Dietary pattern as a predictor of change in BMI z-score among girls

OBJECTIVES

To describe child and adolescent dietary patterns and to determine associations between childhood dietary pattern and longitudinal change in body mass index (BMI) z-score among girls.

POPULATION AND METHODS

Healthy girls (n = 101) aged 8-12 years at baseline and 11-19 years at follow-up participated in a longitudinal study of growth and development. Participants kept 7-day dietary records at two points in time. We incorporated time of day, frequency, and amount of energy consumed (defined as percentage of total energy consumed per dietary event) when characterizing dietary patterns.

RESULTS

Girls ate an average of 4-5 times per day and consumed most energy in the afternoon and in the evening/night, rather than in the morning. After controlling for baseline BMI, the mean percentage of daily energy consumed in the evening/night was positively associated with change in BMI z-score (P = 0.039). Eating between 4.0 and 5.9 times per day overall and no more than 1.9 times in the evening/night daily were negatively associated with change in BMI z-score (P = 0.002 and 0.047, respectively), after controlling for baseline BMI z-score.

DISCUSSION

Recommendations to decrease the percentage of energy coming from the evening/night meal and the number of dietary events to no more than six times per day and two times in the evening/night should be evaluated in future longitudinal investigations.

Food purchased away from home as a predictor of change in BMI z-score among girls

OBJECTIVES

To assess the relationship between eating food purchased away from home (FAH) and longitudinal change in body mass index (BMI) z-score among girls, and to assess the longitudinal tracking of eating FAH from childhood through adolescence.

DESIGN

Participants kept 7-day dietary records at two points in time. The records included the place and time for all foods consumed. We recorded how often participants ate FAH, calculated the percent of total energy derived from FAH, and classified foods as quick-service food, coffee-shop food, or restaurant food.

PARTICIPANTS

Healthy girls (n=101) between the ages of 8 and 12 y at baseline and 11 and 19 y at follow-up participated in a longitudinal study of growth and development at the Massachusetts Institute of Technology.

STATISTICAL ANALYSES

Analysis of variance was used to assess the relationship between change in BMI z-score and both the frequency of eating FAH and energy derived from eating FAH. The participants' baseline BMI z-score was a significant covariate and was controlled for in both models. We used the kappa coefficient to assess FAH tracking from childhood through adolescence.

RESULTS

The frequency of eating quick-service food at baseline was positively associated with change in BMI z-score (F=6.49, P<0.01). Participants who ate quick-service food twice a week or more at baseline had the greatest mean increase in BMI z-score compared to those who ate quick-service food once a week or not at all. Quick-service food eating tracked slightly from childhood through adolescence (k=0.17, P<0.05).

DISCUSSION

Adolescent girls who eat quick-service food twice a week or more are likely to increase their relative BMI over time.

Achieving a healthy lifestyle among United States adults: a long way to go

OBJECTIVE

The United States population has been advised to engage in various healthy lifestyle factors known to be associated with reduced morbidity and mortality from various chronic conditions. These include not smoking, adequate fruit and vegetable intake, adequate physical activity, and normal body weight. Little is known about the prevalence of United States adults who engage in all four of these behaviors, however.

DESIGN

Cross-sectional analysis.

SETTING

The third National Health and Nutrition Examination Survey (1988-1994).

PARTICIPANTS

16,176 participants aged > or = 21 years.

MAIN OUTCOME MEASURES

Percentage of participants engaging in four healthy lifestyle factors.

RESULTS

Overall, 6.8% of the US population engaged in all four healthy lifestyle factors. Women were more likely than men (P = .001), and Whites and participants of "other race or ethnicity" were more likely than African Americans and Mexican Americans to engage in all four healthy lifestyle factors. A significant positive educational gradient was also evident (P for linear trend <.001). The highest percentages of participants engaging in all four lifestyle factors occurred among men (15.8%) and women (18.4%) of "other" race who had at least 13 years of education. The lowest percentages were observed for White men (1.1%) and African-American women (0.9%) with little education.

CONCLUSIONS

The small proportion of US adults engaging in four healthy lifestyle factors demonstrates the enormity of the task that awaits the public health community in persuading Americans to adopt a multidimensional healthy lifestyle.

