Sex Differences in Cardiovascular Risk Factors for Dementia

Towards a Deeper Understanding: Utilizing Machine Learning to Investigate the Association between Obesity and Cognitive Decline-A Systematic Review

Background/Objectives: Several studies have shown a relation between obesity and cognitive decline, highlighting a significant global health challenge. In recent years, artificial intelligence (AI) and machine learning (ML) have been integrated into clinical practice for analyzing datasets to identify new risk factors, build predictive models, and develop personalized interventions, thereby providing useful information to healthcare professionals. This systematic review aims to evaluate the potential of AI and ML techniques in addressing the relationship between obesity, its associated health consequences, and cognitive decline. Methods: Systematic searches were performed in PubMed, Cochrane, Web of Science, Scopus, Embase, and PsycInfo databases, which yielded eight studies. After reading the full text of the selected studies and applying predefined inclusion criteria, eight studies were included based on pertinence and relevance to the topic. Results: The findings underscore the utility of AI and ML in assessing risk and predicting cognitive decline in obese patients. Furthermore, these new technology models identified key risk factors and predictive biomarkers, paving the way for tailored prevention strategies and treatment plans. Conclusions: The early detection, prevention, and personalized interventions facilitated by these technologies can significantly reduce costs and time. Future research should assess ethical considerations, data privacy, and equitable access for all.

The effectiveness of exercise interventions targeting sleep in older adults with cognitive impairment or Alzheimer's disease and related dementias (AD/ADRD): A systematic review and meta-analysis

Sleep loss is associated with reduced health and quality of life, and increased risk of Alzheimer's disease and related dementias. Up to 66% of persons with Alzheimer's disease and related dementias experience poor sleep, which can predict or accelerate the progression of cognitive decline. Exercise is a widely accessible intervention for poor sleep that can protect against functional and cognitive decline. No previous systematic reviews have investigated the effectiveness of exercise for sleep in older adults with mild cognitive impairment or Alzheimer's disease and related dementias. We systematically reviewed controlled interventional studies of exercise targeting subjectively or objectively (polysomnography/actigraphy) assessed sleep in persons with mild cognitive impairment or Alzheimer's disease and related dementias. We conducted searches in PubMed, Embase, Scopus and Cochrane-Library (n = 6745). Nineteen randomised and one non-randomised controlled interventional trials were included, representing the experiences of 3278 persons with mild cognitive impairment or Alzheimer's disease and related dementias. Ten had low-risk, nine moderate-risk, and one high-risk of bias. Six studies with subjective and eight with objective sleep outcomes were meta-analysed (random-effects model). We found moderate- to high-quality evidence for the beneficial effects of exercise on self-reported and objectively-measured sleep outcomes in persons with mild cognitive impairment or Alzheimer's disease and related dementias. However, no studies examined key potential moderators of these effects, such as sex, napping or medication use. Our results have important implications for clinical practice. Sleep may be one of the most important modifiable risk factors for a range of health conditions, including cognitive decline and the progression of Alzheimer's disease and related dementias. Given our findings, clinicians may consider adding exercise as an effective intervention or adjuvant strategy for improving sleep in older persons with mild cognitive impairment or Alzheimer's disease and related dementias.

How cy pres promotes transdisciplinary convergence science: an academic health center for women's cardiovascular and brain health

Cardiovascular disease (CVD) is largely preventable, and the leading cause of death for men and women. Though women have increased life expectancy compared to men, there are marked sex disparities in prevalence and risk of CVD-associated mortality and dementia. Yet, the basis for these and female-male differences is not completely understood. It is increasingly recognized that heart and brain health represent a lifetime of exposures to shared risk factors (including obesity, hyperlipidemia, diabetes, and hypertension) that compromise cerebrovascular health. We describe the process and resources for establishing a new research Center for Women's Cardiovascular and Brain Health at the University of California, Davis as a model for: (1) use of the cy pres principle for funding science to improve health; (2) transdisciplinary collaboration to leapfrog progress in a convergence science approach that acknowledges and addresses social determinants of health; and (3) training the next generation of diverse researchers. This may serve as a blueprint for future Centers in academic health institutions, as the cy pres mechanism for funding research is a unique mechanism to leverage residual legal settlement funds to catalyze the pace of scientific discovery, maximize innovation, and promote health equity in addressing society's most vexing health problems.

