Epigenome-wide association study of lung function in Latino children and youth with asthma

Introduction DNA methylation studies have associated methylation levels at different CpG sites or genomic regions with lung function. Moreover, genetic ancestry has been associated with lung function in Latinos. However, no epigenome-wide association study (EWAS) of lung function has been performed in this population. Here, we aimed to identify DNA methylation patterns associated with lung function in pediatric asthma among Latinos. Results We conducted an EWAS in whole blood from 250 Puerto Rican and 148 Mexican American children and young adults with asthma. A total of five CpGs exceeded the genome-wide significance threshold of p = 1.17 × 10−7 in the combined analyses from Puerto Ricans and Mexican Americans: cg06035600 (MAP3K6, p = 6.13 × 10−8) showed significant association with pre-bronchodilator Tiffeneau–Pinelli index, the probes cg00914963 (TBC1D16, p = 1.04 × 10−7), cg16405908 (MRGPRE, p = 2.05 × 10−8), and cg07428101 (MUC2, p = 5.02 × 10−9) were associated with post-bronchodilator forced vital capacity (FVC), and cg20515679 (KCNJ6) with post-bronchodilator Tiffeneau–Pinelli index (p = 1.13 × 10−8). However, these markers did not show significant associations in publicly available data from Europeans (p > 0.05). A methylation quantitative trait loci analysis revealed that methylation levels at these CpG sites were regulated by genetic variation in Latinos and the Biobank-based Integrative Omics Studies (BIOS) consortium. Additionally, two differentially methylated regions in REXOC and AURKC were associated with pre-bronchodilator Tiffeneau–Pinelli index (adjusted p < 0.05) in Puerto Ricans and Mexican Americans. Moreover, we replicated some of the previous differentially methylated signals associated with lung function in non-Latino populations. Conclusions We replicated previous associations of epigenetic markers with lung function in whole blood and identified novel population-specific associations shared among Latino subgroups.

Healthcare utilization and costs among high-need and frail Mexican American Medicare beneficiaries

Objectives To examine Medicare health care spending and health services utilization among high-need population segments in older Mexican Americans, and to examine the association of frailty on health care spending and utilization. Methods Retrospective cohort study of the innovative linkage of Medicare data with the Hispanic Established Populations for the Epidemiologic Study of the Elderly (H-EPESE) were used. There were 863 participants, which contributed 1,629 person years of information. Frailty, cognition, and social risk factors were identified from the H-EPESE, and chronic conditions were identified from the Medicare file. The Cost and Use file was used to calculate four categories of Medicare spending on: hospital services, physician services, post-acute care services, and other services. Generalized estimating equations (GEE) with a log link gamma distribution and first order autoregressive, correlation matrix was used to estimate cost ratios (CR) of population segments, and GEE with a logit link binomial distribution was applied to estimate odds ratios (OR) of healthcare use. Results Participants in the major complex chronic illness segment who were also pre-frail or frail had higher total costs and utilization compared to the healthy segment. The CR for total Medicare spending was 3.05 (95% CI, 2.48–3.75). Similarly, this group had higher odds of being classified in the high-cost category 5.86 (95% CI, 3.35–10.25), nursing home care utilization 11.32 (95% CI, 3.88–33.02), hospitalizations 4.12 (95% CI, 2.88–5.90) and emergency room admissions 4.24 (95% CI, 3.04–5.91). Discussion Our findings highlight that frailty assessment is an important consideration when identifying high-need and high-cost patients.

Walking Engagement in Mexican Americans Who Participated in a Community-Wide Step Challenge in El Paso, TX

In the United States, the Latinx population has the highest prevalence of physical inactivity compared with other ethnicities. Research shows that work-based physical activity interventions have been widely implemented in the non-Latinx population and effectively increase physical activity in the non-Latinx population. In an effort to improve physical activity and reduce obesity among the Latinx population, we conducted 10,000 Steps for 100 Days, an employer-based walking challenge campaign, to increase walking engagement among Latinx employees located in El Paso, Texas. Participants reported their number of steps using a pedometer or smartphone. Step counts were collected at baseline, 2 weeks post challenge, and 6 months post challenge. Screenshots of the tracking device were uploaded to an online tracker. Regression analysis was conducted to identify covariates associated with baseline and 2-week and 6-month average daily steps. Generalized estimating equations (GEE) were performed to predict steps over time by demographic characteristics. Participation in the 10,000 Steps for 100 Days walking challenge was associated with a sustained increase in average daily steps. Participants with less than 7000 steps per day demonstrated the greatest increase in average daily steps (921 steps at 2 weeks; 1002.4 steps at 6 months). Demographic characteristics were not significant predictors of average steps, except that married participants had higher average steps. Participants with 10,000 or more daily steps had a 51% (p = 0.031) higher chance of having a professional occupation than a non-professional one compared to those with 7000 or fewer daily steps. We provided initial evidence that the walking challenge is an effective approach for improving physical activity in the Latinx population.

