Glutathione metabolism in type 2 diabetes and its relationship with microvascular complications and glycemia.

Aims/hypotheses: We hypothesized that there is decreased synthesis of glutathione (GSH) in type 2 diabetes (T2DM) especially in the presence of microvascular complications, and this is dependent on the degree of hyperglycemia.

Methods: In this case-control study, we recruited 16 patients with T2DM (7 without and 9 with microvascular complications), and 8 age- and sex-matched non-diabetic controls. We measured GSH synthesis rate using an infusion of [2H2]-glycine as isotopic tracer and collection of blood samples for liquid chromatography mass spectrometric analysis.

Effects of cholesterol, C-reactive protein, and interleukin-6 on prostate cancer risk in a population of African ancestry.

Purpose: To investigate the association between serum cholesterol and prostate cancer and whether any effect may be mediated through inflammatory markers.

Methods: Data from a case-control study of 40-80 years old Jamaican male patients (229 cases; 252 controls) were used. Cases had incident histologically-confirmed prostate cancer and controls were men with normal digital rectal examination and prostate-specific antigen (PSA) < 4 μg/L or free: total PSA > 0.

Increased Dietary Inflammatory Index (DII) Is Associated With Increased Risk of Prostate Cancer in Jamaican Men.

Prostate cancer is the most common nonskin malignancy, and it accounts for the most cancer deaths among Jamaican males. Diet has been implicated in the etiology of prostate cancer, including through its effects on inflammation. We examined the association between a newly developed dietary inflammatory index (DII) and prostate cancer in a case-control study of 40-80 yr old Jamaican males.

Both serum 25-hydroxyvitamin D and calcium levels may increase the risk of incident prostate cancer in Caribbean men of African ancestry.

Circulating 25-hydroxyvitamin D [25(OH)D] concentrations have been associated with both higher and lower risk of prostate cancer (PCa), whereas elevated levels of circulating calcium has been related to higher risks. However, there are few studies that account for effects of both calcium and 25(OH)D concentrations on incident PCa in a black population. We examined these relationships in a case-control study of men 40-80 years old with newly diagnosed, histologically confirmed PCa in Jamaica, a tropical country.

High-Sensitivity C-Reactive Protein is Related to Central Obesity and the Number of Metabolic Syndrome Components in Jamaican Young Adults.

Background: High-sensitivity C-reactive protein (hsCRP) has been shown to predict cardiovascular disease (CVD) endpoints and is associated with CVD risk factors and the metabolic syndrome. This study evaluated the association between hsCRP and CVD risk factors among Afro-Caribbean young adults in Jamaica.

Methods: We conducted a cross-sectional analysis of data from the Jamaica 1986 Birth Cohort Study.

Discovery and refinement of loci associated with lipid levels.

Levels of low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides and total cholesterol are heritable, modifiable risk factors for coronary artery disease. To identify new loci and refine known loci influencing these lipids, we examined 188,577 individuals using genome-wide and custom genotyping arrays. We identify and annotate 157 loci associated with lipid levels at P < 5 × 10(-8), including 62 loci not previously associated with lipid levels in humans.

Common variants associated with plasma triglycerides and risk for coronary artery disease.

Triglycerides are transported in plasma by specific triglyceride-rich lipoproteins; in epidemiological studies, increased triglyceride levels correlate with higher risk for coronary artery disease (CAD). However, it is unclear whether this association reflects causal processes. We used 185 common variants recently mapped for plasma lipids (P < 5 × 10(-8) for each) to examine the role of triglycerides in risk for CAD.

Dietary patterns as predictors of prostate cancer in Jamaican men.

Studies of diet and prostate cancer have focused primarily on food and nutrients; however, dietary patterns examine the overall diet, particularly foods eaten in combination, and risk of disease. We evaluated the association of dietary patterns and prostate cancer and low- and high-grade subgroups in Jamaican men. In a case-control study, we enrolled 243 incident cases and 273 urology controls in Jamaican clinics, March 2005-July 2007.

