and older adults without cognitive impairment (n=1541, mean age=53±12, 53% female). ELA, including physical, emotional, and sexual experiences, was measured retrospectively using the Childhood Trauma Questionnaire. AL was composed of 20 biomarker proxies of neuroendocrine, metabolic, inflammatory, and cardiovascular systems, stratified by sex. Cognitive performance was evaluated using a battery of neuropsychological tests from the Brief Test of Adult Cognition by Telephone. Controlling for age, education, and ethnicity, AL significantly mediated the relationship between ELA and global cognition (ß=-0.01,95%CI[-0.02,-0.003]) and executive function (ß=-0.01,95%CI[-0.02,-0.003]) such that higher ELA was associated with higher AL, and higher AL was associated with poorer global cognition and executive function. No such effects were found for episodic memory. Consistent with the biopsychosocial lifespan model of cognitive aging, findings suggest that ELA may become biologically embedded over time to negatively impact cognitive function in later adulthood in a domain-specific manner.

Plasma Long Chain Fatty Acids and Cognitive Function in Older Adults: A Comparison of Statistical Analyses

Omega-3 fatty acids (FAs) have been suggested as modifiable protective factors for cognitive decline because of their neuroprotective properties. However, the evidence is still inconsistent regarding types of omega-3 FAs, and the probable interrelation with other circulating long chain FAs (LCFAs). This study aimed to evaluate associations between 14 plasma LCFAs and four cognitive domains using a principal component analysis (PCA) and to compare results with those obtained using standard methods. A group of 386 healthy older adults aged 77 ± 4 years (53% women), selected from the NutCog Study, a sub-study from the Québec cohort on Nutrition and Successful Aging (NuAge), underwent a cognitive evaluation and fasting blood sampling. Verbal and non-verbal episodic memory, executive functioning, and processing speed were evaluated using validated tests. LCFAs circulating concentrations were measured by high-performance liquid chromatography using published procedures. Linear regressions adjusted for age, sex, education, and BMI were used to evaluate cross-sectional associations between LCFAs, using PCA or a more standard grouping (omega-3, omega-6, monounsaturated, and saturated LCFAs), and cognitive performance. Higher scoring on the omega-3 PCA factor and higher concentrations of total omega-3 FAs were both associated with better episodic non-verbal memory and processing speed. Higher eicosapentaenoic acid (EPA omega-3) was also associated with these two cognitive domains and with episodic verbal memory. The associations with total omega-3 FAs taken separately were of smaller magnitude than those with PCA. These results suggest that omega-3 FAs should be considered in combination with other LCFAs when evaluating the association with cognitive function.

Cross-country differences in basal and stress-induced cortisol secretion in older adults

Objective

Several studies have emphasized the association between socioeconomic status (SES) and inadequate response of the biological stress system. However, other factors related to SES are rarely considered, such as cultural values, social norms, organization, language and communication skills, which raises the need to investigate cross-country differences in stress response. Although some studies have shown differences in cortisol levels between immigrants and natives, there is no cross-country evidence regarding cortisol levels in country-native elders. This is particularly important given the high prevalence of stress-related disorders across nations during aging. The current study examined basal diurnal and reactive cortisol levels in healthy older adults living in two different countries.

Methods

Salivary cortisol of 260 older adults from Canada and Brazil were nalyzed. Diurnal cortisol was measured in saliva samples collected at home throughout two working days at awakening, 30 min after waking, 1400 h, 1600 h and before bedtime. Cortisol reactivity was assessed in response to the Trier Social Stress Test (TSST) in both populations.

Results

Our results showed that even under similar health status, psychological and cognitive characteristics, Brazilian elders exhibited higher basal and stress-induced cortisol secretion compared to the Canadian participants.

Conclusion

These findings suggest that country context may modulate cortisol secretion and could impact the population health.

The effects of stress and stress hormones on human cognition: Implications for the field of brain and cognition

