Diverse Life Experiences Study Research Articles

Association of Social Integration with Cognitive Status in a Multi-Ethnic Cohort: Results From the Kaiser Healthy Aging and Diverse Life Experiences Study.

We evaluated overall and race-specific relationships between social integration and cognition in older adults. Kaiser Healthy Aging and Diverse Life Experiences (KHANDLE) cohort participants included 1343 Asian, Black, Latino, or non-Latino White Kaiser Permanente Northern California members. We estimated the effect of social integration on verbal episodic memory, semantic memory, and executive function derived from the Spanish and English Neuropsychological Assessment (SENAS) Scales. Social integration scores included marital status; volunteer activity; and contact with children, relatives, friends, and confidants. We estimated covariate-adjusted linear mixed-effects models for baseline and 17-month follow-up cognition. Social integration was associated with higher baseline cognitive scores (average = 0.066 (95% confidence interval: 0.040, 0.092)) overall and in each racial/ethnic group. The association did not vary by race/ethnicity. Social integration was not associated with the estimated rate of cognitive change. In this cohort, more social integration was similarly associated with better late-life cognition across racial/ethnic groups.

Perceived Discrimination, Nativity, and Cognitive Performance in a Multiethnic Study of Older Adults: Findings From the Kaiser Healthy Aging and Diverse Life Experiences Study.

Despite growing research on the association between discrimination and disparities in cognitive aging, an evidence gap remains on how the association varies by racial/ethnic group. This study evaluates the associations of experiences of discrimination with cognitive function and whether these associations varied by race/ethnicity and nativity. Using the Kaiser Healthy Aging and Diverse Life Experiences (KHANDLE) cohort (N = 1 712) with approximately equal groups of Black, White, Latino, and Asian community-dwelling older adults aged 65 years and older, we evaluated the associations between self-reported experiences of everyday and major lifetime discrimination with overall cognitive performance and domain-specific cognition (verbal episodic memory, semantic memory, and executive functioning) across race/ethnicity and nativity. Linear regression models examined the cross-sectional association between self-reported experiences of everyday and major lifetime discrimination with z-standardized coefficients for cognition. We tested for effect modification by race and nativity. All models controlled for age, sex, and education. Among KHANDLE participants (mean age: 76 years; SD: 6.8), everyday discrimination was not associated with cognitive scores. Major lifetime discrimination was associated with better average cognitive scores among Black participants but not among other racial/ethnic groups. Major lifetime discrimination was associated with better average cognitive scores among U.S.-born but not among non-U.S.-born individuals. Our findings do not imply that discrimination improves cognition, but rather suggest that future research should include more detailed measures on discrimination and unfair treatment that could help disentangle the extent to which relationships are causal or reflect some other underlying factor.

Sex differences in the association between education in adulthood and late‐life cognition in the Kaiser Health Aging and Diverse Life Experiences (KHANDLE) Study

AbstractBackgroundWhile education is strongly associated with late‐life cognitive level, it is unclear how education after young adulthood is associated with late‐life cognition. This study examines the association between adult education and overall and domain specific cognition in a diverse sample allowing for possible differences in associations by sex. This is important to consider given recent increases in educational opportunities for women.MethodThe Kaiser Healthy Aging and Diverse Life Experiences Study (KHANDLE) enrolled Kaiser Permanente Northern California members age 65+ who completed a Multiphasic Health Checkup (MHC) conducted from 1964‐1996. Among 1,363 KHANDLE participants who reported education attainment at an MHC before age 25, education in adulthood was a binary variable reflecting reporting higher levels of education during KHANDLE interviews than at their first MHC visit after age 25. Executive function, semantic memory and verbal episodic memory were captured through the Spanish and English Neuropsychological Assessment Scales (SENAS) during KHANDLE baseline interviews and z‐standardized. Linear regressions estimated the association between education in adulthood and domain‐specific late‐life cognition adjusting for age at MHC, age at KHANDLE, sex, race/ethnicity, and educational attainment at MHC. Stratified models and interaction terms tested for possible sex differences in associations.ResultWomen were more likely than men to have ≤ HS at their MCH (33% vs 20%; chi‐square p‐value=<0.0001) and to receive additional education during adulthood (37% vs 27%; chi‐square p‐value=<0.0001). Among recipients of adult education, 50% had ≤ HS at their MCH and at the KHANDLE interview 25% completed HS or trade school, 18% completed college, and 24% completed graduate school. Education during adulthood was associated with executive function (β=0.18, 95% CI: 0.07, 0.28) but not semantic memory (β=0.09, 95% CI: ‐0.02, 0.19) nor verbal episodic memory (β=0.06, 95% CI: ‐0.05, 0.18). The association between adulthood education and executive function was stronger among women than men (women: β=0.19, 95% CI: 0.06, 0.32; men β=0.12, 95% CI: ‐0.07, 0.32; executive function*female interaction term p‐value=0.04).ConclusionEducation during adulthood was associated with better executive function among women. Additional research is needed to assess if education during adulthood is associated with cognition and cognitive decline in late‐life.