Complex interaction between serum folate levels and genetic polymorphisms in folate pathway genes: biomarkers of prostate cancer aggressiveness.

Little is known about the role of folate and polymorphisms associated with folate metabolism on prostate cancer risk in populations of African origin. We examined the relationship between serum folate and prostate cancer and whether any association was modified by genetic polymorphisms for folate metabolism. The study was case-control in design and consisted of 218 men 40-80 years old with newly diagnosed, histologically confirmed prostate cancer and 236 cancer-free men attending the same urology clinics in Jamaica, March 2005-July 2007.

Associations of whole-blood fatty acids and dietary intakes with prostate cancer in Jamaica.

Objective: To investigate the association of whole-blood fatty acids and reported intakes of fats with risk of prostate cancer (PCa).

Design: Case-control study of 209 men 40-80 years old with newly diagnosed, histologically confirmed prostate cancer and 226 cancer-free men attending the same urology clinics. Whole-blood fatty acid composition (mol%) was measured by gas chromatography and diet assessed by food frequency questionnaire.

Use of a food frequency questionnaire to assess diets of Jamaican adults: validation and correlation with biomarkers.

Background: Assessment of habitual diet is important in investigations of diet-disease relationships. Many epidemiological studies use the food frequency questionnaire (FFQ) to evaluate dietary intakes but few studies validate the instrument against biological markers. The aim of this study was to assess the validity and reproducibility of a previously validated 70-item food frequency questionnaire (FFQ) that was expanded to 120-items to assess diet-cancer relations.

Genome-wide association study of coronary heart disease and its risk factors in 8,090 African Americans: the NHLBI CARe Project.

Coronary heart disease (CHD) is the leading cause of mortality in African Americans. To identify common genetic polymorphisms associated with CHD and its risk factors (LDL- and HDL-cholesterol (LDL-C and HDL-C), hypertension, smoking, and type-2 diabetes) in individuals of African ancestry, we performed a genome-wide association study (GWAS) in 8,090 African Americans from five population-based cohorts. We replicated 17 loci previously associated with CHD or its risk factors in Caucasians.

Urinary phytoestrogens and risk of prostate cancer in Jamaican men.

We evaluated the relationship of spot urinary concentrations of phytoestrogens with total prostate cancer and tumor grade in a hospital-based case-control study in Jamaica. Urine samples were analyzed for genistein, daidzein, equol (isoflavones), and enterolactone (lignan) among newly diagnosed cases (n = 175) and controls (n = 194). Urinary concentrations of enterolactone (lignan) were higher among cases.

Sex-differences in adiponectin levels and body fat distribution: longitudinal observations in Afro-Jamaicans.

We longitudinally explored the relationship of body size and adiponectin levels in 393 community-dwelling Afro-Jamaicans. Adiponectin levels were greater in women, increased with age and declined with abdominal adiposity. Multivariate regression analyses suggest that subcutaneous fat in women may contribute significantly to the variance in their adiponectin levels.

Body size and risk of prostate cancer in Jamaican men.

We investigated the associations between body size and risk of prostate cancer in a hospital-based case-control study in Jamaica. Height, weight, waist, and hip circumference were measured at enrollment, and data collected on medical and lifestyle factors for newly diagnosed cases (n = 243) and controls (n = 275). Compared with men in the normal range of waist-hip ratio (WHR), men with WHR > or =0.

Are food patterns associated with prostate cancer in Jamaican men: a preliminary report.

Background: Morbidity and mortality data highlight prostate cancer as the most commonly diagnosed neoplasm in Jamaican males. This report examines the association between dietary patterns and risk of prostate cancer in Jamaican men.

Materials And Methods: Case-control study of 204 histologically confirmed newly diagnosed prostate cancer cases and 204 individually matched urology clinic controls in Jamaica, 2004 - 2007.