In this review, we report on studies that have assessed the effects of exogenous and endogenous increases in stress hormones on human cognitive performance. We first describe the history of the studies on the effects of using exogenous stress hormones such as glucocorticoids as anti-inflammatory medications on human cognition and mental health. Here, we summarize the cases that led to the diagnosis of glucocorticoid-induced 'steroid psychosis' in human populations and which demonstrated that these stress hormones could thus cross the blood-brain barrier and access the brain where they could influence cognition and mental health. We then summarize studies that assessed the effects of the exogenous administration of glucocorticoids on cognitive performance supported by the hippocampus, the frontal lobes and amygdala. In the second section of the paper, we summarize the effects of the endogenous release of glucocorticoids induced by exposure to a stressful situation on human cognition and we further dissociate the effects of emotion from those of stress on human learning and memory. Finally, in the last section of the paper, we discuss the potential impact that the environmental context to which we expose participants when assessing their memory could have on their reactivity to stress and subsequent cognitive performance. In order to make our point, we discuss the field of memory and aging and we suggest that some of the 'age-related memory impairments' observed in the literature could be partly due to increased stress reactivity in older adults to the environmental context of testing. We also discuss the inverse negative correlations reported between hippocampal volume and memory for young and older adults and suggest that these inverse correlations could be partly due to the effects of contextual stress in young and older adults, as a function of age-related differences in hippocampal volume.

The limits of 'adaptive' coping: well-being and mood reactions to stressors among women in abusive dating relationships

Coping is typically thought to be adaptive if it reduces immediate distress and promotes well-being. However, coping strategies might appear beneficial in a given situation, but when considered in the broader stressor context, those situational benefits may actually undermine well-being. Two studies (N = 473 and N = 80 women) demonstrated that, in the context of psychologically or physically abusive dating relationships, coping orientations were rooted in women's stressor history (prior assault trauma) and elevated emotion-focused and lower problem-focused efforts were predictive of greater depressive symptoms. Yet, in response to a stressor video that acted as a reminder of women's abusive experiences (but not to a stressor video unrelated to abuse), affective benefits (lower hostility, higher positive agency) were associated with abused women's emotion-focused coping endorsements, but were not linked to problem-focused coping. It seems that in some contexts, reduced distress might limit active efforts to alter a dysfunctional situation.

The Douglas Hospital Longitudinal Study of Normal and Pathological Aging: summary of findings

In 1988, our group initiated the Douglas Hospital Longitudinal Study of Normal and Pathological Aging to assess the association between secretion of the stress hormone cortisol and cognitive performance in a group of 51 older adults. In this paper, we summarize the data obtained in this study to date. We have found that long-term exposure to high endogenous levels of cortisol is associated with both memory impairments and a 14; smaller volume of the hippocampus. We also report on studies showing that in older adults with moderate levels of cortisol over time, memory performance can be acutely modulated by pharmacologic manipulations of cortisol. We describe one participant who was included in the group of older adults presenting with increased cortisol levels over time, memory impairments and reduced hippocampal volume and in whom major depression, followed by Alzheimer's disease, developed during the course of the study. Together, the results of the Douglas Hospital Longitudinal Study of Normal and Pathological Aging show that increased secretion of cortisol in the older human population is significantly associated with impairment of cognitive function during aging.

Stress hormones and human memory function across the lifespan

In this paper, we summarize the data obtained in our laboratory showing the effects of glucocorticoids on human cognitive function in older adults, young adults and children. We first present data obtained in the aged human population which showed that long-term exposure to high endogenous levels of glucocorticoids is associated with both memory impairments and a 14% smaller volume of the hippocampus. We then report on studies showing that in older adults with moderate levels of glucocorticoids, memory performance can be acutely modulated by pharmacological manipulations of glucocorticoids. In young adults, we present data obtained in our laboratory showing that cognitive processing sustained by the frontal lobes is also sensitive to acute increases of glucocorticoids. We also summarize studies showing that just as in older adults, memory performance in young adults can be acutely modulated by pharmacological manipulations of glucocorticoids. We then present a study in which we showed a differential involvement of adrenergic and glucocorticoid hormones for short- and long-term memory of neutral and emotional information. In the last section of the paper, we present data obtained in a population of young children and teenagers from low and high socioeconomic status (SES), where we showed that children from low SES present significantly higher levels of basal cortisol when compared to children from high SES. We then present new data obtained in this population showing that children and teenagers from low and high SES do not process the plausibility of positive and negative attributes in the same way. Children from low SES tended to process positive and negative attributes on a more negative note than children from high SES, and this type of processing was significantly related to basal cortisol at age 10, 12 and 14. Altogether, the results of these studies show that both bottom-up (effects of glucocorticoids on cognitive function), and top-down (effects of cognitive processing on glucocorticoid secretion) effects exist in the human population.

["Precursor phenomena" as a criterion in the choice of prevention of primary headache of the hemicrania type]

The importance of headache precursors as expression of latent headache is emphasized. The authors report data from a clinical-epidemiological survey of 322 youngster (143 m and 179 f) aged 4-16 with primary headache aimed at assessing latent time between precursors and onset of headache. The appearance of precursors is considered the time appropriate for prophylaxis.