Genetic predictors for cardiovascular disease in hispanics

Statin indication according to the 2019 World Health Organization cardiovascular disease risk charts and carotid ultrasound in Mexican mestizo rheumatoid arthritis patients

Background

We aimed to assess the concordance of recommendation for initiating statin therapy according to the 2019 World Health Organization (WHO) cardiovascular disease (CVD) risk charts and to the presence of carotid plaque (CP) identified with carotid ultrasound in Mexican mestizo rheumatoid arthritis (RA) patients, and to determine the proportion of patients reclassified to a high cardiovascular risk after the carotid ultrasound was performed.

Methods

This was a cross-sectional study nested of a RA patients’ cohort. A total of 157 Mexican mestizo RA patients were included. The cardiovascular evaluation was performed using the 2019 WHO CVD risk charts (laboratory-based model) for the Central Latin America region. A carotid ultrasound was performed in all patients. The indication to start statin therapy was considered if the patient was classified as high risk, moderate risk if > 40 years with total cholesterol (TC) > 200 mg/dl or LDL-C > 120 mg/dl, and low risk if > 40 years with TC > 300 mg/dl, according to the WHO CVD risk chart or if the patient had carotid plaque (CP). Cohen’s kappa (k) coefficient was used to evaluate the concordance between statin therapy initiation.

Results

Initiation of statin therapy was considered in 49 (31.2%) patients according to the 2019 WHO CVD risk charts and 49 (31.2%) patients by the presence of CP. Cardiovascular risk reclassification by the presence of CP was observed in 29 (18.9%) patients. A slight agreement (k = 0.140) was observed when comparing statin therapy recommendations between 2019 WHO CVD risk charts and the presence of CP.

Conclusion

The WHO CVD risk charts failed to identify a large proportion of patients with subclinical atherosclerosis detected by the carotid ultrasound and the concordance between both methods was poor. Therefore, carotid ultrasound should be considered in the cardiovascular evaluation of RA patients.

APOE Gene Associated with Cholesterol-Related Traits in the Hispanic Population

Genetic variants in the apolipoprotein E (APOE) gene are associated with lipid metabolism and lipid-related traits in the non-Hispanic population. There have been limited studies regarding the association between the APOE gene and hypercholesterolemia in the Hispanic population; therefore, our aim for this study is to examine the APOE gene’s associations with cholesterol level and its related phenotypes. The APOE gene consists of three different alleles, ε2, ε3, and ε4, with ε4 being associated with dementia and cardiovascular diseases. A total of 1,382 subjects were collected from the Texas Alzheimer’s Research and Care Consortium (TARCC, N = 1320) and the Initial Study of Longevity and Dementia from the Rio Grande Valley (ISLD-RGV, N = 62). Questionnaires on demographics, medical history, and blood/saliva samples were collected and APOE genotypes were performed. We observed allele frequencies of the APOE ε3 (96.7%), ε4 (22.6%) and ε2 (6.8%) alleles, respectively. Multivariable logistic regression revealed a significant association between the APOE ε4 allele and hypercholesteremia (p = 1.8 × 10⁻⁴) in our studied Hispanic population. We prove for the first time, that the APOE ε4 allele increases the risk for hypercholesterol in Hispanics. Further research is needed to confirm and supports our current findings.

Renal Function Decline in Latinos With Type 2 Diabetes

Introduction

Diabetic nephropathy remains a highly prevalent microvascular complication in individuals with type 2 diabetes mellitus (T2DM). Hispanic individuals are at increased risk of metabolic and cardiovascular complications compared with non-Hispanic white individuals. We described the long-term kidney outcomes using a culturally based approach to diabetes management in Hispanic patients implemented by the Joslin Diabetes Center’s Latino Diabetes Initiative.

Methods

Our retrospective study included 594 Hispanic patients evaluated at the Joslin Diabetes Center from July 2002 to July 2015. Demographic and clinical data were collected from the outpatient visits.