Investigating Sex Differences in Risk and Protective Factors in the Progression of Mild Cognitive Impairment to Dementia: A Systematic Review

BACKGROUND

Developing effective strategies for reducing dementia risk requires a detailed understanding of the risk and protective factors associated with the progression of mild cognitive impairment (MCI) to dementia.

OBJECTIVE

We aimed to systematically review the evidence for sex differences in these factors.

METHODS

Five online databases (PubMed/CINAHL/EMBASE/PsycINFO/Cochrane) were searched from inception until 17 October 2022 for cohort studies that focused on sex differences in risk and protective factors in the progression of MCI to dementia.

RESULTS

A total of 2,972 studies were identified, of which 12 studies from five countries were included in the systematic review. There was substantial variability in study designs, study populations and outcome measures. Sex differences were present in the associations of sociodemographic, health, psychological factors, genetic and other biomarkers with the progression of MCI to dementia. APOE ɛ4 status and depression appeared to increase the risk of progression for females, whereas history of stroke, MRI markers and cerebrospinal fluid biomarkers appeared to increase the risk of progression for males. APOE ɛ2 status and marital status (unmarried) were observed to reduce risk of progression in males and females, respectively.

CONCLUSIONS

The ability of studies to accurately detail risk factors for dementia are likely limited when solely controlling for the effects of sex. Although the heterogeneity and underpowered nature of the studies made it difficult to synthesize the findings for each risk factor, this study highlights the apparent need for further research examining risk factors for dementia in males and females with MCI separately.

Sex and gender differences in risk scores for dementia and Alzheimer's disease among cisgender, transgender, and non-binary adults

INTRODUCTION

Few studies have explored dementia risk according to sex and gender including for transgender and non-binary adults. This study evaluated dementia risk factors and risk scores among cisgender, transgender, and non-binary adults.

METHODS

Observational data were drawn from the 2019 Behavioral Risk Factor Surveillance System. A matched-cohort approach was used to develop sex (male, female) and gender identity cohorts (cisgender men, cisgender women, transgender men, transgender women, and non-binary adults) for comparison. Dementia risk scores were calculated using established mid-life and late-life risk score algorithms.

RESULTS

Males had higher overall mid-life dementia risk, and lower late-life Alzheimer's disease risk compared to females. Transgender men, transgender women, and non-binary adults had higher overall late-life risk compared to both cisgender men and women.

DISCUSSION

Future research is needed to build the evidence base for specific risk factors that may be contributing to higher overall risk among understudied and underserved gender groups.

HIGHLIGHTS

Using data from the 2019 Behavioral Risk Factor Surveillance System, this matched-cohort study found that those assigned female at birth had lower overall mid-life dementia risk and higher overall late-life Alzheimer's disease (AD) risk compared to those assigned male at birth. Transgender men, transgender women, and non-binary adults all showed higher overall late-life AD risk compared to cisgender men and cisgender women. Between-group differences were found in the incidence of specific risk and protective factors for dementia and AD.

Sex Hormone-Binding Globulin and Risk of Incident Dementia in Middle-Aged to Older Women: Results from the UK Biobank Cohort Study

INTRODUCTION

The association of serum sex hormone-binding globulin (SHBG) concentrations with dementia risk remains uncertain in middle-aged to older women. We examined associations of serum SHBG levels with incidence of all-cause dementia and its subtypes in middle-aged to older women from the large population-based UK Biobank cohort study.

METHODS

Serum total SHBG levels were measured by immunoassay. The incidence of all-cause dementia and its subtypes was recorded. Cox proportional hazards models were used to calculate hazard ratios (HR) for main outcomes.

