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 > 0.15 obtained from the same clinic. Total and HDL cholesterol, interleukin-6 (IL-6), and C-reactive protein (CRP) were measured from a non-fasting sample. Multivariable logistic regression models were used to evaluate the associations between these factors and prostate cancer, adjusting for age, body mass index, waist circumference, family history of prostate cancer, diabetes, hypertension, use of cholesterol-lowering drugs, and smoking. RESULTS: Total cholesterol [Mean (cases, 4.71 ± 1.07; controls, 4.64 ± 1.07 mmol/L)], CRP [median (cases, 2.11; controls, 2.09 µg/ml)], and IL-6: [median (cases, 3.34; controls, 3.24 pg/ml)] did not differ by PCA status. Higher total cholesterol was associated with an increased risk of low-grade disease after adjusting for potential confounders [multivariable-adjusted OR (95% CI): tertile 2: 3.32(1.66, 6.45), tertile 3: 2.14(1.07, 4.32)]. Total cholesterol was unrelated to overall prostate cancer or high-grade disease. There was no significant association between HDL cholesterol or any of the inflammatory markers with prostate cancer. CONCLUSIONS: Increasing total cholesterol but not inflammatory markers were associated with low-grade prostate cancer in Caribbean men.

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. A total of 229 incident cases and 250 controls attended the same urology out-patient clinics at 2 major hospitals and private practitioners in the Kingston, Jamaica metropolitan area between March 2005 and July 2007. The DII was computed based on dietary intake assessed using a previously validated food frequency questionnaire (FFQ) that was expanded to assess diet and cancer in this Jamaican population. Multivariable logistic regression was used to estimate odds ratios, with DII as continuous and expressed as quartiles. Logistic regression analysis adjusted for age, total energy intake, education, body mass index, smoking status, physical activity, and family history of prostate cancer. Men in the highest quartile of the DII were at higher risk of prostate cancer [odds ratio (OR) = 2.39; 95% confidence interval (CI) = 1.14-5.04; P(trend) = 0.08] compared to men in the lowest DII quartile. These data suggest a proinflammatory diet, as indicated by increasing DII score, may be a risk factor for prostate cancer in Jamaican men.

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. For five of these regions (CHD: CDKN2A/CDKN2B; HDL-C: FADS1-3, PLTP, LPL, and ABCA1), we could leverage the distinct linkage disequilibrium (LD) patterns in African Americans to identify DNA polymorphisms more strongly associated with the phenotypes than the previously reported index SNPs found in Caucasian populations. We also developed a new approach for association testing in admixed populations that uses allelic and local ancestry variation. Using this method, we discovered several loci that would have been missed using the basic allelic and global ancestry information only. Our conclusions suggest that no major loci uniquely explain the high prevalence of CHD in African Americans. Our project has developed resources and methods that address both admixture- and SNP-association to maximize power for genetic discovery in even larger African-American consortia.

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. Dietary patterns were identified using principal component analysis. Four food patterns were identified: a "vegetable and legume" pattern, a "fast food" pattern, a "meat" pattern, and a "refined carbohydrate" pattern. Men in the highest tertile for the refined carbohydrate pattern, characterized by high intakes of rice, pasta, sugar sweetened beverages, and sweet baked foods were at increased risk of total prostate cancer [odds ratio (OR) = 2.02; 95% confidence interval (CI) = 1.05-3.87 (Ptrend = 0.029)] and low-grade disease [OR = 2.91; 95% CI = 1.18-7.13 (Ptrend = 0.019)] compared with men in the lowest tertile. The vegetable and legumes pattern (healthy), meat pattern, or fast food pattern were not associated with prostate cancer risk. These data suggest a carbohydrate dietary pattern high in refined carbohydrates may be a risk factor for prostate cancer in Jamaican men.

