Hyperlipidemia in racial/ethnic minorities: differences in lipid profiles and the impact of statin therapy

Challenging Aspects to Precise Health Strategies in Native Hawaiian and Other Pacific Islanders Using Statins

Cardiometabolic disorders (CD), including cardiovascular disease (CVD), diabetes, and obesity, are the leading cause of health concern in the United States (U.S.), disproportionately affecting indigenous populations such a Native Hawaiian and Other Pacific Islanders (NHOPI). Dyslipidemia, a prevalent risk factor for the development and progression of CVD, is more prone to occur in NHOPI than other populations in the U.S. High-intensity statin therapy to reduce low-density lipoprotein cholesterol is associated with the prevention of CVD events. However, significant side-effects, such as muscle disorders, have been associated with its use. Different ethnic groups could experience variation in the prevalence of statin side effects due to sociodemographic, behavioral, and/or biological factors. Therefore, identifying the most impactful determinants that can be modified to prevent or reduce statin side effects for individuals from high-risk ethnic minority groups, such as NHOPI, can lead to more effective strategies to reduce health disparities. Thus, our Mini-Review explores the challenging aspects of public health precise strategies in NHOPI taking statins, including a culturally informed additional therapy that could positively impact the NHOPI population.

Factors associated with hypertriglyceridemia among the hill tribe people aged 30 years and over, Thailand: a cross-sectional study

BACKGROUND

Triglycerides are lipids in the human body that are produced from the consumption of daily food and drink. However, elevated serum triglycerides, also known as hypertriglyceridemia (HTG), are key biomarkers indicating an unhealthy status and increased risks of cardiovascular diseases (CVDs) and pancreatitis. Different groups of people have different patterns and styles of cooking and different patterns of consumption, such as hill tribe people, who have their own unique culture and cooking practices. This study aimed to estimate the prevalence of and determine the factors associated with HTG among the hill tribe population in Thailand.

METHOD

A cross-sectional study was performed. Data and a-5 mL blood sample were collected from participants who were members of one of the six main hill tribes in Thailand: Akah, Lahu, Hmong, Yao, Karen, and Lisu. People who lived in 30 selected hill tribe villages and aged 30 years over were asked to participate the study. Pearson correlation and logistic regression were used to detect the correlations and determine the associations between variables, respectively, at a significant level of α = 0.05.

RESULTS

A total of 2552 participants participated this study; 65.9% were females, 72.35% were aged 40-69 years, 76.7% had no education, 48.7% worked in the agricultural section, and 71.2% had an annual income of less than 50,000 baht/family. Regarding the triglyceride level, 41.7% of participants had elevated levels of serum triglyceride or HTG; 16.4% had a borderline high level, and 25.3% had a high level. After controlling for all potential confounder factors, three variables were found to be associated with elevated serum triglycerides. Those who were members of the Lahu and Hmong tribes were 1.62 times (95%CI = 1.25-2.01) and 1.63 times (95%CI = 1.23-2.16) more likely to have elevated serum triglycerides than those who were members of the Akha tribe, respectively. Those who used a high quantity of cooking oil for daily cooking were 0.73 times less likely to have an abnormal level of triglycerides than those who used a low quantity of cooking oil for daily cooking (95%CI = 0.58-0.91), and those who had a waist circumference indicating obesity were 1.28 times more likely to have an abnormal level of triglycerides than those who had a normal waist circumference (95%CI = 1.08-1.52).

CONCLUSION

Public health programs that focus on encouraging people to have regular exercise to reduce their body weight, particularly in some tribes, such as Lahu and Hmong, should be implemented.

Racial Differences in Prevalence of Cardiometabolic Morbidities Among Homeless Men

INTRODUCTION

Homelessness is associated with an increased risk of cardiometabolic morbidities. However, few studies have been performed to evaluate the racial differences on these morbidities commonly seen in the homeless.

