Multimorbidity burden and developmental trajectory in relation to later‐life dementia: A prospective study

Multimorbidity and risk of dementia: A systematic review and meta-analysis of longitudinal cohort studies

BACKGROUND

Chronic diseases (e.g., hypertension, diabetes, and heart diseases) have been proposed as marked predictors of incident dementia. However, synthesised evidence on the effect of multimorbidity on dementia is still lacking. We aim to summarise the association between multimorbidity and risk of dementia in longitudinal cohorts.

METHODS

In this systematic review and meta-analysis, we conducted a systematic search in PubMed, Web of Science and Embase from inception to Dec 14, 2024, to identify longitudinal cohort studies reporting the association between multimorbidity or multimorbidity patterns and risk of dementia. Information of included studies were extracted by three reviewers (YaZ, YY and YuZ), and the quality assessment was conducted using the Newcastle-Ottawa Scale. The inverse-variance weighted random effects meta-analysis was performed to obtain the pooled hazard ratios (HRs) and 95 % confidence intervals (CIs) for dementia associated with multimorbidity and cardiometabolic multimorbidity (CMM). Cochran's Q test and the I2 statistic were used to indicate heterogeneity among the studies. Meta-regression analysis, subgroup analysis and sensitivity analysis were conducted to determine any valid sources of heterogeneity. This study was registered with PROSPERO (CRD42023403684).

RESULTS

We included 17 longitudinal cohort studies (2262,885 middle-aged and older participants) in the systematic review, of which seven were included in meta-analysis. All studies presented moderate to high methodological quality. Meta-analysis showed a positive association between multimorbidity and incident dementia (HR=1.53, 95 % CI=1.12 to 2.09), with substantial heterogeneity (I2=95.2 %). Studies using health records to measure dementia tend to find a stronger positive relationship between multimorbidity and risk of dementia than those using self-report (HRhealth records=1.94, 95 % CI=1.35 to 2.78, I2=94 %; HRself-report=1.17, 95 % CI=1.07 to 1.28, I2=0 %). The impacts of CMM were also observed, and the HRs for dementia ranged from 2.49 (combination of heart diseases and stroke: 95 % CI=1.64 to 3.78) to 3.77 (combination of diabetes, heart diseases and stroke: 95 % CI=2.02 to 7.02). The heterogeneity was moderate, with I2 ranging from 46.9 % (p for heterogeneity=0.152) to 84.1 % (p for heterogeneity=0.002). The impacts of number of diseases, multimorbidity clusters, and multimorbidity trajectory on risk of dementia were narratively summarised due to lacking comparable studies. Limited evidence (only one study) precluded quantitative synthesis for the association of physical and psychological multimorbidity with dementia.

CONCLUSION

Multimorbidity and CMM pattern were significantly associated with risk of dementia, while the effect of physical and psychological multimorbidity remain inconclusive. Individuals affected by multimorbidity should be prioritised in risk factor modification and dementia prevention. Preventing the development of multimorbidity is also crucial-particularly those who already have one chronic disease-in order to maintain cognitive health.

Association between multimorbidity and the risk of dementia: A systematic review and meta-analysis

BACKGROUND

Multimorbidity has become increasingly prevalent and poses challenges in managing cognitive function. This study aimed to (1) systematically review and perform a meta-analysis to understand the relationship between multimorbidity and the risk of dementia and (2) examine the impact of different multimorbidity patterns on this relationship.

METHOD

A systematic review was conducted using PubMed, Embase, PsychINFO, CINAHL, and Cochrane Central to gather studies published up to December 16, 2023. For the meta-analysis, studies with consistent study designs, multimorbidity definitions, and stages of dementia were included. Heterogeneity was assessed using the I2 statistic, and Egger's and Begg's tests were used to evaluate publication bias.

RESULTS

Of the 12,074 studies identified, 11 were deemed suitable for systematic review, and eight were included in the meta-analysis. Meta-analysis of the longitudinal studies revealed that baseline multimorbidity was significantly associated with an increased risk of dementia compared with individuals without multimorbidity (HR: 1.34, 95 % CI: 1.08-1.68). Meta-analysis of the cross-sectional studies indicated that multimorbidity was significantly associated with a higher risk of being in the prodromal stages of dementia than in individuals without multimorbidity (OR: 1.32, 95 % CI: 1.16-1.51). The risk of dementia varied according to diverse multimorbidity patterns, and the cardiovascular-metabolic condition-related patterns were the most common and associated with high dementia risk.

CONCLUSIONS

Our findings provide quantitative evidence of a significant association between multimorbidity and the risk of dementia. To develop effective dementia prevention strategies, an in-depth understanding of specific multimorbidity patterns is invaluable for managing cognitive function.