Sex-Specific Differences in the Association Between Race/Ethnicity and NAFLD Among US Population

Non-alcoholic fatty liver disease (NAFLD) is spreading worldwide, with a racial/ethnic disparity. We examined the gender role in the racial/ethnic difference in NAFLD in the US population. We analyzed data for 3,292 individuals ≥18 years old from NHANES 2017–2018, a representative sample of the non-institutionalized adult population in the US. Exclusions were subjects with elevated transferrin level, chronic hepatitis B or C, excessive alcohol use, or prescription medications that might cause hepatic steatosis. NAFLD was diagnosed by FibroScan® using controlled attenuation parameter (CAP) values: S0 &lt;238, S1 = 238–259, S2 = 260–290, S3 &gt;290. Data were analyzed using Chi square and multinomial regression. The overall prevalence of NAFLD was 47.9% [S2 = 16.1%, and S3 = 31.8%]. The prevalence of S3 was highest among Mexican Americans (46%), lowest among Blacks (22.7%), 29.9% in other Hispanics and 32.1% in Whites (p &lt; 0.05). It was higher among Mexican American males (54.1%) compared to Mexican American females (37.7%) (p &lt; 0.05). In the adjusted model, Mexican Americans were two times more likely than Whites to have S2 and S3 (p &lt; 0.05). Only male Mexican Americans had higher odds of S2 and S3 relative to male White (p &lt; 0.05). Males had higher odds of S3 relative to non-menopausal females (p &lt; 0.05). There was no difference in the odds of S2 or S3 NAFLD among the menopausal females with or without hormone therapy relative to non-menopausal females (p &gt; 0.05). While Mexican Americans had the highest prevalence of severe NAFLD relative to the other racial/ethnic groups, only male Mexican Americans, but not females, had higher likelihood of both moderate and severe NAFLD relative to Whites. Interventions that specifically target Mexican American males are needed to increase awareness about NAFLD and its prevention.

Body Mass Index and Frailty Among Older Mexican Americans: Findings From an 18-year of Follow-up

The objective of this study was to examine body mass index (BMI) as predictor of frailty among non-frail Mexican American older adults at baseline. Data are from an 18-year prospective cohort of 1,647 non-institutionalized Mexican American aged ≥ 67 years from the Hispanic Established Population for the Epidemiologic Study of the Elderly (1995/1996-2012/13). BMI (Kg/m2) was grouped according to the National Institutes of Health obesity standards (&lt;18.5=underweight, 18.5–24.9=normal weight, 25.0–29.9=overweight, 30.0–34.9=obesity category I and ≥ 35=obesity category II and extreme obesity). Frailty was defined as meeting three or more of the following: unintentional weight loss of &gt;10 pounds, weakness, self-reported exhaustion, low physical activity, and slow walking speed. Covariates included socio-demographics, comorbidities, cognitive function, depressive symptoms, and limitations in activities of daily living (ADL). General Estimating Equations were performed to estimate the odds ratio (OR) and 95% confidence interval (CI) of frailty as a function of BMI categories. All variables were analyzed as time varying except for gender and education. Participants in the underweight or obesity type II / morbidity obesity category had increased OR of frailty over time than those in the normal weight category (2.68, 95% CI=1.46-4.9 vs.1.55, 95% CI=1.02-2.35, respectively) after controlling for all covariates. Those who reported arthritis, hip fracture, depressive symptoms, or ADL disability had increased odds of frailty over time. This study showed a U-shaped relationship between BMI and frailty over an 18-year period of follow-up which has implications for maintaining a healthy weight to prevent frailty in this population.