METHODS

A retrospective chart review was conducted to examine the racial differences in the prevalence of cardiometabolic morbidities among the homeless men served at a local health care screening clinic. Medical information was extracted and collated into a single Excel spreadsheet. Racial differences in cardiometabolic morbidities were evaluated using multivariable binary or ordinal logistic regression analyses, adjusting for age, body mass index, and smoking status.

RESULTS

Of the 551 homeless men, 377 (68.4%) were Black, and 174 (31.6%) were White. The mean age (47.8±11.9 years) of Black homeless men was significantly older than that (45.4±13.0 years) of White homeless men (p=0.03). Blacks were 2.7 (95% CI = 1.75, 4.16) times more likely to be in the less desirable HbA1c categories than Whites. By contrast, Blacks were less likely to have non-desirable lipid profile than Whites. Blacks were 0.42 (95% CI = 0.29, 0.62) times and 0.51 (95% CI = 0.28, 0.94) times likely to be in the non-desirable high-density lipoprotein (HDL) and low-density lipoprotein (LDL) categories than Whites, respectively.

CONCLUSION

Black homeless men are more likely to have pre-diabetes or diabetes than White counterparts. On the other hand, Black homeless men have better lipid profiles of HDL or LDL than their White counterparts. Our findings reveal the health challenges of the homeless men and can provide guidance on policy changes related to diet and nutrition of meal programs provided by homeless shelters and congregate meal program to address the health disparities by race in this population.

An evaluation of lipid profile and pro-inflammatory cytokines as determinants of cardiovascular disease in those with diabetes: a study on a Mexican American cohort

Sedentary life styles coupled with high-calorie diets and unhealthy social habits such as smoking, have put an ever-increasing number of people at risk of cardiovascular disorders (CVD), worldwide. A concomitant increase in the prevalence of type 2-diabetes (hyperglycemia), a risk factor for CVD, has further contributed towards escalating CVD-related mortalities. The increase in number of cases of type 2-diabetes underscores the importance of early diagnosis of cardiovascular disease in those with diabetes. In this work, we have evaluated the sensitivity and specificity of dyslipidemia and proinflammatory cytokines to be used as biomarkers for predicting the risk of CVD in those with diabetes. We hypothesize that interplay between dyslipidemia and diabetes-induced low-grade inflammation in those with type 2-diabetes increases the risk of CVD. A total of 215 participants were randomly recruited from the Cameron County Hispanic Cohort (CCHC). Of these, 99% were Mexican Americans living on Texas-Mexico border. Levels of cytokines, adipokines and lipid profile were measured. Cardiovascular disease (CVD) for this study was defined as prior diagnosis of heart attack, angina and stroke, while diabetes was defined by fasting blood glucose (FBG) of > 100 mg/dL and HbA1c of > 6.5, in accordance with American Diabetes Association (ADA) guidelines. Depending on type and distribution of data, various statistical tests were performed. Our results demonstrated higher rates of heart attack (14% vs 11.8%) and stroke (19.8% vs 10%) in those with diabetes as compared to non-diabetes. The odds of having a heart attack were eight times higher in the presence of elevated triglycerides and pro-inflammatory markers (TNFα and IL6) as compared to presence of pro-inflammatory markers only. The odds for heart attack among those with diabetes, increased by 20 fold in presence of high levels of triglycerides, TNFα, and IL6 when coupled with low levels of high-density lipid cholesterol (HDL-C). Lastly, our analysis showed that poorly controlled diabetes, characterized by HbA1c values of > 6.5 increases the odds of stroke by more than three fold. The study quantifies the role of lipid profile and pro-inflammatory markers in combination with standard risk factors towards predicting the risk of CVD in those with type 2-diabetes. The findings from the study can be directly translated for use in early diagnosis of heart disease and guiding interventions leading to a reduction in CVD-associated mortality in those with type 2-diabetes.