Assessment of Cognitive Functions in Multimorbid Patients in Lithuanian Primary Care Settings: A Cross-Sectional Study Using MMSE and LT-GPCOG

Background and Objectives: The aging population has led to a rise in cognitive impairments, including dementia, often associated with multimorbidity. Early diagnosis of cognitive decline is crucial, especially in primary care, where time constraints and the limitations of diagnostic tools may hinder accurate detection. This study aims to assess the cognitive functions of multimorbid patients using the Mini-Mental State Examination (MMSE) and the Lithuanian version of the General Practitioner Assessment of Cognition (LT-GPCOG). We hypothesized that the LT-GPCOG would perform similarly to the MMSE in suspecting cognitive impairments. Materials and Methods: This cross-sectional study, conducted from 2021 to 2022, included 796 patients aged 40-85, with arterial hypertension and at least one other chronic disease, recruited from seven Lithuanian primary health care centers. Cognitive function was assessed using the MMSE and LT-GPCOG, and statistical analyses were performed using SPSS to determine the association between cognitive impairment and various demographic and clinical variables. Results: Out of 796 participants, 793 completed the study. Cognitive impairment was suspected in 5.1% of participants based on MMSE and 4.2% based on the LT-GPCOG. Statistically significant associations were found between cognitive impairment and chronic obstructive pulmonary disease (COPD) (p = 0.008 and p = 0.003) in both tests and chronic kidney disease (CKD) (p = 0.005) while testing with the MMSE. Lower education and unemployment were also correlated with cognitive impairment (p = 0.008 and p < 0.001). Conclusions: The findings suggest that regular cognitive assessments should be integrated into the management of multimorbid patients, particularly those with COPD and CKD. The LT-GPCOG proved to be an efficient alternative to the MMSE in primary care settings, demonstrating comparable diagnostic accuracy. Further studies are also needed to assess the sensitivity and specificity of the LT-GPCOG test.

Socioeconomic inequality in the multimorbidity trajectories of middle-aged and older adults in China: A prospective cohort study

OBJECTIVE

The prevalence of multimorbidity is socially patterned, but little is known about how socioeconomic inequality might affect the long-term progression of multimorbidity. This study aimed to identify multimorbidity trajectories and to examine their association with socioeconomic status (SES) among middle-aged and older Chinese adults.

METHODS

A total of 3837 middle-aged and older participants were included from the dynamic cohort of the China Health and Retirement Longitudinal Study, 2011-2018. Multimorbidity trajectories were assessed using the Chinese Multimorbidity-Weighted Index (CMWI), which covers 14 chronic conditions. Group-based trajectory modeling was used to identify multimorbidity developmental trajectories. Education, working status, and total household income were used to construct SES scores. The associations between SES and CMWI trajectories were estimated using multinomial logistic regression models adjusting for sociodemographic and lifestyle factors.

RESULTS

Four distinct CMWI trajectories were identified: 'no multimorbidity' (16.8 %), 'new-onset multimorbidity' (48.7 %), 'slowly increasing multimorbidity' (24.3 %), and 'rapidly increasing multimorbidity' (10.2 %). Lower SES was associated with higher odds of experiencing the 'rapidly increasing' trajectory (P trend < 0.01); for example, compared with the 'no multimorbidity' group, participants with low SES had a 96 % (OR, 1.96; 95 % CI, 1.29 to 2.98) increased odds of belonging to the 'rapidly increasing' group.

CONCLUSION

Socioeconomic inequalities were observed in the CMWI trajectories of multimorbidity in middle-aged and older Chinese adults. The findings suggest effective strategies for preventing and controlling multimorbidity should be made from a long-term perspective, especially for those of lower SES.

The mechanisms, hallmarks, and therapies for brain aging and age-related dementia

Age-related cognitive decline and dementia are significant manifestations of brain aging. As the elderly population grows rapidly, the health and socio-economic impacts of cognitive dysfunction have become increasingly significant. Although clinical treatment of dementia has faced considerable challenges over the past few decades, with limited breakthroughs in slowing its progression, there has been substantial progress in understanding the molecular mechanisms and hallmarks of age-related dementia (ARD). This progress brings new hope for the intervention and treatment of this disease. In this review, we categorize the latest findings in ARD biomarkers into four stages based on disease progression: Healthy brain, pre-clinical, mild cognitive impairment, and dementia. We then systematically summarize the most promising therapeutic approaches to prevent or slow ARD at four levels: Genome and epigenome, organelle, cell, and organ and organism. We emphasize the importance of early prevention and detection, along with the implementation of combined treatments as multimodal intervention strategies, to address brain aging and ARD in the future.

Comparison of seven models for the progression patterns of multiple chronic conditions in longitudinal studies

Introduction

Studies investigating the relationship between patterns of multimorbidity and risk of a new condition have typically defined the patterns at a baseline time and used Kaplan-Meier (KM) or Cox proportional hazards regression. These methods do not consider the competing risk of death or the changes in the patterns of conditions over time. This study illustrates how these methodological limitations can be overcome in the setting of progression from cardiometabolic conditions to dementia.

