Understanding the relationship between cognition and death: a within cohort examination of cognitive measures and mortality

Risk Factors for Natural Cause Mortality in Schizophrenia

Importance

Schizophrenia is associated with premature mortality from mostly natural causes. Decreased cognitive functioning has been identified as a determinant of mortality in the general population. However, there have been few prospective studies of this issue in persons with schizophrenia.

Objective

To examine whether lower cognitive functioning is a risk factor for natural cause mortality in schizophrenia.

Design, Setting, and Participants

This prospective cohort study included persons with schizophrenia or schizoaffective disorder enrolled between February 1, 1999, and December 31, 2022, at a nonprofit psychiatric system in Baltimore, Maryland. Participants were evaluated using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and other clinical measures.

Exposure

Natural cause mortality.

Main Outcomes and Measures

Associations of cognitive function, obesity, tobacco smoking, and medical conditions with natural cause mortality were evaluated using Cox proportional hazards regression models.

Results

Of the 844 participants enrolled (mean [SD] age, 39.6 [12.1] years; 533 male [63.2%]), 158 (18.7%) died of natural causes during a median follow-up of 14.4 years (range, 7.0 days to 23.9 years). The most significant factor associated with mortality was lower cognitive functioning as measured by the RBANS (Cox coefficient, -0.04; 95% CI, -0.05 to -0.03; z = -5.72; adjusted P < .001). Additional factors independently associated with mortality included the diagnosis of an autoimmune disorder (hazard ratio [HR], 2.86; 95% CI, 1.83-4.47; z = 4.62; adjusted P < .001), tobacco smoking (HR, 2.26; 95% CI, 1.55-3.30; z = 4.23; adjusted P < .001), diagnosis of chronic obstructive pulmonary disease (HR, 3.31; 95% CI, 1.69-6.49; z = 3.48; adjusted P = .006), body mass index as a continuous variable (HR, 1.06; 95% CI, 1.02-1.09; z = 3.30; adjusted P = .01), diagnosis of a cardiac rhythm disorder (HR, 2.56; 95% CI, 1.40-4.69; z = 3.06; adjusted P = .02), and being divorced or separated (HR, 1.80; 95% CI, 1.22-2.65; z = 2.97; adjusted P = .02). An RBANS score below the 50th percentile displayed a joint association with being a smoker, having an elevated body mass index, and having a diagnosis of an autoimmune or a cardiac rhythm disorder.

Conclusions and Relevance

In this prospective cohort study, lower cognitive functioning was a risk factor for natural cause mortality in schizophrenia. Efforts should be directed at methods to improve cognitive functioning, particularly among individuals with additional risk factors.

Association Between Cognitive Function and Risk of Chronic Kidney Disease: A Longitudinal Cohort and Mendelian Randomization Study

OBJECTIVE

To investigate the causal dose-response association between cognitive function and the risk of chronic kidney disease (CKD) by a longitudinal cohort and mendelian randomization study.

METHODS

The longitudinal cohort study included 396,600 participants without prior dementia and CKD from the UK Biobank. Cognitive function (including prospective memory, numeric memory, visuospatial memory, reaction time, and reasoning ability) was assessed by computerized touchscreen tests. Global cognitive function was defined as a composite score of those specific cognitive domains. A 2-stage mendelian randomization analysis was conducted with 12,979 cases of CKD and 379,424 controls. Genetically predicted global cognitive function was instrumented with 91 confirmed genome-wide significant variants. The study outcome was new-onset CKD. The study was conducted from March 13, 2006, to September 30, 2021.

RESULTS

During a median follow-up of 12.5 years, new-onset CKD developed in 13,090 participants. Per 1 SD score increments in reaction time (adjusted hazard ratio [HR], 0.97; 95% CI, 0.95 to 0.99), reasoning ability (adjusted HR, 0.91; 95% CI, 0.88 to 0.94), and global cognitive function (adjusted HR, 0.96; 95% CI, 0.95 to 0.98) were associated with a significantly lower risk of new-onset CKD. Compared with an incorrect answer in the prospective memory test, a correct answer was associated with a lower risk of new-onset CKD (adjusted HR, 0.82; 95% CI, 0.76 to 0.88). Mendelian randomization analyses found that per 1 SD score increments in genetically predicted global cognitive function resulted in a significantly (7%; 95% CI, 2% to 12%) lower risk of new-onset CKD.

CONCLUSION

A better cognitive function is causally associated with a lower risk of CKD in participants without prior dementia.

The association of cognitive function and its changes with all-cause mortality among community-dwelling older adults

Background

The association of cognitive function, its changes, and all-cause mortality has not reached a consensus, and the independence of the association between changes in cognitive function and mortality remains unclear. The purpose of this study was to evaluate the longitudinal association between baseline cognitive function and cognitive changes over 1 year with subsequent all-cause mortality among the older adults aged 60 and above.

Methods

A prospective cohort study utilizing the Community Older Adults Health Survey data. Initiated in 2018, the study annually assessed all individuals aged 60+ in Dalang Town, Dongguan City. Cognitive function was assessed using the Chinese version of the Mini-Mental State Examination (MMSE). A total of 6,042 older adults individuals were included, and multivariate Cox proportional hazard models were used to examine cognitive function's impact on mortality.

Results

Participants' median age was 70 years, with 39% men. Over a median 3.08-year follow-up, 525 died. Mortality risk increased by 6% per MMSE score decrease (adjusted HR = 1.06, 95%CI: 1.05-1.08). Compared to those with normal cognitive function at baseline, participants with mild cognitive impairment and moderate to severe cognitive impairment had significantly higher mortality risks (adjusted HR = 1.40, 95%CI: 1.07-1.82; HR = 2.49, 95%CI: 1.91-3.24, respectively). The risk of death was 5% higher for each one-point per year decrease in cognitive function change rate (HR = 1.05, 95%CI: 1.02-1.08). Compared with participants with stable cognitive function, those with rapid cognitive decline had a 79% increased risk of death (adjusted HR = 1.79, 95% CI: 1.11-2.87), with baseline cognitive function influencing this relationship significantly (P for interaction = 0.002).