Allostatic Load Biomarker Associations with Depressive Symptoms Vary among US Black and White Women and Men

The prevalence and severity of depression differ in women and men and across racial groups. Psychosocial factors such as chronic stress have been proposed as contributors, but causes of this variation are not fully understood. Allostatic load, a measure of the physiological burden of chronic stress, is known to be associated with depression. Using data from the National Health and Nutrition Examination Survey 2005–2010, we examined the associations of nine allostatic load biomarkers with depression among US black and white adults aged 18–64 years (n = 6431). Depressive symptoms were assessed using the Patient Health Questionaire-9; logistic models estimated adjusted odds of depression based on allostatic load biomarkers. High-risk levels of c-reactive protein were significantly associated with increased odds of depression among white women (adjusted odds ratio (aOR) = 1.7, 95% CI: 1.1–2.5) and men (aOR = 1.8, 95% CI: 1.1–2.8) but not black women (aOR = 0.8, 95% CI: 0.6–1.1) or men (aOR = 0.9, 95% CI: 0.5–1.5). Among black men, hypertension (aOR = 1.7, 95% CI: 1.1–2.7) and adverse serum albumin levels (aOR = 1.7, 95% CI: 1.0–2.9) predicted depression, while high total cholesterol was associated with depression among black women (aOR = 1.6, 95% CI: 1.0–2.7). The associations between allostatic load biomarkers and depression varies with gendered race, suggesting that, despite consistent symptomatology, underlying disease mechanisms may differ between these groups.

A method to account for covariate-specific treatment effects when estimating biomarker associations in the presence of endogenous medication use

In the modern era, cardiovascular biomarkers are often measured in the presence of medication use, such that the observed biomarker value for the treated participants is different than their underlying natural history value. However, for certain predictors (e.g. age, gender, and genetic exposures) the observed biomarker value is not of primary interest. Rather, we are interested in estimating the association between these predictors and the natural history of the biomarker that would have occurred in the absence of treatment. Nonrandom medication use obscures our ability to estimate this association in cross-sectional observational data. Structural equation methodology (e.g. the treatment effects model), while historically used to estimate treatment effects, has been previously shown to be a reasonable way to correct endogeneity bias when estimating natural biomarker associations. However, the assumption that the effects of medication use on the biomarker are uniform across participants on medication is generally not thought to be reasonable. We derive an extension of the treatment effects model to accommodate effect modification. Based on several simulation studies and an application to data from the Multi-Ethnic Study of Atherosclerosis, we show that our extension substantially improves bias in estimating associations of interest, particularly when effect modifiers are associated with the biomarker or with medication use, without a meaningful cost of efficiency.

Cost-effectiveness of the non-laboratory based Framingham algorithm in primary prevention of cardiovascular disease: A simulated analysis of a cohort of African American adults

The non-lab Framingham algorithm, which substitute body mass index for lipids in the laboratory based (lab-based) Framingham algorithm, has been validated among African Americans (AAs). However, its cost-effectiveness and economic tradeoffs have not been evaluated. This study examines the incremental cost-effectiveness ratio (ICER) of two cardiovascular disease (CVD) prevention programs guided by the non-lab versus lab-based Framingham algorithm. We simulated the World Health Organization CVD prevention guidelines on a cohort of 2690 AA participants in the Atherosclerosis Risk in Communities (ARIC) cohort. Costs were estimated using Medicare fee schedules (diagnostic tests, drugs & visits), Bureau of Labor Statistics (RN wages), and estimates for managing incident CVD events. Outcomes were assumed to be true positive cases detected at a data driven treatment threshold. Both algorithms had the best balance of sensitivity/specificity at the moderate risk threshold (>10% risk). Over 12years, 82% and 77% of 401 incident CVD events were accurately predicted via the non-lab and lab-based Framingham algorithms, respectively. There were 20 fewer false negative cases in the non-lab approach translating into over $900,000 in savings over 12years. The ICER was -$57,153 for every extra CVD event prevented when using the non-lab algorithm. The approach guided by the non-lab Framingham strategy dominated the lab-based approach with respect to both costs and predictive ability. Consequently, the non-lab Framingham algorithm could potentially provide a highly effective screening tool at lower cost to address the high burden of CVD especially among AA and in resource-constrained settings where lab tests are unavailable.