Methods

Data from 11 930 women who participated in the Australian Longitudinal Study on Women's Health were used to define patterns of diabetes, heart disease and stroke and estimate the cumulative incidence or HRs of subsequent dementia. Seven methods were compared. For cumulative incidence these were KM method, cumulative incidence function (CIF) (to account for the competing risk of death) and multistate model with Aalen-Johansen estimates (to account also for the progression of conditions over time). For HRs, the corresponding methods were Cox model and Fine and Gray model (for sub-HRs) with the cardiometabolic patterns treated as time-invariant (from baseline) or as time-varying predictors.

Results

The estimated cumulative incidence of dementia using the KM method declined when the competing risk of death was considered. For example, for women with no cardiometabolic condition at baseline, the KM and CIF estimates were 35.7% (95% CI 34.6%, 36.8%) and 27.3% (26.4%, 28.2%) but these women may have developed cardiometabolic conditions during the study which would increase their risk. The Aalen-Johansen multistate estimate for women with no cardiometabolic condition over the whole study period was 11.0% (10.4%, 11.7%). Comparing models to estimate HRs, the estimates in the Fine and Gray models were lower than those in the Cox models.

Conclusions

Multistate and time-varying survival analysis models should be used to study the natural development of multimorbidity.

Disease trajectories before dementia: evidence from a large-scale community-based prospective study

BACKGROUND

Systemic changes in multiple diseases may influence the onset of dementia. However, the specific temporality between exposure diseases and dementia remains uncertain.

AIMS

By characterising the full spectrum of temporal disease trajectories before dementia, this study aims to yield a global picture of precursor diseases to dementia and to provide detailed instructions for risk management and primary prevention of dementia.

METHOD

Using the multicentre, community-based prospective UK Biobank, we constructed disease trajectories before dementia utilising the phenome-wide association analysis, paired directional test and association quantification. Stratified disease trajectories were constructed by dementia subtypes, gender, age of diagnosis and Apolipoprotein E (ApoE) status, respectively.

RESULTS

Our study population comprised 434 266 participants without baseline dementia and 4638 individuals with all-cause dementia. In total, 1253 diseases were extracted as potential components of the disease trajectory before dementia. We identified three clusters of disease trajectories preceding all-cause dementia, initiated by circulatory, metabolic and respiratory diseases occurring approximately 5-15 years before dementia. Cerebral infarction or chronic renal failure following chronic ischaemic heart disease was the specific trajectory before vascular dementia. Apolipoprotein E (ApoE) ε4 non-carriers exhibited more complex trajectories compared with carriers. Lipid metabolism disorders remained in the trajectories regardless of dementia subtypes, gender, age of diagnosis and ApoE status.

CONCLUSIONS

This study provides a comprehensive view of the longitudinal disease trajectories before dementia and highlights the potential targets of midlife cardiometabolic dysfunction for dementia screening and prevention.

A comparative retrospective longitudinal study of arthritis risk and cognitive decline in older adults

Arthritis often results in unmet healthcare needs for older adults with cognitive decline, who may struggle to communicate pain or recall symptoms. However, the risk factors for arthritis in this group remain underexplored. We addressed this gap by identifying and comparing arthritis risk factors among older adults with varying cognitive statuses. Data from 334 participants with cognitive decline and 808 participants with normal cognition were analysed using the Korean Longitudinal Study of Aging, tracking arthritis diagnoses over 12 years with Kaplan-Meier curves and Cox proportional hazards regression. Results showed 47.6% of older adults with cognitive decline developed arthritis, compared with 30.1% with normal cognition. Key risk factors for the cognitive decline group included depressive symptoms (hazard ratio [HR]: 1.87), living alone (HR: 1.66), infrequent social interactions (HR: 1.42), and greater dependency in daily activities (HR: 1.41). In the normal cognition group, additional chronic illnesses (HR: 1.41) and higher body mass index (HR: 1.09) were significant risk factors. Understanding these distinct risk factors is crucial for preventing and managing arthritis among at risk groups. Moreover, these findings can assist in developing comprehensive public health strategies integrating mental health and social support to improve health outcomes for older adults with cognitive decline.

Clinical trajectories preceding incident dementia up to 15 years before diagnosis: a large prospective cohort study

BACKGROUND

Dementia has a long prodromal stage with various pathophysiological manifestations; however, the progression of pre-diagnostic changes remains unclear. We aimed to determine the evolutional trajectories of multiple-domain clinical assessments and health conditions up to 15 years before the diagnosis of dementia.

METHODS

Data was extracted from the UK-Biobank, a longitudinal cohort that recruited over 500,000 participants from March 2006 to October 2010. Each demented subject was matched with 10 healthy controls. We performed logistic regressions on 400 predictors covering a comprehensive range of clinical assessments or health conditions. Their evolutional trajectories were quantified using adjusted odds ratios (ORs) and FDR-corrected p-values under consecutive timeframes preceding the diagnosis of dementia.