Conclusion

Baseline cognitive impairment and rapid cognitive decline are associated with higher all-cause mortality risks in Chinese older adults. Baseline function influences the mortality impact of cognitive changes.

The effect of measurement error on the positive predictive value of PSW methods for SLD identification: How buffer zones dispel the illusion of inaccuracy

Patterns of Strengths and Weaknesses (PSW) methods are widely used for identifying specific learning disabilities (SLDs). Several researchers, however, have reported that the diagnostic accuracy of PSW methods is unacceptably low when strict thresholds were used to identify students with SLDs. We believe these findings give a misleading impression of the magnitude of the diagnostic errors that are likely to arise in PSW assessments. In a simulation study of 10 million cases using a simplified PSW method for demonstration, most of what have been called diagnostic errors were cases in which observed scores and true scores fell on opposite sides of a strict threshold but were still within a buffer zone the size of a typical measurement error. Because small score differences do not result in meaningfully different case conceptualizations, the use of buffer zones reveals that previous estimates of the diagnostic accuracy of PSW methods are misleadingly low. We also demonstrate that diagnostic decisions become increasingly reliable when observed scores are comfortably distant from diagnostic thresholds. For practitioners, we present a flowchart and practical guidelines to improve the accuracy and stability of SLD identification decisions.

Visual processing speed and its association with future dementia development in a population-based prospective cohort: EPIC-Norfolk

Visual processing deficits have frequently been reported when studied in individuals with dementia, which suggests their potential utility in supporting dementia screening. The study uses EPIC-Norfolk Prospective Population Cohort Study data (n = 8623) to investigate the role of visual processing speed assessed by the Visual Sensitivity Test (VST) in identifying the risk of future dementia using Cox regression analyses. Individuals with lower scores on the simple and complex VST had a higher probability of a future dementia diagnosis HR1.39 (95% CI 1.12, 1.67, P < 0.01) and HR 1.56 (95% CI 1.27, 1.90, P < 0.01), respectively. Although other more commonly used cognitive dementia screening tests were better predictors of future dementia risk (HR 3.45 for HVLT and HR 2.66, for SF-EMSE), the complex VST showed greater sensitivity to variables frequently associated with dementia risk. Reduced complex visual processing speed is significantly associated with a high likelihood of a future dementia diagnosis and risk/protective factors in this cohort. Combining visual processing tests with other neuropsychological tests could improve the identification of future dementia risk.

Cognitive performance and all-cause mortality in community dwellers of Amerindian ancestry living in rural Ecuador: A population-based, longitudinal prospective study

OBJECTIVE

There is limited information on mortality risk in individuals with cognitive impairment living in rural Latin America. In this study, we assess the association between cognitive impairment and all-cause mortality in adults of Amerindian ancestry living in rural Ecuador.

PATIENTS AND METHODS

Middle-aged and older adults enrolled in the population-based Three Villages Study cohort were followed prospectively in order to estimate mortality risk according to their baseline cognitive performance as determined by the Montreal Cognitive Assessment (MoCA). Results were adjusted for demographics, level of education, traditional cardiovascular risk factors, symptoms of depression, severe tooth loss, and oily fish intake (factors previously associated with mortality in the study population).

RESULTS

Analysis included 1022 individuals followed for an average of 7.8 ± 3.4 years. Mean MoCA score was 21.2 ± 5.4 points (median: 22 points), with 334 (32.7%) individuals showing cognitive impairment, as evidenced by a MoCA score ≤ 19 points (the cutoff for poor cognitive performance based on previous studies in the same population). A total of 150 (14.7%) individuals died during the follow-up. Crude mortality rate was 2.87 per 100 person-years (95% C.I.: 2.08 - 3.96). For individuals with normal cognition, the mortality rate was 1.21 (95% C.I.: 0.92 - 1.50) while for those with cognitive impairment the rate increased to 3.48 (95% C.I.: 2.73 - 4.23). A multivariate Cox-proportional hazards model, confirmed that individuals with cognitive impairment had a significantly higher mortality risk than those without cognitive impairment (HR: 1.52; 95% C.I.: 1.05 - 2.18).

CONCLUSIONS

Cognitive impairment is associated with mortality in the study population.

Assessment of risk factors associated with long-term mortality in nursing homes: result from the SENIOR cohort

BACKGROUND

Previous studies on risk factors for death in nursing homes have focused on short-term observation and limited number risk factors.

AIMS

This study aims to identify factors predictive of 8-year survival in nursing homes.

METHODS

The study used the baseline measurements from the SENIOR cohort collected in 2013-2014. Data included clinical assessments (i.e., body composition, nutritional status, physical performance, level of dependence and cognition, frailty phenotype) as well as demographic information, number of medications and medical history. Mortality data were collected annually for 8 years. Univariate analyses were initially performed to assess potential predictive factors, followed by a Cox regression model using stepwise selection.

RESULTS

Of the 662 participants enrolled in the cohort, 58 (8.8%) were not further assessed due to the withdrawal of 2 nursing homes and 71 (10.7%) had no mortality data available (i.e., relocation, refusal to continue the study). Among the 533 patients included, 111 (20.8%) were still alive in 2022. Median survival time was 4 years (1.93-6.94). Multivariate regression showed that younger age (HR = 1.04 (1.03-1.06)), higher body mass index (HR = 0.96 (0.94-0.98)), higher score on the Mini-Mental State-Examination (HR = 0.97 (0.94-0.99)) and higher score on the Short Physical Performance Battery (HR = 0.93 (0.90-0.97)) were protective factors against mortality.

CONCLUSIONS

This study highlights that certain modifiable factors related to physical or mental health contribute to increased survival in nursing homes. Because of its ability to improve physical performance and partly cognitive function, promoting physical activity in nursing homes appears to be a public health priority.