Results

Uncontrolled high blood pressure (hazard ratio [HR]: 1.72; 95% confidence interval [CI]:1.18–2.51; P = 0.005), overweight (HR: 2.68; 95% CI: 1.13–6.38; P = 0.026), and longstanding T2DM duration (HR: 1.11; 95% CI: 1.08–1.14; P < 0.0001) at baseline were significantly associated with increased risk of chronic kidney disease (CKD). Although poor glycemic control (HR: 1.18; 95% CI: 1.099–1.258; P < 0.0001), systolic blood pressure (SBP) >140 (HR: 1.01; 95% CI: 1.006–1.02; P = 0.0002), and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use (HR: 1.53; 95% CI: 1.03–2.29; P = 0.04) were significantly associated with increased CKD incidence during follow-up. Interestingly, statin use was associated with lower CKD incidence during the follow-up (HR: 0.52; 95% CI: 0.42–0.65; P < 0.0001). The annual rate of renal function decline in our cohort was estimated to be –1.39 ml/min per 1.73 m².

Conclusion

Renal function decline in Latinos is associated with expected but modifiable variables, such as uncontrolled diabetes, uncontrolled hypertension, and being overweight. However, the annual rate of renal function decline in our cohort was estimated to be comparatively higher than previous reports in Hispanic individuals without T2DM, and the general US population with T2DM, but lower than expected for this high-risk group. We highlight the importance of a culturally based patient-centered therapeutic approach to improve long-term outcomes in Hispanic patients at high risk of CKD.

Evaluation of 71 Coronary Artery Disease Risk Variants in a Multiethnic Cohort

Background

Coronary heart disease (CHD) is the most common cause of death worldwide. Previous studies have identified numerous common CHD susceptibility loci, with the vast majority identified in populations of European ancestry. How well these findings transfer to other racial/ethnic populations remains unclear.

Methods and Results

We examined the generalizability of the associations with 71 known CHD loci in African American, Latino and Japanese men and women in the Multiethnic Cohort (6,035 cases and 11,251 controls). In the combined multiethnic sample, 78% of the loci demonstrated odds ratios that were directionally consistent with those previously reported (p = 2 × 10⁻⁶), with this fraction ranging from 59% in Japanese to 70% in Latinos. The number of nominally significant associations across all susceptibility regions ranged from only 1 in Japanese to 11 in African Americans with the most statistically significant association observed through locus fine-mapping noted for rs3832016 (OR = 1.16, p = 2.5×10⁻⁵) in the SORT1 region on chromosome 1p13. Lastly, we examined the cumulative predictive effect of CHD SNPs across populations with improved power by creating genetic risk scores (GRSs) that summarize an individual’s aggregated exposure to risk variants. We found the GRSs to be significantly associated with risk in African Americans (OR = 1.03 per allele; p = 4.1×10⁻⁵) and Latinos (OR = 1.03; p = 2.2 × 10⁻⁸), but not in Japanese (OR = 1.01; p = 0.11).

Conclusions

While a sizable fraction of the known CHD loci appear to generalize in these populations, larger fine-mapping studies will be needed to localize the functional alleles and better define their contribution to CHD risk in these populations.

Distinct and Shared Determinants of Cardiomyocyte Contractility in Multi-Lineage Competent Ethnically Diverse Human iPSCs

The realization of personalized medicine through human induced pluripotent stem cell (iPSC) technology can be advanced by transcriptomics, epigenomics, and bioinformatics that inform on genetic pathways directing tissue development and function. When possible, population diversity should be included in new studies as resources become available. Previously we derived replicate iPSC lines of African American, Hispanic-Latino and Asian self-designated ethnically diverse (ED) origins with normal karyotype, verified teratoma formation, pluripotency biomarkers, and tri-lineage in vitro commitment. Here we perform bioinformatics of RNA-Seq and ChIP-seq pluripotency data sets for two replicate Asian and Hispanic-Latino ED-iPSC lines that reveal differences in generation of contractile cardiomyocytes but similar and robust differentiation to multiple neural, pancreatic, and smooth muscle cell types. We identify shared and distinct genes and contributing pathways in the replicate ED-iPSC lines to enhance our ability to understand how reprogramming to iPSC impacts genes and pathways contributing to cardiomyocyte contractility potential.

Sugar-sweetened beverage intake, chromosome 9p21 variants, and risk of myocardial infarction in Hispanics

BACKGROUND

Chromosome 9p21 variants are among the most robust genetic markers for coronary artery disease (CAD), and previous studies have suggested that genetic effects of this locus might be modified by dietary factors. Intake of sugar-sweetened beverages (SSBs), which are the main dietary source of added sugar, has been shown to interact with genetic factors in affecting CAD risk factors such as obesity.

OBJECTIVE

We aimed to test whether SSB intake modified the association between chromosome 9p21 variants and CAD risk in Hispanics living in Costa Rica.

