Reduced circulating adiponectin levels contribute to the etiology of insulin-resistance. Adiponectin circulates in three different isoforms: high (HMW), medium (MMW), and low (LMW) molecular weight. The genetics of adiponectin isoforms is mostly unknown. Our aim was to investigate whether and to which extent circulating adiponectin isoforms are heritable and whether they share common genetic backgrounds with insulin resistance-related traits.
In a family based sample of 640 non diabetic White Caucasians from Italy, serum adiponectin isoforms concentrations were measured by ELISA. Three SNPs in the ADIPOQ gene previously reported to affect total adiponectin levels (rs17300539, rs1501299 and rs677395) were genotyped. The heritability of adiponectin isoform levels was assessed by variance component analysis. A linear mixed effects model was used to test association between SNPs and adiponectin isoforms. Bivariate analyses were conducted to study genetic correlations between adiponectin isoforms levels and other insulin resistance-related traits.
All isoforms were highly heritable (h2=0.60−0.80, p=1×10−13–1×10−23). SNPs rs17300539, rs1501299 and rs6773957 explained a significant proportion of HMW variance (2–9%, p=1×10−3–1×10−5). In a multiple-SNP model, only rs17300539 and rs1501299 remained associated with HMW adiponectin (p=3×10−4 and 2.0×10−2). Significant genetic correlations (p=1×10−2–1×10−5) were observed between HMW adiponectin and fasting insulin, HOMAIR, HDL-cholesterol and the metabolic syndrome score. Only rs1501299 partly accounted for these genetic correlations.
Circulating levels of adiponectin isoforms are highly heritable. The genetic control of HMW adiponectin is shared in part with insulin resistance-related traits and involves, but is not limited to the ADIPOQ locus.
ADIPOQ gene; Adiponectin isoforms; insulin resistance
The aim of this study was to determine whether retinol-binding protein 4 (RBP4), adiponectin and high molecular weight (HMW) adiponectin are associated with insulin resistance (IR) and metabolic parameters in non-diabetic hypertensive patients. Also, we sought to compare the predictive values of these adipocytokines for IR in non-diabetic hypertensive patients.
Materials and Methods
Analyses of RBP4, adiponectin, and HMW adiponectin were performed on 308 non-diabetic hypertensives (148 males, age 58 ± 10 years, 189 non-metabolic syndrome and 119 metabolic syndrome). The homeostasis model assessment (HOMA) index for IR, lipid profiles, and anthropometric measure-ments were assessed.
There was no significant difference in RBP4 levels according to the presence of metabolic syndrome, although adiponectin and HMW adiponectin were significantly lower in metabolic syndrome. Correlation analysis of log RBP4 with IR and metabolic indices revealed that there was no significant correlation of RBP4 with waist circumference (r = 0.056, p = 0.324), HDL cholesterol (r = 0.005, p = 0.934), ApoB/ApoAI ratio (r = 0.066, p = 0.270), and the HOMA index (r = 0.017, p = 0.756). However, adiponectin and HMW adiponectin showed significant correlations with the HOMA index (r = - 0.247, p < 0.001; r = - 0.296, p < 0.001) and metabolic parameters. With IR defined as HOMA index ≥ 2.5, HMW adiponectin did not demonstrate a superior predictive value for IR compared to adiponectin (AUC = 0.680 vs. 0.648, p = 0.083). The predictive value of RBP4 for IR was minimal (AUC = 0.534).
RBP4 was not associated with IR or metabolic indices and the predictive value for IR was minimal in hypertensives. HMW adiponectin didn't have a superior predictive value for IR compared to adiponectin. Therefore, we can suggest that RBP4 and HMW adiponectin don't have more additive information than adiponectin in non-diabetic hypertensives.
Retinol-binding proteins; adiponectin; hypertension; insulin resistance
There is limited information on whether recent improvements in the control of cardiovascular disease (CVD) risk factors among individuals with diabetes have been concentrated in particular sociodemographic groups. This article estimates racial/ethnic- and education-related disparities and examines trends in uncontrolled CVD risk factors among adults with diabetes. The main racial/ethnic comparisons made are with African Americans versus non-Latino whites and Mexican Americans versus non-Latino whites.
RESEARCH DESIGN AND METHODS
The analysis samples include adults aged ≥20 years from the National Health and Nutrition Examination Survey (NHANES) 1988–1994 and the NHANES 1999–2008 who self-reported having diabetes (n = 1,065, NHANES 1988–1994; n = 1,872, NHANES 1999–2008). By use of logistic regression models, we examined the correlates of binary indicators measuring 1) high blood glucose, 2) high blood pressure, 3) high cholesterol, and 4) smoking.
