A survey of statural changes with age in the adult population of the United States

A study of the patterns of height loss with age in the Anglo, black, and Mexican-American populations of the United States has been undertaken. The study was based on data gathered by the United States Public Health Service in the Second National Health and Nutrition Examination Survey and the Hispanic Health and Nutrition Examination Survey. Estimates of height loss were obtained by subtracting present stature from a calculated maximum attained height derived from sex- and race/ethnic-specific regression equations relating stature to subischial length. Anglo women have greater height losses than Anglo, black, or Mexican-American males, and black or Mexican-American females. Between 24 and 74 years of age, Anglo women average 3.8 cm. loss in stature. The black populations lose less height than Anglos or Mexican-Americans. Mexican-Americans lose less height than Anglos from 24 to 54 years and then have a greatly increased height loss so that by age 74 their total height loss is the same as Anglos. Standing height, sitting height, body mass index, and the Poverty Index were found to be negatively correlated with height loss. Age was positively correlated to height loss. The most important determinants of the magnitude of height loss with age were sex and ethnicity. ^

The prevalence, health risks, and consequences of asthma among adult residents in Texas

Based on asthma prevalence data collected from the 2000 BRFSS survey, approximately 14.7 million U.S. adults had current asthma, accounting for 7.2% of the total U.S. population. In Texas alone, state data extrapolated from the 1999-2003 Texas BRFSS suggested that approximately 1 million Texas adults were reporting current asthma and approximately 11% of the adult population has been diagnosed with the illness during their lifetime. From a public health perspective, the disease is manageable. Comprehensive state-specific asthma surveillance data are necessary to identify disparities in asthma prevalence and asthma-control characteristics among subpopulations and to develop targeted public health interventions. The purpose of this study was to determine the relative importance of various risk factors of asthma and to examine the impact of asthma on health-related quality of life among adult residents of Texas. ^ The study employed a cross-sectional study of respondents in Texas. The study extracted all the variables related to asthma along with their associated demographic, socioeconomic, and quality of life variables from the 2007 BRFSS data for 17,248 adult residents of Texas aged 18 and older. Chi-square test and logistic regression using SPSS were used in various data analyses on weighted data, adjusting for the complex sample design of the BRFSS data. All chi-square analyses were carried out using SPSS's CSTABULATE command. In addition, logistic regression models were fitted using SPSS's CSLOGISTIC command. ^ Risks factors significantly associated with reporting current asthma included BMI, race/ethnicity, gender, and income. Holding all other variables constant, obese adults were almost twice as likely to report current asthma as those adults who were normal weight (odds ratio [OR], 1.78; 95% confidence interval [CI], 1.25 to 2.53). Other non-Hispanic adults were significantly more likely to report current asthma than non-Hispanic Whites (OR, 2.43; 95% CI, 1.38 to 4.25), while Hispanics were significantly less likely to report current asthma than non-Hispanic Whites (OR, 0.38; 95% CI, 0.25 to 0.60), after controlling for all other variables. After adjusting for all other variables, adult females were almost twice as likely to report current asthma as males (OR, 1.97; 95% CI, 1.49 to 2.60). Adults with household income of less than $15,000 were almost twice as likely to report current asthma as those persons with an annual household income of $50,000 or more (OR, 1.98; 95% CI, 1.33 to 2.94). In regards to the association between asthma and health-related quality of life, after adjusting for age, race/ethnicity, gender, tobacco use, body mass index (BMI), exercise, education, and income, adults with current asthma compared to those without asthma were more likely to report having more than 15 days of unhealthy physical health (OR, 1.84; 95% CI, 1.29 to 2.60). ^ Overall, the findings of this study provide insight and valuable information into the populations in Texas most adversely affected by asthma and health-related consequences of the disease condition. Further research could build on the findings of this study by replicating this study as closely as possible in other asthma settings, and look at the relationship for hospitalization rates, asthma severity, and mortality.^

