Association between glycemic index and glycemic load and the risk of incident coronary heart disease among whites and African Americans with and without type 2 diabetes: The Atherosclerosis Risk in Communities study

Several studies have examined the association between high glycemic index (GI) and glycemic load (GL) diets and the risk for coronary heart disease (CHD). However, most of these studies were conducted primarily on white populations. The primary aim of this study was to examine whether high GI and GL diets are associated with increased risk for developing CHD in whites and African Americans, non-diabetics and diabetics, and within stratifications of body mass index (BMI) and hypertension (HTN). Baseline and 17-year follow-up data from ARIC (Atherosclerosis Risk in Communities) study was used. The study population (13,051) consisted of 74% whites, 26% African Americans, 89% non-diabetics, 11% diabetics, 43% male, 57% female aged 44 to 66 years at baseline. Data from the ARIC food frequency questionnaire at baseline were analyzed to provide GI and GL indices for each subject. Increases of 25 and 30 units for GI and GL respectively were used to describe relationships on incident CHD risk. Adjusted hazard ratios for propensity score with 95% confidence intervals (CI) were used to assess associations. During 17 years of follow-up (1987 to 2004), 1,683 cases of CHD was recorded. Glycemic index was associated with 2.12 fold (95% CI: 1.05, 4.30) increased incident CHD risk for all African Americans and GL was associated with 1.14 fold (95% CI: 1.04, 1.25) increased CHD risk for all whites. In addition, GL was also an important CHD risk factor for white non-diabetics (HR=1.59; 95% CI: 1.33, 1.90). Furthermore, within stratum of BMI 23.0 to 29.9 in non-diabetics, GI was associated with an increased hazard ratio of 11.99 (95% CI: 2.31, 62.18) for CHD in African Americans, and GL was associated with 1.23 fold (1.08, 1.39) increased CHD risk in whites. Body mass index modified the effect of GI and GL on CHD risk in all whites and white non-diabetics. For HTN, both systolic blood pressure and diastolic blood pressure modified the effect on GI and GL on CHD risk in all whites and African Americans, white and African American non-diabetics, and white diabetics. Further studies should examine other factors that could influence the effects of GI and GL on CHD risk, including dietary factors, physical activity, and diet-gene interactions. ^

A cross-sectional analysis of physical activity and obesity in inner city Houston Texas Mexican American youth

Obesity prevalence among children and adolescents is rising. It is one of the most attributable causes of hospitalization and death. Overweight and obese children are more likely to suffer from associated conditions such as hypertension, dyslipidemia, chronic inflammation, increased blood clotting tendency, endothelial dysfunction, hyperinsulinemia, and asthma. These children and adolescents are also more likely to be overweight and obese in adulthood. Interestingly, rates of obesity and overweight are not evenly distributed across racial and ethnic groups. Mexican American youth have higher rates of obesity and are at higher risk of becoming obese than non-Hispanic black and non-Hispanic white children. ^ Methods. This cross-sectional study describes the association between rates of obesity and physical activity in a sample of 1313 inner-city Mexican American children and adolescents (5-19 years of age) in Houston, Texas. This study is important because it will contribute to our understanding of childhood and adolescent obesity in this at-risk population. ^ Data from the Mexican American Feasibility Cohort using the Mano a Mano questionnaire are used to describe this population's status of obesity and physical activity. An initial sample taken from 5000 households in inner city Houston Texas was used as the baseline for this prospective cohort. The questionnaire was given in person to the participants to complete (or to parents for younger children) at a home visit by two specially trained bilingual interviewers. Analysis comprised prevalence estimates of obesity represented as percentile rank (<85%= normal weight, >85%= at risk, >95%= obese) by age and gender. The association between light, moderate, strenuous activity, and obesity was also examined using linear regression. ^ Results. Overall, 46% of this Mexican American Feasibility cohort is overweight or obese. The prevalence for children in the 6-11 age range (53.2%) was significantly greater than that reported from NHANES, 1999–2002 data (39.4%). Although the percentage of overweight and obese among the 12-19 year olds was greater than that reported in NHANES (38.5% versus 38.6%) this difference was not statistically significant. ^ A significant association between BMI and sit time and moderate physical activity (both p < 0.05) found in this sample. For males, this association was significant for moderate physical activity (p < 0.01). For the females, this association was significant for BMI and sit time (p < 0.05). These results need to be interpreted in the light of design and measurement limitations. ^ Conclusion. This study supports observations that the inner city Houston Texas Mexican American child and adolescent population is more overweight and obese than nationally reported figures, and that there are positive relationships between BMI, activity levels, and sit time in this population. This study supports the need for public health initiatives within the Houston Hispanic community. ^