FINDINGS

During a median follow-up of 13.7 [Interquartile range, IQR 12.9-14.2] years until July 2022, 7620 subjects were diagnosed with dementia. In general, upon approaching the diagnosis, demented subjects witnessed worse functional assessments and a higher prevalence of health conditions. Associations up to 15 years preceding the diagnosis comprised declined physical strength (hand grip strength, OR 0.65 [0.63-0.67]), lung dysfunction (peak expiratory flow, OR 0.78 [0.76-0.81]) and kidney dysfunction (cystatin C, OR 1.13 [1.11-1.16]), comorbidities of coronary heart disease (OR 1.78 [1.67-1.91]), stroke (OR 2.34 [2.1-1.37]), diabetes (OR 2.03 [1.89-2.18]) and a series of mental disorders. Cognitive functions in multiple tests also demonstrate decline over a decade before the diagnosis. Inadequate activity (3-5 year, overall time of activity, OR 0.82 [0.73-0.92]), drowsiness (3-5 year, sleep duration, OR 1.13 [1.04-1.24]) and weight loss (0-5 year, weight, OR 0.9 [0.83-0.98]) only exhibited associations within five years before the diagnosis. In addition, serum biomarkers of enriched endocrine, dysregulations of ketones, deficiency of brand-chain amino acids and polyunsaturated fatty acids were found in a similar prodromal time window and can be witnessed as the last pre-symptomatic conditions before the diagnosis.

INTERPRETATION

Our findings present a comprehensive temporal-diagnostic landscape preceding incident dementia, which could improve selection for preventive and early disease-modifying treatment trials.

Multimorbidity measures associated with cognitive function among community-dwelling older Chinese adults

INTRODUCTION

Older adults with multimorbidity are at high risk of cognitive impairment development. There is a lack of research on the associations between different multimorbidity measures and cognitive function among older Chinese adults living in the community.

METHODS

We used the Chinese Longitudinal Healthy Longevity Survey from 2002 to 2018 and included data on dementia-free participants aged ≥65 years. Multimorbidity measures included condition counts, multimorbidity patterns, and trajectories. The association of multimorbidity measures with cognitive function was examined by generalized estimating equation and linear and logistic regression models.

RESULTS

Among 14,093 participants at baseline, 43.2% had multimorbidity. Multimorbidity patterns were grouped into cancer-inflammatory, cardiometabolic, and sensory patterns. Multimorbidity trajectories were classified as "onset-condition," "newly developing," and "severe condition." The Mini-Mental State Examination scores were significantly lower for participants with more chronic conditions, with cancer-inflammatory/cardiometabolic/sensory patterns, and with developing multimorbidity trajectories.

DISCUSSION

Condition counts, sensory pattern, cardiometabolic pattern, cancer-inflammatory pattern, and multimorbidity developmental trajectories were prospectively associated with cognitive function.

HIGHLIGHTS

Elderly individuals with a higher number of chronic conditions were associated with lower MMSE scores in the Chinese Longitudinal Healthy Longevity Survey data. MMSE scores were significantly lower for participants with specific multimorbidity patterns. Individuals with developing trajectories of multimorbidity were associated with lower MMSE scores and a higher risk of mild cognitive impairment.

Changes in patterns of multimorbidity and associated with medical costs among Chinese middle-aged and older adults from 2013 to 2023: an analysis of repeated cross-sectional surveys in Xiangyang, China

Background

Multimorbidity has become a major public health problem among Chinese middle-aged and older adults, and the most costly to the health care system. However, most previous population-based studies of multimorbidity have focused on a limited number of chronic diseases, and diagnosis was based on participants' self-report, which may oversimplify the problem. At the same time, there were few reports on the relationship between multimorbidity patterns and health care costs. This study analyzed the multimorbidity patterns and changes among middle-aged and older people in China over the past decade, and their association with medical costs, based on representative hospital electronic medical record data.

Methods

Two cross-sectional surveys based on representative hospital data were used to obtain adults aged 45 years and older in Xiangyang in 2013 (n = 20,218) and 2023 (n = 63,517). Latent Class Analysis was used to analyze changes in the patterns of multimorbidity, gray correlation analysis and ordered logistics model were used to assess the association of multimorbidity patterns with medical expenses. The diagnosis and classification of chronic diseases were based on the International Classification of Diseases, Tenth Revision codes (ICD-10).