RESULTS

Among 171,482 community-dwelling women (mean [SD] age was 59.9 [5.4] years, median follow-up of 11.8 years), 2,368 developed dementia, including 1,088 from Alzheimer's disease (AD), 451 from vascular dementia (VAD), and 1,609 from other dementia. After multivariable adjustments, higher serum SHBG levels were significantly associated with higher risks of all-cause dementia, AD, and other dementia (all p < 0.05). Compared to those in the lowest quartile of SHBG levels, participants in the highest quartile of SHBG levels had a higher risk of all-cause dementia (HR: 1.34; 95% confidence interval [CI]: 1.16-1.53), AD (HR: 1.32; 95% CI: 1.07-1.62), and other dementia (HR: 1.44; 95% CI: 1.21-1.70). However, this relationship was not significant for VAD (HR: 1.16; 95% CI: 0.86-1.56).

CONCLUSION

These findings indicated that higher serum SHBG concentrations were independently associated with higher risks of incident all-cause dementia, as well as AD and other dementia among middle-aged to older women. No association was found for VAD.

Sex-specific associations between diabetes and dementia: the role of age at onset of disease, insulin use and complications

BACKGROUND

Whether the association of type 2 diabetes (T2DM) with dementia was differed by sex remains unclear, and the roles of age at onset of disease, insulin use and diabetes' complications in their association are unknown.

METHODS

This study analyzed data of 447 931 participants from the UK Biobank. We used Cox proportional hazards models to estimate sex-specific hazard ratios (HRs) and 95% confidence intervals (CI), and women-to-men ratio of HRs (RHR) for the association between T2DM and incident dementia [all-cause dementia, Alzheimer's disease (AD), and vascular dementia (VD)]. The roles of age at onset of disease, insulin use and diabetes' complications in their association were also analyzed.

RESULTS

Compared to people with no diabetes at all, people with T2DM had increased risk of all-cause dementia (HR 2.85, 95% CI 2.56-3.17). The HRs between T2DM and AD were higher in women than men, with an RHR (95%CI) of 1.56 (1.20, 2.02). There was a trend that people who experienced T2DM before age 55 had higher risk of VD than those who had T2DM after age 55. In addition, there was a trend that T2DM had higher effect on VD that occurred before age 75 years than events that occurred after age 75. Patients with T2DM using insulin had higher risk of all-cause dementia than those without insulin, with an RHR (95%CI) of 1.54 (1.00-2.37). People with complications had doubled risk of all-cause dementia, AD and VD.

CONCLUSIONS

Adopting a sex-sensitive strategy to address the risk of dementia in patients with T2DM is instrumental for a precision medicine approach. Meanwhile, it is warranted to consider patients' age at onset of T2DM, insulin use status and complications conditions.

Sex Differences in Dementia

BackgroundWomen in many cohorts have a higher risk for Alzheimer's disease (AD), the most common form of dementia. Sex is a biological construct whereby differences in disease manifestation and prevalence are rooted in genetic differences between XX and XY combinations of chromosomes. This chapter focuses specifically on sex-driven differences in dementia, as opposed to differences driven by gender - a social construct referring to the societal norms that influence people's roles, relationships, and positional power throughout their lifetime.MethodsUsing a narrative review, this chapter explored the characteristics and risk factors for the dementias, alongside a discussion of sex differences including loss of sex steroid hormones in middle-aged women, differences in the prevalence of cardiovascular diseases and engagement in lifestyle protective factors for dementia.ResultsThe sex difference in AD prevalence may exist because of systematic and historic differences in risk and protective factors for dementia, including level of education obtained and socioeconomic status differences, which can impact on health and dementia risk.Levels of sex steroids decline significantly after menopause in women, whereas this is more gradual in men with age. Animal and cell culture studies show strong biological plausibility for sex steroids to protect the ageing brain against dementia. Sex steroid hormone replacement therapy has in some observational studies shown to protect against AD, but treatment studies in humans have mainly shown disappointing results. Cardiovascular disease (CVD) shares midlife medical risk (e.g. hypertension, hyperlipidaemia, obesity etc.) factors with AD and other forms of dementia, but also with related lifestyle risk - and protective factors (e.g. exercise, not smoking etc.). Men tend to die earlier of CVD, so fewer survive to develop AD at an older age. Those who do survive may have healthier lifestyles and fewer risk factors for both CVD and AD. An earlier age at menopause also confers great risk for both without hormone treatment.DiscussionIt could be the case that the decline in sex steroids around the menopause make women more susceptible to lifestyle-related risk factors associated with dementia and CVD, but this remains to be further investigated. Combining hormone treatment with lifestyle changes in midlife (e.g. exercise) could be an important preventative treatment for dementia and CVD in later life, but this also requires further research.