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. RESULTS: High whole-blood oleic acid composition (tertile 3 vs. tertile 1: OR, 0.37; CI, 0.14-0.0.98) and moderate palmitic acid proportions (tertile 2: OR, 0.29; CI, 0.12-0.70) (tertile 3: OR, 0.53; CI, 0.19-1.54) were inversely related to risk of PCa, whereas men with high linolenic acid proportions were at increased likelihood of PCa (tertile 3 vs. tertile 1: OR, 2.06; 1.29-3.27). Blood myristic, stearic and palmitoleic acids were not associated with PCa. Higher intakes of dietary MUFA were inversely related to prostate cancer (tertile 3 vs. tertile 1: OR, 0.39; CI 0.16-0.92). The principal source of dietary MUFA was avocado intake. Dietary intakes of other fats were not associated with PCa. CONCLUSIONS: Whole-blood and dietary MUFA reduced the risk of prostate cancer. The association may be related to avocado intakes. High blood linolenic acid was directly related to prostate cancer. These associations warrant further investigation.

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. METHODS: Relative validity of the FFQ was assessed against twelve 24-hour recalls administered over 12 months in 70 subjects. The FFQ was repeated after one year (FFQ2) to assess reproducibility. The validity of the FFQ was evaluated by comparing nutrient and food group intakes from 24-hour recalls with the first and second FFQ. In addition, FFQ validity for cholesterol and folate were determined through correlation with biomarkers (serum cholesterol, serum folate and whole blood folate) in 159 control subjects participating in a case-control prostate cancer study. RESULTS: Compared to recalls the FFQ tended to overestimate energy and carbohydrate intakes but gave no differences in intake for protein and fat. Quartile agreement for energy-adjusted nutrient intakes between FFQ2 and recalls ranged from 31.8%-77.3% for the lowest quartile and 20.8%-81.0% in the highest quartile. Gross misclassification of nutrients was low with the exceptions of protein, vitamin E and retinol and weighted kappa values ranged from 0.33 to 0.64 for other nutrients. Validity correlations for energy-adjusted nutrients (excluding retinol) were moderate to high (0.38-0.86). Correlation coefficients between multiple recalls and FFQ1 ranged from 0.27 (fruits) to 0.55 (red meat); the second FFQ gave somewhat higher coefficients (0.30 to 0.61). Reproducibility correlations for the nutrients ranged from 0.50 to 0.84.Calibration of the FFQ with biochemical markers showed modest correlations with serum cholesterol (0.24), serum folate (0.25) and whole blood folate (0.33) adjusted for age, energy, body mass index and smoking. CONCLUSIONS: The expanded FFQ had good relative validity for estimating food group and nutrient intakes (except retinol and vitamin E) and was a reliable measure of habitual intake. Associations with biomarkers were comparable to other studies.

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. There were no significant differences in median concentrations of isoflavone excretion. Compared with non-producers of equol (reference tertile), men who produced equol were at decreased risk of total prostate cancer (tertile 2: OR, 0.42; CI, 0.23-0.75) (tertile 3: OR, 0.48; CI, 0.26-0.87) (p (trend), 0.020) and high-grade disease (tertile 2: OR, 0.31; CI, 0.15-0.61) (tertile 3: OR, 0.29; CI, 0.13-0.60) (p (trend), 0.001). Higher concentrations of enterolactone were positively related to total prostate cancer (OR, 1.85; CI, 1.01-3.44; p (trend), 0.027) as well as high-grade disease (OR, 2.46; CI, 1.11-5.46; p (trend), 0.023). There were no associations between urinary excretion of genistein and daidzein with risk of prostate cancer. Producers of equol (isoflavone) may be at reduced risk of total- and high-grade prostate cancer whereas enterolactone may increase the likelihood of disease.

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 =0.95 were at greater risk of total prostate cancer (OR,1.72; CI, 1.01-3.00) and high-grade cancer (OR, 2.02; CI, 1.03-3.96). With additional control for BMI, the association with WHR remained significant for total prostate cancer (OR, 1.90; CI, 1.01-3.53) and high-grade disease (OR, 2.94; CI, 1.34-6.38). There was no association between waist circumference and cancer without control for BMI but after controlling for BMI, waist circumference >90 cm (OR, 2.45; CI, 1.01-5.94) and >102 cm (OR, 5.57; CI, 1.43-18.63) showed a dose-response relationship with high-grade disease. Height and BMI were not associated with risk of prostate cancer. Abdominal obesity may be associated with risk of high-grade prostate cancer. Risk may be greater in those with higher abdominal obesity relative to overall size. The results further highlight the importance of investigating relationships by characteristics of the tumor.