Control of blood glucose, blood pressure, and cholesterol improved among individuals with diabetes between the NHANES 1988–1994 and the NHANES 1999–2008, but there was no change in smoking prevalence. In the NHANES 1999–2008, racial/ethnic minorities and individuals without some college education were more likely to have poorly controlled blood glucose compared with non-Latino whites and those with some college education. In addition, individuals with diabetes who had at least some college education were less likely to smoke and had better blood pressure control compared with individuals with diabetes without at least some college education.
Trends in CVD risk factors among individuals with diabetes improved over the past 2 decades, but racial/ethnic- and education-related disparities have emerged in some areas.
Background and purpose
Adiponectin is an insulin-sensitizing plasma protein expressed in adipose tissue and suggested to play a role in atherosclerosis and cardiovascular disease. Data are lacking on the relationship between adiponectin and carotid intima-media thickness (IMT) in ethnically heterogeneous populations. We examined the relationship between adiponectin and IMT, a marker of atherosclerosis, in a multi-ethnic cohort study of stroke risk factors.
Participants were from the Northern Manhattan Study (N=1522, mean age 66±9 years, 60% female, 20% black, 18% white, 60% Hispanic). Adiponectin was measured from baseline plasma samples and IMT was assessed by high-resolution B-mode carotid ultrasound. Regression models were used to examine the association between adiponectin, assessed continuously and in quartiles, and IMT, controlling for demographics and vascular risk factors.
The mean adiponectin level was 10.3±5.2 μg/ml (median=9.2, range=2.3-53.3), and the mean IMT was 0.91±0.08 mm. Adiponectin was inversely associated with IMT, even after controlling for demographics and vascular risk factors. Individuals in the first quartile of adiponectin had mean IMT that was on average 0.02 mm greater than those in the top quartile. The relationship between adiponectin and IMT appeared to be stronger among those with diabetes.
Our findings suggest that low adiponectin is associated with increased IMT in a multi-ethnic cohort and support a protective role for adiponectin in atherosclerosis.
Adiponectin; carotid artery; intima-media thickness; atherosclerosis; epidemiology
Latino and African American children with asthma are at increased risk for asthma morbidity compared with non–Latino White children. Environmental control (ie, environmental exposures and family strategies to control them) may contribute to greater asthma morbidity for ethnic minority children living in urban environments. This study examined ethnic differences in a semi-structured assessment of environmental control, associations between environmental control and asthma outcomes (asthma control, functional limitation, and emergency department [ED] use), and ethnic differences in environmental triggers in a sample of urban Latino, African American, and non–Latino White families. One hundred thirty-three children (6–13 years of age) and their caregivers completed demographic questionnaires, measures of asthma control and morbidity, and a semi-structured interview assessing environmental control. Reported environmental control differed significantly by ethnicity (P<0.05), with Latino families reporting higher levels of environmental control. Reported environmental control was significantly associated with asthma control (P<0.017) and functional limitation (P<0.017). Reported environmental control and ED use were significantly associated in Latino families (P<0.05). Non–Latino White and African American families reported more secondhand smoke exposure than Latino families (P<0.001). Latino families reported more optimal home environmental control than other ethnic groups. Substantial ethnic differences in asthma triggers suggest that observed ethnic disparities in asthma may be due, at least in part, to differences in the home environment.
Adiponectin—an adipose tissue-derived protein—may provide a molecular link between obesity and colorectal cancer (CRC), but evidence from large prospective studies is limited. In particular, no epidemiological study explored high-molecular weight (HMW) and non-HMW adiponectin fractions in relation to CRC risk, despite them being hypothesized to have differential biological activities, i.e. regulating insulin sensitivity (HMW adiponectin) versus inflammatory response (non-HMW adiponectin). In a prospective, nested case–control study, we investigated whether prediagnostic serum concentrations of total, HMW and non-HMW adiponectin are associated with risk of CRC, independent of obesity and other known CRC risk factors. A total of 1206 incident cases (755 colon and 451 rectal) were matched to 1206 controls using incidence-density sampling. In conditional logistic regression, adjusted for dietary and lifestyle factors, total adiponectin and non-HMW adiponectin concentrations were inversely associated with risk of CRC [relative risk (RR) comparing highest versus lowest quintile = 0.71, 95% confidence interval (CI) = 0.53–0.95, P
trend = 0.03 for total adiponectin and RR = 0.45, 95% CI = 0.34–0.61, P
trend < 0.0001 for non-HMW adiponectin]. HMW adiponectin concentrations were not associated with CRC risk (RR = 0.91, 95% CI = 0.68–1.22, P
trend = 0.55). Non-HMW adiponectin was associated with CRC risk even after adjustment for body mass index and waist circumference (RR = 0.39, 95% CI = 0.26–0.60, P
trend < 0.0001), whereas the association with total adiponectin was no longer significant (RR = 0.81, 95% CI = 0.60–1.09, P
trend = 0.23). When stratified by cancer site, non-HMW adiponectin was inversely associated with both colon and rectal cancer. These findings suggest an important role of the relative proportion of non-HMW adiponectin in CRC pathogenesis. Future studies are warranted to confirm these results and to elucidate the underlying mechanisms.
