Marc D. Gellman

Prevalence of Major Cardiovascular Risk Factors and Cardiovascular Diseases Among Hispanic/Latino Individuals of Diverse Backgrounds in the United States

CONTEXT Major cardiovascular diseases (CVDs) are leading causes of mortality among US Hispanic and Latino individuals. Comprehensive data are limited regarding the prevalence of CVD risk factors in this population and relations of these traits to socioeconomic status (SES) and acculturation. OBJECTIVES To describe prevalence of major CVD risk factors and CVD (coronary heart disease [CHD] and stroke) among US Hispanic/Latino individuals of different backgrounds, examine relationships of SES and acculturation with CVD risk profiles and CVD, and assess cross-sectional associations of CVD risk factors with CVD. DESIGN, SETTING, AND PARTICIPANTS Multicenter, prospective, population-based Hispanic Community Health Study/Study of Latinos including individuals of Cuban (n = 2201), Dominican (n = 1400), Mexican (n = 6232), Puerto Rican (n = 2590), Central American (n = 1634), and South American backgrounds (n = 1022) aged 18 to 74 years. Analyses involved 15,079 participants with complete data enrolled between March 2008 and June 2011. MAIN OUTCOME MEASURES Adverse CVD risk factors defined using national guidelines for hypercholesterolemia, hypertension, obesity, diabetes, and smoking. Prevalence of CHD and stroke were ascertained from self-reported data. RESULTS Age-standardized prevalence of CVD risk factors varied by Hispanic/Latino background; obesity and current smoking rates were highest among Puerto Rican participants (for men, 40.9% and 34.7%; for women, 51.4% and 31.7%, respectively); hypercholesterolemia prevalence was highest among Central American men (54.9%) and Puerto Rican women (41.0%). Large proportions of participants (80% of men, 71% of women) had at least 1 risk factor. Age- and sex-adjusted prevalence of 3 or more risk factors was highest in Puerto Rican participants (25.0%) and significantly higher (P < .001) among participants with less education (16.1%), those who were US-born (18.5%), those who had lived in the United States 10 years or longer (15.7%), and those who preferred English (17.9%). Overall, self-reported CHD and stroke prevalence were low (4.2% and 2.0% in men; 2.4% and 1.2% in women, respectively). In multivariate-adjusted models, hypertension and smoking were directly associated with CHD in both sexes as were hypercholesterolemia and obesity in women and diabetes in men (odds ratios [ORs], 1.5-2.2). For stroke, associations were positive with hypertension in both sexes, diabetes in men, and smoking in women (ORs, 1.7-2.6). CONCLUSION Among US Hispanic/Latino adults of diverse backgrounds, a sizeable proportion of men and women had adverse major risk factors; prevalence of adverse CVD risk profiles was higher among participants with Puerto Rican background, lower SES, and higher levels of acculturation.

Smoking among U.S. hispanic/latino adults: The hispanic community health study/study of latinos

BACKGROUND Prior national surveys capture smoking behaviors of the aggregated U.S. Hispanic/Latino population, possibly obscuring subgroup variation. PURPOSE To describe cigarette use among Hispanic/Latino adults across subgroups of age, gender, national background, SES, birthplace, and degree of acculturation to the dominant U.S. culture. METHODS A cross-sectional survey of 16,322 participants in the Hispanic Community Health Study/Study of Latinos aged 18-74 years, recruited in Bronx NY, Chicago IL, Miami FL, and San Diego CA, was conducted during 2008-2011. RESULTS Prevalence of current smoking was highest among Puerto Ricans (men, 35.0%; women, 32.6%) and Cubans (men, 31.3%; women, 21.9%), with particularly high smoking intensity noted among Cubans as measured by pack-years and cigarettes/day. Dominicans had the lowest smoking prevalence (men, 11.0%; women, 11.7%). Individuals of other national backgrounds had a smoking prevalence that was intermediate between these groups, and typically higher among men than women. Non-daily smoking was common, particularly although not exclusively among young men of Mexican background. Persons of low SES were more likely to smoke, less likely to have quit smoking, and less frequently used over-the-counter quit aids compared to those with higher income and education levels. Smoking was more common among individuals who were born in the U.S. and had a higher level of acculturation to the dominant U.S. culture, particularly among women. CONCLUSIONS Smoking behaviors vary widely across Hispanic/Latino groups in the U.S., with a high prevalence of smoking among population subgroups with specific, readily identifiable characteristics.

Cardiovascular responsivity to stress in adolescents with and without persistently elevated blood pressure

Objectives The goal of this study was to compare the cardiovascular responses to behavioural stressors of three groups of adolescents who differed in blood pressure status across assessments. Design Casual blood pressure of adolescents who were identified as having elevated blood pressure during a school screen was re-evaluated in the laboratory. The adolescents were classified into two groups: (i) those with consistently elevated blood pressure across school and laboratory assessments and (i) those with labile blood pressure whose blood pressure in the laboratory was below 130/80 mmHg. A comparison group of adolescents with consistently normal blood pressure was also included. Methods Cardiovascular parameters were assessed during rest and during two behavioural stressors, the evaluated speaking task and the mirror tracing task. Results Adolescents with elevated blood pressure were more vascularly responsive across stressors than adolescents with labile blood pressure, who, in turn, were more reactive than adolescents with normal blood pressure. Conclusions These results suggest that vascular reactivity to behavioural stressors may be useful in predicting risk of hypertension because of its sensitivity in distinguishing adolescents with consistently elevated blood pressure from those with labile blood pressure and those with normal blood pressure.

