Dementia remains the major predictor of death among octogenarians. A study of two population cohorts of 85-year-olds examined 22 years apart

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.

Prevalence of benign paroxysmal positional vertigo in a population-based setting among 75-year-olds

BACKGROUND

Benign paroxysmal positional vertigo (BPPV) is one of the most frequently diagnosed cause of dizziness among older adults.

OBJECTIVE

To investigate the prevalence of BPPV and positional symptoms of dizziness and nystagmus among 75-year-olds and to identify factors associated with BPPV and positional dizziness and nystagmus.

METHODS

In this cross-sectional population-based study of 75-78-year-olds in Gothenburg, 887 participants were examined with questions regarding dizziness and health and social factors. A total of 681 participants underwent the Dix-Hallpike test or the side-lying test for BPPV using Video Frenzel goggles.

RESULTS

In total 32% reported problems with dizziness (n = 887). The prevalence of BPPV was 4% in the unweighted and 4.5% in the weighted analyses, compensating for selective attrition of women and participants with previous positional dizziness. Positional dizziness without nystagmus was found in 2% and nystagmus without dizziness was found in 9%. Individuals with BPPV and positional dizziness experienced more dizziness in everyday life compared with those with normal tests, while those with positional nystagmus did not.

CONCLUSIONS

The estimated prevalence of BPPV among 75-year-olds was 4.5%. Despite weighted analyses, the true prevalence may be higher since many participants with dizziness refused testing. Dizziness was associated with fear and discomfort so strong that around 20% of the participants declined testing.

What Matters and What Matters Most for Survival After age 80? A Multidisciplinary Exploration Based on Twin Data

Given research and public interest for conditions related to an extended lifespan, we addressed the questions of what matters and what matters most for subsequent survival past age 80. The data was drawn from the population-based and multidisciplinary Swedish OCTO Twin Study, in which a sample (N = 699) consisting of identical and same-sex fraternal twin pairs, followed from age 80 until death, provided detailed data on health, physical functioning, life style, personality, and sociodemographic conditions. Information concerning date of birth and death were obtained from population census register. We estimated heritability using an ACE model and evaluated the role of multiple predictors for the mortality-related hazard rate using Cox regression. Our findings confirmed a low heritability of 12%. As expected, longer survival was associated with being a female, an apolipoprotein E (APOE) e4 allele non-carrier, and a non-smoker. Several diseases were found to be associated with shorter survival (cerebrovascular, dementia, Parkinson's, and diabetes) as well as certain health conditions (high diastolic blood pressure, low body mass index, and hip fracture). Stronger grip and better lung function, as well as better vision (but not hearing), and better cognitive function (self-evaluated and measured) was related to longer survival. Social embeddedness, better self-evaluated health, and life-satisfaction were also significantly associated with longer survival. After controlling for the impact of comorbidity, functional markers, and personality-related predictors, we found that sex, cerebrovascular diseases, compromised cognitive functioning, self-related health, and life-satisfaction remained as strong predictors. Cancer was only associated with the mortality hazard when accounting for other co-morbidities. The survival estimates were mostly in anticipated directions and contained effect sizes within the expected range. Noteworthy, we found that some of the so-called "soft-markers" remained strong predictors, despite a control for other factors. For example, self-evaluation of health and ratings of life-satisfaction provide additional and valuable information.