Characterization of glucocorticoid receptor (NR3C1) gene polymorphisms and a family-based association study with hypertension

Hypertension is usually defined as having values of systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg. Hypertension is one of the main adverse effects of glucocorticoid on the cardiovascular system. Glucocorticoids are essential hormones, secreted from adrenal glands in circadian fashion. Glucocorticoid's effect on blood pressure is conveyed by the glucocorticoid receptor (NR3C1), an omnipresent nuclear transcription factor. Although polymorphisms in this gene have long been implicated to be a causal factor for cardiovascular diseases such as hypertension, no study has yet thoroughly interrogated the gene's polymorphisms for their effect on blood pressure levels. Therefore, I have first resequenced ∼30 kb of the gene, encompassing all exons, promoter regions, 5'/3' UTRs as well as at least 1.5 kb of the gene's flanking regions from 114 chromosome 5 monosomic cell lines, comprised of three major American ethnic groups—European American, African American and Mexican American. I observed 115 polymorphisms and 14 common molecularly phased haplotypes. A subset of markers was chosen for genotyping study populations of GENOA (Genetic Epidemiology Network of Atherosclerosis; 1022 non-Hispanic whites, 1228 African Americans and 954 Mexican Americans). Since these study populations include sibships, the family-based association test was performed on 4 blood pressure-related quantitative variables—pulse, systolic blood pressure, diastolic blood pressure and mean arterial pressure. Using these analyses, multiple correlated SNPs are significantly protective against high systolic blood pressure in non-Hispanic whites, which includes rsb198, a SNP formerly associated with beneficial body compositions. Haplotype association analysis also supports this finding and all p-values remained significant after permutation tests. I therefore conclude that multiple correlated SNPs on the gene may confer protection against high blood pressure in non-Hispanic whites. ^

The association of HSV 1 and 2 with atherosclerosis defined by CRP level

A study of the association of Herpes simplex virus 1 and 2 exposure to early atherosclerosis using high C-reactive protein level as a marker was carried out in US born, non-pregnant, 20-49 year olds participating in a national survey between 1999 and 2004. Participants were required to have valid results for Herpes simplex virus 1 and 2 and C-Reactive Protein for inclusion. Cases were those found to have a high C-reactive protein level of 0.3-1 mg/dL, while controls had low to normal values (0.01-0.29 mg/dL). Overall, there were 1211 cases and 2870 controls. Mexican American and non-Hispanic black women were much more likely to fall into the high cardiac risk group than the other sex race groups with proportions of 44% and 39%, respectively. ^ Herpesvirus exposure was categorized such that Herpes simplex virus 1 and 2 exposure could be studied simultaneously within the same individual and models. The HSV 1+, HSV 2- category included the highest percentage (45.63%) of participants, followed by HSV 1-, HSV 2- (30.16%); HSV 1+, HSV 2+ (15.09%); and HSV 1-, HSV 2+ (9.12%) respectively. The proportion of participants in the HSV 1+, HSV 2- category was substantially higher in Mexican Americans (63%-66%). Further, the proportion in the HSV 1+, HSV 2+ category was notably higher in the non-Hispanic black participants (23%-44%). Non-Hispanic black women also had the highest percentage of HSV 1-, HSV 2+ exposure of all the sex race groups at 17%. ^ Overall, the unadjusted odds ratios for atherosclerotic disease defined by C-reactive protein with HSV 1-, HSV 2- as the referent group was 1.62 (95% CI 1.23-2.14) for HSV 1 +, HSV 2+; 1.3 (95% CI 1.10-1.69 for HSV 1+, HSV 2-; and 1.52 (95% CI 1.14-2.01). When the study was stratified into sex-race groups, only HSV 1+, HSV 2- in the Non-Hispanic white men remained significant (OR=1.6; 95% CI 1.06-2.43). Adjustment for selected covariates was made in the multivariate model for both the overall and sex-race stratified studies. High C-reactive protein values were not associated with any of the Herpesvirus exposure levels in either the overall or stratified analyses. ^