Population-based data on serum adiponectin levels, an adipocytokine secreted from adipose tissue, are lacking, particularly across race–ethnic groups. Studies have suggested an inverse association between adiponectin and vascular risk factors, but data are limited and inconsistent. We examined the cross-sectional association between adiponectin, vascular risk factors and race–ethnicity in the population-based Northern Manhattan Study (NOMAS).
Blood samples, anthropomorphics, and vascular risk factors were collected at baseline. Multivariable linear regression analysis was conducted with log-transformed adiponectin as the dependent variable.
Adiponectin was measured among 2900 participants (age 69±10 years, body mass index (BMI) 28.0±5.6, 37% male, 21% white, 53% Hispanic, 24% black). The mean adiponectin was 11.4±6.2 μg/mL (median=9.8, range=2.1–53.3). After multivariable adjustment, adiponectin levels were greatest among whites, followed by Hispanics, and lowest among blacks. Lower adiponectin levels were observed in participants with the following characteristics: Male, former smoking, hypertension, diabetes, homeostasis model assessment of insulin resistance (HOMA-IR), metabolic syndrome, moderate alcohol use, elevated waist circumference, BMI, estimated glomerular filtration rate (eGFR), triglycerides, low-density lipoprotein cholesterol (LDL-C), lower high-density lipoprotein cholesterol (HDL-C), and younger age. Obesity was a stronger risk factor for decreased adiponectin among blacks than among whites or Hispanics. The associations for several vascular risk factors, including hypertension, triglycerides, and low HDL-C, with low adiponectin were stronger among individuals who were not obese than among those who were obese.
Adiponectin levels were lower among blacks and Hispanics and among those with various vascular risk factors, and greater with older age. The association between BMI and adiponectin varied across race–ethnic groups. Investigation of whether differences in body fat distribution may explain race–ethnic differences in adiponectin is needed.
Rationale: Disparities in pediatric asthma exist in that Latino children have higher prevalence and greater morbidity from asthma than non–Latino white children. The factors behind these disparities are poorly understood, but ethnic-related variations in children's ability to accurately recognize and report their pulmonary functioning may be a contributing process.
Objectives: To determine (1) if differences exist between Latino and non–Latino white children's perceptual accuracy and (2) whether these differences are related to asthma outcomes.
Methods: Five hundred and twelve children, aged 7–16 years (290 island Puerto Ricans, 115 Rhode Island Latinos, and 107 Rhode Island non-Latino white children) participated in a 5-week home-based protocol in which twice daily they entered subjective estimates of their peak expiratory flow rate into a hand-held, programmable spirometer and then performed spirometry. Their accuracy was summarized as three perceptual accuracy scores. Demographic data, asthma severity, intelligence, emotional expression, and general symptom-reporting tendencies were assessed and covaried in analyses of the relationship of perceptual accuracy to asthma morbidity and health care use.
Measurements and Main Results: Younger age, female sex, lower intelligence, and poverty were associated with lower pulmonary function perception scores. Island Puerto Rican children had the lowest accuracy and highest magnification scores, followed by Rhode Island Latinos; both differed significantly from non–Latino white children. Perceptual accuracy scores were associated with most indices of asthma morbidity.
Conclusions: Controlling for other predictive variables, ethnicity was related to pulmonary function perception ability, as Latino children were less accurate than non–Latino white children. This difference in perceptual ability may contribute to recognized asthma disparities.
childhood asthma; symptom recognition; disparities
The prevalence of depression is increasing not only among adults, but also among adolescents. Several risk factors for depression in youth have been identified, including female gender, increasing age, lower socio-economic status, and Latino ethnic background. The literature is divided regarding the role of acculturation as risk factor among Latino youth. We analyzed the correlates of depressive symptoms among Latino and Non-Latino White adolescents residing in California with a special focus on acculturation.
We performed an analysis of the adolescent sample of the 2003 California Health Interview Survey, which included 3,196 telephone-interviews with Latino and Non-Latino White adolescents between the ages of 12 and 17. Depressive symptomatology was measured with a reduced version of the Center for Epidemiologic Studies Depression Scale. Acculturation was measured by a score based on language in which the interview was conducted, language(s) spoken at home, place of birth, number of years lived in the United States, and citizenship status of the adolescent and both of his/her parents, using canonical principal component analysis. Other variables used in the analysis were: support provided by adults at school and at home, age of the adolescent, gender, socio-economic status, and household type (two parent or one parent household).