Sex/gender and socioeconomic differences in modifiable risk factors for dementia

Both sex/gender and socioeconomic differences have been reported in the prevalence of modifiable risk factors for dementia. However, it remains unclear whether the associations between modifiable risk factors for dementia and incident dementia differ by sex/gender or socioeconomic status. This study aimed to investigate sex/gender and socioeconomic differences in the associations of modifiable risk factors with incident dementia using a life-course perspective. We used data from the English Longitudinal Study of Ageing (2008/2009 to 2018/2019). A total of 8,941 individuals were included [mean (standard deviation) age, 66.1 ± 9.8 years; 4,935 (55.2%) were women]. No overall sex/gender difference in dementia risk was found. Dementia risk was higher among those who experienced childhood deprivation [hazard ratio (HR) = 1.51 (1.17; 1.96)], lower occupational attainment [HR low versus high = 1.60 (1.23; 2.09) and HR medium versus high = 1.53 (1.15; 2.06)], and low wealth [HR low versus high = 1.63 (1.26; 2.12)]. Though different associations were found among the subgroups, there might be a sex/gender difference in dementia risk only for low cognitive activity, suggesting a higher risk for women [HR = 2.61 (1.89; 3.60)] compared to men [HR = 1.73 (1.20; 2.49)]. No consistent socioeconomic differences in modifiable dementia risk were found. A population-based approach that tackles inequalities in dementia risk profiles directly may be more effective than individual approaches in dementia prevention.

Risk factors for dementia in the context of cardiovascular disease: A protocol of an overview of reviews

Background

Dementia is a major public health priority. Although there is abundant evidence of an association between dementia and poor cardiovascular health, findings have been inconsistent and uncertain in identifying which factors increase dementia risk in those with cardiovascular disease. Indeed, multiple variables including sociodemographic, economic, health, lifestyle and education may indicate who is at higher vs. lower dementia risk and could be used in prediction modelling. Therefore, the aim of this review is to synthesise evidence on the key risk factors for dementia in those with a history of cardiovascular disease.

Methods

This is an overview of reviews protocol, registered on PROSPERO (CRD42021265363). Four electronic databases including MEDLINE, EMBASE, PsycINFO, and the Cochrane Database of Systematic Reviews will be searched. Studies will be included if they are systematic reviews and/or meta-analyses that have investigated the risk of incident dementia (all-cause and subtypes including Alzheimer’s disease and vascular dementia) in people with a history of coronary heart disease, heart failure, atrial fibrillation, hypertension, hyperlipidaemia, and vascular stiffness. Study selection will be completed by two independent researchers according to the eligibility criteria, and conflicts resolved by a third reviewer. References will be exported into Covidence for title and abstract sifting, full-text review, and data extraction. Methodological quality will be assessed using the AMSTAR-2 criteria and confidence of evidence will be assessed using the GRADE classification. This overview of reviews will follow PRISMA guidelines. If there is sufficient homogeneity in the data, the results will be pooled, and a meta-analysis conducted to determine the strength of association between each risk factor and incident all-cause dementia and its subtypes for each cardiovascular diagnoses separately.

Discussion

We will create a comprehensive summary of the key risk factors linking cardiovascular diseases to risk of incident dementia. This knowledge is essential for informing risk predictive model development as well as the development of risk reduction and prevention strategies.