The influence of social situations on ambulatory blood pressure

&NA; Ambulatory blood pressure (BP) levels were assessed and types of activities were recorded every 20 min for a 12‐hr period in 131 normotensive or mild‐moderate hypertensive subjects. Systolic (S)BP and diastolic (D)BP levels varied significantly as a function of the social situation (alone, with family, with friends, or with strangers). BP levels were lowest when subjects were with family and were highest when subjects were with strangers.

Differential patterns of dynamic cardiovascular regulation as a function of task

In cardiovascular reactivity studies, interpretations of the processes supporting the blood pressure response may become problematic when systolic blood pressure, diastolic blood pressure, and heart rate all increase in response to a behavioral challenge. Therefore, in addition to evaluating these cardiovascular responses, this study examined cardiac output, total peripheral resistance and systolic time intervals derived from impedance cardiogram, electrocardiogram and phonocardiogram recordings during a speech stressor, a mirror tracing task, and a foot cold pressor test. All of the behavioral stressors elicited increases in blood pressure and heart rate, with the largest changes occurring during the overt speech. Based on the examination of the response patterns of the underlying hemodynamic variables it would appear that, in both men and women, the blood pressure increase during the speech preparation period was supported by increased cardiac output; the speech itself resulted in a mixed pattern of increased cardiac output and total peripheral resistance; whereas, the mirror tracing and cold pressor tasks produced increased total peripheral resistance. Although men and women produced similar response patterns to the behavioral challenges, sex differences in the estimates of myocardial contractility were observed during rest. These results provide evidence that different behavioral stressors can produce a distinct yet integrated pattern of responses, whose differences may be revealed, when impedance cardiography is used, to derive sufficient response measures for assessing dynamic cardiovascular processes.

History of Gestational Diabetes, Insulin Resistance and Coronary Risk

The purpose of this study was to examine characteristics associated with the insulin metabolic syndrome, including insulin resistance, abnormal glucose tolerance, dyslipidemia, obesity, and elevated blood pressure, among women who have experienced gestational diabetes. 39 nondiabetic, young (20-42 years), postpartum (3-18 months) white women were recruited from obstetrical clinics. Twenty-one women had a history of gestational diabetes; 18 had uncomplicated pregnancies. Multivariate analyses revealed a significant difference between groups in insulin resistance (M, measured by euglycemic clamp) and insulin levels (from an oral glucose tolerance test), with insulin resistance showing a statistically stronger difference than insulin levels. Groups also differed significantly when compared on a set of variables associated with insulin metabolic syndrome: glucose tolerance, triglycerides, blood pressure, and body-mass index. Using insulin resistance as a covariate eliminated these group differences, suggesting that insulin resistance is the key factor underlying insulin metabolic syndrome. The higher risk of later developing type 2 diabetes and hypertension in women who have a history of gestational diabetes is explicable by their poorer profile on variables associated with insulin metabolic syndrome, and appears to be attributable to insulin resistance. Thus, insulin resistance appears to distinguish young women at risk for cardiovascular disease.

Food-group and nutrient-density intakes by Hispanic and Latino backgrounds in the Hispanic Community Health Study/Study of Latinos

BACKGROUND Hispanics are a heterogeneous group of individuals with a variation in dietary habits that is reflective of their cultural heritage and country of origin. It is important to identify differences in their dietary habits because it has been well established that nutrition contributes substantially to the burden of preventable diseases and early deaths in the United States. OBJECTIVE We estimated the distribution of usual intakes (of both food groups and nutrients) by Hispanic and Latino backgrounds by using National Cancer Institute methodology. DESIGN The Hispanic Community Health Study/Study of Latinos is a population-based cohort study that recruited participants who were 18-74 y of age from 4 US cities in 2008-2011 (Miami, Bronx, Chicago, and San Diego). Participants who provided at least one 24-h dietary recall and completed a food propensity questionnaire (n = 13,285) were included in the analyses. Results were adjusted for age, sex, field center, weekend, sequencing, and typical amount of intake. RESULTS Overall, Cubans (n = 2128) had higher intakes of total energy, macronutrients (including all subtypes of fat), and alcohol than those of other groups. Mexicans (n = 5371) had higher intakes of vitamin C, calcium, and fiber. Lowest intakes of total energy, macronutrients, folate, iron, and calcium were reported by Dominicans (n = 1217), whereas Puerto Ricans (n = 2176) had lowest intakes of vitamin C and fiber. Food-group servings reflected nutrient intakes, with Cubans having higher intakes of refined grains, vegetables, red meat, and fats and Dominicans having higher intakes of fruit and poultry, whereas Puerto Ricans had lowest intakes of fruit and vegetables. Central and South Americans (n = 1468 and 925, respectively) were characterized by being second in their reported intakes of fruit and poultry and the highest in fish intake in comparison with other groups. CONCLUSION Variations in diet noted in this study, with additional analysis, may help explain diet-related differences in health outcomes observed in Hispanics and Latinos.