Unadjusted analysis suggested that the risk of depressive symptoms was twice as high among Latinos as compared to Non-Latino Whites (10.5% versus 5.5 %, p < 0.001). The risk was slightly higher in the low acculturation group than in the high acculturation group (13.1% versus 9.7%, p = 0.12). Similarly, low acculturation was associated with an increased risk of depressive symptoms in multivariate analysis within the Latino subsample (OR 1.54, CI 0.97–2.44, p = 0.07). Latino ethnicity emerged as risk factor for depressive symptoms among the strata with higher income and high support at home and at school. In the disadvantaged subgroups (higher poverty, low support at home and at school) Non-Latino Whites and Latinos had a similar risk of depressive symptoms.
Our findings suggest that the differences in depressive symptoms between Non-Latino Whites and Latino adolescents disappear at least in some strata after adjusting for socio-demographic and social support variables.
To determine if hypothesized differences in attitudes and beliefs about cigarette smoking between Latino and non-Latino white smokers are independent of years of formal education and number of cigarettes smoked per day.
Cross-sectional survey using a random digit dial telephone method.
San Francisco census tracts with at least 10% Latinos in the 1990 Census.
Three hundred twelve Latinos (198 men and 114 women) and 354 non-Latino whites (186 men and 168 women), 18 to 65 years of age, who were current cigarette smokers participated.
MEASUREMENTS AND MAIN RESULTS
Self-reports of cigarette smoking behavior, antecedents to smoking, reasons to quit smoking, and reasons to continue smoking were the measures. Latino smokers were younger (36.6 vs 39.6 years, p < .01), had fewer years of education (11.0 vs 14.3 years, p < .001), and smoked on average fewer cigarettes per day (9.7 vs 20.1, p < .001). Compared with whites, Latino smokers were less likely to report smoking “almost always or often” after 13 of 17 antecedents (each p < .001), and more likely to consider it important to quit for 12 of 15 reasons (each p < .001). In multivariate analyses after adjusting for gender, age, education, income, and number of cigarettes smoked per day, Latino ethnicity was a significant predictor of being less likely to smoke while talking on the telephone (odds ratio [OR] 0.41; 95% confidence interval [CI] 0.26, 0.64), drinking alcoholic beverages (OR 0.66; 95% CI 0.44, 0.99), after eating (OR 0.55, 95% CI 0.37, 0.81), or at a bar (OR 0.62, 95% CI 0.41, 0.94), and a significant predictor of being more likely to smoke at a party (OR 1.72; 95% CI 1.14, 2.60). Latino ethnicity was a significant predictor of considering quitting important because of being criticized by family (OR 1.93; 95% CI 1.26, 2.98), burning clothes (OR 1.57; 95% CI 1.02, 2.42), damaging children's health (OR 1.67; 95% CI 1.08, 2.57), bad breath (OR 2.07; 95% CI 1.40, 3.06), family pressure (OR 1.67; 95% CI 1.10, 2.60), and being a good example to children (OR 1.83; 95% CI 1.21, 2.76).
Differences in attitudes and beliefs about cigarette smoking between Latinos and whites are independent of education and number of cigarettes smoked. We recommend that these ethnic differences be incorporated into smoking cessation interventions for Latino smokers.
cigarette smoking; Latinos; Hispanics; culture
The purposes of this study were to examine (a) differences in spiritual perspectives and practices of Latino and non-Latino young adults and (b) the cultural relevance of the Latino Spiritual Perspective Scale (LSPS). Studies indicate that spiritual perspectives are embedded within cultural group norms and vary significantly across ethnic groups. A cross-sectional survey design was used with a convenience sample of 223 Latino and non-Latino university students in the Southwestern United States. The Spiritual Perspective Scale (SPS), the LSPS, the Orthogonal Cultural Identification Scale, and a demographic questionnaire were used. Latinos scored significantly higher than non-Latinos in both measures of spiritual perspectives. Self-reported behavioral measures, such as frequency of personal prayer, were also higher among the Latino group. Latino cultural identification was the only significant predictor of LSPS scores. Findings from this study indicate that spirituality among Latinos has meanings specific to the cultural group context. These findings have implications for nursing research involving the conceptualization and measurement of spirituality among multiethnic groups.