Age-dependent cognitive impairment, hydrocephalus and leukocyte infiltration in transgenic mice with endothelial expression of human EPHX2

Soluble epoxide hydrolase (sEH) is upregulated in microvascular endothelium of human brain with vascular cognitive impairment (VCI). Transgenic endothelial expression of human sEH in mice (Tie2hsEH) induces endothelial dysfunction (ED), a pathogenetic mechanism of VCI. We sought to determine if endothelial upregulation of sEH is sufficient to cause cognitive impairment, and if cognitive impairment due to chronic hypoperfusion induced by unilateral common carotid artery occlusion (CCAO) is exacerbated in Tie2hsEH mice. Behavioral performance was assessed by the open field, rotarod, novel object, Morris water maze and fear conditioning tests. Cerebral blood flow and brain morphology were evaluated by MRI, and inflammatory changes investigated using immunohistochemistry and flow cytometry. We demonstrate that transgenic endothelial expression of sEH is sufficient to induce cognitive impairment, associated with leukocyte infiltration, brain atrophy and accelerated, age-dependent ventriculomegaly, identifying ED and sEH upregulation as potential underlying mechanisms and therapeutic targets for VCI.

Traditional Chinese Medicine as a Promising Strategy for the Treatment of Alzheimer's Disease Complicated With Osteoporosis

Alzheimer’s disease (AD) and osteoporosis (OP) are progressive degenerative diseases caused by multiple factors, placing a huge burden on the world. Much evidence indicates that OP is a common complication in AD patients. In addition, there is also evidence to show that patients with OP have a higher risk of AD than those without OP. This suggests that the association between the two diseases may be due to a pathophysiological link rather than one disease causing the other. Several in vitro and in vivo studies have also proved their common pathogenesis. Based on the theory of traditional Chinese medicine, some classic and specific natural Chinese medicines are widely used to effectively treat AD and OP. Current evidence also shows that these treatments can ameliorate both brain damage and bone metabolism disorder and further alleviate AD complicated with OP. These valuable therapies might provide effective and safe alternatives to major pharmacological strategies.

Sex differences and modifiable dementia risk factors synergistically influence memory over the adult lifespan

Introduction

More women than men develop Alzheimer's disease, yet women perform better and show less decline on episodic memory measures, a contradiction that may be accounted for by modifiable risk factors for dementia.

Methods

Associations among age, sex, modifiable dementia risk factors, and cognition were measured in a cross‐sectional online sample (n = 21,840, ages 18 to 89).

Results

Across four tests of associative memory and executive functions, only a Face‐Name Association task revealed sex differences in associative memory that varied by age. Men had worse memory than women (the equivalent of performing similar to someone 4 years older) across ages. Men had larger age differences than women (ie, worse memory in older ages) among people with no to one risk factor, but not those with multiple risk factors.

Discussion

Because the relationship between dementia risk factors and age‐related memory differences varies between men and women, sex‐specific dementia prevention approaches are warranted.

The Role of Lipid Rafts and Membrane Androgen Receptors in Androgen’s Neurotoxic Effects

Sex differences have been observed in multiple oxidative stress–associated neurodegenerative diseases. Androgens, such as testosterone, can exacerbate oxidative stress through a membrane androgen receptor (mAR), AR45, localized to lipid rafts in the plasma membrane. The goal of this study is to determine if interfering with mAR localization to cholesterol-rich lipid rafts decreases androgen induced neurotoxicity under oxidative stress environments. We hypothesize that cholesterol-rich caveolar lipid rafts are necessary for androgens to induce oxidative stress generation in neurons via the mAR localized within the plasma membrane. Nystatin was used to sequester cholesterol and thus decrease cholesterol-rich caveolar lipid rafts in a neuronal cell line (N27 cells). Nystatin was applied prior to testosterone exposure in oxidatively stressed N27 cells. Cell viability, endocytosis, and protein analysis of oxidative stress, apoptosis, and mAR localization were conducted. Our results show that the loss of lipid rafts via cholesterol sequestering blocked androgen-induced oxidative stress in cells by decreasing the localization of mAR to caveolar lipid rafts.