Results

The detection rate of chronic disease multimorbidity has increased (70.74 vs. 76.63%, p < 0.001), and multimorbidity patterns have increased from 6 to 9 (2013: Malignant tumors pattern, non-specific multimorbidity pattern, ischemic heart disease + hypertension pattern, cerebral infarction + hypertension pattern, kidney disease + hypertension pattern, lens disease + hypertension pattern; new in 2023: Nutritional metabolism disorders + hypertension pattern, chronic lower respiratory diseases + malignant tumors pattern, and gastrointestinal diseases pattern) in China. The medical cost of all multimorbidity patients have been reduced between 2013 and 2023 (RMB: 8216.74 vs. 7247.96, IQR: 5802.28-15,737 vs. 5014.63-15434.06). The top three specific multimorbidity patterns in both surveys were malignancy tumor pattern, ischemic heart disease + hypertension pattern, and cerebral infarction + hypertension pattern. Hypertension and type 2 diabetes are important components of multimorbidity patterns. Compared with patients with a single disease, only lens disorders + hypertension pattern were at risk of higher medical costs in 2013 (aOR:1.23, 95% CI: 1.03, 1.47), whereas all multimorbidity patterns were significantly associated with increased medical costs in 2023, except for lens disorders + hypertension (aOR:0.35, 95% CI: 0.32, 0.39). Moreover, the odds of higher medical costs were not consistent across multimorbidity patterns. Among them, ischemic heart disease + hypertension pattern [adjusted odds ratio (aOR):4.66, 95%CI: 4.31, 5.05] and cerebral infarction + hypertension pattern (aOR: 3.63, 95% CI: 3.35, 3.92) were the two patterns with the highest risk. Meanwhile, men (aOR:1.12, 95CI:1.09, 1.16), no spouse (aOR:1.09, 95CI: 1.03, 1.16) had a positive effect on medical costs, while patients with total self-pay (aOR: 0.45, 95CI: 0.29, 0.70), no surgery (aOR: 0.05, 95CI: 0.05, 0.05), rural residence (aOR: 0.92, 95CI: 0.89, 0.95), hospitalization days 1-5 (aOR: 0.04, 95CI: 0.04, 0.04), and hospitalization days 6-9 (aOR: 0.15, 95CI: 0.15, 0.16) had a negative impact on medical costs.

Conclusion

Multimorbidity patterns among middle-aged and older adults in China have diversified over the past decade and are associated with rising health care costs in China. Smart, decisive and comprehensive policy and care interventions are needed to effectively manage NCDS and their risk factors and to reduce the economic burden of multimorbidity on patients and the country.

Essential New Complexity-Based Themes for Patient-Centered Diagnosis and Treatment of Dementia and Predementia in Older People: Multimorbidity and Multilevel Phenomenology

Dementia is a highly prevalent condition with devastating clinical and socioeconomic sequela. It is expected to triple in prevalence by 2050. No treatment is currently known to be effective. Symptomatic late-onset dementia and predementia (SLODP) affects 95% of patients with the syndrome. In contrast to trials of pharmacological prevention, no treatment is suggested to remediate or cure these symptomatic patients. SLODP but not young onset dementia is intensely associated with multimorbidity (MUM), including brain-perturbating conditions (BPCs). Recent studies showed that MUM/BPCs have a major role in the pathogenesis of SLODP. Fortunately, most MUM/BPCs are medically treatable, and thus, their treatment may modify and improve SLODP, relieving suffering and reducing its clinical and socioeconomic threats. Regrettably, the complex system features of SLODP impede the diagnosis and treatment of the potentially remediable conditions (PRCs) associated with them, mainly due to failure of pattern recognition and a flawed diagnostic workup. We suggest incorporating two SLODP-specific conceptual themes into the diagnostic workup: MUM/BPC and multilevel phenomenological themes. By doing so, we were able to improve the diagnostic accuracy of SLODP components and optimize detecting and favorably treating PRCs. These revolutionary concepts and their implications for remediability and other parameters are discussed in the paper.

Trajectories in long-term condition accumulation and mortality in older adults: a group-based trajectory modelling approach using the English Longitudinal Study of Ageing

OBJECTIVES

To classify older adults into clusters based on accumulating long-term conditions (LTC) as trajectories, characterise clusters and quantify their associations with all-cause mortality.

DESIGN

We conducted a longitudinal study using the English Longitudinal Study of Ageing over 9 years (n=15 091 aged 50 years and older). Group-based trajectory modelling was used to classify people into clusters based on accumulating LTC over time. Derived clusters were used to quantify the associations between trajectory memberships, sociodemographic characteristics and all-cause mortality by conducting regression models.

RESULTS

Five distinct clusters of accumulating LTC trajectories were identified and characterised as: 'no LTC' (18.57%), 'single LTC' (31.21%), 'evolving multimorbidity' (25.82%), 'moderate multimorbidity' (17.12%) and 'high multimorbidity' (7.27%). Increasing age was consistently associated with a larger number of LTCs. Ethnic minorities (adjusted OR=2.04; 95% CI 1.40 to 3.00) were associated with the 'high multimorbidity' cluster. Higher education and paid employment were associated with a lower likelihood of progression over time towards an increased number of LTCs. All the clusters had higher all-cause mortality than the 'no LTC' cluster.

CONCLUSIONS

The development of multimorbidity in the number of conditions over time follows distinct trajectories. These are determined by non-modifiable (age, ethnicity) and modifiable factors (education and employment). Stratifying risk through clustering will enable practitioners to identify older adults with a higher likelihood of worsening LTC over time to tailor effective interventions to prevent mortality.

