Asian-American citizens are the fastest growing racial/ethnic group in the United States. Nevertheless, data on Asian American health are scarce, and many health disparities for this population remain unknown. Much of our knowledge of Asian American health has been determined by studies in which investigators have either grouped Asian-American subjects together or examined one subgroup alone (e.g., Asian Indian, Chinese, Filipino, Japanese, Korean, Vietnamese). National health surveys that collect information on Asian-American race/ethnicity frequently omit this population in research reports. When national health data are reported for Asian-American subjects, it is often reported for the aggregated group. This aggregation may mask differences between Asian-American subgroups. When health data are reported by Asian American subgroup, it is generally reported for one subgroup alone. In the Ni-Hon-San study, investigators examined cardiovascular disease in Japanese men living in Japan (Nippon; Ni), Honolulu, Hawaii (Hon), and San Francisco, CA (San). The findings from this study are often incorrectly extrapolated to other Asian-American subgroups. Recommendations to correct the errors associated with omission, aggregation, and extrapolation include: oversampling of Asian Americans, collection and reporting of race/ ethnicity data by Asian-American subgroup, and acknowledgement of significant heterogeneity among Asian American subgroups when interpreting data.
Asian American; Data Collection; Research Design; Research Methodology
This article describes the conceptual model developed for the Hispanic Community Health Study/Study of Latino Youth, a multisite epidemiologic study of obesity and cardiometabolic risk among U.S. Hispanic/Latino children.
Public health, psychology, and sociology research were examined for relevant theories and paradigms. This research, in turn, led us to consider several study design features to best represent both risk and protective factors from multiple levels of influence, as well as the identification of culturally relevant scales to capture identified constructs.
The Socio-Ecological Framework, Social Cognitive Theory, family systems theory, and acculturation research informed the specification of our conceptual model. Data are being collected from both children and parents in the household to examine the bidirectional influence of children and their parents, including the potential contribution of intergenerational differences in acculturation as a risk factor. Children and parents are reporting on individual, interpersonal, and perceived organizational and community influences on children's risk for obesity consistent with Socio-Ecological Framework.
Much research has been conducted on obesity, yet conceptual models examining risk and protective factors lack specificity in several areas. Study of Latino Youth is designed to fill a gap in this research and inform future efforts.
Hispanic/Latino; Children; Obesity; Acculturation; Socio-Ecological Framework; Theory
To assess the associations between cruciferous vegetable (CV) intake, GST gene polymorphisms and colorectal cancer (CRC) in a population of Chinese men.
Using incidence density sampling, CRC cases (N = 340) diagnosed prior to December 31, 2010 within the Shanghai Men’s Health Study were matched to non-cases (N = 673). CV intake was assessed from a food frequency questionnaire and by isothiocyanate (ITC) levels from spot urine samples. GSTM1 and GSTT1 were categorized as null (0 copies) versus non-null (1 or 2 copies). Conditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs) for the association between CV intake and GST gene variants with CRC and statistical interactions were evaluated.
CRC risk was not associated with CV intake, whether measured by self-report or by urinary ITC, nor with GST gene variants. No statistical interactions were detected between CV intake and GST gene variants on the odds of CRC. Stratifying by timing of urine sample collection and excluding CRC cases diagnosed in the first two years did not materially alter the results.
This study provides no evidence supporting the involvement of CV intake in the development of CRC in Chinese men.
brassicaceae; China; colorectal neoplasms; glutathione S-transferase M1; glutathione S-transferase T1; men
This paper describes the design and methodology of the SOL Youth study, a multicenter study of Hispanic/Latino children living in the US.
Participants are children aged 8–16 years whose parents/legal guardians participated in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), a large community-based cohort study of Hispanic/Latino adults living in the US.
Between 2012 and 2014, 1600 children recruited from 4 field centers (Bronx, Chicago, Miami and San Diego) will undergo a 3.5 hour examination to collect biospecimens, obtain anthropometric measures, blood pressure, fitness level, dietary intake, and physical activity. Psychosocial and environmental characteristics are assessed by questionnaire. Primary study aims are to examine associations of youth’s lifestyle behaviors and cardiometabolic risk factors with (1) youth’s acculturation and parent-child differences in acculturation; (2) parenting strategies, family behaviors, and parental health behaviors; and (3) youth’s psychosocial functioning.
SOL Youth will determine the prevalence and distribution of obesity-promoting lifestyle behaviors, cardiometabolic risk profiles and novel biomarkers associated with obesity and insulin resistance. This paper describes the study methodology and considers advantages and limitations of embedding a cohort of children within a well characterized cohort of adults.