Evaluation of risk factors for long term changes in refractive error among adult patients at a Dallas Texas private setting A retrospective chart-review study

Background. Over 39.9% of the adult population forty or older in the United States has refractive error, little is known about the etiology of this condition and associated risk factors and their entailed mechanism due to the paucity of data regarding the changes of refractive error for the adult population over time.^ Aim. To evaluate risk factors over a long term, 5-year period, in refractive error changes among persons 43 or older by testing the hypothesis that age, gender, systemic diseases, nuclear sclerosis and baseline refractive errors are all significantly associated with refractive errors changes in patients at a Dallas, Texas private optometric office.^ Methods. A retrospective chart review of subjective refraction, eye health, and self-report health history was done on patients at a private optometric office who were 43 or older in 2000 who had eye examinations both in 2000 and 2005. Aphakic and pseudophakic eyes were excluded as well as eyes with best corrected Snellen visual acuity of 20/40 and worse. After exclusions, refraction was obtained on 114 right eyes and 114 left eyes. Spherical equivalent (sum of sphere + ½ cylinder) was used as the measure of refractive error.^ Results. Similar changes in refractive error were observed for the two eyes. The 5-year change in spherical power was in a hyperopic direction for younger age groups and in a myopic direction for older subjects, P<0.0001. The gender-adjusted mean change in refractive error in right eyes of persons aged 43 to 54, 55 to 64, 65 to 74, and 75 or older at baseline was +0.43D, +0.46 D, -0.09 D, and -0.23D, respectively. Refractive change was strongly related to baseline nuclear cataract severity; grades 4 to 5 were associated with a myopic shift (-0.38 D, P< 0.0001). The mean age-adjusted change in refraction was +0.27 D for hyperopic eyes, +0.56 D for emmetropic eyes, and +0.26 D for myopic eyes.^ Conclusions. This report has documented refractive error changes in an older population and confirmed reported trends of a hyperopic shift before age 65 and a myopic shift thereafter associated with the development of nuclear cataract.^

Genes to blood pressure: The effects of variation in genes of the renin-angiotensin system on the hormonal and renal control of blood pressure

Objective. Essential hypertension affects 25% of the US adult population and is a leading contributor to morbidity and mortality. Because BP is a multifactorial phenotype that resists simple genetic analysis, intermediate phenotypes within the complex network of BP regulatory systems may be more accessible to genetic dissection. The Renin-Angiotensin System (RAS) is known to influence intermediate and long-term blood pressure regulation through alterations in vascular tone and renal sodium and fluid resorption. This dissertation examines associations between renin (REN), angiotensinogen (AGT), angiotensin-converting enzyme (ACE) and angiotensin II type 1 receptor (AT1) gene variation and interindividual differences in plasma hormone levels, renal hemodynamics, and BP homeostasis.^ Methods. A total of 150 unrelated men and 150 unrelated women, between 20.0 and 49.9 years of age and free of acute or chronic illness except for a history of hypertension (11 men and 7 women, all off medications), were studied after one week on a controlled sodium diet. RAS plasma hormone levels, renal hemodynamics and BP were determined prior to and during angiotensin II (Ang II) infusion. Individuals were genotyped by PCR for a variable number tandem repeat (VNTR) polymorphism in REN, and for the following restriction fragment length polymorphisms (RFLP): AGT M235T, ACE I/D, and AT1 A1166C. Associations between clinical measurements and allelic variation were examined using multiple linear regression statistical models.^ Results. Women homozygous for the AT1 1166C allele demonstrated higher intracellular levels of sodium (p = 0.044). Men homozygous for the AGT T235 allele demonstrated a blunted decrement in renal plasma flow in response to Ang II infusion (p = 0.0002). There were no significant associations between RAS gene variation and interindividual variation in RAS plasma hormone levels or BP.^ Conclusions. Rather than identifying new BP controlling genes or alleles, the study paradigm employed in this thesis (i.e., measured genes, controlled environments and interventions) may provide mechanistic insight into how candidate genes affect BP homeostasis. ^