Nativity differences in lifecourse socioeconomic position and late‐life cognition among KHANDLE participants

AbstractBackgroundSocioeconomic position (SEP) in childhood and adulthood is associated with late‐life cognition. Less is known about how SEP changes may be associated with late‐life cognition in diverse cohorts.MethodsThe Kaiser Healthy Aging and Diverse Life Experiences Study (KHANDLE) is a cohort of community‐dwelling Kaiser Permanente members who reside in the San Francisco Bay area and Sacramento valley (n=1,708; Asians (24%), Blacks (26%), Latinos (20%) and Whites (30%)). KHANDLE aims to evaluate how lifecourse and sociocultural factors influence late‐life brain health and cognitive decline and contribute to race/ethnic disparities. We used linear regression to test the association between lifecourse SEP trajectories and late‐life cognition and tested if these associations differed by US vs. foreign nativity. Childhood SEP is a composite of parents’ education (≥HS vs. <HS), childhood hunger, and self‐reported family financial status. Adult SEP included participants’ education (≥HS vs. <HS), late‐life low income status (e.g. qualified for low‐income welfare programs), and self‐reported social status. Participants were classified as having consistently high SEP (HH), low childhood/high adult SEP (LH), high childhood/low adult SEP (HL), or consistently low SEP (LL). Executive function, semantic memory and verbal episodic memory measured with the Spanish and English Neuropsychological Assessment Scales (SENAS) were z‐standardized and averaged for overall cognition. Pooled analyses adjusted for age, race/ethnicity, gender, and foreign nativity.ResultsOverall, participants classified as LH did not differ from HH (ref.) in any cognitive domain, while those classified as HL and LL had lower cognition than HH in all domains (see table). We observed a significant interaction of US vs. foreign birth and lifecourse SES trajectory for semantic memory (p=0.01), but no other domain. Stratified analyses demonstrated a similar pattern to pooled. However, foreign‐born participants HL participants had significantly lower overall cognition (p=0.03), and verbal memory (p=0.02) than US‐born HL participants. By contrast, foreign‐born LH participants performed significantly better than US‐born LH in semantic memory (p=0.01).ConclusionsThose with high Adult SEP had the best cognitive function, regardless of childhood SEP or nativity. In some measures of cognition, foreign‐born HL participants performed worse than US‐born, while foreign‐born LH performed better.

Early adulthood and midlife cardiovascular risk factors and late‐life cognition in KHANDLE: A lifecourse study of a diverse cohort

AbstractBackgroundMidlife cardiovascular risks (CVR) are associated with late‐life cognition and dementia. Prior studies that examine early and midlife CVR on cognitive aging in Asians, Blacks, and Latinos are limited.MethodsThe Kaiser Healthy Aging and Diverse Life Experiences Study (KHANDLE) is a cohort of community‐dwelling Kaiser Permanente members residing in Northern California (Asians (26%), Blacks (29%), Latinos (20%) and Whites (24%)) who completed a multiphasic health checkup (MHC) from 1977‐1985 (n=1,207; mean age=37.6). KHANDLE aims to evaluate how lifecourse factors influence late‐life brain health and cognitive decline and may impact race/ethnic disparities. Using linear regression, we examined the association between late‐life cognition and early/midlife hypertension, hyperlipidemia and overweight/obesity collected at MHC. Executive function, semantic memory and verbal episodic memory measured using the Spanish and English Neuropsychological Assessment Scales (SENAS) were z‐standardized and combined for a composite measure of overall cognition. We tested for effect modification by race/ethnicity. Models controlled for age at KHANDLE, age at MHC, gender, and education.ResultsAt KHANDLE baseline, mean age was 75.4(6.7). At MHC, 46% of participants were ages 26‐35, 47% ages 36‐49 and 7% ages 50‐65. Prevalence of 2+ CVR was highest in Blacks (24%), followed by Latinos (24%), Asians (15%), and Whites (13%). Across race/ethnicity, having 2+ risk factors was associated with lower cognition in all domains: Overall cognition β=‐0.35 (‐0.47, ‐0.23). Having hypertension, hyperlipidemia or being overweight/obese was associated with worse cognition in all race/ethnic groups and across all cognitive domains (see table). Effect estimates varied by race/ethnicity, but interactions were not statistically significant: Blacks with hypertension (n=108) had lower late‐life cognition than other groups, especially for semantic memory and verbal episodic memory; Latinos with hyperlipidemia (n=49) had worse verbal memory than other groups; whites who were overweight/obese (n=84) had lower late‐life cognition across all domains, while Asians who were overweight/obese (n=50) had better late‐life cognition than non‐Asian participants who were overweight/obese.ConclusionsEarly/midlife cardiovascular risk factors are associated with lower late‐life cognition in all race/ethnic groups. The association between specific cardiovascular risk factors and late‐life cognition may vary by race/ethnicity, but differences were not significant.

Do the Benefits of Educational Attainment for Late-life Cognition Differ by Racial/Ethnic Group?: Evidence for Heterogenous Treatment Effects in the Kaiser Healthy Aging and Diverse Life Experience (KHANDLE) Study.

Educational attainment is associated with late-life cognitive performance and dementia; few studies have examined diverse racial/ethnic groups to assess whether the association differs by race/ethnicity. We investigated whether the association between educational attainment and cognition differed between White, Black, Asian, and Latino participants in the Kaiser Healthy Aging and Diverse Life Experiences study (n=1348). Covariate-adjusted multivariable linear regression models examined domains of verbal episodic memory, semantic memory, and executive functioning. We observed significant effect heterogeneity by race/ethnicity only for verbal episodic memory (P=0.0198), for which any schooling between high school and college was beneficial for White, Asian, and Black participants, but not Latino participants. We found no evidence of heterogeneity for semantic memory or executive function. With the exception of Latino performance on verbal episodic memory, more education consistently predicted better cognitive scores to a similar extent across racial/ethnic groups, despite likely heterogenous educational and social experiences.