The association of hypothalamic-pituitary-adrenal axis activity and blood pressure in an Afro-Caribbean population.

Hyperactivity of the hypothalamic-pituitary-adrenal axis (HPAA) resulting from fetal programming may play a role in the development of high blood pressure (BP) in black people. We assessed the diurnal salivary cortisol profile in children with and without increased BP and evaluated their mother's HPAA. In a cross-sectional study, 20 Afro-Caribbean children (mean age 9.

Impact of adiponectin and ghrelin on incident glucose intolerance and on weight change.

Objectives: Adiponectin and ghrelin are associated with adiposity and type 2 diabetes in several studies. We sought to prospectively determine the interaction of adiponectin and ghrelin in the development of adiposity and hyperglycaemia.

Design: Prospective observational study.

African-Caribbean cancer consortium for the study of viral, genetic and environmental cancer risk factors.

This is a short summary of a meeting of the "African-Caribbean Cancer Consortium", jointly organized by the University of Pittsburgh, Department of Epidemiology and the University of Pittsburgh Cancer Institute, held in Montego Bay, Jamaica as a satellite meeting at the Caribbean Health Research Council, 52nd Annual Council and Scientific meeting on May 4, 2007.

Factors affecting study efficiency and item non-response in health surveys in developing countries: the Jamaica national healthy lifestyle survey.

Background: Health surveys provide important information on the burden and secular trends of risk factors and disease. Several factors including survey and item non-response can affect data quality. There are few reports on efficiency, validity and the impact of item non-response, from developing countries.

Association of growth in utero with cognitive function at age 6-8 years.

Background: Size at birth is associated with later cognitive development. The timing of growth faltering in utero may affect developmental consequences.

Aim: To determine whether growth in utero is related to cognitive outcomes in childhood.

Isoprostanes, a marker of lipid peroxidation, may not be involved in the development of glucose intolerance.

We investigated whether isoprostanes, as a marker of lipid peroxidation, may be involved in the development of impaired glucose tolerance (IGT) or diabetes. Using a nested case-control study, we tracked the changes in isoprostane levels, insulin sensitivity (IS) and beta-cell function (BCF) in Afro-Jamaicans who progressed to IGT and diabetes over 3.9 years.

Maternal body composition, offspring blood pressure and the hypothalamic-pituitary-adrenal axis.

We tested the hypothesis that women who are thin or have poor pregnancy weight gain have offspring with higher blood pressure and examined whether this link is mediated by increased secretion of cortisol. We studied a cohort of 388 children born in Kingston, Jamaica. From hospital records we obtained information about their mother's body mass index (BMI) and weight gain during pregnancy.

Impaired glucose regulation in adults in Jamaica: who should have the oral glucose tolerance test?

Objective: To compare the 1999 World Health Organization (WHO) fasting plasma glucose (FPG) criteria and the WHO 2-hour post-challenge glucose (2hPG) criteria during an oral glucose tolerance test (OGTT) in identifying adults in Jamaica with hyperglycemia. As the OGTT is not commonly used in clinical practice, factors associated with the failure of the FPG criteria to detect persons with impaired 2hPG were investigated.

Methods: A random sample of 2 096 adults, 25-74 years old, living in the town of Spanish Town, Jamaica, was evaluated for diabetes.

The relationship among circulating insulin-like growth factor (IGF)-I, IGF-binding proteins-1 and -2, and birth anthropometry: a prospective study.

Fetal IGF-I is a determinant of birth weight, but whether maternal IGF-I plays a significant role is controversial. We sought to examine the relationships among maternal IGF-I, IGF-binding protein (IGFBP)-1, and IGFBP-2, with maternal and newborn anthropometry, in a cohort of 325 nondiabetic pregnant women of African origin. Blood was collected for IGF-I, IGFBP-1, and IGFBP-2 at 9, 25, and 35 wk gestation and in cord blood at delivery.