SLEEPWISE: A Continuous Sleep Monitoring and Cognitive Evaluation Platform in Ambient Residential Environment

Age-related cognitive decline presents a significant health challenge for older adults, with no specific medication available to counteract it. Early detection of cognitive decline is crucial for timely intervention and effective management. Sleep status plays a vital role in evaluating cognitive function, as disrupted sleep patterns are associated with cognitive decline and increased risk of neurodegenerative conditions. Existing methods for assessing sleep status, such as self-report questionnaires, actigraphy, and polysomnography, lack the ability to consistently monitor sleep status over a long period. In this paper we introduced SLEEPWISE, an AI-powered platform deployed in residential environments for continuous ambient sleep monitoring to assess the cognitive well-being of older adults. SLEEPWISE utilizes non-contact pads with highly sensitive piezoelectric sensors to monitor sleep parameters such as duration and efficiency, which are transmitted daily to the server. Moreover, we have also developed a gamified module for SLEEPWISE, allowing an objective assessment of daily cognitive functions. This module aids SLEEPWISE in establishing the correlation models between sleep and cognitive health. To evaluate the effectiveness of SLEEP-WISE, a pilot study was conducted with participants recruited from a local hospital. During the 30-days trials, SLEEPWISE identified a negative impact on congnitive performance associated with increased nocturnal body movements and getting out of bad. These findings emphasize the potential of SLEEPWISE as an early screening tool for evaluating daily cognitive health and well-being.

Association of lifestyles and multimorbidity with mortality among individuals aged 60 years or older: Two prospective cohort studies

Lifestyles are associated with all-cause mortality, yet limited research has explored the association in the elderly population with multimorbidity. We aim to investigate the impact of adopting a healthy lifestyle on reducing the risk of all-cause mortality in older individuals with or without multimorbidity in both China and UK. This prospective study included 29,451 and 173,503 older adults aged 60 and over from Chinese Longitudinal Healthy Longevity Survey (CLHLS) and UK Biobank. Lifestyles and multimorbidity were categorized into three groups, respectively. Cox proportional hazards regression was used to estimate the Hazard Ratios (HRs), 95% confidence intervals (95% CIs), and dose-response for all-cause mortality in relation to lifestyles and multimorbidity, as well as the combination of both factors. During a mean follow-up period of 4.7 years in CLHLS and 12.14 years in UK Biobank, we observed 21,540 and 20,720 deaths, respectively. For participants with two or more conditions, compared to those with an unhealthy lifestyle, adopting a healthy lifestyle was associated with a 27%-41% and 22%-42% reduction in mortality risk in the CLHLS and UK Biobank, respectively; Similarly, for individuals without multimorbidity, this reduction ranged from 18% to 41%. Among participants with multimorbidity, individuals with an unhealthy lifestyle had a higher mortality risk compared to those maintaining a healthy lifestyle, with HRs of 1.15 (95% CI: 1.00, 1.32) and 1.27 (95% CI: 1.16, 1.39) for two conditions, and 1.24 (95% CI: 1.06, 1.45) and 1.73 (95% CI: 1.56, 1.91) for three or more conditions in CLHLS and UK Biobank, respectively. Adherence to a healthy lifestyle can yield comparable mortality benefits for older individuals, regardless of their multimorbidity status. Furthermore, maintaining a healthy lifestyle can alleviate the mortality risks linked to a higher number of diseases.

Mental-somatic multimorbidity in trajectories of cognitive function for middle-aged and older adults

INTRODUCTION

Multimorbidity may confer higher risk for cognitive decline than any single constituent disease. This study aims to identify distinct trajectories of cognitive impairment probability among middle-aged and older adults, and to assess the effect of changes in mental-somatic multimorbidity on these distinct trajectories.

METHODS

Data from the Health and Retirement Study (1998-2016) were employed to estimate group-based trajectory models identifying distinct trajectories of cognitive impairment probability. Four time-varying mental-somatic multimorbidity combinations (somatic, stroke, depressive, stroke and depressive) were examined for their association with observed trajectories of cognitive impairment probability with age. Multinomial logistic regression analysis was conducted to quantify the association of sociodemographic and health-related factors with trajectory group membership.

RESULTS

Respondents (N = 20,070) had a mean age of 61.0 years (SD = 8.7) at baseline. Three distinct cognitive trajectories were identified using group-based trajectory modelling: (1) Low risk with late-life increase (62.6%), (2) Low initial risk with rapid increase (25.7%), and (3) High risk (11.7%). For adults following along Low risk with late-life increase, the odds of cognitive impairment for stroke and depressive multimorbidity (OR:3.92, 95%CI:2.91,5.28) were nearly two times higher than either stroke multimorbidity (OR:2.06, 95%CI:1.75,2.43) or depressive multimorbidity (OR:2.03, 95%CI:1.71,2.41). The odds of cognitive impairment for stroke and depressive multimorbidity in Low initial risk with rapid increase or High risk (OR:4.31, 95%CI:3.50,5.31; OR:3.43, 95%CI:2.07,5.66, respectively) were moderately higher than stroke multimorbidity (OR:2.71, 95%CI:2.35, 3.13; OR: 3.23, 95%CI:2.16, 4.81, respectively). In the multinomial logistic regression model, non-Hispanic Black and Hispanic respondents had higher odds of being in Low initial risk with rapid increase and High risk relative to non-Hispanic White adults.

CONCLUSIONS

These findings show that depressive and stroke multimorbidity combinations have the greatest association with rapid cognitive declines and their prevention may postpone these declines, especially in socially disadvantaged and minoritized groups.