Predictors of weight stability in women and men: The aerobic center longitudinal study, 1987--1995

It is estimated that more than half the U.S. adult population is overweight or obese as classified by a body mass index of 25.0–29.9 or ≥30 kg/m 2, respectively. Since the current treatment approaches for long-term maintenance of weight loss are lacking, the National Institutes of Health state that an effective approach may be to focus on weight gain prevention. There is a limited body of literature describing how adults maintain a stable weight as they age. It is hypothesized that weight stability is the result of a balance between energy consumption and energy expenditure as influenced by diet, lifestyle, behavior, genetics and environment. The purpose of this research was to examine the dietary intake and behaviors, lifestyle habits, and risk factors for weight change that predict weight stability in a cohort of 2101 men and 389 women aged 20 to 8 7 years in the Aerobic Center Longitudinal Study regardless of body weight at baseline. At baseline, participants completed a maximal exercise treadmill test to determine cardiorespiratory fitness, a medical history questionnaire, which included self-reported measures of weight, dietary behaviors, lifestyle habits, and risk factors for weight change, a three-day diet record, and a mail-back version of the medical history questionnaire in 1990 or 1995. All analyses were performed separately for men and women. Results from multivariate regression analyses indicated that the strongest predictor of follow-up weight for men and women was previous weight, accounting for 87.0% and 81.9% of the variance, respectively. Age, length of follow-up and eating habits were also significant predictors of follow-up weight in men, though these variables only explained 3% of the variance. For women, length of follow-up and currently being on a diet were significantly associated with follow-up weight but these variables explained only an additional 2% of the variance. Understanding the factors that influence weight change has tremendous public health importance for developing effective methods to prevent weight gain. Since current weight was the strongest predictor of previous weight, preventing initial weight gain by maintaining a stable weight may be the most effective method to combat the increasing prevalence of overweight and obesity. ^

The epidemiology of Hepatitis B and Hepatitis C virus infection among college students who are not US/Canadian born in Houston

Introduction. A vast majority of studies conducted in both developed and developing nations have focused on the epidemiology of HBV (Hepatitis B virus) and HCV (Hepatitis C virus) in high-risk populations; low-risk populations have been neglected. Recently Hwang et al conducted a unique large cross-sectional study in American university students that focused on cosmetic procedures and drug use for acquiring these infections among a low-risk young adult population In Houston. ^ Methods. This study is a secondary data analysis of the cross-sectional study conducted by Hwang et al. Data for this anonymous study were collected from 7,960 college students, among whom were the 2,561 non US/Canadian born students included in this study. All students completed a self-administered questionnaire and provided a blood sample. The epidemiology of HBV/HCV and risk factors for acquiring HBV/HCV infection was studied by comparing those with HBV/HCV infection versus those without. Both univariate and multivariate logistic regression was used to analyze the data. ^ Results. Overall prevalence of HBV and HCV infections were 22% and 0.8% respectively. By multivariable analysis, the factors that were independently associated with increased prevalence of HBV infection were increasing age per year (OR=1.06, 95% C.I=1.04-1.08), Black or Asian race (OR=6.21, 95% C.I=3.14-12.27), history of household contact with hepatitis (OR=1.87, 95% C.I=1.15-3.05), and having sexual partner with hepatitis (OR=5.20, 95% C.I=1.5-18.00). For HCV these factors included increasing age per year (OR= 1.08, 95% C.I=1.03-1.14), history of blood transfusion prior to 1991 (OR=25.45, 95% C.I=7.58-85.40), and Injection drug use. (OR=78.15, 95% C.I=12.19-500.85). Cosmetic procedures like tattooing were not significant risk factors for either HBV or HCV infection. ^ Conclusions. In a low-risk adult foreign born population, cosmetic procedures are not significant risk factors for HBV or HCV infection. The prevention strategies of these infections in this population should focus on safe sexual practices/abstinence and HBV vaccination should be provided to adolescents and sexually active adults. ^

