Higher total homocysteine concentrations and lower folate concentrations in premenopausal black women than in premenopausal white women

Dietary riboflavin intake in relation to psychological disorders in Iranian adults: an observational study

Findings of earlier investigations on association between dietary riboflavin intake and psychological disorders are contradictory. Therefore, the relation between dietary riboflavin intake and depression, anxiety, and psychological distress was assessed in Iranian adults. In this cross-sectional study, dietary intakes of 3362 middle-aged adults were collected using a validated dish-based food frequency questionnaire. Daily intake of riboflavin for each participant was calculated by summing up the amount of riboflavin contents of all foods and dishes. Hospital Anxiety and Depression Scale (HADS) and General Health Questionnaire (GHQ), as validated questionnaires among Iranians, have been applied to assess depression, anxiety, and psychological distress. After considering potential confounders, adults in the top energy-adjusted quartile of riboflavin intake, compared to the bottom quartile, had decreased odds of depression (OR = 0.66; 95%CI 0.49, 0.88), anxiety (OR = 0.64; 95%CI 0.44, 0.94) and high psychological distress (OR = 0.65; 95%CI 0.48, 0.89). Stratified analysis by sex revealed that men in the forth quartile of riboflavin intake, compared with those in the first quartile, had respectively 51 and 55% lower odds of depression (OR = 0.49; 95%CI 0.29, 0.83) and anxiety (OR = 0.45; 95%CI 0.21, 0.95). In women, riboflavin intake was significantly associated with lower odds of psychological distress (OR = 0.67; 95%CI 0.46, 0.98). An inverse relation was observed between dietary riboflavin intake and chance of psychological disorders in Iranian adults. High intake of riboflavin decreased the chance of depression and anxiety in men and high psychological distress in women. More prospective studies are needed to confirm these findings.

Dietary B Vitamins and Depression in Persons with Human Immunodeficiency Virus Infection: The Positive Living with HIV (POLH) Study

B vitamins have beneficial roles in mental health functional impairments; however, research on the role of B vitamins in depression among HIV-infected persons is limited. This study assessed the association between dietary B vitamin intake and depressive symptoms in a cohort of HIV-infected persons. A cross-sectional survey was conducted among 314 HIV-infected persons (180 men and 134 women) aged 18 to 60 y residing in the Kathmandu, Nepal. The Beck Depression Inventory-I was used to measure depression, with a cutoff score of 20 or higher. Dietary intake was assessed using two nonconsecutive 24-h dietary recalls. The relationships between B vitamins and depressive symptoms were assessed using multiple logistic regression analysis. Twenty-six percent participants (men: 23%; women: 29%) were depressed. More than two thirds of participants' B vitamins intake were below the estimated average requirements (EAR) level. Low intake of riboflavin was associated with an increased risk of depression in women but not in men. Multivariate OR (95% CI) for depression in the first, second, and third tertiles of riboflavin in total participants were 1 (reference), 0.87 (0.46-1.64), and 0.49 (0.24-0.98), respectively (p for trend=0.048) and in women were 1 (reference), 0.94 (0.36-2.40), and 0.23 (0.07-0.77), respectively (p for trend=0.020). No clear associations were seen between other B vitamins and depressive symptoms in either sex. Low intake of riboflavin was independently associated with an increased risk of depressive symptoms in all participants and in HIV-infected women. Further prospective studies are warranted to confirm the role of vitamin B vitamins in depressive symptoms among HIV-infected persons.

Racial/ethnic disparity in the associations of smoking status with uncontrolled hypertension subtypes among hypertensive subjects

Background

Racial/ethnic differences in the associations of smoking with uncontrolled blood pressure (BP) and its subtypes (isolated uncontrolled systolic BP (SBP), uncontrolled systolic-diastolic BP, and isolated uncontrolled diastolic BP (DBP)) have not been investigated among diagnosed hypertensive subjects.