Fruit and vegetable dietary patterns and weight loss in Mexican-American women

Although dietary patterns and their association with health outcomes is not a new topic, they have not been widely studied in Mexican-American populations. There are no studies of fruit and vegetable dietary patterns related to weight loss in Mexican-American women. This study aims to examine whether a change in proportion of fruit and vegetable consumption results in a change in weight. A secondary data analysis of 208 overweight or obese Mexican-American women from the Unidos en Salud weight loss intervention study was performed to investigate this relationship. Through regression analysis, the change in weight for every unit change in proportion of fruits and vegetables was tested with appropriate adjustment for age. The results showed a significant inverse association between fruit and vegetable intake densities and weight change. These results support previous studies and provide a possible effective and efficient method to reduce body mass index (BMI) among overweight or obese Mexican-American women. ^

The association between diabetes and hepatitis C: A systematic review of epidemiological evidence

Background. Several studies have proposed a link between type 2 Diabetes mellitus (DM2) and Hepatitis C infection (HCV) with conflicting results. Since DM2 and HCV have high prevalence, establishing a link between the two may guide further studies aimed at DM2 prevention. A systematic review was conducted to estimate the magnitude and direction of association between DM2 and HCV. Temporality was assessed from cohort studies and case-control studies where such information was available. ^ Methods. MEDLINE searches were conducted for studies that provided risk estimates and fulfill criteria regarding the definition of exposure (HCV) and outcomes (DM2). HCV was defined in terms of method of diagnosis, laboratory technique and method of data collection; DM2 was defined in terms of the classification [World Health Organization (WHO) and American Diabetes Association (ADA)] 1-3 used for diagnosis, laboratory technique and method of data collection. Standardized searches and data abstraction for construction of tables was performed. Unadjusted or adjusted measures of association for individual studies were obtained or calculated from the full text of the studies. Template designed by Dr. David Ramsey. ^ Results. Forty-six studies out of one hundred and nine potentially eligible articles finally met the inclusion and exclusion criteria and were classified separately based on the study design as cross-sectional (twenty four), case-control (fifteen) or cohort studies (seven). The cohort studies showed a three-fold high (confidence interval 1.66–6.29) occurrence of DM2 in individuals with HCV compared to those who were unexposed to HCV and cross sectional studies had a summary odds ratio of 2.53 (1.96, 3.25). In case control studies, the summary odds ratio for studies done in subjects with DM2 was 3.61 (1.93, 6.74); in HCV, it was 2.30 (1.56, 3.38); and all fifteen studies, together, yielded an odds ratio of 2.60 (1.82, 3.73). ^ Conclusion. The above results support the hypothesis that there is an association between DM and HCV. The temporal relationship evident from cohort studies and proposed pathogenic mechanisms also suggest that HCV predisposes patients to development of DM2. Further cohort or prospective studies are needed, however, to determine whether treatment of HCV infections prevents development of DM2.^

Antiretroviral therapy adherence and the use of condoms among African American HIV-positive crack cocaine users