Los propósitos de este estudio eran examinar: (a) diferencias en perspectivas espirituales y prácticas de jóvenes Latinos y no Latinos; y (b) la relevancia cultural de la Escala de la Perspectiva Espiritual Latina. Estudios indican que perspectivas espirituales están incrustadas entre normas culturales del grupo y varían considerablemente entre grupos étnicos. Un diseño transversal y de encuesta fue utilizado con una muestra de conveniencia de 233 estudiantes universitarios Latinos y no Latinos en el Suroeste de los Estados Unidos. La Escala de la Perspectiva Espiritual (EPE), la Escala de la Perspectiva Espiritual Latina (EPEL), la Escala Ortogonal de Identificación Cultural, y un cuestionario demográfico fueron utilizados. Los Latinos calificaron considerablemente más alto que los no Latinos en ambas medidas de perspectivas espirituales. Medidas de comportamiento auto-reportadas, como la frecuencia de oración, también estuvieron más altas en el grupo Latino. La identificación con la cultura Latina fue el único vaticinador de las calificaciones de la EPEL. Los resultados de este estudio indican que la espiritualidad entre Latinos tiene significados específicos al contexto del grupo cultural. Estas conclusiones tienen implicaciones para las investigaciones de enfermería que involucran la conceptualización y medida de la espiritualidad entre grupos multiétnicos.
spirituality; religious practices; cultural identification; instrumentation
To document disparities in health status, activity limitations, and disability in work and housework between Latinos and non-Latino whites with arthritis. We examined whether sociodemographic factors (age, income, and education) account for the disparities between the ethnic groups, and whether comorbid conditions, disease duration, health care utilization, and functional abilities predict health status, activity limitations, and work and housework disability after controlling for sociodemographic variables.
We analyzed data from the Condition file of the 1994 National Health Interview Survey on Disability, Phase I.
The risk of worse health, activity limitations, and work and housework disability was >2 times greater among Latinos compared with non-Latino whites. In the regression models accounting for potential confounders, Latino ethnicity remained significantly associated with poorer health status, but not activity limitations or disability in work or housekeeping. Of the socioeconomic status variables, education had a significant protective effect on work disability and health status. Comorbid conditions and health care utilization increased the likelihood of worse health, activity limitations, and work disability. Limitations in physical function were associated with poorer health and disability in work and homemaking.
Social status differences between Latinos and non-Latinos may account for disparities in activity limitations and disability in work and housework. Education may provide various health benefits, including access to a range of occupations that do not require physical demands. The findings help to address the great gap in knowledge concerning factors related to the health and disability status of Latinos with arthritis.
Latinos; Hispanics; Limitations; Work disability; Housework disability
The aim of this study was to determine ethnic and site differences in quality of life (QOL) in a sample of Latino (Puerto Rican and Dominican) and non-Latino White (NLW) caregivers of children with asthma in mainland US and Island PR. We also investigated ethnic and site differences in associations between caregiver QOL and indicators of asthma morbidity.
Seven-hundred and eighty-seven children with asthma (7–16 years of age) and their primary caregivers participated. Primary caregivers completed a measure of QOL, child asthma control, and emergency department utilization, among other measures.
Ethnic and site differences were found on total QOL scores (ΔF(1, 783) = 29.46, p < .001). Island PR caregivers reported worse QOL scores than RI Latino and NLW caregivers; RI Latino caregivers reported significantly worse QOL scores than NLW caregivers. In RI Latino and Island PR children, worse caregiver QOL was associated with asthma that was not in control and with 1 or more ED visits.
Latino caregivers may be experiencing a greater level of burden related to their child’s asthma than NLW caregivers. Caregiver QOL in pediatric asthma may be a reflection of broader, contextual stress that some Latino caregivers experience on a daily basis (e.g., cultural beliefs, acculturation). Future research should continue to investigate mechanisms that explain the burden associated with pediatric asthma in Latino families, as well as whether QOL assessments should consider the impact of everyday stressors on caregiver QOL in pediatric asthma.
pediatric asthma; quality of life; caregivers; disparities; ethnicity
Language barriers among some Latinos may contribute to the lower rates of colorectal cancer (CRC) screening between Latinos and non-Latino Whites. The purpose of this study was to examine the relationship between language and receipt of colorectal cancer screening tests among Latinos and non-Latinos using a geographically diverse, population-based sample of adults.
Cross-sectional analysis of the Behavioral Risk Factor Surveillance System (BRFSS) survey. Analysis included adults 50 years of age and older, who completed the 2006 BRFSS in a state that recorded data from English and Spanish-speaking participants.