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. PARTICIPANTS: 393 community-dwelling Afro-Jamaicans (mean age 47 +/- 13 years; BMI 27.3 +/- 6.3 kg/m(2); 63% women) without glucose intolerance at baseline. MEASUREMENTS: Anthropometry, fasting plasma glucose, 2-h plasma glucose, insulin resistance (HOMA-IR), adiponectin and ghrelin concentrations were measured at baseline and 4.1 +/- 0.9 years later. Multivariate analyses were used to explore the associations of HOMA-IR, adiponectin and ghrelin with weight change and glycaemia. Results The mean weight change was 2.6 +/- 5.5 kg. There were 114 incident cases of impaired glucose tolerance (IGT) and 35 cases of diabetes mellitus. Adiponectin was positively correlated with age and female sex (P-values < 0.01). After adjusting for age and sex, adiponectin and ghrelin were significantly correlated with weight at baseline and follow-up. However, they were not associated with weight change even after further adjustment for baseline weight. Adiponectin, but not ghrelin, was associated with 2-h glucose concentrations at follow-up even after adjusting for age, sex, HOMA-IR and BMI (P = 0.04). In the fully adjusted logistic regression model, adiponectin predicted incident IGT (OR 0.93; 95% CI: 0.87-0.99) and attenuated the effect of BMI on incident IGT. CONCLUSIONS: These longitudinal data show that adiponectin and ghrelin may not be causally involved in the development of obesity. However, adiponectin is independently associated with decreased risk of incident IGT.

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. RESULTS: Compared to the controls, T2DM patients had lower erythrocyte GSH concentrations (0.90 ± 0.42 vs. 0.35 ± 0.30 mmol/L; P = 0.001) and absolute synthesis rates (1.03 ± 0.55 vs. 0.50 ± 0.69 mmol/L/day; P = 0.01), but not fractional synthesis rates (114 ± 45 vs. 143 ± 82%/day; P = 0.07). The magnitudes of changes in patients with complications were greater for both GSH concentrations and absolute synthesis rates (P-values ≤ 0.01) compared to controls. There were no differences in GSH concentrations and synthesis rates between T2DM patients with and without complications (P-values > 0.1). Fasting glucose and HbA1c did not correlate with GSH concentration or synthesis rates (P-values > 0.17). CONCLUSIONS: Compared to non-diabetic controls, patients with T2DM have glutathione deficiency, especially if they have microvascular complications. This is probably due to reduced synthesis and increased irreversible utilization by non-glycemic mechanisms.

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. This report examines factors associated with item non-response and study efficiency in a national health survey in a developing Caribbean island. METHODS: A national sample of participants aged 15-74 years was selected in a multi-stage sampling design accounting for 4 health regions and 14 parishes using enumeration districts as primary sampling units. Means and proportions of the variables of interest were compared between various categories. Non-response was defined as failure to provide an analyzable response. Linear and logistic regression models accounting for sample design and post-stratification weighting were used to identify independent correlates of recruitment efficiency and item non-response. RESULTS: We recruited 2012 15-74 year-olds (66.2% females) at a response rate of 87.6% with significant variation between regions (80.9% to 97.6%; p < 0.0001). Females outnumbered males in all parishes. The majority of subjects were recruited in a single visit, 39.1% required multiple visits varying significantly by region (27.0% to 49.8% [p < 0.0001]). Average interview time was 44.3 minutes with no variation between health regions, urban-rural residence, educational level, gender and SES; but increased significantly with older age category from 42.9 minutes in the youngest to 46.0 minutes in the oldest age category. Between 15.8% and 26.8% of persons did not provide responses for the number of sexual partners in the last year. Women and urban residents provided less data than their counterparts. Highest item non-response related to income at 30% with no gender difference but independently related to educational level, employment status, age group and health region. Characteristics of non-responders vary with types of questions. CONCLUSION: Informative health surveys are possible in developing countries. While survey response rates may be satisfactory, item non-response was high in respect of income and sexual practice. In contrast to developed countries, non-response to questions on income is higher and has different correlates. These findings can inform future surveys.