Long-term ozone exposure and cognitive impairment among Chinese older adults: A cohort study

Ambient particulate matter pollution has been linked to impaired cognitive performance, but the effect of ambient ozone exposure on cognitive function remains largely unknown. We examined the association of long-term ozone exposure with the risk of cognitive impairment among a national representative cohort of 9,544 Chinese older adults (aged 65 years and over) with baseline normal cognition from the Chinese Longitudinal Healthy Longevity Survey (2005-2018). The ozone exposure of each participant was measured by annual mean ozone concentrations for the county of residence. Cognitive function was assessed by the Chinese version of the Mini-Mental State Examination (MMSE). We defined cognitive impairment as an MMSE score below 18 points accompanied by an MMSE score that declined ≥ 4 points from baseline. Cox proportional hazards models were applied to explore the association of ozone exposure with cognitive impairment. During the mean follow-up time of 6.5 years, 2,601 older adults developed cognitive impairment. Each 10-μg/m³ increase in annual mean ozone exposure was associated with a 10.4% increased risk of cognitive impairment. The exposure-response relationship between ozone exposure and risk of cognitive impairment showed a linear trend. Sensitivity analyses revealed the association to be robust. We found that older adults from Eastern, Central, and Southern China were particularly susceptible. Our results show that ozone is a risk factor for late-life cognitive decline. Reducing ambient ozone pollution may help delay the onset of cognitive impairment among older adults.

Vascular Dementia and Underlying Sex Differences

Vascular dementia (VaD) is the second most common form of dementia after Alzheimer's disease (AD); where Alzheimer's accounts for 60-70% of cases of dementia and VaD accounts for 20% of all dementia cases. VaD is defined as a reduced or lack of blood flow to the brain that causes dementia. VaD is also known occasionally as vascular contributions to cognitive impairment and dementia (VCID) or multi-infarct dementia (MID). VCID is the condition arising from stroke and other vascular brain injuries that cause significant changes to memory, thinking, and behavior, and VaD is the most severe stage while MID is produced by the synergistic effects caused by multiple mini strokes in the brain irrespective of specific location or volume. There are also subtle differences in the presentation of VaD in males and females, but they are often overlooked. Since 1672 when the first case of VaD was reported until now, sex and gender differences have had little to no research done when it comes to the umbrella term of dementia in general. This review summarizes the fundamentals of VaD followed by a focus on the differences between sex and gender when an individual is diagnosed. In addition, we provide critical evidence concerning sex and gender differences with a few of the main risk factors of VaD including pre-existing health conditions and family history, gene variants, aging, hormone fluctuations, and environmental risk factors. Additionally, the pharmaceutical treatments and possible mitigation of risk factors is explored.

The influence of social support on cognitive health in older women: a Women's Health Initiative study

Social support is associated prospectively with cognitive decline and dementia among the elderly; however, little is known about the impact of social support on healthy neurological aging. The current study investigates whether perceived social support has an influence on neurological health among a large sample of healthy postmenopausal women. Social support and neuropsychological outcomes were measured annually for six years through the Women's Health Initiative Study of Cognitive Aging. In postmenopausal women, higher perceived social support was associated with significantly better overall neuropsychological functioning at baseline, especially in the domains of short-delay figural memory, short-delay verbal memory, and semantic fluency. No significant associations were found between social support and longitudinal changes in neuropsychological function over a median follow-up period of six years. Additionally, there was no significant relationship between social support and regional brain volumes. These findings suggest that social support is related to performance in a subset of neuropsychological domains and contributes to the existing literature that points to the importance of social support as a modifiable lifestyle factor that has the potential to help protect against the decline of cognitive aging, specifically among older adult women.

Sex differences in dementia and response to a lifestyle intervention: Evidence from Nordic population-based studies and a prevention trial

INTRODUCTION

Evidence on sex differences in the risk for dementia has been mixed. The goal was to assess sex differences in the development of dementia, and in the effects of a lifestyle intervention.

METHODS

Two strategies were adopted, one using combined data from three large Nordic population-based cohort studies (n = 2289), adopting dementia as outcome, and 2-year multidomain lifestyle intervention (n = 1260), adopting cognitive change as outcome.