The Relationship Between Cognition and Mortality Among Older Black and White Men in Advanced Cognitive Training for Independent and Vital Elderly

Objective: To determine the association between baseline cognition and all-cause mortality among Black men and White men. Methods: Data were from 614 Black and White men aged ≥65 years at baseline in the Advanced Cognitive Training for Independent and Vital Elderly trial and their linked mortality information. Cox proportional hazards models were used to determine the association between baseline cognition (memory, reasoning, speed of processing, Mini Mental State Exam) and mortality risk over 20 years, adjusting for covariates. Results: Among White men, higher performance on the memory composite measure was associated with a decreased risk of all-cause mortality (HR: 0.93; 95% CI: 0.89-0.98), whereas the other cognitive measures were not associated with all-cause mortality risk. Among Black men, none of the cognitive measures was associated with all-cause mortality risk. Discussion: There is a need for future work to recruit and retain a larger sample of older Black men to better understand the cognition-mortality relationship.

Association between all-cause mortality and trajectories across quality and duration of sleep and cognitive function: based on Group-Based Multivariate Trajectory modeling

BACKGROUND

Sleep duration and quality are associated with cognition, but the interaction of the 3 indicators and their association with all-cause mortality is unclear.

METHODS

We used data from the Chinese Longitudinal Healthy Longevity Survey from 2005-2018 to identify latent trajectories of sleep duration, sleep quality, and cognitive function. Secondly, the multinomial logistic model was adopted to determine predictors of trajectory groups. Finally, the Cox regression model was used to examine the association between these trajectory groups and all-cause mortality.

RESULTS

A total of 5046 adults (49% women) with an average age of 76.34 were included in the study. The median follow-up period was 11.11 years, during which 1784 (35%) participants died. We identified 4 latent groups among older adults: 'Good-performance' (51%), 'Decreasing' (26%), 'Oversleep & cognitive impairment' (12%), and 'Sleep-deprived' (11%). Individuals in the 'Decreasing' had a 51% increased risk of all-cause mortality (HR = 1.51, 95% CI: 1.25 - 1.81, p < .001). Individuals in the 'Oversleep & cognitive impairment' had a 170% increased risk of all-cause mortality (HR = 2.7 95% CI: 2.13 - 3.43, p < .001). Women had a higher risk of all-cause mortality regardless of trajectory group (47-143% men VS. 74-365% women). Both urban and rural areas have a similarly increased risk of all-cause mortality (48-179%).

CONCLUSIONS

Our study reveals the latent trajectories across sleep duration, sleep quality, and cognitive function in older Chinese and further explores their association with death. These findings provide a rational basis for cognitive interventions and reduce all-cause mortality.

Associations Between Cognitive Functioning and Mortality in a Population-Based Sample of Older United States Adults: Differences by Sex and Education

Objective: To determine whether cognition is associated with mortality among older US adults. Methods: We studied 5,989 National Health and Nutrition Examination Survey participants age 60+ in years 1999-2014 with mortality follow-up through 2015. Cognitive function was measured in one standard deviation decrements using the Digit Symbol Substitution Test (DSST), Animal Fluency (AnFl), and two Consortium to Establish a Registry for Alzheimer's Disease (CERAD) tests. Results: Each decrement in cognitive function was associated with increased risk of mortality overall (DSST HR: 1.36, 95% CI: 1.25, 1.48), among women only (AnFl: 1.51, 95% CI: 1.02, 2.24), and among those with less than a high school education only (AnFl HR: 1.46, 95% CI: 1.09, 1.97; CERAD-WL HR: 1.34, 95% CI: 1.07, 1.67; and CERAD-DR HR: 1.38, 95% CI: 1.05, 1.82). Discussion: Among US adults, lower cognitive functioning was associated with mortality; associations were stronger among women and those with less education.

The association between cognitive impairment and 30-day mortality among older Chinese inpatients

Purpose

Although the association between cognitive impairment and mortality has been widely described among community-dwelling older adults, this association in hospitalized patients was limited.

Objectives

This study's purpose was to explore the association between cognitive impairment and 30-day mortality after adjustment of factors among Chinese in-patients.

Methods

This was a large-scale prospective study based on a cohort of patients aged 65 years and older, whose cognitive function was assessed using the Mini-Cog instrument, followed up at 30-days for mortality. Multivariate logistic regression models were used to assess the association between cognitive impairment and 30-day mortality.

Results

There were 9,194 inpatients in our study, with an average age of 72.41 ± 5.72. The prevalence of cognitive impairment using the Mini-Cog instrument was 20.5%. Multivariable analyses showed that patients with cognitive impairment have an increased risk of 30-day mortality, compared to those with normal cognitive function (OR = 2.83,95%CI:1.89–4.24) in an unadjusted model. In the fully adjusted model, Patients with cognitive impairment had an increased risk of 30-day mortality compared to those with normal cognitive function in the completely adjusted model (OR = 1.76,95% CI: 1.14–2.73). Additionally, this association still existed and was robust after performing a stratified analysis of age, gender, frailty and depression, with no significant interaction (P > 0.05).

Conclusions

Our study found that older Chinese in-patients with cognitive impairment have a 1.76-fold risk of 30-day mortality compared to patients with normal cognitive function, suggesting that clinicians and nurses need to early implement cognitive function screening and corresponding interventions to improve clinical outcomes for older in-patients.

Novel Indices of Cognitive Impairment and Incident Cardiovascular Outcomes in the REWIND Trial

CONTEXT

Low cognitive scores are risk factors for cardiovascular outcomes. Whether this relationship is stronger using novel cognitive indices is unknown.

METHODS

Participants in the Researching Cardiovascular Events with a Weekly Incretin in Diabetes (REWIND) trial who completed both the Montreal Cognitive Assessment (MoCA) score and Digit Substitution Test (DSST) at baseline (N = 8772) were included. These scores were used to identify participants with baseline substantive cognitive impairment (SCI), defined as a baseline score on either the MoCA or DSST ≥ 1.5 SD below either score's country-specific mean, or SCI-GM, which was based on a composite index of both scores calculated as their geometric mean (GM), and defined as a score that was ≥ 1.5 SD below their country's average GM. Relationships between these measures and incident major adverse cardiovascular events (MACE), and either stroke or death were analyzed.