Safer sex practices, such as consistent condom use, are essential to reduce HIV transmission. Determining causes and/or co-variants related to the likelihood of participating in high-risk sexual behaviors may allow the content of interventions and treatments to minimize HIV transmission to be tailored more effectively. The goal of this study was to examine whether a relationship exists between consistent condom use among African American HIV-positive crack cocaine users and both (1) the use of antiretroviral therapy, and (2) adherence to antiretroviral therapy regimens. The study population consisted of 390 participants. They were at least 18 years old, African American, HIV-positive, and had used crack cocaine within a month prior to an interview conducted sometime between April, 2004, and September, 2007. Bivariate associations were examined using contingency tables and χ2-statistics. The Mantel-Haenszel method was used to control for confounding. This study found neither a significant relationship between use of antiretroviral therapy and consistent condom use (Odds ratio (OR) = 1.38; 95% Confidence interval (95%CI) = 0.86–2.22), nor an association between antiretroviral therapy adherence and consistent condom use (OR = 1.02, 95%CI = 0.60–1.75). The exception was more consistent condom use when sex was traded for money or drugs in those on antiretroviral therapy, compared to those not on such therapy (OR = 2.28, 95%CI = 1.08–4.85). Further studies examining condom use and HIV treatment adherence are recommended. ^

Association of self-reported physical activity and performance in the physical fitness assessment among Airmen

The U.S. Air Force, as with the other branches of military services, has physical fitness standards imposed on their personnel. These standards ensure a healthy and fit combat force. To meet these standards, Airmen have to maintain a certain level of physical activity in their lifestyle. Objective. This was a cross sectional (prevalence) study to evaluate the association of Airmen's self-reported physical activity and their performance in the Air Force Physical Fitness Assessment in 2007. Methods. The self-reported physical activity data were obtained from the Air Force Web Health Assessment (AF WEB HA), a web-based health questionnaire completed by the Airmen during their annual Preventive Health Assessment. The physical activity levels were categorized as having met or not having met the Centers for Disease Control and Prevention (CDC) and the American College of Sports Medicine (ACSM) physical activity recommendations. Physical Fitness scores were collected from the Air Force Fitness Management System (AFFMS), a repository of physical fitness test data. Results. There were 49,029 Airmen who answered the AF WEB HA in 2007 and also took their physical fitness test. 94.4% (n = 46,304) of Airmen met the recommended physical activity guidelines and 79.9% (n = 39,178) passed the fitness test. Total Airmen who both met the physical activity recommendations and passed the fitness test was 75.6% (n = 37,088). Airmen who did not meet the activity recommendations and also failed the fitness test totaled 635 or 1.3% of the study group. The Mantel-Haenszel Chi-Square analysis of the data on the activity levels and the physical fitness test relationship was the following χ2 = 18.52, df 1, and p = <0.0001. The Odds Ratio (OR) was 1.22 (95% CI 1.12, 1.34). Conclusion. The study determined that there was a positive association between Airmen's self-reported physical activity and their performance in the physical fitness assessment.^

The association of peer victimization and/or bullying perpetration and body dissatisfaction in elementary students from the healthy passages baseline study

This is the first U.S. study to investigate the association between peer victimization and/or bullying perpetration and body image dissatisfaction in American elementary school students. The study used data collected from the Healthy Passages baseline cohort of 5152 ethnically diverse fifth grade students from Alabama, Texas, and California. The overall prevalence of body dissatisfaction in our fifth grade sample was 50%. Students who were dissatisfied with their bodies were 23% more likely to be involved in peer victimization than students who were satisfied with their bodies (OR = 1.23; 95% CI = 1.02, 1.48). No significant associations were found between bullying status or bully-victim status and body dissatisfaction. Other factors that contributed significantly to a student's body image status were BMI, level of self-worth, level of household income, gender, pubertal timing and support received from adults (other than parents). It is noteworthy that those who were dissatisfied were heavier, came from lower income homes and were more likely to be male. Additional longitudinal studies are needed to confirm these associations, especially among large ethnically and socio-economically diverse samples. ^

The association between mental health and hypertension in the 2005 Department of Defense Population Survey