Methods

A sample of 7,586 hypertensive patients aged ≥18 years were selected from the National Health and Nutrition Examination Survey 1999–2010. Race/ethnicity was classified into Hispanic, non-Hispanic white, and non-Hispanic black. Smoking was categorized as never smoking, ex-smoking, and current smoking. Uncontrolled BP was determined as SBP≥140 or DBP≥90 mm Hg. Isolated uncontrolled SBP was defined as SBP≥140 and DBP<90 mm Hg, uncontrolled SDBP as SBP≥140 and DBP≥90 mm Hg, and isolated uncontrolled DBP as SBP<140 and DBP≥90 mm Hg. Adjusted odds ratios (ORs) with 95% confidence intervals (CIs) of uncontrolled BP and its subtypes were calculated using weighted logistic regression models.

Results

The interaction effect of race and smoking was significant after adjustment for the full potential confounding covariates (Adjusted p = 0.0412). Compared to never smokers, current smokers were 29% less likely to have uncontrolled BP in non-Hispanic whites (OR = 0.71, 95% CI = 0.56–0.90), although the likelihood for uncontrolled BP is the same for smokers and never smokers in Hispanics and non-Hispanic blacks. Current smokers were 26% less likely than never smokers to have isolated uncontrolled SBP in non-Hispanic whites (OR = 0.74, 95% CI = 0.58–0.95). However, current smoking is associated with an increased likelihood of uncontrolled systolic-diastolic BP in non-Hispanic blacks, and current smokers in this group were 70% more likely to have uncontrolled systolic-diastolic BP than never smokers (OR = 1.70, 95% CI = 1.10–2.65).

Conclusion

The associations between current smoking and uncontrolled BP differed over race/ethnicity. Health practitioners may need to be especially vigilant with non-Hispanic black smokers with diagnosed hypertension.

Dietary B Vitamins and Serum C-Reactive Protein in Persons With Human Immunodeficiency Virus Infection: The Positive Living With HIV (POLH) Study

BACKGROUND

B vitamins may have beneficial roles in reducing inflammation; however, research on the role of B vitamins in inflammation among HIV-infected persons is lacking.

OBJECTIVE

This study assessed the association between B vitamins and serum C-reactive protein (CRP) concentrations in HIV-infected persons.

METHODS

A cross-sectional survey was conducted among 314 HIV-infected persons (180 men and 134 women) aged 18 to 60 years residing in the Kathmandu, Nepal. High-sensitive and regular serum CRP concentrations were measured by the latex agglutination nephelometry and latex agglutination turbidimetric method, respectively. Dietary intake was assessed using 2 nonconsecutive 24-hour dietary recalls. The relationships between B vitamins and serum CRP concentrations were assessed using multiple regression analysis.

RESULTS

The multivariate-adjusted geometric mean of serum CRP concentrations was significantly decreased with an increasing B vitamins intake across quartiles of niacin (P for trend = .007), pyridoxine (P for trend = .042), and cobalamin (P for trend = .037) in men. In men, the mean serum CRP concentrations in the highest quartiles of niacin, pyridoxine, and cobalamin were 63%, 38%, and 58%, respectively, lower than that in the lowest quartile. In women, the mean serum CRP concentrations in the highest quartiles of riboflavin (P for trend = .084) and pyridoxine (P for trend = .093) were 37% and 47%, respectively, lower than that in the lowest quartile.

CONCLUSION

High intake of niacin, pyridoxine, or cobalamin was independently associated with decreased serum CRP concentrations among HIV-infected men. Further prospective studies are warranted to confirm the role of B vitamins in inflammation among HIV-infected persons.

Microalbuminuria, macroalbuminuria and uncontrolled blood pressure among diagnosed hypertensive patients: the aspect of racial disparity in the NHANES study