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. Anthropometry, glucose tolerance, insulin levels, blood pressure and urinary isoprostane concentration were measured at baseline and follow-up. IS and BCF were estimated by the method of homeostasis assessment. Fifty-two individuals who progressed to IGT or diabetes and 44 age, sex and body mass index (BMI) matched controls were studied. Progression to glucose intolerance was significantly related with baseline BCF (p< or =0.01), but not isoprostane levels or IS. Glucose concentrations (fasting and 2 h) on follow-up were significantly correlated to baseline IS, baseline BCF, follow-up IS and follow-up BCF (p-values<0.05). In multiple regression analysis, only follow-up IS and BCF (p-values< or =0.001) independently predicted fasting glucose and 2h glucose levels at follow-up. Isoprostanes were not significantly associated with IS or BCF (p-values>0.1). We concluded that isoprostanes may not be causally involved in the development of glucose intolerance, insulin resistance or deteriorating BCF.

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. A secondary aim was to determine any associations between maternal nutritional status and cognition. STUDY DESIGN AND SUBJECTS: Subjects were participants in a prospective cohort study of developmental origins of adult disease. Eligible subjects were aged 6-8 years at their next scheduled visit to the study clinic and their mothers had abdominal ultrasound measurements at 14, 25 and 35 weeks gestation. 186 of 264 eligible children attended the clinic and were tested. OUTCOME MEASURES: Raven's Progressive Matrices (reasoning ability), Peabody Picture Vocabulary Test (receptive vocabulary) and Digit Span Forwards (auditory working memory). RESULTS: In multiple regression analyses controlling for children's age and socioeconomic status, head circumference at 14 weeks gestation was significantly associated with reasoning ability. The difference between the lowest and highest quartiles was equivalent to 0.4 S.D. No other significant associations with fetal growth were found. Maternal weight gain was not associated with cognitive scores; however, change in triceps skinfold between 25 and 35 weeks gestation was positively associated with reasoning ability and remained a significant predictor when included in the regression model. CONCLUSIONS: There were few associations between growth in utero and cognition. Growth in head circumference in early gestation and maternal nutrition in late gestation may affect later cognitive ability. Further research in this area is needed to confirm these results.

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. Mean serum calcium concentrations was higher among cases (2.32 ± 0.19 mmol/L) than controls, (2.27 ± 0.30 mmol/L) (P = 0.023) however, there were no differences in 25(OH)D by cancer status (cases, 33.67 ± 12.71 ng/mL; controls (32.25 ± 12.59 ng/mL). Serum calcium was not correlated with 25(OH)D (partial correlation: r, 0.06; P = 0.287). Multivariable-adjusted models showed a positive linear relationship between PCa and serum calcium (OR, 1.12; CI, 1.00-1.25 per 0.1 nmol/L). Serum 25(OH)D concentration also showed a positive association with PCa (OR, 1.23; CI, 1.01-1.49 per 10 ng/mL). The odds of PCa in men with serum 25(OH)D tertile 2 was OR, 2.18; CI, 1.04-4.43 and OR, 2.47 CI, 1.20-4.90 for tertile 3 (P(trend) = 0.013). Dietary intakes of calcium showed no relationship with PCa. Despite the strong relationship between serum calcium and vitamin D the mechanism by which each affects prostate cancer risk in men of African ancestry needs additional investigation.

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. In the second and third trimesters, maternal IGF-I was significantly correlated (P < 0.005) with maternal body mass index and triceps skinfold thickness. Maternal IGFBP-1 and -2 had an inverse correlation (P < 0.0001), with maternal anthropometry. Maternal IGF-I at 35 wk, and fetal IGF-I by cord blood were significantly correlated with birth weight (P = 0.001 and 0.048, respectively). IGFBP-1 in the third trimester and cord blood were negatively correlated with birth weight (P = 0.012 and 0.002). In multiple regression analyses, maternal IGF-I at 35 wk, fetal IGF-I, maternal weight at the first antenatal visit, gender, and gestational age were significant independent factors in the determination of birth weight. In conclusion, maternal IGF-I levels, especially during late pregnancy, positively influence birth weight.

