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.

Cholesterol alone or in combination is associated with frailty among community-dwelling older adults: A cross-sectional study.

BACKGROUND: Biological markers contribute to the precise intervention across the continuum of frailty severity. Few studies have explored the advantages of biological markers collected as part of primary care data among community-dwelling older adult population and controversy remains regarding the classic biological markers for frailty. METHODS: We recruited a total of 8791 adults with a mean age of 71.95 years who met the inclusion and exclusion criteria in Guancheng District and Dalang Town, Dongguan, China. Frailty was assessed by a Chinese frailty evaluation scale. Frailty status was classified with 33-item modified frailty index and latent class analysis was applied to explore the latent classes (subtypes) of frailty. We measured biological markers on blood samples collected. We identify association between specific biological markers or patterns and frailty by logistic regression and association rule mining (ARM) based on the Apriori algorithm. RESULTS: Multivariable analysis of our data showed that an elevated white blood cell (WBC) count and high cholesterol (CHOL) level were associated with pre-frailty (adjusted odds ratio [aOR] = 1.231, 95 % confidence interval [CI] = 1.009-1.501; aOR = 0.703, 95 % CI = 0.623-0.793) and frailty (aOR = 1.500, 95 % CI = 1.130-1.993; aOR = 0.561, 95 % CI = 0.461-0.684) compared with the normal groups. Importantly, significantly high level of CHOL was associated with a lower risk of four frailty subtypes compared with relatively healthy participants with the most power of association in the multi-frail group (aOR = 0.182, 95 % CI = 0.086-0.386). Based on ARM technique to develop correlation analysis to identify important high-risk clusters among older adult transitions from non-frail to frailty, patterns for normal level of CHOL co-occurred with an elevated creatinine (CREA) level have a significant association with the risk of frailty (aOR = 7.787, 95 % CI = 1.978-30.648) after adjusting for targeted confounders. CONCLUSIONS: Our study highlights the correlation between classic biological markers, especially CHOL and frailty status and subtypes among community-dwelling older adult, in the primary care setting. Further large-scale prospective studies are still needed to confirm the role of classic biological markers in frailty.