Adherence to High Dietary Diversity and Incident Cognitive Impairment for the Oldest-Old: A Community-Based, Nationwide Cohort Study

BACKGROUND AND AIMS

Dietary diversity change is associated with cognitive function, however, whether the effect still exists among the oldest-old (80+) is unclear. Our aim was to examine the effect of dietary diversity changes on cognitive impairment for the oldest-old in a large prospective cohort.

METHODS

Within the Chinese Longitudinal Healthy Longevity Study, 6237 adults older than 80 years were included. The dietary diversity score (DDS) was assessed by a simplified food frequency questionnaire (FFQ). Cognitive impairment was defined as a Mini-Mental State Examination (MMSE) score lower than 18 points. Cognitive decline was defined as a reduction of total MMSE score ≥3 points, and cognitive decline of different subdomains was defined as a reduction of ≥15% in the corresponding cognitive domain. The multivariate-adjusted Cox proportional hazard model evaluated the effects of DDS change on cognitive decline. The linear mixed-effect model was used to test subsequent changes in MMSE over the years.

RESULTS

During 32,813 person-years of follow-up, 1829 participants developed cognitive impairment. Relative to the high-high DDS change pattern, participants in the low-low and high-low patterns were associated with an increased risk of cognitive impairment with a hazard ratio (95% confidential interval, CI) of 1.43 (1.25, 1.63) and 1.44 (1.24, 1.67), and a faster decline in the MMSE score over the follow-up year. Participants with the low-high pattern had a similar incidence of cognitive impairment with HRs (95% CI) of 1.03 (0.88, 1.20). Compared with the stable DDS status group (-1-1), the risk of cognitive impairment was higher for those with large declines in DDS (≤-5) and the HR was 1.70 (95% CI: 1.44, 2.01).

CONCLUSIONS

Even for people older than 80, dietary diversity change is a simple method to identify those who had a high risk of cognitive decline. Keeping high dietary diversity is beneficial for cognitive function and its subdomain even in the final phase of life, especially for females and the illiterate oldest-old.

Relationships between socio-clinico-demographic factors and global cognitive function in the oldest old living in the Tokyo Metropolitan area: Reanalysis of the Tokyo Oldest Old Survey on Total Health (TOOTH)

BACKGROUND

Despite a steady increase in life expectancy, a few studies have investigated cross-sectional correlates and longitudinal predictors of cognitive function, a core domain of the successful aging, among socio-clinico-demographic factors in the oldest-old exclusively.

OBJECTIVES

The aims of this study were to examine socio-clinico-demographic characteristics associated with global cognition and its changes in the oldest-old.

METHODS

We reanalyzed a dataset of cognitively preserved community-dwelling subjects aged 85 years and older in the Tokyo Oldest Old Survey on Total Health, a 6-year longitudinal observational study. This study consisted of (1) baseline cross-sectional analyses examining correlates of global cognition (n = 248) among socio-clinico-demographic factors and (2) longitudinal analyses examining baseline predictors for changes of global cognition in 3-year follow-up (n = 195). The Mini-Mental State Examination was used as a screening test to assess global cognition.

RESULTS

At baseline, higher weights were related to higher cognitive function in the oldest-old. The baseline predictors of global cognitive decline in 3-year follow-up were higher global cognition, shorter education period, and lower sociocultural activities and lower instrumental activity of daily living, in this order.

CONCLUSIONS

The present study suggests that it is crucial to attain higher education during early life and avoid leanness or obesity, participate in sociocultural cognitive activities during late life, and maintain instrumental activity of daily living to preserve optimal cognitive function in the oldest-old, which will facilitate developing prevention strategies for cognitive decline and promoting successful aging in this increasing population.

Association of circulating branched-chain amino acids with cardiometabolic traits differs between adults and the oldest-old

Branched-chain amino acids (BCAAs) are promising for their potential anti-aging effects. However, findings in adults suggest that circulating BCAAs are associated with cardiometabolic risk. Moreover, little information is available about how BCAAs influence clustered cardiometabolic traits in the oldest-old (>85 years), which are the fastest-growing segment of the population in developed countries. Here, we applied a targeted metabolomics approach to measure serum BCAAs in Chinese participants (aged 21-110 years) based on a longevity cohort. The differences of quantitative and dichotomous cardiometabolic traits were compared across BCAAs tertiles. A generalized additive model (GAM) was used to explore the dose-response relationship between BCAAs and the risk of metabolic syndrome (MetS). Overall, BCAAs were correlated with most of the examined cardiometabolic traits. The odds ratios for MetS across the increasing BCAA tertiles were 3.22 (1.70 - 6.12) and 5.27 (2.88 - 9.94, referenced to tertile 1) after adjusting for age and gender (P_trend < 0.001). The association still existed after further controlling for lifestyle factors and inflammation factors. However, the correlations between circulating BCAAs and quantitative traits were weakened in the oldest-old, except for lipids, the levels of which were distinctly different from those in adults. The stratified analysis also suggested that the risky BCAAs-MetS association was more pronounced in adults than in the oldest-old. Moreover, generalized additive model (GAM)-based curve-fitting suggested that only when BCAAs exceeded a threshold (approximately 450 μmol/L) was the BCAAs-MetS association significant. The relationship might be aging-dependent and was more pronounced in adults than in the oldest-old.

Relationship Between Ties With Adult Children and Life Satisfaction Among the Middle-Aged, the Young-Old, and the Oldest-Old Korean Adults

One of the important determinants of well-being among aging parents is their relationship with adult children. Using the two waves of the Korean Longitudinal Study of Ageing, this study examined how different types of ties with adult children affect the life satisfaction of the Korean middle-aged, the young-old, and the oldest-old adults. Multigroup analysis was used to see if the effects of ties with adult children differ by the three age-groups. The results showed that frequency of contact had positive effect on life satisfaction for all of the age-groups. However, coresidence with children had a negative effect for the middle-aged, but a positive effect for the oldest-old. Finally, exchanges of support with adult children had significant effects only for the young-old. These results show that the importance of different types of ties with children change according to aging parents' life stages.

Predictors of mortality in men and women aged 90 and older: a nine-year follow-up study in the Vitality 90+ study

BACKGROUND

information about the predictors of mortality among the oldest-old is limited. Also possible gender differences are poorly known.

OBJECTIVE

to examine the predictors of mortality among individuals aged 90 and older, focusing on differences between men and women. We also analysed gender differences in survival at different levels of mobility and activities in daily living (ADL).

DESIGN

this 9-year follow-up study is part of the Vitality 90+ study, a population-based study of people aged 90 and older.

SUBJECTS

all inhabitants aged 90 and older in the area of Tampere, Finland were contacted, irrespective of health or dwelling place. The study population consisted of 171 men and 717 women.

METHODS

data were collected with a mailed questionnaire asking questions concerning ADL and mobility, self-rated health, chronic conditions and socio-economic factors. The participation rate was 79%. Cox regression enter models were used for the analysis.

RESULTS

older age, male gender, disability in ADL and mobility, poor self-rated health and institutionalisation increased the risk of mortality in the total study group. In age-adjusted Cox regression models, ADL and mobility were stronger predictors in men than in women (gender interactions, P < 0.001). Among those who were partly but not totally dependent in ADL or mobility women survived longer than men.

CONCLUSION

the same health indicators that are important at younger old age also predict mortality in the oldest-old. Disability increases the likelihood of death more in men than women. At a very old age, women survive longer with moderate disability than do men.