The relationship between zinc and copper status and lipid levels in African-Americans.

Studies examining the role of zinc and copper nutriture as risk factors for cardiovascular disease in European Americans have produced conflicting results. This study assessed the associations between zinc and copper status and serum lipid levels in an adult African-American community. A cross-sectional study was conducted on 600 individuals (233 males, 367 females) from 25 to 65 yr of age using a random sampling design in a small city in Alabama. Anthropometric, dietary, and serum zinc, copper, and lipid measurements were made. The mean serum zinc and copper levels and dietary zinc intake were similar to that reported previously for European Americans. There were no significant associations between serum zinc, copper, or zinc/copper ratio and total serum cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), or triglyceride levels. For males, there was a small but significant association between dietary zinc and the total cholesterol/HDL-C ratio (r = -0.17, p = 0.03). Similarly, females taking either zinc supplements or a multivitamin including zinc had higher HDL-C values than nonsupplementing females. Further prospective studies of the relationship between zinc status and lipid levels in African Americans are needed to verify these results.

Increased risk of preterm delivery with elevated maternal alpha-fetoprotein and plasma zinc levels in African-American women.

BACKGROUND: This study evaluated the relationship of maternal serum alpha-fetoprotein (MSAFP) and plasma zinc levels (PZn) to pregnancy outcome. METHODS: The subjects for this investigation consisted of 917 African-American women, who on registration for prenatal care between 7-22 weeks gestational age (GA), had PZn levels determined and also had MSAFP recorded in their charts. RESULTS: MSAFP levels greater than the 90th percentile significantly increased the risk of PTD (adjusted odds ratio or AOR=2.5, 95% C.I.=1.5-4.2) but not of IUGR. There was no significant relationship between maternal PZn level and PTD or IUGR. When subjects were stratified by MSAFP levels, in women with MSAFP greater than the 90th percentile, the AOR for PTD was 4.0 (95% C.I.=1.2-13.5) for women with PZn levels greater than the median vs. those with PZn equal to or less than the median. In women with MSAFP equal to or less than the 90th percentile, there was no such difference. Multiple regression analyses, using GA at birth as the dependent variable, indicated an interaction between MSAFP and PZn levels. CONCLUSION: In this population, the adverse pregnancy outcome associated with elevated MSAFP was seen only in women with PZn levels greater than the median. The reason for this association is not currently apparent.

Determinants of zinc intake in low-income black and white pregnant women.

A prospective study was conducted to evaluate and compare the determinants of dietary zinc intake in black and white low-income pregnant women. The study population consisted of 1298 low-income women (70% Black, 30% White) who received prenatal care at University Hospital at the University of Alabama in Birmingham from 1985 to 1989. Various maternal characteristics were evaluated at the first prenatal visit. Two 24 h recalls were obtained at 18 and 30 wk of gestation to calculate the intakes of dietary zinc and other nutrients. Student's t test, chi2, Pearson correlation coefficients, and multiple regression analyses were used to compare and evaluate the determinants of zinc and other nutrient intakes in Black and White subjects. The mean prepregnancy body mass index and the mean intake of zinc, energy, and all the other nutrients except calcium were significantly higher in Black than in White subjects. There was a significant correlation between zinc and energy intake (r = 0.69, p = 0.001). Age, marital status, parity, socioeconomic status, smoking, and alcohol intake were not significant predictors of zinc or other nutrient intakes. After adjusting for energy intake, race was the only significant predictor of dietary zinc intake. Race and energy intake explained 24% of the variation in zinc intake. Results of this study indicate that after adjusting for other covariates, race and energy intakes are the only predictors of zinc intake in low-income pregnant women.

John Henryism, gender, and arterial blood pressure in an African American community.