RESULTS

There was higher risk for dementia after age 80 years in women. The positive effects of the lifestyle intervention on cognition did not significantly differ between men and women. Sex-specific analyses suggested that different vascular, lifestyle, and psychosocial risk factors are important for women and men in mid- and late-life.

CONCLUSION

Women had higher risk for dementia among the oldest individuals. Lifestyle interventions may be effectively implemented among older men and women.

Decomposition of gender differences in cognitive functioning: National Survey of the Japanese elderly

Background

It is well known that females generally live longer than males, but women tend to suffer from more illnesses and limitations than men do, also for dementia. However, limited empirical evidence is available why this ‘male-female health-survival paradox’ is observed. This study aimed to investigate factors which account for gender differences in health, particularly cognitive functioning and decline among older adults.

Methods

Data were retrieved from the National Survey of the Japanese Elderly, which is a longitudinal survey of a nationwide representative sample of Japanese adults aged 60 or over. Gender differences in cognitive functioning and decline in three-year follow-ups were decomposed using Blinder–Oaxaca decomposition analysis, regarding demographic, socioeconomic, and health-related factors into the ‘explained’ component, by differences in individual attributes listed above, and the ‘unexplained’ component.

Results

Empirical analyses showed that women’s lower cognitive functioning was partly explained by the endowment effect. Moreover, a shorter duration of formal education and a larger proportion with their longest occupation being domestic worker accounted for steeper cognitive decline and more prevalent mild cognitive impairment in women than in men.

Conclusion

This empirical study suggested that gender differences in cognitive functioning and decline account for different individual attributes of social determinants among men and women. Particularly, men seem to be more engaged in activities which accumulate intellectual experiences through education and occupation, as suggested by the cognitive reserve hypothesis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-020-01990-1.

Effect of Caffeine Consumption on the Risk for Neurological and Psychiatric Disorders: Sex Differences in Human

Caffeine occurs naturally in various foods, such as coffee, tea, and cocoa, and it has been used safely as a mild stimulant for a long time. However, excessive caffeine consumption (1~1.5 g/day) can cause caffeine poisoning (caffeinism), which includes symptoms such as anxiety, agitation, insomnia, and gastrointestinal disorders. Recently, there has been increasing interest in the effect of caffeine consumption as a protective factor or risk factor for neurological and psychiatric disorders. Currently, the importance of personalized medicine is being emphasized, and research on sex/gender differences needs to be conducted. Our review focuses on the effect of caffeine consumption on several neurological and psychiatric disorders with respect to sex differences to provide a better understanding of caffeine use as a risk or protective factor for those disorders. The findings may help establish new strategies for developing sex-specific caffeine therapies.

Diagnostic accuracy of the CAM-ICU and ICDSC in detecting intensive care unit delirium: A bivariate meta-analysis

BACKGROUND

Delirium is a critical and highly prevalent problem among critically ill patients. The Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) and the Intensive Care Delirium Screening Checklist (ICDSC) are the most recommended assessment tools for detecting intensive care unit (ICU) delirium.

OBJECTIVES

To synthesize the current evidence and compared the diagnostic accuracy of the two tools in the detection of delirium in adults in ICUs.

DESIGN

Systematic review and meta-analysis.

DATA SOURCE

A comprehensive search of the following electronic databases was performed using PubMed, Embase, CINAHL and ProQuest Dissertations and Theses A&I. The date range searched was from database inception to April 26, 2019.

REVIEW METHODS

Two researchers independently identified articles, systematically abstracted data and evaluated the sensitivity and specificity of the CAM-ICU or the ICDSC against standard references. Bivariate diagnostic statistical analysis with a random-effects model was performed to summarize the pooled sensitivity and specificity of the two tools.

RESULTS

In total, 29 CAM-ICU and 12 ICDSC studies were identified. The pooled sensitivity was 0.84 and 0.83 and pooled specificity was 0.95 and 0.87 for the CAM-ICU and the ICDSC, respectively. The CAM-ICU had higher summary specificity than the ICDSC did (p = 0.04). The percentage of hypoactive delirium, ICU type, use of mechanical ventilation, number of participants, and female percentage moderated the accuracy of the tools. Most of the domains of patient selection, index test, reference standards, and flow and timing were rated as having a low or unclear risk of bias.