The primary outcome measure was receipt of colorectal screening tests (fecal occult blood testing within prior 12 months and/or lower endoscopy within 10 years). Of the 99,895 respondents included in the study populations, 33% of Latinos responding-in-Spanish reported having had CRC testing, while 51% of Latinos responding-in-English and 62% of English-speaking non-Latinos reported test receipt. In multivariable analysis, compared to non-Latinos, Latinos responding-in-English were 16% less likely (OR,0.84, 95 % CI, 0.73-0.98), and Latinos responding-in-Spanish were 43% less likely to have received colorectal cancer testing (OR,0.57, 95% CI, 0.44-0.74). Additionally, compared to Latinos responding-in-English, Latinos responding-in-Spanish were 36% less likely to have received CRC testing (OR, 0.64; 95% CI, 0.48-0.84)
Latinos responding to the 2006 BRFSS survey in Spanish had a significantly lower likelihood of receiving CRC screening tests compared to non-Latinos and to Latinos responding-in-English. Based on this analysis, Spanish language use is negatively associated with CRC screening and may contribute to disparities in CRC screening.
Colorectal cancer; Screening; Latino/Hispanic; Language; BRFSS
To investigate the importance of a maternal and paternal family history of Type 2 diabetes and their combined association with plasma leptin and adiponectin levels in overweight Latino children with a family history of Type 2 diabetes (T2DM).
This cross-sectional study investigated the combined association of a maternal and paternal family history of T2DM with leptin and adiponectin in 175 overweight Latino children (age 11.1 ± 1.7 years). All subjects had a family history of T2DM. Plasma adiponectin and leptin levels, body fat measured by dual-energy X-ray absorptiometry, Tanner stage, age and insulin sensitivity were assessed.
After adjustment for age, gestational diabetes, insulin sensitivity and body fat, a combined maternal and paternal family history of T2DM was associated with higher leptin concentrations (P = 0.004) compared with a maternal or paternal family history alone. This association was most pronounced at Tanner stage 1 (P for interaction family history × tanner stage = 0.022). The presence of a combined maternal and paternal family history of T2DM accounted for 4% (P = 0.003) of the variation in leptin concentrations. No such combined association was observed for adiponectin levels.
Maternal and paternal family history of T2DM may have an additive impact on leptin, but not on adiponectin levels independent of adiposity and insulin sensitivity in overweight Latino children. This may contribute to a further clinically relevant deterioration of metabolic health in this population.
Diabet. Med. 25, 1043–1048 (2008)
adiponectin; leptin; diabetes
Obesity-related disorders are closely associated with the pathogenesis of cardiovascular disease. Adiponectin is a circulating adipose tissue-derived hormone that is down-regulated in obese individuals. Hypoadiponectinemia has been identified as an independent risk factor for type 2 diabetes, coronary artery disease, and hypertension, and experimental studies show that adiponectin plays a protective role in the development of insulin resistance, atherosclerosis, and inflammation. More recent findings have shown that adiponectin directly affects signaling in myocardial cells and exerts beneficial actions on the heart after pressure overload and ischemia–reperfusion injury. This review focuses on the role of adiponectin in the regulation of myocardial remodeling and acute cardiac injury.
Adiponectin is an adipocyte hormone that links visceral adiposity with insulin resistance and atherosclerosis. It is unique among adipocyte-derived hormones in that its circulating concentrations are inversely proportional to adiposity, and low adiponectin concentrations predict the development of type 2 diabetes and cardiovascular disease. Consequently, in the decade since its discovery, adiponectin has generated immense interest as a potential therapeutic target for the metabolic syndrome and diabetes.
This review summarizes current research regarding the regulation of circulating adiponectin concentrations by physiological, pharmacological, and nutritional factors, with an emphasis on human studies. In humans, plasma adiponectin concentrations are influenced by age and gender, and are inversely proportional to visceral adiposity. In vitro studies suggest that adiponectin production may be determined primarily by adipocyte size and insulin sensitivity, with larger, insulin-resistant adipocytes producing less adiponectin. While adiponectin concentrations are unchanged after meal ingestion, they are increased by significant weight loss, such as after bariatric surgery. In addition, adiponectin production is inhibited by a number of hormones, including testosterone, prolactin, glucocorticoids and growth hormone, and by inflammation and oxidative stress in adipose tissue. Smoking decreases, while moderate alcohol consumption increases, circulating adiponectin concentrations. Dietary fatty acid composition in rodents influences adiponectin production via ligand-activated nuclear receptors (PPARs); however, current evidence in humans is equivocal. In addition to PPAR agonists (such as thiazolidinediones and fibrates), a number of pharmacological agents (angiotensin receptor type 1 blockers, ACE inhibitors, and cannabinoid receptor antagonists) used in treatment of the metabolic syndrome also increase adiponectin concentrations in humans.
