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

Change in Healthy Lifestyle and Subsequent Risk of Cognitive Impairment Among Chinese Older Adults: A National Community-Based Cohort Study

BACKGROUND

The association between change in lifestyle and cognitive impairment remains uncertain.

OBJECTIVES

To investigate the association of change in lifestyle with cognitive impairment.

METHODS

In this study, 4 938 participants aged 65 or older were involved from the Chinese Longitudinal Healthy Longevity Survey for years 2008-2018. A weighted healthy lifestyle score was derived from 4 lifestyle factors (smoking, alcohol consumption, physical activity, and diet). Multivariable Cox proportional hazards regression models were applied to investigate the associations between 3-year changes in healthy lifestyle (2008-2011) and cognitive impairment (2011-2018).

RESULTS

Researchers documented 833 new-onset of cognitive impairments more than 20 097 person-years of follow up. Compared with those in the persistently unhealthy group, those in the improved and persistently healthy groups had a lower risk of cognitive impairment, with the multivariate-adjusted hazard ratios (HRs) of 0.67 (95% confidence interval (CI): 0.55, 0.83) and 0.53 (95% CI: 0.40, 0.71), respectively. Furthermore, a significant interaction was observed between change in lifestyle and sex (p-interaction = .032); the HRs were 0.48 (95% CI, 0.34, 0.69) for the improved group and 0.41 (95% CI: 0.26, 0.64) for persistently healthy group among male vs 0.81 (95% CI, 0.63, 1.04) and 0.64 (95% CI, 0.44, 0.92) among female, respectively.

CONCLUSIONS

This study suggests that improving or maintaining a healthy lifestyle can significantly mitigate the risk of cognitive impairment in Chinese older adults. Additionally, researcher's findings emphasize the significance of maintaining a healthy lifestyle and highlights the potential positive impact of improving previous unhealthy habits, especially for older women.

Cognitive Function, Healthy Lifestyle, and All-Cause Mortality among Chinese Older Adults: A Longitudinal Prospective Study

BACKGROUND

Both cognitive decline and unhealthy lifestyles have been linked to an elevated risk of mortality in older people. We aimed to investigate whether a healthy lifestyle might modify the association between cognitive function and all-cause mortality in Chinese older populations.

METHODS

The final analysis included 5124 individuals free of dementia, selected from the Chinese Longitudinal Healthy Longevity Survey from 2011 to 2018. Cognitive function was assessed in 2011 using the Mini-Mental State Examination (MMSE). A lifestyle score was calculated based on five lifestyle factors, including smoking, alcohol consumption, physical activity, diet, and body mass index. Cox proportional hazards models were performed to evaluate the association between baseline cognitive function and the risk of all-cause mortality, with an interaction term of cognitive function and lifestyle score being added to the models.

RESULTS

The average age of participants was 81.87 years old at baseline. During a median follow-up of 6.4 years, 1461 deaths were documented. Both higher cognitive function (HR: 0.96; 95% CI: 0.96-0.97) and a healthier lifestyle (HR: 0.92; 95% CI: 0.87-0.97) were significantly associated with a reduced risk of mortality. We found that lifestyle significantly modified the association of cognitive function with mortality (p for interaction = 0.004). The inverse relation between cognitive function and mortality was found to be more pronounced among participants with a healthier lifestyle. Of note, among the lifestyle scores component, diet showed a significant interaction with mortality (p for interaction = 0.003), and the protective HR of the all-cause mortality associated with higher MMSE scores was more prominent among participants with healthy diets compared with unhealthy diets.

CONCLUSIONS

Our study indicates that cognitive decline is associated with a higher risk of mortality, and such associations are attenuated by maintaining a healthy lifestyle, with a particular emphasis on healthy diet.

Dietary Diversity and Mild Cognitive Impairment in Middle-Aged and Older Chinese People: A Cross-Sectional Study

Background

The evidence concerning dietary diversity and cognitive function remains insufficient.

Objective

To investigate the association of dietary diversity score (DDS) with mild cognitive impairment (MCI) and cognitive performance in different domains.

Methods

Data from The Lifestyle and Healthy Aging of Chinese Square Dancer Study was used in this study. DDS was constructed based on the intake frequencies of 9 food groups assessed by a validated food frequency questionnaire. MCI was diagnosed by Petersen's criteria. A neuropsychological test battery was used to assess the performance on cognitive domains, and test scores were standardized to Z scores. Multiple linear regression models and logistic regression models were used to estimate the β and odds ratios and their 95% CIs, respectively.

Results

Among 1,982 participants, the mean (SD) age was 63.37 (5.00) years, 1,778 (89.71%) were women, and 279 (14.08%) had MCI. Compared to the DDS quartile (0, 6], the multivariable-adjusted odds ratios (95% CI) were 0.74 (0.48, 1.15) for DDS quartile (6, 7], 0.65 (0.43, 0.97) for DDS quartile (7, 8], and 0.55 (0.37, 0.84) for DDS quartile (8, 9]. Furthermore, higher DDS was positively associated with better performance of cognitive domains, including global cognitive function (β= 0.20, 95% CI: 0.12, 0.30), episodic memory (β= 0.21, 95% CI: 0.07, 0.35), attention (β= 0.15, 95% CI: 0.03, 0.26), language fluency (β= 0.24, 95% CI: 0.10, 0.38), and executive function (β= - 0.24, 95% CI: - 0.38, - 0.10).

Conclusions

This study indicated that higher DDS was associated with better cognitive function among middle-aged and older Chinese people.