CONCLUSIONS

Although both the CAM-ICU and the ICDSC are accurate assessment tools for screening delirium in critically ill patients, the CAM-ICU is superior in ruling out patients without ICU delirium and detecting delirium in patients in the medical ICU and those receiving mechanical ventilation. Further investigations are warranted to validate our findings. The study protocol is registered at PROSPERO (CRD42020133544).

Alzheimer's Disease and Cardiovascular Disease: A Particular Association

Methods

This review is based on the material obtained via MEDLINE (PubMed), EMBASE, and Clinical Trials databases, from January 1980 until May 2019. The search term used was "Alzheimer's disease," combined with "cardiovascular disease," "hypertension," "dyslipidaemia," "diabetes mellitus," "atrial fibrillation," "coronary artery disease," "heart valve disease," and "heart failure." Out of the 1,328 papers initially retrieved, 431 duplicates and 216 records in languages other than English were removed. Among the 681 remaining studies, 98 were included in our research material on the basis of the following inclusion criteria: (a) the community-based studies; (b) using standardized diagnostic criteria; (c) reporting raw prevalence data; (d) with separate reported data for sex and age classes.

Results

While AD and CVD alone may be considered deleterious to health, the study of their combination constitutes a clinical challenge. Further research will help to clarify the real impact of vascular factors on these diseases. It may be hypothesized that there are various mechanisms underlying the association between AD and CVD, the main ones being hypoperfusion and emboli, atherosclerosis, and the fact that, in both the heart and brain of AD patients, amyloid deposits may be present, thus causing damage to these organs.

Conclusions

AD and CVD are frequently associated. Further studies are needed in order to understand the effect of CVD and its risk factors on AD in order to better comprehend the effects of subclinical and clinical CVD on the brain. Finally, we need to clarify the impact of the underlying hypothesized mechanisms of this association and to investigate gender issues.

Sex differences in Alzheimer's disease: Understanding the molecular impact

Alzheimer's disease (AD) is a common neurodegenerative disorder that presents with cognitive impairment and behavioral disturbance. Approximately 5.5 million people in the United States live with AD, most of whom are over the age of 65 with two-thirds being woman. There have been major advancements over the last decade or so in the understanding of AD neuropathological changes and genetic involvement. However, studies of sex impact in AD have not been adequately integrated into the investigation of disease development and progression. It becomes indispensable to acknowledge in both basic science and clinical research studies the importance of understanding sex-specific differences in AD pathophysiology and pathogenesis, which could guide future effort in the discovery of novel targets for AD. Here, we review the latest and most relevant literature on this topic, highlighting the importance of understanding sex dimorphism from a molecular perspective and its association to clinical trial design and development in AD research field.

A Guide to Applying the Sex-Gender Perspective to Nutritional Genomics

Precision nutrition aims to make dietary recommendations of a more personalized nature possible, to optimize the prevention or delay of a disease and to improve health. Therefore, the characteristics (including sex) of an individual have to be taken into account as well as a series of omics markers. The results of nutritional genomics studies are crucial to generate the evidence needed so that precision nutrition can be applied. Although sex is one of the fundamental variables for making recommendations, at present, the nutritional genomics studies undertaken have not analyzed, systematically and with a gender perspective, the heterogeneity/homogeneity in gene-diet interactions on the different phenotypes studied, thus there is little information available on this issue and needs to be improved. Here we argue for the need to incorporate the gender perspective in nutritional genomics studies, present the general context, analyze the differences between sex and gender, as well as the limitations to measuring them and to detecting specific sex-gene or sex-phenotype associations, both at the specific gene level or in genome-wide-association studies. We analyzed the main sex-specific gene-diet interactions published to date and their main limitations and present guidelines with recommendations to be followed when undertaking new nutritional genomics studies incorporating the gender perspective.