High serum retinyl esters are not associated with reduced bone mineral density in the Third National Health And Nutrition Examination Survey, 1988-1994

Hypervitaminosis A is sometimes associated with abnormalities of calcium metabolism and bone mineral status. A recent study found a negative association between reported dietary vitamin A intake and bone mineral density (BMD). Some segments of the U.S. population have high fasting serum retinyl ester concentrations, a physiological marker that may reflect high and possibly excessive vitamin A intake. We examined the association between fasting serum retinyl esters and BMD in the Third National Health and Nutrition Examination Survey, 1988-1994 (NHANES III), a large, nationally representative sample of the U.S. population. BMD was measured for the femoral neck, trochanter, intertrochanter, and total hip on all nonpregnant participants aged > or = 20 years; 5,790 participants also had complete data on fasting serum retinyl esters and covariates including age, body mass index (BMI), smoking, alcohol consumption, dietary supplement use, diabetes, physical activity, and, among women, parity, menopausal status, and the use of oral contraceptives or estrogen-replacement therapy. The sample included non-Hispanic white, non-Hispanic black, and Mexican American men and women. We examined the association between fasting serum retinyl esters and BMD at each site, controlling for covariates with multiple linear regression. We examined the association with osteopenia and osteoporosis with multiple logistic regression. Although the prevalences of high fasting serum retinyl esters concentration and low BMD were both substantial in this sample, there were no significant associations between fasting serum retinyl esters and any measure of bone mineral status.

Serum retinyl esters are not associated with biochemical markers of liver dysfunction in adult participants in the third National Health and Nutrition Examination Survey (NHANES III), 1988--1994

BACKGROUND

Serum retinyl ester concentrations are elevated in hypervitaminosis A. It was suggested that retinyl esters >10% of total serum vitamin A indicate potential hypervitaminosis, but this cutoff was derived from small clinical samples that may not be representative of the general population.

OBJECTIVE

We sought to examine the distribution of serum retinyl ester concentrations and associations between retinyl ester concentrations and biochemical markers of liver dysfunction in a nationally representative sample.

DESIGN

We assessed the associations between serum retinyl ester concentrations and 5 biochemical indexes of liver dysfunction by using multivariate linear and multiple logistic regression techniques and controlling for age, sex, use of supplements containing vitamin A, alcohol consumption, smoking status, and use of exogenous estrogens in 6547 adults aged > or =18 y in the third National Health and Nutrition Examination Survey (NHANES III), 1988--1994.

RESULTS

Thirty-seven percent of the sample had serum retinyl ester concentrations >10% of total serum vitamin A and 10% of the sample had serum retinyl esters >15% of total vitamin A. We found no associations between serum retinyl ester concentrations and 1) concentrations of any biochemical variable (multiple linear regression) or 2) risk of having biochemical variables above the reference range (multiple logistic regression). We did not find a serum retinyl ester value with statistically significant sensitivity and specificity for predicting increases in biochemical indexes of liver dysfunction.

CONCLUSIONS

The prevalence of serum retinyl ester concentrations >10% of the total vitamin A concentration in the NHANES III sample was substantially higher than expected but elevated retinyl ester concentrations were not associated with abnormal liver function.

Recommending calcium to reduce lead toxicity in children: a critical review

Assertions that adequate or supplemental calcium intake can reduce lead absorption in children are based on liberal extrapolation from animal studies, experiments with human adults, and cross-sectional studies of children that have a variety of methodologic weaknesses. Without stronger supporting evidence, statements that diet can ameliorate the deleterious effects of environmental lead could provide a false sense of efficacy and divert efforts from lead abatement and from behavioral modifications that might have more impact.

Serum retinol distributions in residents of the United States: third National Health and Nutrition Examination Survey, 1988-1994

BACKGROUND

Inadequate vitamin A status has been a potential nutritional problem for some segments of the US population, particularly children and the poor.

OBJECTIVE

We evaluated serum retinol concentration by using population-representative data from 16058 participants aged 4 to >/=90 y in the third National Health and Nutrition Examination Survey, 1988-1994.

DESIGN

We used multivariate regression to examine the simultaneous associations of sociodemographic, biologic, and behavioral factors with serum retinol concentration.