Little research has been done in China to study injury in individuals with disability. We investigated impact of type and severity of disability on injury among children with disability in Hubei Province of China.
A sample of 1201 children with disability were matched with 1201 healthy children on gender, age, and neighborhood. Disability type and severity were determined using the Chinese national standards. Caregivers were interviewed face-to-face about nonfatal unintentional injuries suffered by the child in the past 12 months prior to the interview. Univariate Chi-square test and logistic regression models were used to investigate association between disability type/severity and nonfatal unintentional injuries.
Injury rate among children with disability was significantly higher than that among children without disability (10.2% vs. 4.4%; P <.001). Children with multiple disabilities had the highest risk of injury after controlling for confounding variables (OR=4.54; 95% CI=2.82, 7.30; P<.001). The magnitude of the association between disability and injury varied by type and severity of disability.
The magnitude of the association between the presence or absence of disability in children and their risk of injury was large and significant, regardless of the type or severity of the children's disabilities.
Unintentional injury; Children; Disability; China
Although risk factors for squamous cell carcinoma of the esophagus (SCC) and adenocarcinomas of the esophagus (EA), gastric cardia (GC) and other (non-cardia) gastric sites (OG) have been identified, little is known about interactions among risk factors. We sought to examine interactions of diet, other lifestyle, and medical factors with risks of subtypes of esophageal and gastric cancer.
We used classification tree analysis to analyze data from a population-based case-control study (1,095 cases, 687 controls) conducted in Connecticut, New Jersey, and western Washington State.
Frequency of reported gastroesophageal reflux (GERD) symptoms was the most important risk stratification factor for EA, GC, and OG, with dietary factors (EA, OG), smoking (EA, GC), wine intake (GC, OG), age (OG), and income (OG) appearing to modify risk of these cancer sites. For SCC, smoking was the most important risk stratification factor, with GERD, income, race, non-citrus fruit, and energy intakes further modifying risk.
Various combinations of risk factors appear to interact to affect risk of each cancer subtype. Replication of these data-mining analyses are required before suggesting causal pathways; however, the classification tree results are useful in partitioning risk and mapping multi-level interactions among risk variables.
esophageal adenocarcinoma; gastric cardia adenocarcinoma; diet; gastroesophageal reflux; classification tree; CART
Few population-based studies have estimated the number of persons diagnosed with chronic hepatitis B (CHB) infection in the United States. Our objective was to estimate the prevalence of diagnosed CHB infection among persons enrolled in the U.S. Medicaid programs of California, Florida, New York, Ohio, and Pennsylvania between 2000 and 2007. As part of our analyses, we confirmed the accuracy of CHB diagnoses within the Medicaid database.
CHB infection was defined by the presence of two outpatient CHB diagnoses recorded more than 6 months apart. Two clinicians reviewed the medical records of a random sample of patients who met this definition to confirm the diagnosis, which enabled calculation of the positive predictive value (PPV). The period prevalence of diagnosed CHB infection among Medicaid enrollees with at least 6 months of membership from 2000–2007 was then estimated, adjusting for both the PPV and estimated sensitivity of our definition of CHB infection.
The definition of CHB infection accurately identified clinician-confirmed cases (PPV, 96.3%; 95% confidence interval [CI], 87.3–99.5). Using this definition, 31,046 cases of CHB were diagnosed among 31,358,010 eligible Medicaid members from the five states (prevalence, 9.9 [95% CI, 9.8–10.0] per 10,000). Adjusting for the PPV and estimated sensitivity of our CHB definition, the prevalence of diagnosed CHB infection was 15.6 (95% CI, 15.4–15.7) per 10,000.
Two outpatient CHB diagnoses recorded more than 6 months apart validly identified clinician-confirmed CHB. The prevalence of diagnosed CHB infection among U.S. Medicaid enrollees was 15.6 per 10,000.