Major objectives within Healthy People 2010 include improving hypertension and mental health management of the American population. Both mental health issues and hypertension exist in the military which may decrease the health status of military personnel and diminish the ability to complete assigned missions. Some cases may be incompatible with military service even with optimum treatment. In the interest of maintaining a fit fighting force, the Department of Defense regularly conducts a survey of health related behaviors among active duty military personnel. The 2005 DoD Survey was conducted to obtain information regarding health and behavioral readiness among active duty military personnel to assess progress toward selected Healthy People 2010 objectives. ^ This study is a cross-sectional prevalence design looking at the association of hypertension treatment with mental health issues (either treatment or perceived need for treatment) within the military population sampled in the 2005 DoD Survey. There were 16,946 military personnel in the final cross-sectional sample representing 1.3 million active duty service members. The question is whether there is a significant association between the self-reported occurrence of hypertension and the self-reported occurrence of mental health issues in the 2005 DoD Survey. In addition to these variables, this survey examined the contribution of various sociodemographic, occupational, and behavioral covariates. An analysis of the demographic composition of the study variables was followed by logistic analysis, comparing outcome variables with each of the independent variables. Following univariate regression analysis, multivariate regression was performed with adjustment (for those variables with an unadjusted alpha level less than or equal to 0.25). ^ All the mental health related indicators were associated with hypertension treatment. The same relationship was maintained after multivariate adjustment. The covariates remaining as significant (p < 0.05) in the final model included gender, age, race/ethnicity and obesity. There is a need to recognize and treat co-morbid medical diagnoses among mental health patients and to improve quality of life outcomes, whether in the military population or the general population. Optimum health of the individual can be facilitated through discovery of treatable cases, to minimize disruptions of military missions, and even allow for continued military service. ^

Social cognitive theory and factors associated with Mexican-American parents' beliefs, attitudes and practices regarding communication with their adolescent children about sex

Latinos have the highest teen birth rate nationally. Cameron County, Texas is primarily Latino (Mexican-American). This mixed-method study (n=43) examines Mexican-American parents of adolescents' beliefs, attitudes and practices regarding communication with their adolescent children about sex. Social Cognitive Theory (SCT) constructs self-efficacy, behavioral determinism, environment, outcome expectations and reciprocal determinism can be influences on frequency and quality of parent-adolescent sex communication.^ This study describes Mexican-American parents' of adolescents recollections of their own experiences associated with learning about sexuality. It also examines the attitudes and practices regarding communication about sex and the self-efficacy and behavioral capability of participants to teach their adolescent children about sex and sexually transmitted infections. ^ Negative childhood experiences (shame, lies and trauma) of the parents in this study played a key role in terms of their desire to communicate more comprehensively about sexuality with their own children than did their parents. While participants' reported low self-efficacy and behavioral capability to communicate with their adolescent children about sex, they reported relatively high frequency and quality of communication, with 75% of participants receiving a high quality score and over 44% reporting frequent communication with their adolescent children about sex. A Chi square analysis and Fisher's Exact Score revealed no association between acculturation status, gender or having a child who has mothered/fathered a baby and the frequency or quality of communication about sex with adolescent children. Study participants also gave specific recommendations for method, content and setting of sex education for their children and themselves. Promotora delivery of information and education in a comfortable, culturally appropriate neighborhood setting, as well as parent –child learning sessions were identified as possible approaches to address improve self-efficacy and behavioral capability of parents communicating with their adolescent children about sex.^ The results of this analysis provide public health practitioners and interested community entities data to identify and develop interventions that use a theoretical, evidence-based framework for culturally appropriate interventions to encourage and equip Mexican-American parents to effectively communicate with their adolescent children about sexuality, and ultimately to address the high rates of teen pregnancy in this U.S.-Mexico border community. ^