Ethnic Differences in Lipid Profiles of Overweight, Obese, and Severely Obese Children and Adolescents 6-19 Years of Age

BACKGROUND

Ethnic differences in lipid profiles exist in children and adolescents. This study assessed whether variations in lipid profiles present in overweight and obese youth were also observed in severely obese youth. Variations could explain the lower prevalence of the metabolic syndrome in certain ethnic groups at even severe levels of obesity.

METHODS

Data were obtained from the National Health and Nutrition Examination Survey for the years of 2001 through 2012. Subjects were divided into groups according to BMI classification. Normal weight was defined as a BMI less than the 85th percentile. Overweight was defined as a BMI between the 85th and 95th percentile. Class 1 obesity was defined as a BMI greater than the 95th percentile up to 120% of the 95th percentile. A BMI between 120% and 140% of the 95th percentile was defined as Class 2 obesity. Class 3 was defined as a BMI above 140% of the 95th percentile. Primary outcomes were mean total cholesterol, triglyceride, low-density lipoprotein, and high-density lipoprotein levels (HDL).

RESULTS

The sample included 14,481 non-Hispanic black (NHB) (N = 4710), non-Hispanic white (N = 4910), and Mexican American (N = 4861) subjects. Across all BMI categories, the NHB group had significantly lower mean TG and higher mean HDL levels (p < 0.0001).

CONCLUSIONS

Ethnic variations in lipid profiles were found in severely obese youth. These findings could explain the lower prevalence of the metabolic syndrome in NHB youth. Ethnic-specific guidelines are necessary for improved identification of those at risk at all levels of obesity.

Maternal Circulating Lipid Profile during Early Pregnancy: Racial/Ethnic Differences and Association with Spontaneous Preterm Delivery

Prior reports on the association between altered maternal serum lipid levels with preterm delivery are inconsistent. Ethnic differences in serum lipids during pregnancy and their relation to preterm delivery have not been studied. We examined the relationships of six maternal lipids during early pregnancy with the risk of spontaneous preterm delivery (SPTD). The design represents a case-control study nested within a large prospective, multiethnic cohort of young, generally healthy pregnant women. SPTD cases (n = 183) and controls who delivered at term (n = 376) were included. SPTD is defined as delivery at <37 completed weeks of gestation without indicated conditions. We found that African-American women had significantly increased levels of high-density lipoprotein cholesterol (HDL-C) and apolipoprotein A1 (apoA1), and lower triglyceride (TG) and apolipoprotein B (apoB) levels compared to Hispanic and non-Hispanic Caucasians combined. Elevated HDL-C and apoA1 concentrations were significantly associated with an increased odds of SPTD after controlling for potential confounding factors. The adjusted odds ratio (AOR) was 1.91 (95% confidence interval (CI) 1.15, 3.20) for the highest quartile of HDL-C relative to the lowest quartile, and for apoA1 the AOR was 1.94 (95% CI 1.16, 3.24). When controlling for ethnicity, the results remained comparable. These data suggest that pregnant African-American women had a more favorable lipid profile suggestive of a reduction in cardiovascular risk. Despite this, increased HDL-C and apoA1 were both found to be associated with SPTD.

Differences in Cardiovascular Disease Risk Factors and Health Behaviors Between Black and Non-Black Students Participating in a School-Based Health Promotion Program

PURPOSE

To compare cardiovascular disease (CVD) risk factors of black and non-black children participating in Project Healthy Schools (PHS), a school-based wellness program.

DESIGN

Participants were surveyed and participated in physiological screenings pre- and post-PHS intervention.

SETTING

Middle schools in 4 Michigan communities of varying socioeconomic status.

PARTICIPANTS

A total of 3813 sixth-grade students comprised the survey sample, and 2297 sixth-grade students comprised the screening sample.