RESULTS

In children, serum retinol concentrations were greater with greater age, body mass index, serum lipids, and the use of supplements containing vitamin A. In adults, male sex, serum lipids, alcohol consumption, and age were positively associated with serum retinol concentration in most racial/ethnic strata. Household income was not associated with serum retinol concentration in children; associations were inconsistent in adults. The prevalence of serum retinol <0.70 micromol/L was very low in all strata; the prevalence of serum retinol <1.05 micromol/L was 16.7-33.9% in children aged 4-8 y and 3.6-14.2% in children aged 9-13 y, depending on sex and racial/ethnic group. The prevalence of serum retinol<1.05 micromol/L was higher in non-Hispanic black and Mexican American children than in non-Hispanic white children; these differences remained significant (P < 0.0001) after covariates were controlled for. Among adults, nonwhite women were significantly (P < 0.0001) more likely than white women to have serum retinol <1.05 micromol/L after covariates were controlled for.

CONCLUSIONS

Clinically low serum retinol concentration is uncommon in US residents aged > or = 4 y, although racial/ethnic and socioeconomic differences in serum retinol concentration still exist.

Beverage choices affect adequacy of children's nutrient intakes

OBJECTIVE

To assess the relationship between beverage choices and the adequacy of nutrient intakes among children and adolescents.

DESIGN

Beverages reported in 24-hour recall records were classified as milk, 100% juice, fruit-flavored drinks, or carbonated sodas. Recommended intakes were based on Recommended Dietary Allowances or Dietary Reference Intakes.

PARTICIPANTS

Four thousand seventy children aged 2 to 5, 6 to 11, and 12 to 17 years participating in the 1994-96 Continuing Survey of Food Intakes by Individuals.

STATISTICAL ANALYSIS

The likelihood of achieving recommended intakes of selected nutrients on the day of recall was assessed with multiple logistic regression including ounces of milk, juice, fruit-flavored drinks, and carbonated sodas in the model while controlling for sex, age in years, race/ethnic group, household income, and total energy intake.

RESULTS

Milk consumption was positively (P<.0001) associated with the likelihood of achieving recommended vitamin A, folate, vitamin B(12), calcium, and magnesium intakes in all age strata. Juice consumption was positively (P< or =. 001) associated with achieving recommended vitamin C and folate intakes in all age strata and magnesium intakes among children aged 6 years and older. Carbonated soda consumption was negatively (P< or =. 01) associated with achieving vitamin A intake in all age strata, calcium in children younger than 12 years, and magnesium in children aged 6 years and older.

CONCLUSION

Beverage choice can have a significant effect on the nutrient adequacy of the diets of children and adolescents.

Nutrient intakes and dietary patterns of young children by dietary fat intakes

OBJECTIVE

To determine whether low fat intake is associated with increased risk of nutritional inadequacy in children 2 to 8 years old and to identify eating patterns associated with differences in fat intake.

STUDY DESIGN

Using 2 days of recall from the Continuing Survey of Food Intake by Individuals (CSFII), 1994 to 1996, we classified 2802 children into quartiles of energy intake from fat (<29%, 29% to 31.9% [defined as moderate fat], 32% to 34.9%, and > or =35%) and compared nutrient intakes, the proportion of children at risk for inadequate intakes, Food Pyramid servings, and fat content per serving across quartiles.

RESULTS

More children in quartile 2 were at risk for inadequate intakes of vitamin E, calcium, and zinc than children in higher quartiles (P <.0001); more children in quartiles 3 and 4 were at risk for inadequate intakes of vitamins A and C and folate (P <.001). Fruit intake decreased across quartiles (P <.0001); whereas vegetable, meat, and fat-based condiment intakes increased (P <.0001). Fat per serving of grain, vegetables, dairy, and meat increased across quartiles (P <.0001).

CONCLUSIONS

Moderate-fat diets were not consistently associated with an increased proportion of children at risk for nutritional inadequacy, and higher-fat diets were not consistently protective against inadequacy. Dietary fat could be reduced by judicious selection of lower-fat foods without compromising nutritional adequacy.