Despite generally lower socioeconomic status and worse access to healthcare, Latinos have better overall health outcomes and longer life expectancy than non-Latino Whites. This “Latino Health Paradox” has been partially attributed to healthier cardiovascular (CV) behaviors among Latinos. However, as Latinos become more acculturated, differences in some CV behaviors disappear. This study aimed to explore how associations between acculturation and CV behaviors among Latinos vary by country of origin. Combined weighted data from the 2005 and 2007 California Health Interview Survey (CHIS) were used to investigate associations between acculturation level and CV behaviors among Latinos by country of origin. Among all Latinos, increased acculturation was associated with more smoking, increased leisure-time physical activity, and greater consumption of fast foods, but no change in fruit/vegetable and less soda intake. These trends varied, however, by Latino sub-groups from different countries of origin. Country of origin appears to impact associations between acculturation and CV behaviors among Latinos in complex ways.
Acculturation Cardiovascular behaviors Latinos Country of origin
The prevalence rate of obesity in the United States has been persistently high in recent decades, and disparities in obesity risks are routinely observed. Both individual and contextual factors should be considered when addressing health disparities. This study examines how Latino-white spatial segregation is associated with the risk of obesity for Latinos and whites, whether neighborhood socioeconomic resources, the built environment, and subcultural orientation serve as the underlying mechanisms, and whether neighborhood context helps explain obesity disparities across ethnic and immigrant groups. The study was based on an extensive database containing self-reported BMI measures obtained from driver license records in Utah merged with census data and several GIS-based data. Multilevel analyses were performed to examine the research questions. For both men and women, Latino residential isolation is significantly and positively linked to the risk of obesity; after controlling for immigrant concentration, this effect gets amplified. Moreover, for men and women, the segregation effect is partly attributable to neighborhood SES and the built environment; and only for women is it partly attributable to obesity prevalence in the neighborhood. Place matters for individual risk of obesity for both men and women and there are multifarious pathways linking residence to obesity. Among the demographic, socioeconomic, physical, and cultural aspects of neighborhood context examined in this study, perhaps the most modifiable environment features that could prevent weight gain and its associated problems would be the built environmental factors such as greenness, park access, and mixed land use.
Obesity; Residential segregation; Immigrant enclave; Built environment
Striking decreases in colorectal cancer (CRC) incidence have been seen recently in non-Latino Whites but not in Latinos. The purpose of our study was to examine the influence of limited English proficiency (LEP) on differences in CRC test use rates between Mexican American and non-Latino White adults in California and reported reasons for not getting a CRC exam.
Cross-sectional analysis of the 2005 California Health Interview Survey (CHIS).
Representative sample of non-institutionalized adults living in California.
Mexican American (n=1,529) and non-Latino White men and women aged 50 and older (n=16,775) who had not been diagnosed with CRC.
Logistic regression analyzed the effect of ethnicity and limited English proficiency (LEP) on CRC test use after adjusting for sociodemographics, healthcare access, health status, and other health behaviors.
Main Outcome Measures
Respondents' likelihood of not receiving the CRC exam was examined as a function of ethnicity and LEP status; differences in reasons for not receiving CRC testing between ethnic groups were also examined.
More than 40% of Californian Mexican American adults aged 50 and older have never had either fecal occult blood test or lower endoscopy CRC tests. Mexican Americans were more likely to have difficulty understanding their doctor due to language barriers (P<.01). Mexican Americans more often reported provider barriers in getting an endoscopy (ie, test was not recommended by their medical provider) than non-Latino Whites (P=.01). After adjustment for covariates, Mexican Americans were 1.32 times and those with LEP were 1.68 times more likely to have never had either CRC test.
Limited English proficiency significantly decreased the likelihood of getting tested for CRC (P<.01). Eliminating language barriers should result in improvements in CRC test use among limited English proficiency Mexican Americans.
Mexican Americans; Colonoscopy; Colorectal Cancer; Screening
The aim of this study was to investigate sex differences and associations of high molecular weight (HMW) adiponectin, leptin and proinflammatory adipokines, individually or in combinations, with adiposity and insulin resistance (IR) measures in prepubertal childhood.
We studied 305 prepubertal children (boys/girls: 144/161; Tanner stage 1; age: 5-13 yr), included in a cohort of 44,231 adolescents who participated in an extensive Italian school-based survey. According to Cole's criteria, 105 individuals were lean (L; boys/girls: 59/46), 60 overweight (OW; boys/girls: 32/28) and 140 obese (OB; boys/girls: 70/70). Measurements comprised total and HMW adiponectin, leptin, as well as a panel of proinflammatory adipokines/chemokines associated with diabetes risk.