Caregivers' Burden on Patients with Dementia Having Multiple Chronic Diseases

Purpose

This study aimed to find the caregiving burden level for patients with dementia who had multiple chronic diseases by simultaneously considering both patient and caregiver factors.

Participants and Methods

A cross-sectional study with 284 patients with dementia having multiple chronic diseases managed by the dementia collaborative care team at Changhua Christian Hospital in Taiwan was conducted. The input variables were from patients, such as age, gender, mood symptoms, and behavioral and psychological symptoms, and caregivers, including age, relation to the patient, caregiver's mood, and caregiving burden. The Apriori algorithm was employed to determine the association between patient and caregiver factors and different caregiving burden levels by setting up the minimum support of 1% and confidence of 90% along with lift >1.

Results

When caring for patients with dementia, twenty scenarios were found for caregivers with a severe burden. In addition, 1936 scenarios were related to caregivers with a moderate-to-severe burden. Specifically, there were eight scenarios for patients with three chronic diseases which could be further categorized into five general rules. Two hundred and fifty scenarios belonging to patients with two chronic diseases could be classified into 16 different combinations from eight chronic diseases of the database.

Conclusion

Caregiver's mood, patients with mild dementia, and patients aged 75-84 years were associated with a severe caregiving burden. College and above education of the caregiver, the patient aged 85 years or more, and at least one of caregiver's moods were the variables to result in a moderate-to-severe burden for caregivers caring for patients with three multiple chronic diseases. Moreover, college and above education of the caregiver, mood symptom, age of the caregiver, and age of the patient were important variables for caregivers who had a moderate-to-severe burden taking care of patients with two chronic diseases.

Multimorbidity, cognitive phenotypes, and Alzheimer's disease plasma biomarkers in older adults: A population-based study

INTRODUCTION

To examine the burden and clusters of multimorbidity in association with mild cognitive impairment (MCI), dementia, and Alzheimer's disease (AD)-related plasma biomarkers among older adults.

METHODS

This population-based study included 5432 participants (age ≥60 years); of these, plasma amyloid beta (Aβ), total tau, and neurofilament light chain (NfL) were measured in a subsample (n = 1412). We used hierarchical clustering to generate five multimorbidity clusters from 23 chronic diseases. We diagnosed dementia and MCI following international criteria. Data were analyzed using logistic and linear regression models.

RESULTS

The number of chronic diseases was associated with dementia (multivariable-adjusted odds ratio = 1.22; 95% confidence interval [CI] = 1.11 to 1.33), AD (1.13; 1.01 to 1.26), vascular dementia (VaD) (1.44; 1.25 to 1.64), and non-amnestic MCI (1.25; 1.13 to 1.37). Metabolic cluster was associated with VaD and non-amnestic MCI, whereas degenerative ocular cluster was associated with AD (p < 0.05). The number of chronic diseases was associated with increased plasma Aβ and NfL (p < 0.05).

DISCUSSION

Multimorbidity burden and clusters are differentially associated with subtypes of dementia and MCI and AD-related plasma biomarkers in older adults.

HIGHLIGHTS

We used hierarchical clustering to generate five clusters of multimorbidity. The presence and load of multimorbidity were associated with dementia and mild cognitive impairment. Multimorbidity clusters were differentially associated with subtypes of dementia and Alzheimer's disease plasma biomarkers.

Gender-specific association of the accumulation of chronic conditions and disability in activities of daily living with depressive symptoms

BACKGROUND

In the era of rapid aging with a rising prevalence of multimorbidity, complex interactions between physical and psychological conditions have challenged the health care system. However, little is known about the association of the accumulation of chronic conditions and disability in activities of daily living with depressive symptoms, especially in developed countries.

METHODS

This population-based cohort study used data from the Health and Retirement Study. A total of 22,335 middle-aged and older adults participated in the 2014 (T1), 2016 (T2), and 2018 (T3) waves of the cohort were included. The accumulation of chronic conditions and disability were defined as the number of chronic diseases and the five activities of daily living. Depressive symptoms were measured by the Center for Epidemiologic Studies Depression Scale. A longitudinal mediation model with a cross-lagged panel model was run. As robust check, the models were applied with a longer follow-up period (from 2012 to 2018). Additionally, results were estimated in China.

RESULTS

Bidirectional associations have been found among the accumulation of chronic conditions, disability, and depressive symptoms, especially between disability and depression. Disability (T2) mediated 11.11 % and 16.87 % of the association between the accumulation of chronic conditions (T1) and depression (T3) for men and women in the United States. The results were consistent in robust analysis.

CONCLUSIONS

This study found that men and women routinely experienced disability and depressive symptoms because of the accumulation of chronic conditions. In terms of depressive symptoms, women were more sensitive to the accumulation of chronic conditions through disability.

Factors affecting cognitive frailty improvement and progression in Taiwanese older adults

BACKGROUND

Knowledge of predictors of cognitive frailty (CF) trajectories is required to develop preventive strategies to delay or reverse the progression from CF to dementia and other adverse outcomes. This 2-year prospective study aimed to investigate factors affecting the progression and improvement of CF in older Taiwanese adults.