Accumulating evidence reveals that albuminuria may exacerbate uncontrolled blood pressure (BP) in hypertensive patients. However, racial differences in the associations of albuminuria with uncontrolled BP among diagnosed hypertensives have not been evaluated. A total of 6147 diagnosed hypertensive subjects aged ≥ 18 years were collected from the National Health and Nutrition Examination Survey 1999-2008 with stratified multistage sampling designs. Odds ratios (ORs), relative ORs and 95% confidence intervals (CIs) in uncontrolled BP, and the different effects of microalbuminuria and macroalbuminuria on continuous BP were estimated using weighted logistic models and linear regression models. Hypertensive subjects with microalbuminuria and macroalbuminuria were more likely to have uncontrolled BP and higher average systolic BP (SBP) in all individual racial groups. Microalbuminuria was associated with isolated uncontrolled SBP in non-Hispanic blacks and whites, and macroalbuminuria was associated with isolated uncontrolled SBP and diastolic BP (DBP) and high average DBP only in non-Hispanic blacks. Compared with non-Hispanic whites, non-Hispanic blacks and Mexicans had lower associations of microalbuminuria with uncontrolled BP (relative OR = 0.68, 95% CI = 0.48-0.97 for blacks vs whites; relative OR = 0.62, 95% CI = 0.42-0.93 for Mexicans vs. whites) and isolated uncontrolled SBP (relative OR = 0.62, 95% CI = 0.43-0.90 for blacks vs. whites; relative OR = 0.45, 95% CI = 0.29-0.71 for Mexicans vs. whites). The association of microalbuminuria with uncontrolled BP was lower in non-Hispanic blacks and Mexicans than in non-Hispanic whites. Health providers need to improve care for mildly elevated albumin excretion rates in non-Hispanic white hypertensive patients while maintaining the quality of care in non-Hispanic blacks and Mexicans.

Racial disparities in cardiovascular risk factors among diagnosed hypertensive subjects

Racial disparities in cardiovascular disease (CVD) have become a matter of national concern. We investigated racial disparities and trends in glycosylated hemoglobin, high-density lipoprotein (HDL), C-reactive protein, plasma homocysteine, albuminuria, and other risk factors among 4758 diagnosed hypertensive subjects age 18 years or older from the National Health and Nutrition Examination Survey, 1999-2006. Compared with non-Hispanic whites, Hispanics, and non-Hispanic blacks were more likely to have uncontrolled blood pressure (BP) (Hispanics odds ratio [OR]: 1.58, 95% confidence interval [CI]: 1.21-2.07; blacks OR: 1.42, 95% CI: 0.21-1.67), elevated glycosylated hemoglobin (Hispanics OR: 2.70, 95% CI: 1.89-3.87; blacks OR: 2.17, 95% CI: 1.70-2.77), albuminuria (Hispanics OR: 2.36, 95% CI: 1.71-3.27; blacks OR: 1.80, 95% CI: 1.47-2.20), and less likely to have central obesity (Hispanics OR: 0.68, 95% CI: 0.51-0.91; blacks OR: 0.70, 95% CI: 0.58-0.84). Blacks had lower risks of elevated serum cholesterol (OR: 0.81, 95% CI: 0.67-0.98) and low HDL (OR: 0.76, 95% CI: 0.61-0.94) than whites. The risk of high serum homocysteine was lower in Hispanics and higher in blacks compared with whites (Hispanics OR: 0.64, 95% CI: 0.46-0.90; blacks OR: 1.36, 95% CI: 1.14-1.63). These results highlight the need for targeted interventions to aggressively treat uncontrolled BP, elevated glycosylated hemoglobin in Hispanic and black hypertensive subjects, and high serum homocysteine in blacks, to reduce disparities in CVD risk factors and CVD-associated morbidity and mortality.

Peripheral arterial disease: current perspectives and new trends in management

Peripheral arterial disease (PAD) is defined as an arterial brachial index (ABI) of < or =0.90 in the lower extremities and results from a narrowing of the arteries as a result of progressive atherosclerosis. PAD affects 12-20% of Americans aged 65 years or older; however, most are asymptomatic and many do not seek treatment. Improved awareness and education in both the general population and among health care providers about these modifiable risk factors has the potential to improve general health and decrease morbidity and mortality secondary to atherosclerotic vascular disease.

Demographic, lifestyle, and health characteristics and serum B vitamin status are determinants of plasma total homocysteine concentration in the post-folic acid fortification period, 1999-2004