Blood lead concentration and children's anthropometric dimensions in the Third National Health and Nutrition Examination Survey (NHANES III), 1988-1994

OBJECTIVE

To assess the association between lead exposure and children's physical growth.

DESIGN

Cross-sectional analysis of data from the Third National Health and Nutrition Examination Survey, 1988-1994.

PARTICIPANTS

A total of 4391 non-Hispanic white, non-Hispanic black, and Mexican-American children age 1 to 7 years.

MEASUREMENTS AND RESULTS

We investigated the association between blood lead concentration and stature, head circumference, weight, and body mass index with multiple regression analysis adjusting for sex, ethnic group, iron status, dietary intake, medical history, sociodemographic factors, and household characteristics. Blood lead concentration was significantly negatively associated with stature and head circumference. Regression models predicted reductions of 1. 57 cm in stature and 0.52 cm in head circumference for each 0.48 micromol/L (10 micrograms/dL) increase in blood lead concentration. We did not find significant associations between blood lead concentration and weight or body mass index.

CONCLUSIONS

The significant negative associations between blood lead concentration and stature and head circumference among children age 1 through 7 years, similar in magnitude to those reported for the Second National Health and Nutrition Examination Survey, 1976-1980, suggest that although mean blood lead concentrations of children have been declining in the United States for 2 decades, lead exposure may continue to affect the growth of some children.

Dietary folate intake in US adults: findings from the third National Health and Nutrition Examination Survey

To estimate the dietary intake of folate in the US population, we used data from the first phase of the third National Health and Nutrition Examination Survey (NHANES III) conducted from 1988 through 1991. Using data from a single 24-hour dietary recall, the mean intake for the population aged 17 years and older was 283.4 microg/day (standard error [SE] 3.8). After correcting for a single 24-hour dietary recall, 70.0% (SE 1.1%) met the current recommended dietary allowance (RDA) for folate. Because data on intake of nutritional supplements were not available, it is likely that a higher proportion of the United States population met the RDA for folate. Folate intake was not uniform in the population: men had higher intakes than women, and African Americans had lower intakes than persons of other races. African-American men had lower absolute folate intakes than white men (P=0.001) or Mexican-American men (P=0.002). African-American women had the lowest folate intakes among women (P<0.001 for white women, P=0.006 for Mexican-American women, and P=0.003 for other women). When folate intakes were expressed as mg per 1,000 calories, the results were very similar. Because of methodologic differences in administering the 24-hour dietary recalls in NHANES II and NHANES III, it is unclear whether increases in dietary folate consumption have occurred since NHANES II, which was conducted during 1976-80, and the Continuing Survey of Food Intake by Individuals, which was conducted during 1985-86. The low dietary consumption of folate by African Americans, if confirmed, suggests the need for public health strategies to increase consumption of folate among this group.

Risk factors for coronary heart disease among Navajo Indians: findings from the Navajo Health and Nutrition Survey

Coronary heart disease was uncommon among the Navajo in the past, but appears to have increased substantially over the last few decades. The 1991-1992 Navajo Health and Nutrition Survey, which included interviews and examinations of 303 men and 485 women between the ages of 20 and 91 y, is the first population-based examination of coronary heart disease risk factors in this tribe. Coronary heart disease risk characteristics were common, particularly overweight (men, 35%; women, 62%), hypertension (men, 23%; women, 14%) and diabetes mellitus (men, 17%; women, 25%). Among 20- to 39-y-olds, a large proportion of men reported that they currently smoked cigarettes (23%); use of chewing tobacco or snuff was also prevalent among these 20- to 39-y-old men (37%) and women (31%). Although serum concentrations of total cholesterol were fairly comparable to those seen in the general U.S. population, fasting serum triglyceride concentrations were high (median: men, 132 mg/dL; women, 137 mg/dL), and concentrations of HDL cholesterol were low, particularly among women (median: men, 42 mg/dL; women, 44 mg/dL). Body mass index was associated with levels of most risk factors, and, independently of the level of overweight, a truncal pattern of body fat was related to adverse lipid levels among men. A large proportion of men (20%) and women (30%) reported not having participated in physical activity during the preceding month. Lessons learned from past intervention activities among the Navajo, particularly those for diabetes, may be useful in managing these risk factors to reduce the future burden of coronary heart disease.