RESULTS

Compared with 7867 (89.7%) unaffected participants, the 905 (10.3%) participants with baseline SCI had a higher incidence of MACE (unadjusted hazard ratio [HR] 1.34; 95% CI 1.11, 1.62; P = 0.003), and stroke or death (unadjusted HR 1.60; 95% CI 1.33, 1.91; P < 0.001). Stronger relationships were noted for SCI-GM and MACE (unadjusted HR 1.61; 95% CI 1.28, 2.01; P < 0.001), and stroke or death (unadjusted HR 1.85; 95% CI 1.50, 2.30; P < 0.001). For SCI-GM but not SCI, all these relationships remained significant in models that adjusted for up to 10 SCI risk factors.

CONCLUSION

Country-standardized SCI-GM was a strong independent predictor of cardiovascular events in people with type 2 diabetes in the REWIND trial.

Effects of Intermittent Hypoxia-Hyperoxia Exposure Prior to Aerobic Cycling Exercise on Physical and Cognitive Performance in Geriatric Patients—A Randomized Controlled Trial

Background: It was recently shown that intermittent hypoxic-hyperoxic exposure (IHHE) applied prior to a multimodal training program promoted additional improvements in cognitive and physical performance in geriatric patients compared to physical training only. However, there is a gap in the literature to which extent the addition of IHHE can enhance the effects of an aerobic training. Therefore, the aim of this study was to investigate the efficacy of IHHE applied prior to aerobic cycling exercise on cognitive and physical performance in geriatric patients.

Methods: In a randomized, two-armed, controlled, and single-blinded trial, 25 geriatric patients (77–94 years) were assigned to two groups: intervention group (IG) and sham control group (CG). Both groups completed 6 weeks of aerobic training using a motorized cycle ergometer, three times a week for 20 min per day. The IG was additionally exposed to intermittent hypoxic and hyperoxic periods for 30 min prior to exercise. The CG followed the similar procedure breathing sham hypoxia and hyperoxia (i.e., normoxia). Within 1 week before and after the interventions, cognitive performance was assessed with the Dementia-Detection Test (DemTect) and the Clock Drawing Test (CDT), while physical performance was measured using the Timed “Up and Go” Test (TUG) and the Short-Physical-Performance-Battery (SPPB).

Results: No interaction effect was found with respect to the DemTect (η_p² = 0.02). An interaction effect with medium effect size (η_p² = 0.08) was found for CDT performance with a higher change over time for IG (d = 0.57) compared to CG (d = 0.05). The ANCOVA with baseline-adjustment indicated between-group differences with a large and medium effect size at post-test for the TUG (η_p² = 0.29) and SPPB (η_p² = 0.06) performance, respectively, in favour of the IG. Within-group post-hoc analysis showed that the TUG performance was worsened in the CG (d = 0.65) and remained unchanged in the IG (d = 0.19). Furthermore, SPPB performance was increased (d = 0.58) in IG, but no relevant change over time was found for CG (d = 0.00).

Conclusion: The current study suggests that an additional IHHE prior to aerobic cycling exercise seems to be more effective to increase global cognitive functions as well as physical performance and to preserve functional mobility in geriatric patients in comparison to aerobic exercise alone after a 6-week intervention period.

Assessment and Management of Cognitive Function in Patients with Prostate Cancer Treated with Second-Generation Androgen Receptor Pathway Inhibitors

Preservation of cognitive function is an important outcome in oncology. Optimal patient management requires an understanding of cognitive effects of the disease and its treatment and an efficacious approach to assessment and management of cognitive dysfunction, including selection of treatments to minimize the risk of cognitive impairment. Awareness is increasing of the potentially detrimental effects of cancer-related cognitive dysfunction on functional independence and quality of life. Prostate cancer occurs most often in older men, who are more likely to develop cognitive dysfunction than younger individuals; this population may be particularly vulnerable to treatment-related cognitive disorders. Prompt identification of treatment-induced cognitive dysfunction is a crucial aspect of effective cancer management. We review the potential etiologies of cognitive decline in patients with prostate cancer, including the potential role of androgen receptor pathway inhibitors; commonly used tools for assessing cognitive function validated in metastatic castration-resistant prostate cancer and adopted in non-metastatic castration-resistant prostate cancer trials; and strategies for management of cognitive symptoms. Many methods are currently used to assess cognitive function. The prevalence and severity of cognitive dysfunction vary according to the instruments and criteria applied. Consensus on the definition of cognitive dysfunction and on the most appropriate approaches to quantify its extent and progression in patients treated for prostate cancer is lacking. Evidence-based guidance on the appropriate tools and time to assess cognitive function in patients with prostate cancer is required.

Is simple reaction time or choice reaction time an indicator of all-cause mortality or CVD mortality?

OBJECTIVES

Simple reaction time (SRT) and choice reaction time (CRT) have been shown to be good indicators for quantitatively assessing the level of human cognitive impairment, but these parameters have also been linked to the risk of human death. This study aimed to quantitatively assess the independent predictive value of SRT or CRT for all-cause mortality or cardiovascular disease (CVD) mortality by conducting a meta-analysis of prospective studies.

STUDY DESIGN

The study design of this study is a prospective cohort study.

METHODS

We conducted a meta-analysis by combining hazard ratios (HRs) and 95% confidence intervals (95% CIs) of SRT or CRT with all-cause mortality or CVD mortality in healthy community residents aged 18 and over. Heterogeneity was evaluated by using Q statistics and Cochrane's I² statistics.

RESULTS

A total of seven prospective studies that examined all-cause mortality and CVD mortality were included. The pooled HR of all-cause mortality in SRT was 1.099 (1.065-1.134, I² = 11.9%), and an increased risk of CVD mortality was associated with lower SRT (HR = 1.186, 95% CI = 1.137-1.236; I² = 52.4%). Similarly, the pooled HR of all-cause mortality in CRT was 1.140 (95% CI = 1.085-1.197, I² = 33.7%). However, lower CRT was not statistically associated with an increased risk of CVD mortality.