Elevated circulating total homocysteine (tHcy) concentrations are related to increased risk for cardiovascular disease. Folic acid fortification resulted in a significant decrease in circulating tHcy in the United States. In the post-folic acid fortification period, associations between plasma tHcy and demographic, health, and lifestyle factors and B vitamin status were investigated. Data from the 3 recent NHANES cycles (1999-2004) were used to study the associations among plasma tHcy and sex, race/ethnicity, age, BMI, blood pressure (BP), serum creatinine, serum cotinine, vitamin/mineral supplement use, and folate and cobalamin status in 16,254 persons (8329 men, 7925 women). Multivariate-adjusted plasma tHcy was approximately 9.7% higher in men than in women (P < 0.0001), approximately 5.3% higher in non-Hispanic whites than in non-Hispanic blacks (P < 0.0001), approximately 64.5% higher in individuals aged >or=60 y than in individuals aged <20 y (P < 0.0001), and approximately 5% higher in supplement nonusers than in supplement users (P < 0.0001). Persons in the 4th quartile for serum creatinine, serum cotinine, systolic BP, and serum methylmalonic acid (MMA) had approximately 36.1, approximately 13.4, approximately 5.6, and approximately 16.2%, respectively, higher tHcy than those in the 1st quartile (P < 0.0001). Plasma tHcy was inversely associated with serum folate (P < 0.0001), RBC folate (P < 0.0001), and serum cobalamin (P < 0.0001). In the post-folic acid fortification period, sex, race/ethnicity, age, systolic BP, supplement use, RBC folate, and serum creatinine, cotinine, folate, and cobalamin are significant determinants of plasma tHcy. Serum MMA was strongly associated with plasma tHcy.

Population reference values for plasma total homocysteine concentrations in US adults after the fortification of cereals with folic acid

BACKGROUND

Folic acid fortification has resulted in a dramatic increase in folate intake in the United States. Folate intake is inversely associated with circulating total homocysteine (tHcy). Elevated tHcy is directly associated with cardiovascular disease risk.

OBJECTIVE

The aim of this study was to present the distribution of plasma concentrations of tHcy in US adults by using data from nationally representative sample surveys conducted since folic acid fortification was implemented.

DESIGN

Data from the National Health and Nutrition Examination Surveys from 1999-2001 and 2001-2002 were used to study tHcy distribution by age, sex, and race-ethnicity in 9196 persons.

RESULTS

Plasma concentrations of tHcy were higher in men than in women and in older persons than in younger persons. In those aged 19-30, 31-50, and 51-70 y but not in those aged >70 y, men had significantly (P < 0.0001) higher mean plasma concentrations of tHcy than did women. A race-ethnicity difference in plasma tHcy existed only in persons aged >70 y. Non-Hispanic blacks aged >70 y had significantly (P < 0.05) higher tHcy concentrations than did non-Hispanic white or Mexican American or Hispanic subjects in the same age group. Age-adjusted plasma tHcy concentrations did not differ significantly between non-Hispanic white (8.39 micromol/L), non-Hispanic black (8.92 micromol/L), and Mexican American or Hispanic (8.12 micromol/L) subjects. The rate of increase in plasma tHcy was greater in non-Hispanic blacks aged >/=50 y than in persons of similar age but of other races-ethnicities.

CONCLUSIONS

These plasma tHcy data reflect the effects of folic acid fortification. Sex, age, and race-ethnicity differences persist in plasma tHcy concentrations.

The prognostic value of hemoglobin change after initiating androgen-deprivation therapy for newly diagnosed metastatic prostate cancer: A multivariate analysis of Southwest Oncology Group Study 8894

BACKGROUND

The objective of this study was to characterize changes in hemoglobin (HGB) levels after the initiation of androgen-deprivation therapy (ADT) in patients with previously untreated, metastatic prostate cancer who were enrolled in a large clinical trial.

METHODS

The multivariate associations between 3-month change in HGB and baseline characteristics were evaluated with a linear regression model. The associations between 3-month change in HGB level and time-to-event outcomes, including overall survival and progression-free survival, were evaluated by using proportional hazards regression models.

RESULTS

Quartiles of baseline HGB levels were < or =12.0 g/dL, from 12.1 to 13.7 g/dL, from 13.8 to 14.7 g/dL, and >14.7 g/dL. Overall, 3 months after initiating ADT, the mean HGB level declined 0.54 g/dL (standard deviation [SD], 1.68 g/dL); however, the mean HGB level increased by 0.99 g/dL (SD, 1.83 g/dL) in patients who had baseline HGB levels <12 g/dL and decreased 1.04 g/dL (SD, 1.28 g/dL) in patients who had baseline HGB levels > or =12 g/dL. After adjusting for potential confounders, including baseline HGB level, a decline in HGB after 3 months of ADT was associated independently with shorter survival (hazards ratio [HR], 1.10 per 1 g/dL decline; P = .0035) and shorter progression-free survival (HR, 1.08 per 1 g/dL decline; P = .013). An unexpected finding was that the effect of baseline HGB on overall and progression-free survival varied significantly by race.