Intake of nutrients and food sources of nutrients among the Navajo: findings from the Navajo Health and Nutrition Survey

Diet has been implicated in the etiology of chronic diseases in many populations, including the Navajo and other American Indian tribes. This report describes the current nutrient intake of the Navajo and identifies the primary food sources of key nutrients. In the Navajo Health and Nutrition Survey, interviewers obtained single 24-h diet recalls from 946 nonpregnant participants age 12-91 between October 1991 and December 1992. Among various sex and age groups, total fat contributed 33-35% of energy and saturated fat contributed 10-11% of energy in the diets. Median fiber intake was 11-14 g/d. Median intakes of vitamin A, vitamin E, vitamin B-6, folate, calcium and magnesium were below sex- and age-specific recommended dietary allowances (RDA) for men and women of all age groups. Intake of vitamin C was below the RDA for men and women age 20 and older. Median iron intake was below the RDA for women under age 60. Fruits and vegetables were each consumed less than once per day per person, as were dairy products. Fry bread and Navajo tortillas, home-fried potatoes, mutton, bacon and sausage, soft drinks, coffee and tea provided 41% of the energy and 15-46% of the macronutrients consumed. Recommendations to increase the intake of essential micronutrients in the Navajo diet are presented.

Obesity, levels of lipids and glucose, and smoking among Navajo adolescents

Although there is a high prevalence of overweight among Navajo children and adolescents, other risk factors for chronic disease in this population have received little attention. We therefore examined the distribution and interrelationships of overweight, cigarette smoking, blood pressure and plasma levels of lipids and glucose among 160 Navajo 12- to 19-y-olds. In agreement with previous reports, participants were approximately 2 kg/m2 heavier than adolescents in the general U.S. population, and the prevalence of overweight (> 85th percentile) was 35-40%. Levels of total cholesterol and blood pressure were similar to those in the general U.S. population, but Navajo adolescents had a 5-10 mg/dL lower median level of HDL cholesterol, and a 30 mg/dL higher median triglyceride level. Eight percent of the adolescents examined had either impaired glucose tolerance or diabetes mellitus as assessed through an oral glucose tolerance test (n = 10) or self-report (n = 1). Relative weight (kg/m2) was associated with adverse levels of lipids, lipoproteins and glucose, with overweight adolescents having a fivefold greater risk for elevated triglyceride levels than other adolescents. Tobacco use was fairly prevalent among boys (24% cigarettes, 23% smokeless tobacco), but not girls (9% cigarettes, 3% smokeless tobacco). Because of its associations with other risk factors and with various chronic diseases in later life, it may be beneficial to focus on the primary prevention of obesity among Navajo children and adolescents.

Diabetes mellitus among Navajo Indians: findings from the Navajo Health and Nutrition Survey

Noninsulin-dependent diabetes mellitus is a major health problem among most American Indian tribes. This is the first population-based reservation-wide study of the Navajo that has used oral glucose tolerance testing to determine diabetes status. Employing WHO criteria, we found an age-standardized prevalence of diabetes mellitus (DM) of 22.9% among persons aged 20 y and older. This prevalence is 40% higher than any previous age-standardized estimate for the Navajo and four times higher than the age-standardized U.S. estimate. More than 40% of Navajo aged 45 y and older had DM. About one third of those with DM were unaware of it, with men more likely to be unaware than women. Among persons with a medical history of DM, almost 40% had fasting plasma glucose values > or = 200 mg/dL. Persons with DM were heavier, more sedentary and more likely to have a family history of DM than were persons without DM. Persons with DM had more hypertension, lower HDL levels and higher triglyceride levels than their counterparts without DM. Insulin usage was infrequent among persons with a history of DM, and about one third of women with such a history used no medical therapy to control their diabetes. Although important measures to combat diabetes have already been undertaken by the Navajo, additional efforts are required to slow the progression of this disease and prevent its sequelae.