CONCLUSION

SRT may be a predictor of all-cause-mortality and CVD mortality, and CRT is significantly associated with an increased risk of all-cause mortality.

Dementia Prevalence, Comorbidities, and Lifestyle Among Jatinangor Elders

Introduction: Research on dementia prevalence and the potentially related risk factors from Indonesia is scarce. We sought to identify the prevalence of dementia, health risk factors, and lifestyle in Jatinangor elders.

Methods: A total of 686 participants completed questionnaires on lifestyle, health risk factors, and cognitive and functional tests from September 2013 to December 2013. We determined the prevalence of dementia; and the associations between health, leisure activities, dietary pattern, and dementia were analyzed using logistic regression.

Results: The prevalence of dementia was 29.15%. The risk factors differed between age groups. Those aged 60–74 years and who have a lower education level, lower occupational attainment, and less active intellectual and recreational activities were associated with higher dementia risk. Those aged > 75 years living in a rural area and who take less fruit were associated with a higher risk of dementia.

Conclusions: The prevalence of dementia in Jatinangor is high. The identified modifiable risk factors are a potential target for intervention and valuable for designing public health policies.

Verbal memory is associated with adherence to COVID-19 protective behaviors in community dwelling older adults

Background

Adherence to protective behaviors is central to limiting the spread of COVID-19 and associated risk of serious illness and mortality in older populations. Whether cognition predicts adherence to protective behaviors has not been examined in older adults.

Aims

To examine whether specific cognitive abilities predict adherence to COVID-19 protective behaviors in older adults, independent of other relevant factors.

Methods

Data from 431 older adults (i.e., ≥ 65 years) who took part in the COVID-19 module of the Health and Retirement Study were included in the present study. Separate binary logistic regression models were used to examine whether performance on measures of immediate and delayed recall and working memory predicted adherence to COVID-19 protective behaviors, controlling for demographics, level of COVID-19 concern, depressive symptoms, and medical conditions.

Results

For every unit increase in immediate and delayed recall, the probability of adhering to COVID-19 protective behaviors increased by 47% and 69%, respectively. There was no association between the measure of working memory and adherence.

Discussion

It is of public interest to understand the factors that reduce adherence to protective behaviors so that we can better protect those most vulnerable and limit community spread. Our findings demonstrate that reduced memory predicts non-adherence to COVID-19 protective behaviors, independent of virus concern, and other relevant demographic and health factors.

Conclusions

Public health strategies aimed at increasing adherence to COVID-19 protective behaviors in community dwelling older adults, should account for the role of reduced cognitive function in limiting adherence.

Lowered cognitive function and the risk of the first events of cardiovascular diseases: findings from a cohort study in Lithuania

Background

The purpose of this prospective cohort study was to examine whether the level of cognitive function at the baseline expressed as a cognitive function composite score and score of specific domains predict the risk of first cardiovascular disease (CVD) events in middle-aged and older populations.

Methods

Seven thousand eighty-seven participants, men and women aged 45–72 years, were assessed in the baseline survey of the Health Alcohol Psychosocial Factors in Eastern Europe (HAPIEE) study in 2006–2008 in the city of Kaunas, Lithuania. During 10 years of follow-up, the risk of first non-fatal events of CVD and death from CVD (excluding those participants with a documented history of CVD and/or ischemic heart disease (IHD) diagnosed at the baseline survey) was evaluated. Cox proportional hazards regression models were applied to examine how cognitive function predicts the first events of CVD.

Results

During the follow-up, there were 156 deaths from CVD (49 women and 107 men) and 464 first non-fatal CVD events (195 women and 269 men) registered. The total number of first CVD events was 620 (11.5%). After adjustment for sociodemographic factors, biological and lifestyle risk factors and illnesses, a decrease per 1 standard deviation in different cognitive function scores significantly increased the risk of a first event of CVD (immediate verbal recall score - by 17% in men and 32% in women; delayed verbal recall score – by 17% in men and 24% in women; and a composite score of cognitive function – by 15% in men and 29% in women). Kaplan-Meier survival curves for the probability of a first cardiovascular event according to the categories of a composite score of cognitive function, revealed that a lowered cognitive function predicts a higher probability of the events compared to normal cognitive function (p < 0.05).

Conclusions

The findings of this follow-up study suggest that men and women with lower cognitive functions have an increased risk for a first event of CVD compared to participants with a higher level of cognitive functions.

Intelligence, health and death

The field of cognitive epidemiology studies the prospective associations between cognitive abilities and health outcomes. We review research in this field over the past decade and describe how our understanding of the association between intelligence and all-cause mortality has consolidated with the appearance of new, population-scale data. To try to understand the association better, we discuss how intelligence relates to specific causes of death, diseases/diagnoses and biomarkers of health through the adult life course. We examine the extent to which mortality and health associations with intelligence might be attributable to people's differences in education, other indicators of socioeconomic status, health literacy and adult environments and behaviours. Finally, we discuss whether genetic data provide new tools to understand parts of the intelligence-health associations. Social epidemiologists, differential psychologists and behavioural and statistical geneticists, among others, contribute to cognitive epidemiology; advances will occur by building on a common cross-disciplinary knowledge base.

The Relationship Between Cognitive Performance Using Tests Assessing a Range of Cognitive Domains and Future Dementia Diagnosis in a British Cohort: A Ten-Year Prospective Study

BACKGROUND

Exploring the domains of cognitive function which are most strongly associated with future dementia may help with understanding risk factors for, and the natural history of dementia.

OBJECTIVE

To examine the association of performance on a range of cognitive tests (both global and domain specific) with subsequent diagnosis of dementia through health services in a population of relatively healthy men and women and risk of future dementia.