CONCLUSIONS

In a sample of men with newly diagnosed, metastatic prostate cancer, a decline in HGB level after 3 months of ADT was associated with shorter survival and progression-free survival after adjusting for disease status and other baseline covariates. Although race alone was not a strong predictor of death or disease progression, the effect of the baseline HGB level on overall and progression-free survival varied significantly by race.

Ethnicity and peripheral arterial disease: the San Diego Population Study

BACKGROUND

Previous studies have indicated higher rates of peripheral arterial disease (PAD) in blacks than in non-Hispanic whites (NHWs), with limited information available for Hispanics and Asians. The reason for the PAD excess in blacks is unclear.

METHODS AND RESULTS

Ethnic-specific PAD prevalence rates were determined in a randomly selected defined population that included 4 ethnic groups; NHWs, blacks, Hispanics, and Asians. A total of 2343 participants aged 29 to 91 years were evaluated. There were 104 cases of PAD (4.4%). In weighted logistic models with NHWs as the reference group and containing demographic factors only, blacks had a higher PAD prevalence than NHWs (OR=2.30, P<0.024), whereas PAD rates in Hispanics and Asians, although somewhat lower, were not significantly different from NHWs. Blacks had significantly more diabetes and hypertension than NHWs and a significantly higher body mass index. Inclusion of these variables and other PAD risk factors in the model did not change the effect size for black ethnicity (OR=2.34, P=0.048). A model containing interaction terms for black ethnicity and each of the other risk factors revealed no significant interaction terms, which indicates no evidence that blacks were more "susceptible" than NHWs to cardiovascular disease risk factors.

CONCLUSIONS

Black ethnicity was a strong and independent risk factor for PAD, which was not explained by higher levels of diabetes, hypertension, and body mass index. There was no evidence of a greater susceptibility of blacks to cardiovascular disease risk factors as a reason for their higher PAD prevalence. Thus, the excess risk of PAD in blacks remains unexplained and requires further study.

Population references for plasma total homocysteine concentrations for U.S. children and adolescents in the post-folic acid fortification era

Folate intake is inversely related to circulating total homocysteine (tHcy) concentrations. Elevated tHcy is a risk factor for vascular diseases. The objectives of this study were to present plasma tHcy distributions and investigate the association between tHcy and sex, age, and race-ethnicity in U.S. children and adolescents (3264 boys and 3197 girls) using data from the National Health and Nutrition Examination Surveys, 1999-2000 and 2001-2002 conducted in the post-folic acid fortification era. Plasma tHcy was higher in boys than in girls (P < 0.0001), and higher in older children (16-18 y old) than in younger children (3-15 y old) (P < 0.0001). The difference in plasma tHcy between boys and girls was greater in the 16- to 18-y-old group than in any other age group studied (P < 0.05). Age-adjusted plasma tHcy concentrations were approximately 6.8, approximately 10.5, and approximately 8.8% higher in boys than in girls in non-Hispanic White (NHW), non-Hispanic Black (NHB), and Mexican American/Hispanic (MA/H) children, respectively. Sex- and age-adjusted plasma tHcy concentrations (geometric means +/- SE) were 5.04 +/- 0.05, 5.01 +/- 0.06, and 4.99 +/- 0.06 micromol/L in the NHW, NHB, and MA/H groups, respectively. Race-ethnicity was not related to plasma tHcy in age-adjusted analysis for boys (P < 0.77) and girls (P < 0.26), and in sex- and age-adjusted analysis (P < 0.38) for all children. The plasma tHcy concentrations begin to rise between ages 8 and 11 y, and the age-related increase is greater in boys than in girls.

Frequent consumption of milk, yogurt, cold breakfast cereals, peppers, and cruciferous vegetables and intakes of dietary folate and riboflavin but not vitamins B-12 and B-6 are inversely associated with serum total homocysteine concentrations in the US population

BACKGROUND

Elevated circulating total homocysteine (tHcy) is an independent risk factor for vascular diseases.