Comparison of compliance and immune response of drug users on the standard and accelerated hepatitis B vaccine schedules - Houston, Texas

Despite the availability of hepatitis B vaccine for over two decades, drug users and other high-risk adult populations have experienced low vaccine coverage. Poor compliance has limited efforts to reduce transmission of hepatitis B infection in this population. Evidence suggests that immunological response in drug users is impaired compared to the general population, both in terms of lower seroprotection rates and antibodies levels.^ The current study investigated the effectiveness of the multi-dose hepatitis B vaccine and compared the effect of the standard and accelerated vaccine schedules in a not-in-treatment, drug-using adult population in the city of Houston, USA.^ A population of drug-users from two communities in Houston, susceptible to hepatitis B, was sampled by outreach workers and referral methodology. Subjects were randomized either to the standard hepatitis vaccine schedule (0, 1-, 6-month) or to an accelerated schedule (0, 1-, 2-month). Antibody levels were detected through laboratory analyses at various time-points. The participants were followed for two years and seroconversion rates were calculated to determine immune response.^ A four percent difference in the overall compliance rate was observed between the standard (73%) and accelerated schedules (77%). Logistic regression analyses showed that drug users living on the streets were twice as likely to not complete all three vaccine doses (p=0.028), and current speedball use was also associated with non-completion (p=0.002). Completion of all three vaccinations in the multivariate analysis was also correlated with older age. Drug users on the accelerated schedule were 26% more likely to achieve completion, although this factor was marginally significant (p=0.085).^ Cumulative adequate protective response was gained by 65% of the HBV susceptible subgroup by 12-months and was identical for both the standard and accelerated schedules. Excess protective response (>=100 mIU/mL) occurred with greater frequency at the later period for the standard schedule (36% at 12-months compared to 14% at six months), while the greater proportion of excess protective response for the accelerated schedule occurred earlier (34% at 6 months compared to 18% at 12-months). Seroconversion at the adequate protective response level of 10 mIU/mL was reached by the accelerated schedule group at a quicker rate (62% vs. 49%), and with a higher mean titer (104.8 vs. 64.3 mIU/mL), when measured at six months. Multivariate analyses indicated a 63% increased risk of non-response for older age and confirmed the existence of an accelerating decline in immune response to vaccination manifesting after 40 years (p=0.001). Injecting more than daily was also highly associated with the risk of non-response (p=0.016).^ The substantial increase in the seroprotection rate at six months may be worth the trade-off against the faster antibody titer decrease and is recommended for enhancing compliance and seroconversion. Utilization of the accelerated schedule with the primary objective of increasing compliance and seroconversion rates during the six months after the first dose may confer early protective immunity and reduce the HBV vulnerability of drug users who continue, or have recently initiated, increased high risk drug use and sexual behaviors.^

Validating the dietary intake questions from the Tu Salud, ¡Si Cuenta! questionnaire

Background. Poor nutrition is an important factor in the onset of obesity which is a growing problem in the United States that disproportionately affects Mexican-Americans. In order to form recommendations and effectively target nutrition in interventions it is necessary to have valid epidemiological tools to better understand dietary trends. Purpose. The purpose of this study is to evaluate the validity of the nutritional intake questions from the Tu Salud, ¡Sí Cuenta! Questionnaire in an adult Mexican-American population. Methods. Fifty participants in the Cameron County Hispanic Cohort were recruited into the validity study, which consisted of completing the Tu Salud, ¡Sí Cuenta! questionnaire and the 24-hour recall with a 2 hour time period between administrations. Responses were analyzed to determine the percent agreement, kappa statistic and Spearman rank order correlation. Results: Five items had good validity (>0.6), three items had fair validity (>0.4), and three items had poor validity (<0.4). In general, items that had low validity were those that were reported in low frequencies by study subjects. Overall, the Tu Salud, ¡Sí Cuenta! questionnaire showed good validity, making this questionnaire a valuable tool to assess the dietary intake patterns of this Mexican-American adult population. ^