METHODS

We examined the association between performance on different cognitive tests as well as a global score and future dementia risk ascertained through health record linkage in a cohort of 8,581 individuals (aged 48-92 years) between 2004-2019 with almost 15 years follow-up (average of 10 years) before and after adjustment for socio-demographic, lifestyle, and health characteristics.

RESULTS

Those with poor performance for global cognition (bottom 10%) were almost four times as likely to receive a dementia diagnosis from health services over the next 15 years than those who performed well HR = 3.51 (95% CI 2.61, 4.71 p < 0.001) after adjustment for socioeconomic, lifestyle, and biological factors and also prevalent disease. Poor cognition performance in multiple tests was associated with 10-fold increased risk compared to those not performing poorly in any test HR = 10.82 (95% CI 6.85, 17.10 p < 0.001).

CONCLUSION

Deficits across multiple cognitive domains substantially increase risk of future dementia over and above neuropsychological test scores ten years prior to a clinical diagnosis. These findings may help further understanding of the natural history of dementia and how such measures could contribute to strengthening future models of dementia.

Elderly Patients in the Intensive Care Unit

Very old intensive care unit (ICU) patients, aged ≥ 80 years, are by no mean newcomers, but during the last decades their impact on ICU admissions has grown in parallel with the increase in the number of elderly persons in the community. Hence, from being a "rarity," they have now become common and constitute one of the largest subgroups within intensive care, and may easily be the largest group in 20 years and make up 30 to 40% of all ICU admissions. Obviously, they are not admitted because they are old but because they are with various diseases and problems like any other ICU patient. However, their age and the presence of common geriatric syndromes such as frailty, cognitive decline, reduced activity of daily life, and several comorbid conditions makes this group particularly challenging, with a high mortality rate. In this review, we will highlight aspects of current and future epidemiology and current knowledge on outcomes, and describe the effects of the aforementioned geriatric syndromes. The major challenge for the coming decades will be the question of whom to treat and the quest for better triage criteria not based on age alone. Challenges with the level of care during the ICU stay will also be discussed. A stronger relationship with geriatricians should be promoted to create a better and more holistic care and aftercare for survivors.

Instrumented measures of sedentary behaviour and physical activity are associated with mortality in community-dwelling older adults: A systematic review, meta-analysis and meta-regression analysis

BACKGROUND

Sedentary behaviour (SB) and physical activity (PA) can be objectively assessed with inertial sensors to describe bodily movement. Higher SB and lower PA is associated with higher chronological age and negative health outcomes. This study aimed to quantify the association between instrumented measures of SB (i-SB) and PA (i-PA) and mortality in community-dwelling older adults, to subsequently compare the quantitative effect sizes and to determine the dose-response relationships.

METHODS

An electronic search in six databases from inception to 27th of June 2019 was conducted. All articles reporting on i-SB or i-PA and mortality in community-dwelling older adults aged 60 years or older were considered eligible. A meta-analysis was conducted for the association between i-SB and i-PA and mortality expressed in Hazard Ratios (HR) and 95% Confidence Intervals (95% CI). A meta-regression analysis was performed to determine the dose-response relationship between i-SB and steps per day and mortality.

RESULTS

Twelve prospective articles representing eleven cohorts, reporting data of 38,141 participants were included. In total 2502 (6.4%) participants died during follow-up (2.0 to 9.8 years). Comparing the most sedentary with the least sedentary groups of participants resulted in a pooled HR of 2.44 (95% CI 1.82-3.25). Comparing the least active with the most active groups of participants resulted in a pooled HR of 1.93 (95% CI 1.39-2.69); 2.66 (95% CI 2.11-3.35); 3.43 (95% CI 2.61-4.52), and 3.09 (95% CI 2.33-4.11) for light, moderate-to-vigorous-, total PA and steps per day, respectively. Meta-regression analyses showed clear dose-response relationships between i-SB and steps per day and mortality risk.

CONCLUSION

Both i-SB and i-PA are significantly associated with mortality in community-dwelling older adults, showing the largest effect size for total physical activity. Dose-response relationships could be observed for i-SB and steps per day.

Integration of an Objective Cognitive Assessment Into a Prognostic Index for 5-Year Mortality Prediction

BACKGROUND/OBJECTIVES

Prognostic indices rarely include cognition. We determined if a comprehensive cognitive screen or brief individual items were associated with improved mortality predictions of a widely used prognostic index.

DESIGN, SETTING, AND PARTICIPANTS

The National Social Life Health and Aging Project Wave 2, a nationally representative, cross-sectional, in-home survey conducted in 2010 to 2011 on 3,199 community-dwelling adults aged 60 to 99 years.

MEASUREMENTS

Cognition was measured using a Survey-Adapted Montreal Cognitive Assessment (MoCA-SA) grouped into three screened categories: screen normal (≥24 points), screen positive for mild cognitive impairment (18-23 points), and screen positive for dementia (<18 points). Single-item cognitive measures included clock-draw and five-word delayed recall. We constructed a modified Lee Prognostic Index (range = 0-18 points) based on age, behavior, function, and comorbidities shown to predict long-term mortality. We used logistic regression and the fraction of new information provided to determine if each cognitive measure improved the Lee index's 5-year mortality prediction.

RESULTS

The sample was 54% female and had a mean age of 72 years, MoCA-SA score of 22 (SD = 4.5), and Lee index of 7 (SD = 3). Regression analysis indicated the MoCA-SA modestly improved the Lee index's mortality prediction (P < .001; fraction of new information provided = 0.06); for low Lee index scores (<4 points), the absolute mortality rate difference was 7% by cognitive status; and for higher Lee index scores (4-7 points or 8-12 points), the absolute mortality rate difference was 15% by cognitive status. The clock-draw and delayed-recall items added similar value to mortality predictions as the longer MoCA-SA. Cognition had the third highest fraction of new information of all 13 Lee index items.

CONCLUSION

Incorporating a brief measure of cognition into a modified Lee index, even with single items, resulted in more accurate 5-year mortality risk predictions. Cognition should be included in prognostic calculators in older adults given its independent association with mortality risk. J Am Geriatr Soc 68:1796-1802, 2020.