OBJECTIVE: To examine the interaction between gender and John Henryism in relationship to arterial blood pressure in an African American community in the Southern United States. It was hypothesized that, within this specific social and cultural context, John Henryism would be associated with blood pressure differently for men and women. METHODS: A cross-sectional survey of 600 persons, aged 25 to 65, was conducted in the African American community of a small Southern city. John Henryism was assessed using the 12-item John Henryism Scale for Active Coping. Blood pressure was assessed by conventional methods. RESULTS: The interaction effect between gender and John Henryism was assessed as a cross-product term in ordinary least squares regression analysis using arterial blood pressure as the dependent variable, and with logistic regression using hypertension as the dependent variable. This interaction effect was significant (p < .05) in relation to systolic blood pressure and hypertension, with the effect evident (p < .07) in relation to diastolic blood pressure. For men, as John Henryism increases, blood pressure and the risk of hypertension increases. For women, as John Henryism increases, blood pressure and the risk of hypertension decreases. CONCLUSIONS: The association of the behavioral disposition of John Henryism with blood pressure is dependent on the gender of the individual. Men and women face differing cultural expectations and social structural constraints in this community. The sociocultural context modifies the meaning of the behavioral disposition, and hence its effects.

Culture, socioeconomic status, and coronary heart disease risk factors in an African American community.

In this paper, cultural influences are examined in the relationship between socioeconomic status and health. Cultural definitions of material lifestyles are investigated as a correlate of disease risk in an African American community in the rural South. A new technique--called "cultural consensus analysis"--is used to test for a cultural model of lifestyles indicative of success. Survey data are then used to operationalize the degree to which individuals adhere in their own behavior to that cultural model; this measure is referred to as "cultural consonance in lifestyle." Cultural consonance in lifestyle is more strongly associated with hypertension and smoking (but not serum lipids) than are conventional measures of socioeconomic status (occupation, income, and education). These results suggest that the extent to which individuals are unable to live in accordance with cultural norms regarding lifestyles may contribute to the risk of coronary heart disease in the African American community.

Plasma and erythrocyte zinc concentrations and their relationship to dietary zinc intake and zinc supplementation during pregnancy in low-income African-American women.

OBJECTIVE: To evaluate the effects of usual dietary intake of zinc and of zinc supplementation during pregnancy on plasma and erythrocyte zinc concentrations. DESIGN: A randomized, double-blind, placebo-controlled trial. SUBJECTS: Low-income African-American women (n = 580) assigned randomly to groups at 19 weeks of gestation. INTERVENTION: A daily dose of zinc (25 mg) or a placebo until delivery. MAIN OUTCOME MEASURES: Plasma, erythrocyte, and dietary zinc levels. STATISTICAL ANALYSES: Multiple regression and repeated measures analysis of variance. RESULTS: In both the placebo and the supplemented groups, when all subjects were grouped by usual dietary zinc intake above or below the median (12 mg/day), results were the same: Women with high dietary zinc intake had higher erythrocyte zinc levels at the time of randomization and at all subsequent measurements during pregnancy than those who had low dietary zinc intake (P < or = .06; difference not significant for zinc-supplemented group); no difference was observed for plasma zinc levels. On the other hand, when the subjects were stratified at the median by total daily zinc intake (usual dietary zinc + 25 mg zinc supplement) during pregnancy, a significant difference in plasma zinc levels (P < .005) was found between women with high total zinc intake (mean = 38 mg/day) and low total intake (mean = 13 mg/day) at 26, 32, and 38 weeks of gestation; however, no such differences were found in erythrocyte zinc levels. APPLICATIONS: These results should help dietitians and other health professionals better understand the expected changes in plasma and erythrocyte zinc levels during pregnancy, and the relationship between dietary and supplemental zinc and zinc nutriture.

The relationship between maternal dietary intake and infant birthweight.