The effect of obesity on mammography utilization in African American women

Breast cancer continues to reign as a common cause of death for women in the United States, claiming the lives of more than an estimated 40,000 women in 2009 alone (Ries et al., 2009). A mammogram, an x-ray of the breast, can aid in early detection of breast cancer and thus more successful treatment. Screening patterns indicate African American women are less likely to utilize mammography technology when compared to their Caucasian counterparts. Additionally, the obesity epidemic in the United States remains a major public health problem. Obesity trends indicate that African American women are likely to be more obese when compared to Caucasian women. Pischon, Nöthlings, & Boeing (2008) concluded there was sufficient evidence linking breast cancer and obesity. Many researchers have identified obesity as a risk factor for breast cancer. As African American women are disproportionately burdened by both breast cancer mortality and obesity, more extensive research is needed to gain more knowledge about their association. The purpose of this study was to identify the role obesity plays in lessening an African American woman’s usage of mammography technology. Data from the 2005 National Health Interview Study were analyzed using SPSS to evaluate the relationship between body mass index (BMI) and mammography utilization in the two aforementioned populations.^ After excluding respondents from the sample who did not meet the set criteria, there were 17,666 women remaining. Of the 17,666 women, 6,156 (34.8%) had a healthy weight, 6,024 (34.1%) were overweight, and 4,285 (24.3%) were obese. About 70% of the sample population reported having had a mammogram in the last two years. Another 27.6% of women reported not receiving a mammogram within this same two year time frame. Within ethnic categories, the majority of the sample was Caucasian (64.2%) while only 15.1% of the sample was African American. The relationship between mammography usage and body mass index was not statistically significant within any body mass index categories. When analyzing the relationship between mammography usage and BMI, adjusting for ethnicity, there was also no significant difference between obese African American and obese Caucasian women. The study did find significant relationships between mammography usage and body mass index when adjusting for cancer risk OR = .79 (95% CI .72 - .85), and marital status OR = 1.18 (95% CI 1.05 - 1.34). Due to insignificant findings, there was no evidence to support the hypothesis regarding differences in mammography usage based on weight or ethnicity. Mammography screening differences based on ethnicity are widely cited. Unfortunately it is still unclear exactly where these differences lie. Obesity has been widely documented in the literature as a risk factor for many chronic diseases, including certain forms of cancer. Understanding the relationship between screening behaviors and weight can assist in the development of health promotion programs aimed at high risk groups. In order to change screening behavior and reduce mortality from breast cancer, more research is needed to identify similarities within low screening populations.^

Association of exogenous hormonal intake with the risk of development of hepatocellular carcinoma in women

Background. Primary liver cancer, the majority of which is hepatocellular carcinoma, is the third most common cause of mortality from cancer. It has one of the worst prognosis outcomes and an overall 5-year survival of only 5-6%. Hepatocellular carcinoma has been shown to have wide variations in geographic distribution and there is a marked difference in the incidence between different races and gender. Previously low-rate countries, including the US, have shown to have doubled the incidence of HCC during the past two decades. Even though the incidence of HCC is higher in males as compared to females, female hormones, especially estrogens have been postulated to have a role in the development of hepatocellular carcinoma on a molecular level. Despite the frequent usage of oral contraceptive pills (OCP) and previously, hormone replacement therapy (HRT), their role on HCC development has not been studied thoroughly. We aim to examine the association between exogenous hormone intake (oral contraceptives and post-menopausal hormone replacement therapy) and the development of HCC. Methods. This study is part of an ongoing hospital-based case-control study which is conducted at the Department of Gastrointestinal Oncology at The University of Texas M. D. Anderson Cancer Center. From January 2005 up to January 2008, a total of 77 women with pathologically confirmed hepatocellular carcinoma (cases) and 277 healthy women (controls) were included in the investigation. Information about the use of hormonal contraceptives, hormone replacement therapy and risk factors of hepatocellular cancer was collected by personal interview. Univariate and multivariate logistic regression analyses were done to estimate the crude odds ratios (OR) and adjusted odds ratios (AOR). Results. We found statistically significant protective effect for the use of HRT on the development of HCC, AOR=0.42 (95% CI, 0.21, 0.81). The significance was observed for estrogen replacement, AOR=0.43 (95% CI, 0.22, 0.83) and not for progesterone replacement, AOR=0.49 (95% CI, 0.10, 2.35). On the other hand, any hormonal contraceptive use, which encompasses oral contraceptive pills, implants and injections, did not show a statistical significance either in the crude OR=0.58 (95% CI, 0.33, 1.01) or AOR=0.56 (95% CI 0.26, 1.18). Conclusions. As corroborated by previous studies, HRT confers 58% HCC risk reduction among American women. The more important question of the association between hormonal contraceptives and HCC remains controversial. Further studies are warranted to explore the mechanism of the protective effect of HRT and the relationship between hormonal contraception and HCC.^

