Depression and memory function - evidence from cross-lagged panel models with unit fixed effects in ELSA and HRS

Prevalence and risk factors of cognitive frailty among pre-frail and frail older adults in nursing homes

BACKGROUND

The purpose of this research was to stratify the level of frailty to examine the risk factors associated with reversible cognitive frailty (RCF) and potentially reversible cognitive frailty (PRCF) in nursing homes to provide a basis for hierarchical management in different stages of frailty.

METHODS

The study was a cross-sectional study conducted from September to November 2022; 504 people were selected by stratified random sampling after convenience selection from the Home for the Aged Guangzhou. The structured questionnaire survey was conducted through face-to-face interviews using the general data questionnaire, Fried Frailty Phenotype, Montreal Cognitive Assessment Scale.

RESULTS

In total, 452 individuals were included for analysis. A total of 229 cases (50.7%) were PRCF, 70 (15.5%) were RCF. Multivariate logistic regression analysis showed that in pre-frailty, the Geriatric Depression Scale (GDS-15) score (odds ratio (OR) 1.802; 95% CI 1.308-2.483), Instrumental Activities of Daily Living Scale (IADL) score (0.352; 0.135-0.918) and energy (0.288; 0.110-0.755) were influencing factors of RCF. GDS-15 score (1.805; 1.320-2.468), IADL score (0.268; 0.105-0.682), energy (0.377; 0.150-0.947), lack of intellectual activity (6.118; 1.067-35.070), admission time(>3 years) (9.969; 1.893-52.495) and low education (3.465; 1.211-9.912) were influencing factors of PRCF. However, RCF with frailty was associated with the Short-Form Mini-Nutritional Assessment (MNA-SF) score (0.301; 0.123-0.739) and low education time (0 ~ 12 years) (0.021; 0.001-0.826). PRCF with frailty was associated with age (1.327; 1.081-1.629) and weekly exercise time (0.987; 0.979-0.995).

CONCLUSIONS

The prevalence of RCF and PRCF was high among pre-frail and frail older adults in nursing homes. Different levels of frailty had different influencing factors for RCF and PRCF. Depression, daily living ability, energy, intellectual activity, admission time, education level, nutrition status, age and exercise time were associated with RCF and PRCF. Hierarchical management and intervention should be implemented for different stages of frailty to prevent or delay the progression of cognitive frailty.

Harmonization of Later-Life Cognitive Function Across National Contexts: Results from the Harmonized Cognitive Assessment Protocols (HCAPs)

Background

The Harmonized Cognitive Assessment Protocol (HCAP) is an innovative instrument for cross-national comparisons of later-life cognitive function, yet its suitability across diverse populations is unknown. We aimed to harmonize general and domain-specific cognitive scores from HCAPs across six countries, and evaluate precision and criterion validity of the resulting harmonized scores.

Methods

We statistically harmonized general and domain-specific cognitive function across the six publicly available HCAP partner studies in the United States, England, India, Mexico, China, and South Africa (N=21,141). We used an item banking approach that leveraged common cognitive test items across studies and tests that were unique to studies, as identified by a multidisciplinary expert panel. We generated harmonized factor scores for general and domain- specific cognitive function using serially estimated graded-response item response theory (IRT) models. We evaluated precision of the factor scores using test information plots and criterion validity using age, gender, and educational attainment.

Findings

IRT models of cognitive function in each country fit well. We compared measurement reliability of the harmonized general cognitive function factor across each cohort using test information plots; marginal reliability was high (r> 0·90) for 93% of respondents across six countries. In each country, general cognitive function scores were lower with older ages and higher with greater levels of educational attainment.

Interpretation

We statistically harmonized cognitive function measures across six large, population-based studies of cognitive aging in the US, England, India, Mexico, China, and South Africa. Precision of the estimated scores was excellent. This work provides a foundation for international networks of researchers to make stronger inferences and direct comparisons of cross-national associations of risk factors for cognitive outcomes.

Funding

National Institute on Aging (R01 AG070953, R01 AG030153, R01 AG051125, U01 AG058499; U24 AG065182; R01AG051158).

Relationship between Cognition, Depression, and Oral health status in Older adults: A longitudinal cross-lagged analysis

BACKGROUND

The world's population is aging increasingly, and older adults' physical and mental health needs to be prioritized. Although several studies have explored the relationship between cognition, depression, and oral health in older adults, the exact nature and direction of this relationship are poorly understood. Moreover, most studies to date have been cross-sectional, with fewer longitudinal studies. The current longitudinal study explored the relationship between cognition, depression, and oral health in older adults.

METHODS

We used data from two waves (2018, 2020) of the Korean Longitudinal Study of Aging, which included 4543 older adults aged 60 years and older. General socio-demographic characteristics were analyzed using descriptive analysis, and study variables were described using t-tests. Generalized Estimating Equations (GEE) and cross-lagged models were used to examine the longitudinal associations between cognition, depression, and oral health.

RESULTS

The GEE results suggested that better cognition and less depression over time were associated with better oral health in older adults. Cross-lagged models further validated the effect of depression on oral health over time.

LIMITATIONS

The directionality of the influence of cognition on oral health could not be determined.

CONCLUSIONS

Although there were several limitations, our study provided novel ideas for verifying the effects of cognition and depression on oral health in older adults.

Pathways linking abdominal obesity to poor memory function: Explore the mediating role of hypertension and depressive symptoms

BACKGROUND

The negative effect of abdominal obesity on cognitive function has been widely reported, especially on memory function, however, it is unclear how the effect is mediated. We aim to investigate the mediating role of hypertension and depressive symptoms.

METHODS

Data were collected from wave 6 (2012-2013) of the English Longitudinal Study of Ageing (ELSA). Abdominal obesity was defined as a waist circumference (WC) ≥88cm for women and ≥102cm for men. Hypertension was determined on the basis of objective blood pressure measurement and previous physician diagnosis. Depressive symptoms were assessed with the 8-item version of the Center for Epidemiologic Studies (CESD) scale. Memory function was measured with the 10-word immediate and delayed recall tests. Baron and Kenny's causal steps and Karlson/Holm/Breen (KHB) method were used to examine the mediating effect.

RESULTS

A total of 7,448 participants aged ≥50 years were included in this study. We found a negative effect of abdominal obesity on memory function (β=-0.047, p=0.031). KHB method identified significant mediating effect of hypertension and depressive symptoms on the relationship between abdominal obesity and memory function, they explained 16.92 and 6.32% of the total effect of abdominal obesity on memory function, respectively.

LIMITATIONS

This study was limited by its cross-sectional design and possibility of residual confounding.

CONCLUSIONS

Hypertension and depressive symptoms might be possible pathways linking abdominal obesity and poor memory function, suggesting that collaborative interventions of abdominal obesity, hypertension and depressive symptoms are beneficial in maintaining memory function.