The economic cost of type 2 diabetes attributable to physical inactivity in the United States and Texas in 2007

Type 2 diabetes has grown to epidemic proportions in the U.S., and its prevalence has been steadily increasing in Texas. The physical activity levels in the population have remained low despite it being one of the primary preventive strategies for type 2 diabetes. The objectives of this study were to estimate the direct medical costs of type 2 diabetes attributable to not meeting physical activity Guidelines and to physical inactivity in the U.S. and Texas in 2007. This was a cross sectional study that used physical activity prevalence data from the 2007 Behavioral Risk Factor Surveillance System (BRFSS) to estimate the population attributable risk percentage (PAR%) for type 2 diabetes. These data were combined with the prevalence and cost data of type 2 diabetes to estimate the cost of type 2 diabetes attributable to not meeting Guidelines and to inactivity in the U.S. and Texas in 2007.^ The cost of type 2 diabetes in the U.S. in 2007, attributable to not meeting physical activity Guidelines was estimated to be $13.29 billion, and that attributable to physical inactivity (no leisure time physical activity) was estimated to be $3.32 billion. Depending on various assumptions, these estimates ranged from $7.61 billion to $41.48 billion for not meeting Guidelines, and $1.90 billion to $13.20 billion for physical inactivity in the U.S. in 2007. The cost of type 2 diabetes in Texas in 2007 attributable to not meeting physical activity Guidelines was estimated to be $1.15 billion, and that attributable to physical inactivity (no leisure time physical activity) was estimated to be $325 million. Depending on various assumptions, these estimates ranged from $800 million to $3.47 billion for not meeting Guidelines, and $186 million to $1.28 billion for physical inactivity in Texas in 2007. These results illustrate how much money could be saved annually just in terms of type 2 diabetes cost in the U.S. and Texas, if the entire adult population was active enough to meet physical activity Guidelines. Physical activity promotion, particularly at the environmental and policy level should be a priority in the population. ^

Disease risk factors and humoral antibody response to periodontal-associated pathogens: A model to evaluate periodontal disease in older adults

Periodontal diseases (PD) are infectious, inflammatory, and tissue destructive events which affect the periodontal ligament that surround and support the teeth. Periodontal diseases are the major cause of tooth loss after age 35, with gingivitis and periodontitis affecting 75% of the adult population. A select group of bacterial organisms are associated with periodontal pathogenesis. There is a direct association between oral hygiene and prevention of PD. The importance of genetic differences and host immune response capabilities in determining host, susceptibility or resistance to PD has not been established. This study examined the risk factors and serum (humoral) immune response to periodontal diseased-associated pathogens in a 55 to 80+ year old South Texas study sample with PD. This study sample was described by: age, sex, ethnicity, the socioeconomic factors marital status, income and occupation, IgG, IgA, IgM immunoglobulin status, and the autoimmune response markers rheumatoid factor (RF) and antinuclear antibody (ANA). These variables were used to determine the risk factors associated with development of PD. Serum IgG, IgA, IgM antibodies to bacterial antigens provided evidence for disease exposure.^ A causal model for PD was constructed from associations for risk factors (ethnicity, marital status, income, and occupation) with dental exam and periodontitis. The multiple correlation between PD and ethnicity, income and dental exam was significant. Hispanics of low income were least likely to have had a dental exam in the last year and most likely to have PD. The etiologic agents for PD, as evidenced by elevated humoral antibody responses, were the Gram negative microorganisms Bacteroides gingivalis, serotypes FDC381 and SUNYaBA7A1-28, and Wolinella recta. Recommendation for a PD prevention and control program are provided. ^