Genome-wide association study of LDL-cholesterol over ApoB ratio

Genome-Wide Association Study analytical (GWAS) methods were applied in a large biracial sample of individuals to investigate variation across the genome for its association with a surrogate low-density lipoprotein (LDL) particle size phenotype, the ratio of LDL-cholesterol level over ApoB level. Genotyping was performed on the Affymetrix 6.0 GeneChip with approximately one million single nucleotide polymorphisms (SNPs). The ratio of LDL cholesterol to ApoB was calculated, and association tests used multivariable linear regression analysis with an additive genetic model after adjustment for the covariates sex, age and BMI. Association tests were performed separately in African Americans and Caucasians. There were 9,562 qualified individuals in the Caucasian group and 3,015 qualified individuals in the African American group. Overall, in Caucasians two statistically significant loci were identified as being associated with the ratio of LDL-cholesterol over ApoB: rs10488699 (p<5 x10-8, 11q23.3 near BUD13) and the SNP rs964184 (p<5 x10-8 11q23.3 near ZNF259). We also found rs12286037 ((p<4x10-7) (11q23.3) near APOA5/A4/C3/A1 with suggestive associate in the Caucasian sample. In exploratory analyses, a difference in the pattern of association between individuals taking and not taking LDL-cholesterol lowering medications was observed. Individuals who were not taking medications had smaller p-value than those taking medication. In the African-American group, there were no significant (p<5x10-8) or suggestive associations (p<4x10-7) with the ratio of LDL-cholesterol over ApoB after adjusting for age, BMI, and sex and comparing individuals with and without LDL-cholesterol lowering medication. Conclusions: There were significant and suggestive associations between SNP genotype and the ratio of LDL-cholesterol to ApoB in Caucasians, but these associations may be modified by medication treatment.^

A GENETIC MARKER STUDY OF NON - INSULIN DEPENDENT DIABETICS IN THE MEXICAN-AMERICAN COMMUNITY FROM STARR COUNTY, TEXAS (PLASMA GLUCOSE, HEMOGLOBIN ANALYSIS)

Diabetes mellitus occurs in two forms, insulin-dependent (IDDM, formerly called juvenile type) and non-insulin dependent (NIDDM, formerly called adult type). Prevalence figures from around the world for NIDDM, show that all societies and all races are affected; although uncommon in some populations (.4%), it is common (10%) or very common (40%) in others (Tables 1 and 2).^ In Mexican-Americans in particular, the prevalence rates (7-10%) are intermediate to those in Caucasians (1-2%) and Amerindians (35%). Information about the distribution of the disease and identification of high risk groups for developing glucose intolerance or its vascular manifestations by the study of genetic markers will help to clarify and solve some of the problems from the public health and the genetic point of view.^ This research was designed to examine two general areas in relation to NIDDM. The first aims to determine the prevalence of polymorphic genetic markers in two groups distinguished by the presence or absence of diabetes and to observe if there are any genetic marker-disease association (univariate analysis using two by two tables and logistic regression to study the individual and joint effects of the different variables). The second deals with the effect of genetic differences on the variation in fasting plasma glucose and percent glycosylated hemoglobin (HbAl) (analysis of Covariance for each marker, using age and sex as covariates).^ The results from the first analysis were not statistically significant at the corrected p value of 0.003 given the number of tests that were performed. From the analysis of covariance of all the markers studied, only Duffy and Phosphoglucomutase were statistically significant but poor predictors, given that the amount they explain in terms of variation in glycosylated hemoglobin is very small.^ Trying to determine the polygenic component of chronic disease is not an easy task. This study confirms the fact that a larger and random or representative sample is needed to be able to detect differences in the prevalence of a marker for association studies and in the genetic contribution to the variation in glucose and glycosylated hemoglobin. The importance that ethnic homogeneity in the groups studied and standardization in the methodology will have on the results has been stressed. ^