Childhood and Life-Course Socioeconomic Position and Cognitive Function in the Adult Population of the Hispanic Community Health Study/Study of Latinos.

The Hispanic/Latino population experiences socioeconomic adversities across the lifespan and is at greater risk of cognitive impairment, yet little is known about the role of life-course socioeconomic position (SEP) in cognitive function in this population. Using baseline data (2008-2011) from adults (aged 45-74 years) of the Hispanic Community Health Study/Study of Latinos, we assessed the association between childhood SEP and socioeconomic mobility with cognitive function, and whether this association was mediated by midlife SEP. Childhood SEP was assessed using parental education. An index combining participants' education and household income represented midlife SEP. Socioeconomic mobility was categorized as stable low, downward or upward mobility, and stable high-SEP. Cognitive function measures were modeled using survey linear regression with inverse-probability weighting, accounting for covariates. We used mediation analysis to estimate the indirect effect of childhood SEP on cognition through midlife SEP. High childhood SEP was associated with global cognition in adulthood (coefficient for parental education beyond high school vs. less than high school = 0.26, 95% confidence interval: 0.15, 0.37). This association was partially mediated through midlife SEP (indirect effect coefficient = 0.16, 95% confidence interval: 0.15, 0.18). Low SEP through the life course was associated with the lowest cognitive function. This study provides evidence that life-course SEP influences cognitive performance in adulthood.

Beyond borders: A commentary on the benefit of promoting immigrant populations in genome-wide association studies.

Immigrants are an important part of many high-income nations, in that they contribute to the sociocultural tapestry, economic well-being, and demographic diversity of their receiving countries and communities. Yet, genomic studies to date have generally focused on non-immigrant, European-ancestry populations. Although this approach has proven fruitful in discovering and validating genomic loci, within the context of racially/ethnically diverse countries like the United States-wherein half of immigrants hail from Latin America and another quarter from Asia-this approach is insufficient. There is a persistent diversity gap in genomic research in terms of both current samples and genome-wide association studies, meaning that the field's understanding of genetic architecture and gene-environmental interactions is being hampered. In this commentary, I provide motivating examples of recent research developments related to the following: (1) how the increased ancestral diversity, such as seen among Latin American immigrants, improves power to discover and document genomic loci, (2) informs how environmental factors, such as immigration-related exposures, interact with genotypes to influence phenotypes, and (3) how inclusion can be promoted through community-engaged research programs and policies. I conclude that greater inclusion of immigrants in genomic research can move the field forward toward novel discoveries and interventions to address racial/ethnic health disparities.

Demographic and sociocultural risk factors for adulthood weight gain in Hispanic/Latinos: results from the Hispanic Community Health Study / Study of Latinos (HCHS/SOL).

BACKGROUND: United States (US) Hispanic/Latinos experience a disproportionate burden of obesity, which may in part be related to demographic or sociocultural factors, including acculturation to an US diet or inactive lifestyle. Therefore, we sought to describe the association between adulthood weight histories and demographic and sociocultural factors in a large diverse community-based cohort of US Hispanic/Latinos. METHODS: We estimated the effect of several factors on weight gain across adulthood, using multivariable linear mixed models to leverage 38,759 self-reported current body weights and weight histories recalled for 21, 45 and 65 years of age, from 15,203 adults at least 21 years of age at the baseline visit of the Hispanic Community Health Study/Study of Latinos (2008-2011). RESULTS: The average rate of weight gain was nearly 10 kg per decade in early adulthood, but slowed to < 5 kg a decade among individuals 60+ years of age. Birth cohort, gender, nativity or age at immigration, Hispanic/Latino background, and study site each significantly modified the form of the predicted adulthood weight trajectory. Among immigrants, weight gain during the 5 years post-migration was on average 0.88 kg (95% CI: 0.04, 1.72) greater than the weight gain during the 5 years prior. The rate of weight gain appeared to slow after 15 years post-migration. CONCLUSIONS: Using self-reported and weight history data in a diverse sample of US Hispanic/Latinos, we revealed that both demographic and sociocultural factors were associated with the patterning of adulthood weight gain in this sample. Given the steep rate of weight gain in this population and the fact that many Hispanic/Latinos living in the US immigrated as adults, efforts to promote weight maintenance across the life course, including after immigration, should be a top priority for promoting Hispanic/Latino health and addressing US health disparities more broadly.

Genetic analyses of diverse populations improves discovery for complex traits.

Genome-wide association studies (GWAS) have laid the foundation for investigations into the biology of complex traits, drug development and clinical guidelines. However, the majority of discovery efforts are based on data from populations of European ancestry1-3. In light of the differential genetic architecture that is known to exist between populations, bias in representation can exacerbate existing disease and healthcare disparities. Critical variants may be missed if they have a low frequency or are completely absent in European populations, especially as the field shifts its attention towards rare variants, which are more likely to be population-specific4-10. Additionally, effect sizes and their derived risk prediction scores derived in one population may not accurately extrapolate to other populations11,12. Here we demonstrate the value of diverse, multi-ethnic participants in large-scale genomic studies. The Population Architecture using Genomics and Epidemiology (PAGE) study conducted a GWAS of 26 clinical and behavioural phenotypes in 49,839 non-European individuals. Using strategies tailored for analysis of multi-ethnic and admixed populations, we describe a framework for analysing diverse populations, identify 27 novel loci and 38 secondary signals at known loci, as well as replicate 1,444 GWAS catalogue associations across these traits. Our data show evidence of effect-size heterogeneity across ancestries for published GWAS associations, substantial benefits for fine-mapping using diverse cohorts and insights into clinical implications. In the United States-where minority populations have a disproportionately higher burden of chronic conditions13-the lack of representation of diverse populations in genetic research will result in inequitable access to precision medicine for those with the highest burden of disease. We strongly advocate for continued, large genome-wide efforts in diverse populations to maximize genetic discovery and reduce health disparities.

Assessing function and endurance in adults with spinal and bulbar muscular atrophy: validity of the adult myopathy assessment tool.

Purpose. The adult myopathy assessment tool (AMAT) is a performance-based battery comprised of functional and endurance subscales that can be completed in approximately 30 minutes without the use of specialized equipment. The purpose of this study was to determine the construct validity and internal consistency of the AMAT with a sample of adults with spinal and bulbar muscular atrophy (SBMA). Methods. AMAT validity was assessed in 56-male participants with genetically confirmed SBMA (mean age, 53 ± 10 years). The participants completed the AMAT and assessments for disease status, strength, and functional status. Results. Lower AMAT scores were associated with longer disease duration (r = -0.29; P < 0.03) and lower serum androgen levels (r = 0.49-0.59; P < 0.001). The AMAT was significantly correlated with strength and functional status (r = 0.82-0.88; P < 0.001). The domains of the AMAT exhibited good internal consistency (Cronbach's α = 0.77-0.89; P < 0.001). Conclusions. The AMAT is a standardized, performance-based tool that may be used to assess functional limitations and muscle endurance. The AMAT has good internal consistency, and the construct validity of the AMAT is supported by its significant associations with hormonal, strength, and functional characteristics of adults with SBMA. This trial is registered with Clinicaltrials.gov identifier NCT00303446.