Leptin-, and the leptin-to-HMW adiponectin ratio (L/HMW)-, increased progressively (p<0.0001) from L to OW to OB boys and girls. When compared with L peers, OW and OB girls exhibited lower (p<0.001) HMW adiponectin levels, while in boys the HMW multimers did not differ significantly across the BMI-stratified groups. OB girls displayed higher (p<0.05) IL-8, IL-18, monocyte chemoattractant protein-1 (MCP-1) and soluble intercellular adhesion molecule-1 levels (sICAM-1) than L girls, whereas increased macrophage migration inhibitory factor (MIF) concentrations in OB vs OW boys were seen. HMW adiponectin (negatively), leptin or inflammatory markers (positively) correlated with adiposity and IR measures. In multivariate models, leptin represented a strong and independent determinant of HOMA-IR (R2 0.378; p<0.01). Adjustment for age, BMIz-score, lipids and inflammatory mediators abolished the association between leptin and HOMA-IR in boys, while in girls leptin remained still a significant predictor of IR (R2 0.513; p<0.01). Finally, in both sexes, the joint effect of the L/HMW did not improve the prediction of basal IR as compared with leptin levels alone, which were mainly explained by the BMIz-score.
In prepubertal children, leptin emerges as a sex-independent discrimination marker of adiposity degree and as a useful, sex-associated predictor of the systemic insulin resistance.
Abdominal obesity and insulin resistance (IR) place youth at higher risk for premature cardiovascular disease (CVD), but the underlying mechanisms are not clear. In adults, abdominal obesity and IR contribute to the oxidation of low-density lipoprotein (LDL). Whether similar mechanisms are operational in Latino adolescents is unknown. Therefore, we determined whether IR and abdominal adiposity are associated with higher oxLDL concentrations in Latino adolescents. Data from 123 Latino adolescents (16.3 ± 2.5 years; female = 74) were used for the present analysis. Participants were assessed for waist circumference, fasting serum oxLDL, and insulin sensitivity by the whole body insulin sensitivity index. In separate linear regression models adjusting for age and sex, both waist circumference and insulin sensitivity were significant predictors of oxLDL (β = 1.9; p = 0.002; R2 = 0.13, β = -1.7; p = 0.006; R2 = 0.11, respectively). When insulin sensitivity and waist circumference were included in the same model, both remained independent predictors of oxLDL (β = 1.7; p = 0.016 and, β = -1.5; p = 0.055, respectively; R2 = 0.16). These results suggest that insulin resistance and abdominal adiposity are associated with higher levels of LDL oxidation which may be a mechanism contributing to increased CVD risk in Latino adolescents.
Latino adolescents; Oxidized LDL; Abdominal obesity; Insulin resistance; Metabolic syndrome
This paper examines differences in cardiovascular disease risk factor control among racial/ethnic minorities (Asian Indian, Chinese, Filipino, Japanese, Korean, Vietnamese, Hispanic/Latino, Black/African Americans) with type 2 diabetes compared to Non-Hispanic Whites with type 2 diabetes in an insured, outpatient setting.
A three-year, cross-sectional sample of 15,826 patients with type 2 diabetes was studied between 2008 and 2010. Goal attainment rates for three cardiovascular disease risk factors (HbA1c, BP, LDL) were estimated. Logistic regression was used to determine the association between patient characteristics and control of risk factors.
Only one fifth (21.1%) of patients achieved simultaneous goal attainment (HbA1c, BP, LDL). After adjustment for patient characteristics and treatment, Black/African American women and men, and Filipino and Hispanic/Latino men were significantly less likely to simultaneously achieve all three goals, compared to Non-Hispanic Whites. Of the three goals, patients were more likely to achieve HbA1c goals (68.7%) than BP (45.7%) or LDL (58.5%) goals. Racial/ethnic differences were more apparent in risk factors that were under better control (i.e. HbA1c).
Cardiovascular risk factor control in type 2 diabetes is suboptimal, even in an insured population. Special attention may be required for specific racial/ethnic/gender groups.
Race/ethnicity; Primary prevention; Cardiovascular diseases; Disparities; Type 2 diabetes
Objective The goal of this study is to identify individual, family/cultural, and illness-related protective factors that may minimize asthma morbidity in the context of multiple urban risks in a sample of inner-city children and families. Methods Participating families are from African-American (33), Latino (51) and non-Latino white (47) backgrounds. A total of 131 children with asthma (56% male), ages 6–13 years and their primary caregivers were included. Results Analyses supported the relationship between cumulative risks and asthma morbidity across children of the sample. Protective processes functioned differently by ethnic group. For example, Latino families exhibited higher levels of family connectedness, and this was associated with lower levels of functional limitation due to asthma, in the context of risks. Conclusions This study demonstrates the utility of examining multilevel protective processes that may guard against urban risks factors to decrease morbidity. Intervention programs for families from specific ethnic groups can be tailored to consider individual, family-based/cultural and illness-related supports that decrease stress and enhance aspects of asthma treatment.
asthma outcomes; cultural factors; inner city; pediatric asthma; protective factors
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.
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.
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).
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.