Pediatric motivational interviewing to address obesity and overweight

Not only are obesity and overweight associated with a myriad of medical and psychological concerns in childhood, but these health problems can persist even into adulthood. With the obvious need for better approaches in tackling childhood obesity and overweight and the strong evidence of motivational interviewing's effectiveness in the adult population, it is likely that an updated review will provide a more complete picture of the application of motivational interviewing in the pediatric population. The objective of this review is whether or not motivational interviewing will be instrumental in promoting factors that help in reducing the number of children who are or become overweight or obese. A literature search was completed that identified ten studies that incorporated MI as an intervention. Studies focused on either behavior health changes like increased physical activity, improved nutrition, or reducing parameters of weight like BMI or body composition. Three out of the 10 articles were still in progress and no results were provided. Five studies were able to achieve statistical significance in health benefits to control childhood overweight and obesity. Results revealed the overall feasibility of applying MI in the pediatric overweight and obese population, but the scarce number of studies limits conclusions about its efficacy. Therefore, additional scientific evidence is necessary to fully understand MI's role in affecting behavior changes in this population.^

Access to oral care --- A systematic review of a continuing public health issue among older adults

Oral health is essential for the general well being of the individual and collectively for the health of the population. Oral health can be maintained by routine dental care and visits to dental professionals, but accessing professional dental care may be a continuing difficulty in vulnerable older adult population. Many older adults are not frequent users of dental care, though oral health is crucial to their well-being and overall health. Access to care is the timely use of personal health services to achieve the best possible health outcomes. ^ Objectives: The aims of this review are to (i) to analyze and elucidate the relationship between socio-economic disparities in gender, ethnicity, poverty status, education and the continuing public issue of access to oral care, (ii) to identify the underlying causes through which these factors can affect access to oral care. This review will provide a knowledgeable basis for development of interventions to provide adequate access to oral care in older adults and implementing policies to ensure access to oral care; through highlighting the various socio economic factors that affect access to oral care among older adults. ^ Methods: This paper used a purposeful review of literature on socioeconomic disparities in access to oral care among older adults. The references considered in this review included all the relevant articles, surveys and reports published in English language, since the year 1985 to 2010, in the United States. The articles selected were scrutinized for relevancy to the topic of access to oral care and which included discussions of the effects of gender, ethnicity, poverty status, educational status in accessing oral care. ^ Results: Evidence confirmed the continuing disparity in access to oral care among older adults. The possible links identified were gender inequality, ethnic differences, income levels and educational differences affecting access to oral care. The underlying causes linking these factors with access to oral care were established. ^ Conclusion: The analysis of the literature review findings supported the prevalence of disparities in gender, ethnicity, income and education with its possible links affecting access to oral care. The underlying causes helped to understand the reasons behind this growing issue of inaccessible oral care. Further research is needed to develop policies and target dental public health efforts towards specific problem areas ensuring equitable access to oral services and consequently, improve the health of older adults.^

Evaluation of a wellness program at a large private sector petrochemical company in Texas