Documentation of Dementia as a Cause of Death Among Mexican-American Decedents With Dementia

There is lack of data on the frequency and correlates of dementia being documented as a cause of death in Hispanic populations. We investigated characteristics associated with dementia as a cause of death among Mexican-American decedents diagnosed with dementia. Data came from the Hispanic Established Populations for the Epidemiologic Study of the Elderly, Medicare claims files, and the National Death Index. Of the 744 decedents diagnosed with dementia before death, 26.9% had dementia documented as a cause of death. More health comorbidities (OR=0.38, 95% CI=0.25-0.57), older age at death (OR=1.05, 95% CI=1.01-1.08), and longer dementia duration (OR=1.09, 95% CI=1.03-1.16) were associated with dementia as a cause of death. In the last year of life, any ER admission with (OR=0.56, 95% CI=0.32-0.98) or without (OR=0.31, 95% CI=0.14-0.70) a hospitalization, more physician visits (OR=0.95, 95% CI=0.92-0.98) and seeing a medical specialist (OR=0.41, 95% CI=0.24-0.70) were associated with lower odds for dementia as a cause of death. In the last 30-days of life, any hospitalization with an ICU stay (OR=0.57, 95% CI=0.37-0.88) and ER admission with (OR=0.58, 95% CI=0.40-0.84) or without (OR=0.48, 95% CI=0.25-0.94) a hospitalization were associated with lower odds for dementia as a cause of death. Receiving hospice care in the last 30-days of life was associated with 2.09 (95% CI=1.38-3.16) higher odds for dementia as a cause of death. The possible under-documentation of dementia as a cause of death on death certificates may result in underestimation of healthcare resource need of dementia care for Mexican-Americans.

Physical Function Transitions and Healthcare Utilization Among Older Mexican Americans

The aim of this study was to examine the relationship between 2-year physical function transitions and one-year healthcare utilization among Mexican American Medicare beneficiaries. The sample consisted of 429 Mexican Americans ≥75 years old from the Hispanic Established Population for the Epidemiologic Study of the Elderly linked with Medicare claims data from the Centers for Medicare and Medicaid Services. Short Physical Performance Battery (SPPB) from Wave 5 (2004/05) to Wave 6 was used to create physical function transition groups. The outcomes were physician visits (&lt;6, 6-12, &gt;12 visits), number of emergency room visits, and number of acute hospitalizations one-year after physical function transitions. Multinomial logistic regression and Generalized Estimating Equation with negative binomial distribution were used to estimate the odds ratio of healthcare utilization as a function of physical function transition groups, controlling for socio-demographics and comorbidities. Participants who improved or remained moderate-high physical function had lower odds ratio (OR) of being hospitalized (0.40, 95% Confidence Interval [CI]=(0.18, 0.90)) or visiting the emergency room (OR=0.52, 95% CI=0.32-0.84) one-year later compared to participants who remained in the low physical function group. No difference in physician visits across physical function transition groups was found. This study showed healthcare utilization differed by physical function transition groups among Mexican American Medicare beneficiaries. Physical function improvement or maintenance of moderate-high physical function should be targeted in older Mexican Americans, a population at great risk of developing disability, to reduce or delay dependency and healthcare burden.

The Role of Obesity in Frailty Incidence: The San Antonio Longitudinal Study of Aging

Background Although initially conceptualized as a wasting syndrome, obesity has been associated with frailty in prior studies. The goal of this study was to examine the associations of obesity and waist circumference with frailty and determine whether they predict incident frailty in an ethnically diverse population of older Mexican Americans (MAs) and European Americans (EAs). Methods 749 MA and EA community-dwelling older adults (65+) participated in the baseline examination of the San Antonio Longitudinal Study of Aging (SALSA), and 474 participants completed the first follow up approximately 6 years later. Frailty was classified using Fried criteria. Baseline characteristics, including body mass index (BMI) and waist circumference (WC) were summarized by frailty category (non-frail, pre-frail, frail) using ANOVA. The odds of becoming frail at follow-up by baseline BMI and WC were estimated using separate logistic regression models, adjusting for age, sex, ethnicity, diabetes, comorbidity (presence of ≥2 chronic diseases not including diabetes), baseline frailty score, and follow-up time. Results At baseline, participants were 69 ±3 years old, 61% female, and 50% MA. BMI and WC increased with increasing frailty category (p &lt;0.01 for both). BMI was a significant predictor of incident frailty (OR=1.08, 95% confidence interval [CI]: 1.02-1.14, p=0.011). WC also predicted frailty (OR=1.03, 95% CI: 1.01-1.05, p =0.017). Conclusion These results demonstrate that BMI and WC are significant predictors of frailty. Interventions which target obesity may reduce the incidence of frailty; however, more research in this area is needed.