PLCG2 protective variant p.P522R modulates tau pathology and disease progression in patients with mild cognitive impairment

A rare coding variant (rs72824905, p.P522R) conferring protection against Alzheimer's disease (AD) was identified in the gene encoding the enzyme phospholipase-C-γ2 (PLCG2) that is highly expressed in microglia. To explore the protective nature of this variant, we employed latent process linear mixed models to examine the association of p.P522R with longitudinal cognitive decline in 3595 MCI patients, and in 10,097 individuals from population-based studies. Furthermore, association with CSF levels of pTau181, total tau, and Aβ1-42 was assessed in 1261 MCI patients. We found that MCI patients who carried the p.P522R variant showed a slower rate of cognitive decline compared to non-carriers and that this effect was mediated by lower pTau181 levels in CSF. The effect size of the association of p.P522R with the cognitive decline and pTau181 was similar to that of APOE-ε4, the strongest genetic risk factor for AD. Interestingly, the protective effect of p.P522R was more pronounced in MCI patients with low Aβ1-42 levels suggesting a role of PLCG2 in the response to amyloid pathology. In line with this hypothesis, we observed no protective effect of the PLCG2 variant on the cognitive decline in population-based studies probably due to the lower prevalence of amyloid positivity in these samples compared to MCI patients. Concerning the potential biological underpinnings, we identified a network of co-expressed proteins connecting PLCG2 to APOE and TREM2 using unsupervised co-regulatory network analysis. The network was highly enriched for the complement cascade and genes differentially expressed in disease-associated microglia. Our data show that p.P522R in PLCG2 reduces AD disease progression by mitigating tau pathology in the presence of amyloid pathology and, as a consequence, maintains cognitive function. Targeting the enzyme PLCG2 might provide a new therapeutic approach for treating AD.

Unraveling the Association Between Gait and Mortality-One Step at a Time

BACKGROUND

Slowness of walking is one of the very first signs of aging and is considered a marker for overall health that is strongly associated with mortality risk. In this study, we sought to disentangle the clinical drivers of the association between gait and mortality.

METHODS

We included 4,490 participants of the Rotterdam Study who underwent a gait assessment between 2009 and 2015 and were followed-up for mortality until 2018. Gait was assessed with an electronic walkway and summarized into the domains Rhythm, Phases, Variability, Pace, Tandem, Turning, and Base of Support. Cox models adjusted for age, sex, and height were built and consecutively adjusted for six categories of health indicators (lifestyle, musculoskeletal, cardiovascular, pulmonary, metabolic, and neurological). Analyses were repeated in comorbidity-free individuals.

RESULTS

Multiple gait domains were associated with an increased risk of mortality, including Pace (hazard ratio (HR) per SD worse gait, adjusted for other domains: 1.34 [1.19-1.50]), Rhythm (HR: 1.12 [1.02-1.23]) and Phases (HR: 1.12 [1.03-1.21]). Similarly, a 0.1 m/s decrease in gait speed was associated with a 1.21 (1.15-1.27) times higher hazard of mortality (HR fully adjusted: 1.14 [1.08-1.20]). In a comorbidity-free subsample, the HR per 0.1 m/s decrease in gait speed was 1.25 (1.09-1.44). Cause-specific mortality analyses revealed an association between gait speed and multiple causes of death.

CONCLUSIONS

Several gait domains were associated with mortality risk, including Pace which primarily represents gait speed. The association between gait speed and mortality persisted after an extensive adjustment for covariates, suggesting that gait is a marker for overall health.

Objectives, design and main findings until 2020 from the Rotterdam Study

The Rotterdam Study is an ongoing prospective cohort study that started in 1990 in the city of Rotterdam, The Netherlands. The study aims to unravel etiology, preclinical course, natural history and potential targets for intervention for chronic diseases in mid-life and late-life. The study focuses on cardiovascular, endocrine, hepatic, neurological, ophthalmic, psychiatric, dermatological, otolaryngological, locomotor, and respiratory diseases. As of 2008, 14,926 subjects aged 45 years or over comprise the Rotterdam Study cohort. Since 2016, the cohort is being expanded by persons aged 40 years and over. The findings of the Rotterdam Study have been presented in over 1700 research articles and reports. This article provides an update on the rationale and design of the study. It also presents a summary of the major findings from the preceding 3 years and outlines developments for the coming period.

Cognitive Function and Mortality: Results from Kaunas HAPIEE Study 2006-2017

Background: The purpose of the study is to evaluate the association between cognitive function and risk of all-cause and cardiovascular disease mortality during 10 years of the follow-up. Methods: 7087 participants were assessed in the baseline survey of the Health Alcohol Psychosocial Factors in Eastern Europe (HAPIEE) study in 2006–2008. During 10 years of follow-up, all-cause and CVD mortality risk were evaluated. Results: During 10 years of follow-up, 768 (23%) men and 403 (11%) women died (239 and 107 from CVD). After adjustment for sociodemographic, biological, lifestyle factors, and illnesses, a decrease per 1 standard deviation in different cognitive function scores increased risk for all-cause mortality (by 13%–24% in men, and 17%–33% in women) and CVD mortality (by 19%–32% in men, and 69%–91% in women). Kaplan-Meier survival curves for all-cause and CVD mortality, according to tertiles of cognitive function, revealed that the lowest cognitive function (1st tertile) predicts shorter survival compared to second and third tertiles (p < 0.001). Conclusions: The findings of this follow-up study suggest that older participants with lower cognitive functions have an increased risk for all-cause and CVD mortality compared to older participants with a higher level of cognitive function.