The study purpose was to analyze the effects Integrated Health Solutions (IHS), an employee wellness program that has been implemented for one year on the corporate campus of a major private sector petrochemical company in Houston, TX, has on employee health. ^ Chronic diseases are the leading causes of morbidity and mortality in the United States and are the most preventable of all health problems. The costs of chronic diseases in the working-age adult population include not only health problems and a decrease in quality of life, but also an increase the cost of health care and costs to businesses and employers, both directly and indirectly. These emerging costs to employers as well as the fact that adults now spend the majority of waking hours at the office have increased the interest in worksite health promotion programs that address many of the behavioral factors that lead to chronic conditions. Therefore, implementing and evaluating programs that are aimed at promoting health and decreasing the prevalence of chronic diseases at worksites is very important. ^ Data came from existing data that were collected by IHS staff during employee biometric screenings at the company in 2010 and 2011. Data from employees who participated in screenings in both 2010 and 2011 were grouped into a cohort by IHS staff. ^ One-tailed t-tests were conducted to determine if there were significant improvements in the biometric measures of body fat percentage, BMI, waist circumference, systolic and diastolic blood pressures, total, HDL, and LDL cholesterol levels, triglycerides, blood glucose levels, and cardiac risk ratios. Sensitivity analysis was conducted to determine if there were differences in program outcomes when stratified by age, gender, job type, and time between screenings. ^ Mean differences for the variables from 2010 to 2011 were small and not always in the desired direction for health improvement indicators. Through conducting t-tests, it was found that there were significant improvements in HDL, cardiac risk ratio, and glucose levels. There were significant increases in cholesterol, LDL, and diastolic blood pressures. For the IHS program, it appears that gender, job type, and time between screenings were possible modifiers of program effectiveness. When program outcome measures were stratified by these factors, results suggest that corporate employees had better outcomes than field employees, males had better outcomes overall than females, and more positive program effects were seen for employees with less time between their two screenings. ^ Recommendations for the program based on the results include ensuring validity of instruments and initial and periodic training of measurement procedures and equipment handling, using normative data or benchmarks to decrease chances for biased estimates of program effectiveness, measuring behaviors as well as biometric and physiologic statuses and changes, and collecting level of engagement data.^

The relationship between obesity, autoimmune disease, and C-reactive protein: A secondary data analysis of the National Health and Nutrition Examination Survey (NHANES) 2009--2010

Autoimmune diseases are a group of inflammatory conditions in which the body's immune system attacks its own cells. There are over 80 diseases classified as autoimmune disorders, affecting up to 23.5 million Americans. Obesity affects 32.3% of the US adult population, and could also be considered an inflammatory condition, as indicated by the presence of chronic low-grade inflammation. C-reactive protein (CRP) is a marker of inflammation, and is associated with both adiposity and autoimmune inflammation. This study sought to determine the cross-sectional association between obesity and autoimmune diseases in a large, nationally representative population derived from NHANES 2009–10 data, and the role CRP might play in this relationship. Overall, the results determined that individuals with autoimmune disease were 2.11 times more likely to report being overweight than individuals without autoimmune disease and that CRP had a mediating affect on the obesity-autoimmune relationship. ^

Multiple independent genetic factors at NOS1AP modulate the QT interval in a multi-ethnic population.

Extremes of electrocardiographic QT interval are associated with increased risk for sudden cardiac death (SCD); thus, identification and characterization of genetic variants that modulate QT interval may elucidate the underlying etiology of SCD. Previous studies have revealed an association between a common genetic variant in NOS1AP and QT interval in populations of European ancestry, but this finding has not been extended to other ethnic populations. We sought to characterize the effects of NOS1AP genetic variants on QT interval in the multi-ethnic population-based Dallas Heart Study (DHS, n = 3,072). The SNP most strongly associated with QT interval in previous samples of European ancestry, rs16847548, was the most strongly associated in White (P = 0.005) and Black (P = 3.6 x 10(-5)) participants, with the same direction of effect in Hispanics (P = 0.17), and further showed a significant SNP x sex-interaction (P = 0.03). A second SNP, rs16856785, uncorrelated with rs16847548, was also associated with QT interval in Blacks (P = 0.01), with qualitatively similar results in Whites and Hispanics. In a previously genotyped cohort of 14,107 White individuals drawn from the combined Atherosclerotic Risk in Communities (ARIC) and Cardiovascular Health Study (CHS) cohorts, we validated both the second locus at rs16856785 (P = 7.63 x 10(-8)), as well as the sex-interaction with rs16847548 (P = 8.68 x 10(-6)). These data extend the association of genetic variants in NOS1AP with QT interval to a Black population, with similar trends, though not statistically significant at P<0.05, in Hispanics. In addition, we identify a strong sex-interaction and the presence of a second independent site within NOS1AP associated with the QT interval. These results highlight the consistent and complex role of NOS1AP genetic variants in modulating QT interval.