Secular changes in late-life cognition and well-being: Towards a long bright future with a short brisk ending?

Sex differences in the association of physical function and cognitive function with life satisfaction in older age: The Rancho Bernardo Study

OBJECTIVES

This study examines the cross-sectional associations of cognitive and physical function with life satisfaction in middle-class, community-dwelling adults aged 60 and older.

STUDY DESIGN

Participants were 632 women and 410 men who had cognitive function tests (CFT) and physical function tasks (PFT) assessed at a clinic visit between 1988 and 1992, and who responded in 1992 to a mailed survey that included life satisfaction measures. Cognitive impairment was defined as ≤24 on MMSE, ≥132 on Trails B, ≤12 on Category Fluency, ≤13 on Buschke long-term recall, and ≤7 on Heaton immediate recall. Physical impairment was defined as participants' self-reported difficulty (yes/no) in performing 10 physical functions. Multiple linear regression examined associations between life satisfaction and impairment on ≥1 CFT or difficulty with ≥1 PFT.

MAIN OUTCOME MEASURES

The Satisfaction with Life Scale (SWLS; range:0-26) and Life Satisfaction Index-Z (LSI-Z; range:5-35).

RESULTS

Participants' average age was 73.4 years (range=60-94). Categorically defined cognitive impairment was present in 40% of men and 47% of women. Additionally, 30% of men and 43% of women reported difficulty performing any PFT. Adjusting for age and impairment on ≥1 CFT, difficulty performing ≥1 PFT was associated with lower LSI-Z and SWLS scores in men (β=-1.73, -1.26, respectively, p<0.05) and women (β=-1.79, -1.93, respectively, p<0.01). However, impairment on ≥ 1 CFT was not associated with LSI-Z or SWLS score after adjusting for age and difficulty with ≥1 PFT.

CONCLUSIONS

Limited cognitive function was more common than limited physical function; however, limited physical function was more predictive of lower life satisfaction. Interventions to increase or maintain mobility among older adults may improve overall life satisfaction.

Cohort Differences in Psychosocial Function over 20 Years: Current Older Adults Feel Less Lonely and Less Dependent on External Circumstances

BACKGROUND

Lifespan psychological and life course sociological perspectives indicate that individual development is shaped by social and historical circumstances. Increases in fluid cognitive performance over the last century are well documented and researchers have begun examining historical trends in personality and subjective well-being in old age. Relatively less is known about secular changes in other key components of psychosocial function among older adults.

OBJECTIVE

In the present study, we examined cohort differences in key components of psychosocial function, including subjective age, control beliefs, and perceived social integration, as indicated by loneliness and availability of very close others.

METHODS

We compared data obtained 20 years apart in the Berlin Aging Study (in 1990-1993) and the Berlin Aging Study II (in 2013-2014) and identified case-matched cohort groups based on age, gender, cohort-normed education, and marital or partner status (n = 153 in each cohort, mean age = 75 years). In follow-up analyses, we controlled for having lived in former East versus West Germany, physical diseases, cohort-normed household income, cognitive performance, and the presence of a religious affiliation.

RESULTS

Consistently across analyses, we found that, relative to the earlier-born BASE cohort (year of birth: mean = 1916; SD = 3.38 years; range = 1901-1922), participants in the BASE-II sample (year of birth: mean = 1939; SD = 3.22 years; range = 1925-1949) reported lower levels of external control beliefs (d = -1.01) and loneliness (d = -0.63). Cohorts did not differ in subjective age, availability of very close others, and internal control beliefs.

CONCLUSION

Taken together, our findings suggest that some aspects of psychosocial function of older adults have improved across the two recent decades. We discuss the possible role of sociocultural factors that might have led to the observed set of cohort differences.

Editorial

Human aging is characterized by large differences between and within older adults. Numerous factors are known to contribute to these differences, including genetic and immunological, somatic and medical, cognitive and behavioral, psychosocial and experiential, as well as socioeconomic and geospatial conditions. Continuing and expanding the scientific objectives of the Berlin Aging Study, the Berlin Aging Study II (BASE-II) seeks to comprehensively describe phenomena associated with aging and old age and to better understand the multiple different underlying factors and their interactions. To this end, BASE-II was established as a multi-institutional project combining and integrating interdisciplinary perspectives ranging from molecular genetics and immunology, geriatric medicine and psychology, to sociology and economics. In this Special Issue, we have compiled seven empirical analyses that feature examples of interdisciplinary insights that BASE-II provides by linking data across multiple levels of analyses at which human functioning and development occur in old age. Here, we provide an overview of the study, note commonalities between BASE-II and earlier studies, and highlight some of its unique qualities.

Sports and Exercise at Different Ages and Leukocyte Telomere Length in Later Life--Data from the Berlin Aging Study II (BASE-II)

Physical activity and sports have repeatedly been reported to be associated with telomere length. We studied the association of different types of sports across different stages of life on relative leukocyte telomere length (rLTL) in advanced age.815 participants (397 men) from the Berlin Aging Study II aged over 61 years were included in the analysis. rLTL was measured by real time PCR and physical activity was determined retrospectively by questionnaire, assessing type and duration of sports in the past as well as currently. Five separate multiple linear regression models adjusted for various control variables were performed. 67.3% of participants exercised currently, whereas 19.4% performed sports only between the age of 20 and 30. rLTL was higher in subjects who stated to exercise currently (N = 456), and in subjects who engaged in endurance (N = 138) or intensive activity sports (N = 32). Current physical activity was positively associated with rLTL in the risk factor adjusted regression model (β = 0.26, p < 0.001) and practicing sports for a minimum of 10 years preceding the assessment had a significant effect on rLTL (β = 0.39, p = 0.011). The highest impact was seen for intensive activity sports (β = 0.79, p < 0.001) and physical activity since at least 42 years (β = 0.47, p = 0.001). However, physical activity only between 20 and 30 years of age did not affect rLTL in old age when compared to no sports at all (β = -0.16, p = 0.21). Physical activity is clearly associated with longer rLTL. The effect is seen with longer periods of physical activity (at least 10 years), with intensive sports activities having the greatest impact on rLTL. Our data suggest that regular physical activity for at least 10 years is necessary to achieve a sustained effect on rLTL.

Historical improvements in well-being do not hold in late life: Birth- and death-year cohorts in the United States and Germany

One key objective of life span research is to examine how individual development is shaped by the historical time people live in. Secular trends favoring later-born cohorts on fluid cognitive abilities have been widely documented, but findings are mixed for well-being. It remains an open question whether secular increases in well-being seen in earlier phases of life also manifest in the last years of life. To examine this possibility, we made use of longitudinal data obtained from the mid-1980s until the late 2000s in 2 large national samples in the United States (Health and Retirement Study [HRS]) and Germany (German Socio-Economic Panel [SOEP]). We operationally defined historical time from 2 complementary perspectives: birth-year cohorts based on the years in which people were born (earlier: 1930s vs. later: 1940s) and death-year cohorts based on the years in which people died (earlier: 1990s vs. later: 2000s). To control for relevant covariates, we used case-matched groups based on age (at death) and education and covaried for gender, health, and number of observations. Results from both countries revealed that well-being in old age was indeed developing at higher levels among later-born cohorts. However, for later-deceased cohorts, no evidence for secular increases in well-being was found. To the contrary, later-dying SOEP participants reported lower levels of well-being at age 75 and 2 years prior to death and experienced steeper late-life declines. Our results suggest that secular increases in well-being observed in old age do not manifest in late life, where "manufactured" survival may be exacerbating age- and mortality-related declines.