Hepatitis B; viral hepatitis; prevalence
Assessment of cortisol concentrations in hair is one of the latest innovations for measuring long-term cortisol exposure. We performed a systematic review of correlates of cortisol in human hair to inform the design, analysis and interpretation of future epidemiologic studies. Relevant publications were identified through electronic searches on PubMed, WorldCat, and Web of Science using keywords, “cortisol” “hair” “confounders” “chronic” “stress” and “correlates.” Thirty-nine studies were included in this review. Notwithstanding scarce data and some inconsistencies, investigators have found hair cortisol concentrations to be associated with stress-related psychiatric symptoms and disorders (e.g., PTSD), medical conditions indicating chronic activation of the hypothalamic-pituitary-adrenal axis (e.g., Cushing´s syndrome) and other life situations associated with elevated risk of chronic stress (e.g., shiftwork). Results from some studies suggest that physical activity, adiposity, and substance abuse may be correlates of hair cortisol concentrations. In contrast to measures of short-term cortisol release (saliva, blood, and urine), cigarette smoking and use of oral contraceptives appear to not be associated with hair cortisol concentrations. Studies of pregnant women indicate increased hair cortisol concentrations across successive trimesters. The study of hair cortisol presents a unique opportunity to assess chronic alterations in cortisol concentrations in epidemiologic studies.
hair; cortisol; chronic stress; correlates; assessment; analysis; determinants; psychiatric disorders
Determinants of oxidative capacity, such as fitness and level of adiposity, are strongly associated with type 2 diabetes. Whether decreased oxidative capacity itself is a cause or consequence of insulin resistance and diabetes is unknown.
We examined the association of plasma lactate, a marker of oxidative capacity, with incident diabetes in 8,045 participants from the Atherosclerosis Risk in Communities (ARIC) Study with no history of subclinical or diagnosed diabetes at baseline (1996–1998). Incident diabetes was self-reported during annual telephone calls.
During a median follow-up of 12 years, there were 1,513 new cases of diabetes. In Cox proportional hazards models, baseline plasma lactate (per 10 mg/dL) was significantly associated with diabetes (HR 1.20, 95% CI: 1.01, 1.43), even after adjustment for diabetes risk factors, fasting glucose, and insulin. The upper quartile of baseline lactate (≥ 8.1 mg/dL) was also significantly associated with diabetes risk (HR 1.20, 95% CI: 1.02, 1.41) compared with the lowest quartile (≤ 5.1 mg/dL). Significant associations persisted among persons without insulin resistance (HOMA-IR < 2.6 units) (P-trend <0.01).
These findings suggest that low oxidative capacity may precede diabetes. Future studies should evaluate the physiologic origins of elevated lactate to better understand its possible role in the pathogenesis of diabetes.
Lactate; Diabetes risk; Cohort; ARIC
To examine the effect of lifetime social hardships on fertility.
Using the British National Child Development Study, a longitudinal cohort study, the impact of exposure to childhood hardships on becoming pregnant, reported infertility, and time to pregnancy was investigated. 6477 women reported on whether they had become pregnant by age 41, and 5198 women had data on at least one pregnancy. Factor analysis was used to identify six types of childhood hardships (as reported by parent, child, social worker, or teacher); retrospective report of child abuse was also examined. Logistic regression and discrete failure-time analysis was used to adjust for potential confounders.
Never-married women were more likely to have become pregnant at some point if they had experienced more childhood hardships. Retrospectively reported child abuse was associated with an increased likelihood of having been told one was unable to have children. Among ever-married women, childhood hardships were associated with reduced fecundability, but the association was weakened by adjustment for adult social class.
The relationship between childhood adversity and adult fertility is complex. Future research should investigate pathways between characteristics of adversities and fertility.
adversity; fertility; pregnancy; socioeconomic status
Much debate exists regarding the role of culture versus socioeconomic position in shaping the health of Latino populations. We propose that both may matter for health and explicitly test their independent and joint effects on smoking and physical activity.
We used the 2010 National Health Interview Survey, a population-based survey of the U.S. population, to estimate the prevalence of smoking and physical activity by language use (cultural proxy) and education among Latino adults (n = 4929). We fit log binomial regression models to estimate prevalence ratios and test for interaction.
English-language use and educational attainment were each independently associated with smoking and physical activity. Joint effect models showed that individuals with both greater use of the English language and low levels of education were nearly three times more likely to smoke (prevalence ratio, 2.59; 95% confidence interval, 1.83–3.65) than those with low English language use and high education (referent group); high acculturation and high education were jointly associated with increased activity (prevalence ratio 2.24, 95% confidence interval, 1.79–2.81).
Cultural proxies such as language use and educational attainment are both important determinants of health among Latinos. Their joint effect suggests the need to simultaneously consider Latinos' socioeconomic position and their increased risk of adopting health-damaging behaviors while addressing culturally-specific factors that may mitigate risk.
Hispanic Americans; Acculturation; Education; Smoking; Physical activity
Lead-time is inherent in early detection and creates bias in observational studies of screening efficacy, but its potential to bias effect estimates in risk-factor studies is not always recognized. We describe a form of this bias that conventional analyses cannot address and develop a model to quantify it.