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. Data were collected between 2005 and 2007 when participants were 18-20 years old. All participants completed an interviewer administered questionnaire and had anthropometric and blood pressure (BP) measurements performed. Fasting blood samples were collected for measurement of glucose, lipids, and hsCRP. Logistic regression models were used to identify factors independently associated with high hsCRP. RESULTS: Analyses included 342 men and 404 women with mean age 18.8 ± 0.6 years. Approximately 15% of the participants had high risk hsCRP (>3 mg/L), with a higher prevalence among women (20 vs. 9%; p < 0.001). The prevalence of elevated hsCRP increased with body mass index category, high waist circumference (WC), high triglycerides, low high density lipoprotein, and lower parental education among women, but only for high WC and lower parental education among men. In logistic regression models controlling for sex and parental education, high WC was associated with significantly higher odds of high hsCRP (OR 7.8, 95% CI 4.8-12.9, p < 0.001). In a similar model, high hsCRP was also associated with the number of metabolic syndrome components. Compared to participants with no metabolic syndrome component, having one metabolic syndrome component was associated with a twofold higher odds of high hsCRP (OR 2.2, 95% CI 1.3-3.8, p = 0.005), while having three components was associated with a 14-fold higher odds of high hsCRP (OR 13.5, 95% CI 2.4-76.0, p < 0.001). CONCLUSION: High hsCRP is common among Jamaican young adults and is strongly associated with central obesity and the number of metabolic syndrome components.

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. Serum folate was measured by an immunoassay method and genomic DNA evaluated for MTHR (C677T and A1298C), MTRR A66G, and MTR A2756G polymorphisms. Mean serum folate concentration was higher among cases (12.3 ± 4.1 nmol/L) than controls (9.7 ± 4.2 nmol/L). Serum folate concentration showed a positive association with prostate cancer (OR, 4.41; CI, 2.52-7.72 per 10 nmol/L) regardless of grade. No interactions were observed between genotype and folate concentration, but a weak gene effect was observed for MTHFR A1298C and low-grade prostate cancer. Larger studies to investigate the role of gene-gene/gene-diet interactions in Black men are needed.

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.

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. Diet was assessed by food frequency questionnaire. RESULTS: Factor analysis yielded four dietary patterns: (i) a "healthy" pattern of vegetables, fruits and peas and beans, (ii) a "carbohydrate" pattern with high loadings for white bread and refined cereals, (iii) "sugary foods and sweet baked products" pattern and (iv) a "organ meat and fast food pattern" with high loadings for high fat dessert, organ meat, fast food and salty snacks.Logistic regressions with the individual dietary patterns controlling for potential confounders showed no association between any of the food patterns and risk of prostate cancer. The healthy pattern showed an inverse non-significant association, whereas the carbohydrate pattern was positively and insignificantly related to prostate cancer. Analysis of all food patterns adjusting for each other revealed no association between food patterns and the risk of prostate cancer. CONCLUSION: Dietary patterns identified in our sample were not associated with risk of prostate cancer. Further investigations that better define cancer-free subjects and dietary measurements are needed to examine diet and prostate cancer outcomes.

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 9.6 years) with higher blood pressures and 20 children with lower blood pressures were chosen from a prospective study of 569 mothers and children in Jamaica. Daytime salivary cortisol profiles were collected in the children and their mothers. The mothers were also assessed for features of the metabolic syndrome. Children with higher BP had higher mean morning salivary cortisol concentrations than those with lower BP (7.9 S.D. 1.9 vs. 4.5 S.D. 2.4nmol/l; p=0.03). Their mothers also had increased morning salivary cortisol concentrations (9.9 S.D. 1.8 vs. 5.5 S.D. 2.5nmol/l; p=0.02), but no changes in fasting glucose, insulin, lipids, BP or adiposity. Maternal and offspring cortisol concentrations correlated significantly (r=0.465, p=0.004). Maternal cortisol concentrations were significantly associated with the child's BP. We conclude that Afro-Caribbean children with higher BP have higher morning salivary cortisol concentrations. The children's cortisol concentrations correlate significantly with the mother's cortisol concentrations. These findings suggest that the HPAA may play a role in the development of raised BP in Afro-Caribbean people.