METHODS

In total, 832 community-dwelling people aged ≥ 65 years were eligible. Fried's five frailty criteria were used to measure prefrailty and frailty, while cognitive performance was assessed by the Clinical Dementia Rating and Mini-Mental State Examination. Each component of reversible CF and potentially reversible CF was assigned a score, with a total score ranging 0 to 5 points. Two annual follow-up CF assessments were conducted. The group-based trajectory model was applied to identify latent CF trajectory groups, and a multinomial logistic regression was used to examine relationships of explanatory variables with CF trajectories.

RESULTS

According to data on 482 subjects who completed the two annual follow-ups, three CF trajectories of robust, improvement, and progression were identified. After adjusting for the baseline CF state, CF progression was significantly associated with an older age (odds ratio [OR] = 1.08; 95% confidence interval [CI], 1.02 ~ 1.14), a lower Tinetti balance score (OR = 0.72; 95% CI, 0.54 ~ 0.96), a slower gait (OR = 0.98; 95% CI, 0.97 ~ 0.99), and four or more comorbidities (OR = 2.65; 95% CI, 1.19 ~ 5.90), while CF improvement was not significantly associated with any variable except the baseline CF state. In contrast, without adjusting for the baseline CF state, CF progression was significantly associated with an older age, female sex, balance scores, gait velocity, regular exercise, the number of comorbidities, and depression, while CF improvement was significantly associated with female sex, balance scores, and the number of comorbidities.

CONCLUSIONS

The baseline CF state, an older age, poorer balance, slower gait, and a high number of comorbidities may contribute to CF progression, while the baseline CF state may account for associations of engaging in regular exercise and depression with CF development.

Multimorbidity, healthy lifestyle, and the risk of cognitive impairment in Chinese older adults: a longitudinal cohort study

BACKGROUND

Evidence on the association between multimorbidity and cognitive impairment in Chinese older population is limited. In addition, whether a healthy lifestyle can protect cognitive function in multimorbid older population remains unknown.

METHODS

A total of 6116 participants aged ≥ 65 years from the Chinese Longitudinal Healthy Longevity Survey were followed up repeatedly. The number of coexisting chronic diseases was used for assessing multimorbidity and cardiometabolic multimorbidity. Three lifestyle statuses (unhealthy, intermediate, and healthy) were defined based on a lifestyle score covering smoking, alcohol drinking, body mass index, outdoor activities, and dietary pattern. Cognitive impairment was defined as the Mini-Mental State Examination score < 24. A modified Poisson regression model with robust error variance was used to assess the associations between multimorbidity, healthy lifestyle, and cognitive impairment.

RESULTS

During a median follow-up period of 5.8 years, 1621 incident cases of cognitive impairment were identified. The relative risk (RR) of cognitive impairment associated with heavy multimorbidity burden (≥ 3 conditions) was 1.39 (95% confidence interval: 1.22-1.59). This association declined with age, with RRs being 3.08 (1.78-5.31), 1.40 (1.04-1.87), and 1.19 (1.01-1.40) in subjects aged < 70 years, ≥ 70 and < 80 years, and ≥ 80 years, respectively (P for interaction = 0.001). Compared to unhealthy lifestyle, a healthy lifestyle was related to an approximately 40% reduced risk of cognitive impairment regardless of multimorbidity burden. Among the 5 lifestyle factors assessed, daily outdoor activities and a healthy dietary pattern showed convincing protective effects on cognitive function.

CONCLUSIONS

The relationship between multimorbidity and cognitive impairment is age-dependent but remains significant in the population aged 80 years or older. A healthy lifestyle may protect cognitive function regardless of the multimorbidity burden. These findings highlight the importance of targeting individuals with heavy multimorbidity burden and promoting a heathy lifestyle to prevent cognitive impairment in Chinese older population.

Trajectory of multimorbidity before dementia: A 24-year follow-up study

INTRODUCTION

Although the multimorbidity-dementia association has been widely addressed, little is known on the long-term trajectory of multimorbidity (TOM) in preclinical dementia.

METHODS

Based on the Health and Retirement Study, burden of multimorbidity was quantified with the total number of eight long-term conditions (LTC). Patterns of TOM before dementia diagnosis were investigated with mixed-effects models.

RESULTS

In 1752 dementia cases and 5256 matched controls, cases showed higher and faster increasing predicted number of LTC than controls, with a significant case-control difference from 20 years prior to dementia diagnosis. Larger increases in number of LTC during preclinical phase of dementia were found in White participants, females, those whose age at dementia onset was younger, and those who were less educated.

DISCUSSION

Our findings emphasize the faster accumulation of multimorbidity in prodromal dementia than in natural aging, as well as effect modifications by age and sex.

Highlights

TOM increased faster in prodromal dementia than in natural ageing.Patterns of TOM by dementia status diverged at 20 years before dementia diagnosis.Patterns of TOM were modified by age and sex.