DESIGN

The current study included 1560 incident cases of nonfatal myocardial infarction (MI) and 1751 population-based controls. Three independent single nucleotide polymorphisms (SNPs) at the chromosome 9p21 locus were genotyped. SSB intake was assessed with the use of a food-frequency questionnaire and was defined as the frequency of intake of daily servings of sweetened beverages and fruit juice.

RESULTS

We showed a significant interaction between SSB intake and one of the 3 variants (i.e., rs4977574) on MI risk. The per–risk allele OR (95% CI) of rs4977574 for MI was 1.44 (1.19, 1.74) in participants with higher SSB consumption (>2 servings/d), 1.21 (1.00, 1.47) in those with average consumption (1–2 servings/d), and 0.97 (0.81, 1.16) in subjects with lower consumption (<1 serving/d; P-interaction = 0.005). A genetic risk score derived from the sum of risk alleles of the 3 SNPs also showed a significant interaction with SSB intake on MI risk (P-interaction = 0.03).

CONCLUSION

Our data suggest that unhealthy dietary habits such as higher intake of SSBs could exacerbate the effects of chromosome 9p21 variants on CAD.

Type 2 Diabetes Genetic Predisposition, Obesity, and All-Cause Mortality Risk in the U.S.: A Multiethnic Analysis

OBJECTIVE

Type 2 diabetes (T2D) is associated with increased mortality in ethnically diverse populations, although the extent to which this association is genetically determined is unknown. We sought to determine whether T2D-related genetic variants predicted all-cause mortality, even after accounting for BMI, in the Third National Health and Nutrition Examination Survey.

RESEARCH DESIGN AND METHODS

We modeled mortality risk using a genetic risk score (GRS) from a weighted sum of risk alleles at 38 T2D-related single nucleotide polymorphisms. In age-, sex-, and BMI-adjusted logistic regression models, accounting for the complex survey design, we tested the association with mortality in 6,501 participants. We repeated the analysis within ethnicities (2,528 non-Hispanic white [NHW], 1,979 non-Hispanic black [NHB], and 1,994 Mexican American [MA]) and within BMI categories (<25, 25-30, and ≥30 kg/m(2)). Significance was set at P < 0.05.

RESULTS

Over 17 years, 1,556 participants died. GRS was associated with mortality risk (OR 1.04 [95% CI 1.00-1.07] per T2D-associated risk allele, P = 0.05). Within ethnicities, GRS was positively associated with mortality risk in NHW and NHB, but not in MA (0.95 [0.90-1.01], P = 0.07). The negative trend in MA was largely driven by those with BMI <25 kg/m(2) (0.91 [0.82-1.00]). In NHW, the positive association was strongest among those with BMI ≥30 kg/m(2) (1.07 [1.02-1.12]).

CONCLUSIONS

In the U.S., a higher T2D genetic risk was associated with increased mortality risk, especially among obese NHW. The underlying genetic basis for mortality likely involves complex interactions with factors related to ethnicity, T2D, and body weight.

Genome-wide significant loci: how important are they? Systems genetics to understand heritability of coronary artery disease and other common complex disorders

Genome-wide association studies (GWAS) have been extensively used to study common complex diseases such as coronary artery disease (CAD), revealing 153 suggestive CAD loci, of which at least 46 have been validated as having genome-wide significance. However, these loci collectively explain <10% of the genetic variance in CAD. Thus, we must address the key question of what factors constitute the remaining 90% of CAD heritability. We review possible limitations of GWAS, and contextually consider some candidate CAD loci identified by this method. Looking ahead, we propose systems genetics as a complementary approach to unlocking the CAD heritability and etiology. Systems genetics builds network models of relevant molecular processes by combining genetic and genomic datasets to ultimately identify key "drivers" of disease. By leveraging systems-based genetic approaches, we can help reveal the full genetic basis of common complex disorders, enabling novel diagnostic and therapeutic opportunities.

Hispanic Americans living in the United States and their risk for obesity, diabetes and kidney disease: Genetic and environmental considerations

The Hispanic American, the largest minority population in the United States, is at increased risk for obesity, diabetes and end-stage renal disease. Here we review genetic and environmental factors that might account for their increased risk for these conditions. Whereas many environmental and genetic factors have important roles in driving the increased risk for obesity and kidney disease in this population, a case is made that excessive intake of sugary beverages is a contributory cause. Studies focusing on decreasing intake of sugary beverages among the Hispanic American could potentially reduce renal and cardiovascular complications in this population.