Cardiovascular responses elicited by hypothalamic stimulation in rabbits reveal a mediolateral organization

Heart rate and blood pressure response patterns were elicited by relatively low intensity (approximately 0.2 mA) stimulation (10 s trains; 100 pulses/s; 0.25 ms pulse duration) in different regions of the hypothalamus in anesthetized rabbits. A bradycardia/depressor pattern was elicited from both anterior and posterior stimulating electrode sites in the far lateral hypothalamus. Medial sites including the ventromedial hypothalamus elicited a tachycardia/pressor pattern. A bradycardia/pressor pattern was elicited from both the anterior and posterior hypothalamus at sites between the lateral hypothalamic (bradycardia/depressor) and the medial hypothalamic (tachycardia/pressor) zones. Paralysis by injection of decamethonium in conjunction with artificial ventilation did not reveal systematic differences in cardiovascular response threshold, form, or magnitude between the paralyzed and non-paralyzed state, indicating that the cardiovascular response patterns were not secondary to changes in respiration. Bilateral vagotomy abolished the bradycardia responses evoked by hypothalamic stimulation indicating that the cardiodeceleration was mediated by the vagus nerves; vagotomy attenuated tachycardia responses indicating that the responses in part reflected a decrease in vagal restraint. Bradycardia responses to ipsilateral but not contralateral hypothalamic stimulation were attenuated or abolished when examined 10-14 days after unilateral destruction of the central nucleus of the amygdala. This indicates that the bradycardia responses elicited by hypothalamic stimulation are in part mediated by fibers of passage. Stimulation of lateral hypothalamic sites eliciting a bradycardia/depressor pattern in anesthetized rabbits, evoked mild orienting in the same animals when conscious, whereas medial hypothalamic sites producing the tachycardia/pressor response pattern in anesthetized animals elicited intense excitement with autonomic concomitants in the nonanesthetized state. The results indicate that the rabbit hypothalamus has a mediolateral organization in terms of at least some cardiovascular and behavioral responses to intracranial stimulation.

Applying Recovery Biomarkers to Calibrate Self-Report Measures of Energy and Protein in the Hispanic Community Health Study/Study of Latinos

We investigated measurement error in the self-reported diets of US Hispanics/Latinos, who are prone to obesity and related comorbidities, by background (Central American, Cuban, Dominican, Mexican, Puerto Rican, and South American) in 2010–2012. In 477 participants aged 18–74 years, doubly labeled water and urinary nitrogen were used as objective recovery biomarkers of energy and protein intakes. Self-report was captured from two 24-hour dietary recalls. All measures were repeated in a subsample of 98 individuals. We examined the bias of dietary recalls and their associations with participant characteristics using generalized estimating equations. Energy intake was underestimated by 25.3% (men, 21.8%; women, 27.3%), and protein intake was underestimated by 18.5% (men, 14.7%; women, 20.7%). Protein density was overestimated by 10.7% (men, 11.3%; women, 10.1%). Higher body mass index and Hispanic/Latino background were associated with underestimation of energy (P < 0.05). For protein intake, higher body mass index, older age, nonsmoking, Spanish speaking, and Hispanic/Latino background were associated with underestimation (P < 0.05). Systematic underreporting of energy and protein intakes and overreporting of protein density were found to vary significantly by Hispanic/Latino background. We developed calibration equations that correct for subject-specific error in reporting that can be used to reduce bias in diet-disease association studies.

Leptin and its Association with Somatic Depressive Symptoms in Patients with the Metabolic Syndrome

BackgroundThis study aimed to determine the association between circulating leptin levels and total depressive symptoms as well as depressive symptom dimensions (cognitive and somatic) after controlling for important confounding factors.MethodsThe study sample was comprised of 135 participants with the metabolic syndrome. Depressive symptoms were measured using the Beck Depression Inventory—II. Leptin was measured using a leptin-specific enzyme immunoassay. Inflammation was assessed using C-reactive protein and interleukin-6 levels.ResultsLeptin was significantly associated with somatic depressive symptoms (β = 0.33, P = 0.018), but not total depressive symptoms (β = 0.27, P = 0.067) or cognitive depressive symptoms (β = 0.21, P = 0.182), after controlling for age, gender, body mass index, and insulin resistance. Further adjustment for C-reactive protein and interleukin-6 levels did not alter the relationship (β = 0.32, P = 0.023) between circulating leptin levels and somatic depressive symptoms.ConclusionsLeptin is independently associated with somatic depressive symptoms in patients with the metabolic syndrome.