INTERVENTION

Project Healthy Schools is a school-based intervention designed to reduce the risk of obesity and CVD in children through the promotion of healthy eating and physical activity.

MEASURES

Physical examination, blood test, and self-reported survey data on dietary habits, physical activity, and sedentary behaviors were collected pre- and post-PHS.

ANALYSIS

Paired and independent t tests were used for physiologic variables. Wilcoxon sign-rank and rank-sum tests were used for survey variables.

RESULTS

At baseline, blacks had a higher percentage of overweight/obese students (43% vs 34%; P < .0001) and demonstrated poorer health habits than non-blacks; however, non-blacks had poorer lipid profiles. At follow-up (post-PHS intervention), both groups demonstrated significant improvements in physiological measures and health behaviors.

CONCLUSION

Despite disparities between the groups at both baseline and follow-up, changes seen post-PHS intervention were beneficial in both groups. These results suggest that early intervention for risk factor modification is possible and may be of great importance in the prevention of CVD, particularly in high-risk groups.

Relation of longitudinal changes in body mass index with atherosclerotic cardiovascular disease risk scores in middle-aged black and white adults: the Coronary Artery Risk Development in Young Adults (CARDIA) Study

PURPOSE

We assessed whether longitudinal changes in body mass index (BMI) are positively associated with changes in 10-year American College of Cardiology/American Heart Association atherosclerotic cardiovascular disease (ASCVD) risk scores in middle-aged blacks compared to whites.

METHODS

Data were from 1691 participants enrolled in the Coronary Artery Risk Development in Young Adults Study aged 40 years or more in 2000-2001, who had follow-up examinations 5 and 10 years later.

RESULTS

The prevalence of obesity increased from 32.3% in 2000-2001 (mean age: 42.8 years) to 41.7% in 2010-2011, higher in blacks than whites. The corresponding change in 10-year ASCVD risk was significantly higher for blacks (men: 4.5%-9.6%, women: 1.7%-5.0%) than whites (men: 2.4%-5.2%, women: 0.7%-1.6%). In 2010-2011, 57.5% of black men had ASCVD risk scores of 7.5% or more compared to white men (14.7%), black women (17.4%), and white women (1.6%). Although BMI trends were positively associated with 10-year change in ASCVD risk scores (0.07% per 1 kg/m(2) increase), it explained very little variance in risk score trends in all race-sex groups.

CONCLUSIONS

In middle-aged adults, longitudinal changes in BMI had little independent influence on changes in 10-year ASCVD risk scores as its effect may be largely mediated through ASCVD risk factors already accounted for in the risk score.

Differences in lipid measurements by antiretroviral regimen exposure in cohorts from Asia and australia

We explored the mean differences in routinely measured lipids (total cholesterol, triglycerides, and high-density lipoprotein cholesterol) according to exposure to different combination antiretroviral regimens in Asian (n = 2051) and Australian (predominantly Caucasian, n = 794) cohorts. The regimen was defined as at least 3 antiretroviral drugs with at least 2 nucleoside-reverse transcriptases (NRTIs) and either of at least one protease inhibitor (PI) or non-nucleoside-reverse transcriptases (NNRTIs). We categorised cART regimens as: NRTIs as tenofovir based or not; NNRTIs as nevirapine or efavirenz (but not both); and PI as atazanavir based or not. We found that the impact of various antiretroviral regimens on lipids in Asian and Australian cohorts was only different by cohort for total cholesterol (P for interaction between regimen and cohort: <0.001) but not in case of other lipids (P for interaction: >0.05). The differences in total cholesterol were however small and unlikely to be of clinical significance. Overall, tenofovir with nevirapine or atazanavir was associated with the most favorable lipids, while the PI regimens without tenofovir and atazanavir were associated with least favorable lipids. We conclude that the impact of various ART regimens on lipids is largely similar in Asian and Australian cohorts and that the newer drugs such as tenofovir and atazanavir are likely to provide similar benefit in terms of lipid profiles in both populations.