Early-life socioeconomic status, adolescent cognitive ability, and cognition in late midlife: Evidence from the Wisconsin Longitudinal Study

Although the association between childhood socioeconomic status (SES) and late-life cognition is well-established, the mechanisms underlying this association are less clear. One important potential mediator seldom examined is adolescent cognitive ability. To address this gap, we examined 5,880 respondents from the Wisconsin Longitudinal Study, which follows a random sample of high school students who graduated from Wisconsin high schools in 1957. Structural equation models were used to examine the direct and indirect effects of childhood SES on cognition in late midlife through adolescent cognitive ability, educational attainment, midlife economic condition, and midlife health. Cognitive function was measured as a latent variable composed of scores from 6 cognitive assessments including immediate and delayed recall, digit ordering, letter and category fluency, and a subset of the Wechsler Adult Intelligence Scale similarities test. We found that childhood SES predicts cognition in late midlife, and this association is largely mediated by adolescent cognitive ability and educational attainment and to a lesser extent by midlife economic condition and health. The findings underscore the long-arm of childhood SES in cognitive function in later life and highlight the complex life-course pathways underlying the association between childhood SES and cognition.

The contribution of frailty, cognition, activity of daily life and comorbidities on outcome in acutely admitted patients over 80 years in European ICUs: the VIP2 study

Purpose

Premorbid conditions affect prognosis of acutely-ill aged patients. Several lines of evidence suggest geriatric syndromes need to be assessed but little is known on their relative effect on the 30-day survival after ICU admission. The primary aim of this study was to describe the prevalence of frailty, cognition decline and activity of daily life in addition to the presence of comorbidity and polypharmacy and to assess their influence on 30-day survival.

Methods

Prospective cohort study with 242 ICUs from 22 countries. Patients 80 years or above acutely admitted over a six months period to an ICU between May 2018 and May 2019 were included. In addition to common patients’ characteristics and disease severity, we collected information on specific geriatric syndromes as potential predictive factors for 30-day survival, frailty (Clinical Frailty scale) with a CFS > 4 defining frail patients, cognitive impairment (informant questionnaire on cognitive decline in the elderly (IQCODE) with IQCODE ≥ 3.5 defining cognitive decline, and disability (measured the activity of daily life with the Katz index) with ADL ≤ 4 defining disability. A Principal Component Analysis to identify co-linearity between geriatric syndromes was performed and from this a multivariable model was built with all geriatric information or only one: CFS, IQCODE or ADL. Akaike’s information criterion across imputations was used to evaluate the goodness of fit of our models.

Results

We included 3920 patients with a median age of 84 years (IQR: 81–87), 53.3% males). 80% received at least one organ support. The median ICU length of stay was 3.88 days (IQR: 1.83–8). The ICU and 30-day survival were 72.5% and 61.2% respectively. The geriatric conditions were median (IQR): CFS: 4 (3–6); IQCODE: 3.19 (3–3.69); ADL: 6 (4–6); Comorbidity and Polypharmacy score (CPS): 10 (7–14). CFS, ADL and IQCODE were closely correlated. The multivariable analysis identified predictors of 1-month mortality (HR; 95% CI): Age (per 1 year increase): 1.02 (1.–1.03, p = 0.01), ICU admission diagnosis, sequential organ failure assessment score (SOFA) (per point): 1.15 (1.14–1.17, p < 0.0001) and CFS (per point): 1.1 (1.05–1.15, p < 0.001). CFS remained an independent factor after inclusion of life-sustaining treatment limitation in the model.

Conclusion

We confirm that frailty assessment using the CFS is able to predict short-term mortality in elderly patients admitted to ICU. Other geriatric syndromes do not add improvement to the prediction model. Since CFS is easy to measure, it should be routinely collected for all elderly ICU patients in particular in connection to advance care plans, and should be used in decision making.

Electronic supplementary material

The online version of this article (10.1007/s00134-019-05853-1) contains supplementary material, which is available to authorized users.

Adherence to a healthy lifestyle counteracts the negative effects of risk factors on all-cause mortality in the oldest-old

In the study, we examined the extent to which the harmful effects of risk factors on all-cause mortality can be counteracted by healthy lifestyle practices in the oldest-old (80 years of age and older). A total of 17,660 oldest-old from China were followed up for up to 10 years. The data were analyzed using the Cox proportional hazard model with adjustment for potential confounders. We found that having a rural residence, not being married, having lower economic status, physical disability, impaired cognitive function, or comorbidity were all associated with an elevated risk of mortality. Using these factors, we computed a weighted "risk score." Because never smoking, never drinking, doing physical exercise, having an ideal diet, and a normal weight were independently associated with lower mortality, we also combined them to compute a weighted "protection score." Both scores were divided into lowest, middle, and highest groups using their tertiles. In joint effect analyses, participants with the combined highest-risk score and lowest-protection score profile had a nearly threefold higher joint death risk. These analyses show that adherence to a healthy lifestyle counteracts the negative effect of risk factors on all-cause mortality in the oldest-old by more than 20%.

Association of change in cognitive function from early adulthood to middle age with risk of cause-specific mortality: the Vietnam Experience Study

BACKGROUND

Studies with single baseline measurements of cognitive function consistently reveal inverse relationships with mortality risk. The relation of change in functioning, particularly from early in the life course, which may offer additional insights into causality, has not, to the best of our knowledge, been tested.

AIMS

To examine the association of change in cognition between late adolescence and middle age with cause-specific mortality using data from a prospective cohort study.

METHODS

The analytical sample consisted of 4289 former US male military personnel who were administered the Army General Technical Test in early adulthood (mean age 20.4 years) and again in middle age (mean age 38.3 years).

RESULTS

A 15-year period of mortality surveillance subsequent to the second phase of cognitive testing gave rise to 237 deaths. Following adjustment for age, a 10-unit increase in cognitive function was related to a reduced risk of death from all causes (HR 0.84; 95% CI 0.75 to 0.93) and cardiovascular disease (HR 0.78; 95% CI 0.64 to 0.95) but not from all cancers (HR 1.14; 95% CI 0.88 to 1.47) nor injury (HR 1.02; 95% CI 0.81 to 1.29). Adjustment for markers of socioeconomic status in middle age resulted in marked attenuation in the magnitude of these associations and statistical significance at conventional levels was lost in all analyses.

CONCLUSIONS

In the present study, the apparent link between increased cognition and mortality was mediated by socioeconomic status.