Surveillance Epidemiology and End Results (SEER) data form the basis for estimates of age-specific preclinical incidence and log-normal distributions describe the preclinical duration distribution. Simulations assume a joint null hypothesis of no effect of either the risk factor or screening on the preclinical incidence of cancer, and then quantify the bias as the risk-factor odds ratio (OR) from this null study. This bias can be used as a factor to adjust observed OR in the actual study.
Results showed that for this particular study design, as average preclinical duration increased, the bias in the total-physical-activity OR monotonically increased from 1% to 22% above the null, but the smoking OR monotonically decreased from 1% above the null to 5% below the null.
The finding of nontrivial bias in fixed risk-factor effect estimates demonstrates the importance of quantitatively evaluating it in susceptible studies.
methodological study; case-control study; early diagnosis of cancer; cancer screening; mathematical model; bias
Social and economic contextual factors may promote concurrent sexual partnerships, which can accelerate population HIV/STI transmission and are more common among African Americans than U.S. Whites. We investigated the relationship between contextual factors and concurrency.
We analyzed past-12-month concurrency prevalence in the 2002 National Survey of Family Growth and its contextual database in relation to county sex ratio (among respondent’s racial/ethnic group), percentage in poverty (among respondent’s racial/ethnic group), and violent crime rate. Analyses examined counties with balanced (0.95–1.05 males/female) or low (<0.9) sex ratios.
Concurrency prevalence was greater (OR; 95% CI) in counties with low sex ratios (1.67; 1.17, 2.39), more poverty (OR 1.18; 0.98, 1.42 per 10 percentage-point increase), and higher crime rates (OR 1.04; 1.00,1.09 per 1,000 population/year). Notably, 99.5% of Whites and 93.7% of Hispanics, but only 7.85% of Blacks, lived in balanced sex ratio counties; about 5% of Whites, half of Hispanics and three-fourths of Blacks resided in counties with > 20% same-race poverty.
The dramatic Black-White differences in contextual factors in the US and their association with sexual concurrency could contribute to the nation’s profound racial disparities in HIV infection.
Concurrent partnerships; African Americans; HIV; epidemiology; multilevel analysis; sex ratio; Hispanics
Intimate partner violence is a worldwide public health concern predominantly affecting women of reproductive age. The purpose of this study was to evaluate the effect of exposure to intimate partner violence before, during or after pregnancy on postpartum depression in a nationally representative sample of Canadian women.
A cross-sectional analysis was performed using data from the Maternity Experience Survey conducted by Statistics Canada in 2006. A population-based sample of 8,542 women 15 years and older who delivered singleton live births was selected from all Canadian provinces and territories; of those, 6,421 completed a computer-assisted telephone interview. Recent experiences with and threats of physical or sexual violence by an intimate partner were examined in relation to postpartum depression assessed through the Edinburgh Postpartum Depression Scale.
The prevalence of postpartum depression was 7.5% (95% CI: 6.8, 8.2). Controlling for confounders, odds of postpartum depression were significantly higher among women who reported partner violence in the past two years as opposed to those who did not (adjusted OR=1.61; 95% CI: 1.06, 2.45).
Intimate partner violence is positively associated with postpartum depression among Canadian women. Implications for healthcare practice are discussed.
postpartum depression; intimate partner violence; pregnancy; survey
To evaluate the influence of alcohol consumption on the risk of colorectal cancer according to folic acid fortification period in the United States.
We evaluated the association between alcohol consumption and colorectal cancer by fortification period (before 1998 vs. after 1998) in two prospective cohort studies, Nurses’ Health Study (NHS) of women and Health Professionals Follow-up Study (HPFS) of men, in which 2,793 invasive colorectal cancer cases were documented.
Alcohol consumption was associated with an increased risk of colorectal cancer. Among non-users of multivitamins and/or folic acid supplements, the pooled multivariate relative risk (RR) for ≥30g/d drinkers versus non-drinkers was 1.36 (95% CI, 1.09–1.70; p for trend, 0.02). The effect of alcohol consumption was slightly stronger in the pre-folic acid fortification period (1980 NHS/1986 HPFS-1998) than in the post-fortification period (1998–2008); the pooled multivariate RRs for ≥30g/d drinkers versus non-drinkers were 1.31 (95% CI, 1.00–1.71; p for trend, 0.10) in the pre-fortification period and 1.07 (95% CI, 0.69–1.65; p for trend, 0.67) in the post-fortification period.
Folic acid fortification may attenuate the adverse effect of high alcohol consumption on the risk of colorectal cancer.