OBJECTIVE

We investigated the relation between dietary intakes and serum tHcy in the US population.

DESIGN

Data from the third National Health and Nutrition Examination Survey (1988-1994) were used to investigate the associations between food consumption frequency and dietary B vitamin intakes and serum tHcy in 5996 persons.

RESULTS

Multivariate-adjusted tHcy concentrations were approximately 15.2% higher in subjects who never consumed milk than in those who consumed milk >30 times/mo, approximately 6.4% higher in subjects who never consumed yogurt than in those who consumed yogurt >15 times/mo, approximately 7.4% higher in subjects who never consumed cold breakfast cereals than in those who consumed cold breakfast cereals >30 times/mo, approximately 6.3% higher in subjects who never consumed peppers (includes red, yellow, green, and hot chili peppers) than in those who consumed peppers >30 times/mo, and approximately 16.5% higher in subjects who never consumed cruciferous vegetables than in those who consumed cruciferous vegetables >30 times/mo. Consumption of citrus fruit and juices, cheese, meats, coffee, or tea had no significant association with tHcy. Folate (beta=-0.0017, P for trend=0.004) and riboflavin (beta=-0.2851, P for trend=0.027), but not vitamin B-6 (beta=0.0505, P for trend=0.70) and cobalamin (beta=-0.0035, P for trend=0.58), were inversely related to serum tHcy after adjustment for confounders.

CONCLUSIONS

In this population-based study, milk, yogurt, cold breakfast cereals, peppers, and cruciferous vegetables were inversely related to serum tHcy. This association may be explained by increased intakes of folate and riboflavin.

Homocysteine and folic acid are inversely related in black women with preeclampsia

Black women have an increased risk of preeclampsia compared with white women. Plasma homocysteine is increased in preeclampsia. Homocysteine concentrations are affected by nutritional deficiencies, particularly decreased folic acid and B12, leading to increased homocysteine. Previous studies have reported racial differences in nutritional intake including folic acid. Therefore, we investigated whether there were racial differences in plasma homocysteine, folic acid, and vitamin B12 among women with preeclampsia. We tested for an association between homocysteine and folic acid and B12, and we hypothesized an inverse relationship of homocysteine and folic acid in preeclampsia, more so in black women in whom preeclampsia developed. Black women with preeclampsia (n=26) had elevated homocysteine concentrations (8.7+/-1.4 micromol/L) compared with black women with normal pregnancy (n=52, 7.6+/-0.5 micromol/L), white women with preeclampsia (n=34, 7.5+/-0.6 micromol/L), and white women with normal pregnancy (n=48, 5.5+/-0.3 micromol/L). Folic acid concentrations were lower in black women (14.1+/-0.8 ng/mL) compared with white women (18.5+/-0.9 ng/mL, P<0.01). However, plasma homocysteine was inversely related to folic acid only among black women with preeclampsia (r=-0.23, P=0.01). These racial differences may have implications for the higher rates of preeclampsia in this group and may have long-term implications for future cardiovascular risk. Racial differences in diet, adherence to folic acid supplementation, or interactions of nutritional and maternal factors warrant further study by race and pregnancy status.

Demographic, health, lifestyle, and blood vitamin determinants of serum total homocysteine concentrations in the third National Health and Nutrition Examination Survey, 1988-1994

BACKGROUND

Elevated serum total homocysteine (tHcy) is an independent risk factor for vascular diseases.

OBJECTIVE

Associations between serum tHcy and demographics, health and lifestyle factors, and blood vitamin concentrations were investigated.

DESIGN

Data from the third National Health and Nutrition Examination Survey, 1988-1994 were used to examine associations in men (n = 2965) and women (n = 3580) between tHcy and age, sex, race-ethnicity, body mass index, systolic and diastolic blood pressures, alcohol consumption, supplement use, red blood cell (RBC) folate, and serum creatinine, folate, vitamin B-12, and cotinine (a measure of cigarette smoking).