BACKGROUND: Zinc and folate are important for fetal growth. However, the relationship between the dietary intake of these nutrients and pregnancy outcome is not settled. METHODS: A prospective study was conducted to ascertain the relationship between maternal dietary zinc and folate intake (n = 1398), serum zinc and folate levels (n = 289), and infant birthweight. Twenty-four hour recalls were used to measure energy, zinc, folate and other nutrient intakes at 18 and 30 weeks of gestation. Subjects in the study were offered daily folic acid (1.0 mg) and iron (60 mg as ferrous sulfate) at enrollment. RESULTS: Maternal zinc nutriture as assessed by serum and dietary intake was not associated with birthweight or length of gestation. There was a small but significant positive association between maternal folate intake and adjusted infant birthweight (beta = 0.05, p = 0.03). The indirect measures of maternal nutritional status including maternal pre-pregnancy weight (beta = 8.0, p = 0.0001) and weight gain during pregnancy (beta = 18.1, p = 0.0001) were stronger predictors of adjusted infant birthweight as compared to energy intake and intake of zinc and folate. An increase of 320, 290, and 48 g in infant birthweight was associated with the 90th-10th percentile difference for pre-pregnancy weight, weight gain during pregnancy, and folate intake respectively. CONCLUSION: These results indicate that pre-pregnancy weight and weight gain during pregnancy are both strong predictors of infant birthweight. Folate intake, although significantly associated with birthweight, was a weak predictor while maternal intake of zinc and other nutrients was not associated with birthweight.

Factors influencing plasma zinc levels in low-income pregnant women.

Plasma zinc (Zn) concentrations were measured in 4376 indigent women (86% African-American), at at mean (+/- SD) gestational age of 15 (+/- 7.8) wk to determine the relationship between various maternal characteristics and plasma Zn levels during pregnancy. Mean Plasma An levels were lower in African-American women than in Caucasian women, in multiparous women than in primiparous women, and in women with body weight > 69.9 kg than in those with body weight < or = 69.9 kg (p < or = 0.001 for each comparison). There were no significant differences related to maternal age, marital status, education, or smoking habit. Multiple regression analysis, including maternal prepregnancy weight, race, age, parity, smoking habit, education, and marital status indicated that race, parity, and pregnancy weight were significantly associated with maternal plasma Zn levels, adjusted for gestational age. Maternal race was the best predictor of plasma Zn concentrations among the population of pregnant women studied A significant proportion of variance in maternal plasma Zn levels. remained unexplained after taking into account various maternal characteristics. The reasons for lower plasma Zn levels in African-American women, compared to Caucasian women, during pregnancy are unknown.

The relationship between maternal serum zinc levels during pregnancy and birthweight.

A retrospective follow-up study to ascertain the relationship between the level of serum zinc and its rate of change during gestation and birthweight was conducted in 476 women of lower socioeconomic status. Serum zinc concentrations measured at approximately 16 (early) and 32 weeks (later) in gestation were both found to be significant predictors of birthweight. Even after controlling for gestational age at birth and other determinants of birthweight, for each microgram/dl increase in serum zinc early and later in pregnancy, birthweight increased by 5.8 and 8.6 g, respectively. Furthermore, after adjustment for initial zinc levels both the total change (beta = -7.0, P = 0.0007) and the rate of change (beta = -60.8, P = 0.007) in serum zinc during pregnancy were inversely associated with birthweight, i.e., the larger the fall in serum zinc during pregnancy, the smaller the infant. Low serum zinc level (less than 60 micrograms/dl) late in pregnancy was associated with greater than a five-fold increase in the odds (OR = 5.8, 95% CI = 1.8, 16.4) of giving birth to a low birthweight infant. The results of this study suggest a threshold for maternal serum zinc below which the prevalence of low birthweight increases rapidly.

A positive association between maternal serum zinc concentration and birth weight.

A study was conducted on a cohort of 476 women (364 black, 112 white), who attended the Jefferson County Health Department clinic for their prenatal care, to ascertain the relationship between maternal serum zinc concentration measured early in pregnancy and birth weight. For all subjects maternal serum zinc was significantly related to birth weight after various independent determinants of birth weight were controlled for. The data in this study indicate a threshold for maternal serum zinc concentration below which the prevalence of low birth weight increases significantly. Pregnant women who had serum zinc concentrations in the lowest quartile had significantly higher prevalence of low birth weight than did those mothers who had serum zinc concentrations in the upper three quartiles during pregnancy. These findings suggest that maternal serum zinc concentration measured early in pregnancy could be used to identify those women at higher risk of giving birth to a low-birth-weight infant.