RESULTS

The unadjusted mean tHcy was 21.5% ( approximately 1.9 micro mol/L) higher in men than in women, 11.8% ( approximately 1.1 micro mol/L) higher in non-Hispanic whites than in Mexican Americans, 42% ( approximately 3.7 micro mol/L) higher in persons aged > or = 70 y than in persons aged < 30 y, and 10.9% ( approximately 1.0 micro mol/L) higher in supplement nonusers than in supplement users. The tHcy concentration was negatively associated with serum folate (P < 0.0001 for trend), RBC folate (P < 0.0001 for trend), and serum vitamin B-12 (P < 0.0036 for trend) and was positively associated with alcohol consumption (P < 0.0001 for trend), serum cotinine (P < 0.0001 for trend), and systolic blood pressure (P < 0.0001 for trend). Consumption of hard liquor (but not of beer or wine) was positively associated with tHcy concentration (P < 0.0001 for trend).

CONCLUSIONS

In this population-based study, the significant predictors of tHcy concentration were sex, age, race-ethnicity, serum creatinine, systolic blood pressure, body mass index, hard-liquor consumption, smoking, supplement use, serum folate, RBC folate, and serum vitamin B-12.

Premenopausal black women are uniquely at risk for coronary heart disease compared to white women

Premenopausal black women have a two to threefold greater rate of coronary heart disease than premenopausal white women. This study was designed to provide greater insight into the reasons for this difference which is currently unclear. Coronary heart disease risk factors were compared in 100 black and 100 white, healthy premenopausal women, ages 18-45 years, and of relatively advantaged socioeconomic status. Compared to white women, black women had a higher body mass index (32.0±9.2 vs. 29.0±9.4 kg/m2, p=0.021), and higher systolic (124±17 vs. 115±14 mm Hg, p<0.0001) and diastolic (79±14 vs. 75±11 mm Hg, p=0.048) blood pressures. The mean plasma lipoprotein(a) concentration was markedly higher in the black women (40.2±31.3 mg/dL) than in the white women (19.2±23.7 mg/dL, p<0.0001). The plasma total homocysteine level was also higher in the black women (8.80±3.38 vs. 7.81±2.58 mmol/L, p=0.013). The black women, however, had lower plasma triglyceride levels (0.91±0.46 vs. 1.22±0.60 mmol/L, p<0.0001) and a trend toward higher high-density lipoprotein cholesterol levels (1.37±0.34 vs. 1.29±0.31 mmol/L, p=0.064) than the white women. Plasma total and low-density lipoprotein cholesterol levels were similar. Black women consumed more saturated fat and cholesterol. Rates of cigarette smoking and alcohol intake were low and similar between the races. In summary, compared to white women, black women had a higher mean body mass index, higher blood pressures, higher lipoprotein(a) and plasma total homocysteine levels, and greater consumption of saturated fat and cholesterol. The differences in coronary risk factors between these two premenopausal groups may explain the higher incidence of coronary heart disease in black women. (c) 2000 by CHF, Inc.

Nutrition, genetics, and risks of cancer

Dietary patterns, nutrients, and other constituents of food are major components of the environmental influences that contribute to risk for cancer, and the study of interactions between nutritional and genetic factors is a new and important area or research. This review describes the concepts and principles underlying this area of study and types of relationships between nutritional and genetic factors, and it provides examples of specific diet-gene interactions that are of current interest, with an emphasis on implications for cancer prevention and public health. Polymorphisms exist in the genes for the activating and conjugating metabolizing enzymes, and the induction of metabolizing enzyme activity by nutritional factors may result in either the activation of a carcinogen or the detoxification of a reactive intermediate metabolite. The relationship between the methylenetetrahydrofolate reductase gene and dietary folate is an example of a diet-gene interaction that involves a polymorphism in a vitamin metabolism gene, and the presence of the variant appears to influence both risk for cancer and folate requirements. Diet-gene interactions likely contribute considerably to the observed inter-individual variations in cancer risk in response to exposures to the nutritional factors that have the potential to promote or protect against cancer. Insights into mechanisms by which nutritional factors affect the process of carcinogenesis are provided by knowledge of the targeted gene function and enzyme activity. Increased knowledge in this area will allow a more refined approach to reducing risk for cancer, with diet interventions targeted toward individuals and subgroups that are genetically susceptible and responsive to the effects of nutritional factors.