The health of Navajo women: findings from the Navajo Health and Nutrition Survey, 1991-1992

Cancer-screening behaviors, reproductive history, risk behaviors during pregnancy and chronic disease risk factors were examined in a representative sample of 566 Navajo women residing on the Navajo Reservation in 1991-1992. Among all women 15 y and older, 59% were overweight, 4% were current smokers, 10% currently used smokeless tobacco and 12% were anemic. Seventy-one percent of Navajo women aged 18 and older reported ever having had a Pap smear, but only 35% of women aged 50 and over reported ever having had a mammogram. Among parous women, the prevalence of having received no prenatal care for any pregnancy declined from 60% among women 60 and older to 13% among women 20-29 y of age, and the prevalence of ever having had a child born at home declined from 82 to 2%. These data suggest marked secular improvement in these pregnancy-related risk behaviors. However, data on cancer-screening behaviors indicate opportunities to improve health of Navajo women by increasing their use of mammography and Pap smear screening services.

Rationale, design and methodology for the Navajo Health and Nutrition Survey

As recently as 1990, there was no reservation-wide, population-based health status information about Navajo Indians. To remedy this shortcoming, the Navajo Health and Nutrition Survey was conducted from 1991 to 1992 to assess the health and nutritional status of Navajo Reservation residents using a population-based sample. Using a three-stage design, a representative sample of reservation households was selected for inclusion. All members of selected households 12 y of age and older were invited to participate. A total of 985 people in 459 households participated in the study. Survey protocols were modeled on those of previous national surveys and included a standard blood chemistry profile, complete blood count, oral glucose tolerance test, blood pressure, anthropometric measurements, a single 24-h dietary recall and a questionnaire on health behaviors. The findings from this survey, reported in the accompanying papers, inform efforts to prevent and control chronic disease among the Navajo. Lessons learned from this survey may be of interest to those conducting similar surveys in other American Indian and Alaska Native populations.

Weight, body image, and weight control practices of Navajo Indians: findings from the Navajo Health and Nutrition Survey

Historically, the Navajo exhibited a low prevalence of overweight, but a number of small studies over the past few decades indicate that the prevalence is increasing. In the population-based Navajo Health and Nutrition Survey conducted in 1991-92, overweight was defined as a body mass index (BMI, kg/m2) at or above the 85th percentile (BMI > 27.8 for men, > 27.3 for women) of the Second National Health and Nutrition Examination Survey. One third of men age 20 and 39 and one half of men age 40 and 59, but fewer than 10% of men age 60 and older were overweight. Two thirds or more of women in all age groups were overweight. Nineteen percent of the participants underestimated their weight status (underweight, appropriate, overweight) relative to their BMI category and 17% overestimated their weight status. Women overestimated their weight status more often than men (P < 0.05), and participants age 20-39 overestimated their weight status more often than older participants (P < 0.001). Men and women age 60 and older preferred heavier body shape models as ideals of health more often than younger participants (P < 0.001). Nearly half of the participants, regardless of their weight status, reported that they were trying to lose weight; most reported using diet and exercise. Because overweight is an important risk factor for many chronic diseases, including diabetes mellitus, cardiovascular disease and cancer, primary prevention of overweight and weight management for adults are recommended to prevent an increase in the burden of chronic disease among the Navajo.

Prevalence of hypertension among Navajo Indians: findings from the Navajo Health and Nutrition Survey

Hypertension and other chronic diseases are becoming increasingly important health problems for many Native American people, including the Navajo. A community-based survey that included three standardized measurements of blood pressures, was conducted during 1991-92 on the Navajo Reservation. Among the 780 adults examined, the overall age-standardized prevalence of hypertension, defined as an elevated systolic (> or = 140 mm Hg) or diastolic (> or = 90 mm Hg) blood pressure, or possession of prescription antihypertensive medications, was 19% (24% among men and 15% among women). The prevalence of hypertension increased with age and relative weight, and among men, was associated with diabetes mellitus. Among women, hypertension was associated with a central distribution of body fat, cigarette smoking, self-reported diabetes mellitus and impaired glucose tolerance. Although only 50% of the persons found to have elevated blood pressure at the examination reported they had been previously told that they had hypertension, persons who had been previously diagnosed with hypertension had a slightly higher rate (approximately 60%) of blood pressure control than that seen in the general U.S. population. On the basis of these results, the prevalence of hypertension among the Navajo appears to have substantially increased since the 1930s. Improved prevention and management of hypertension, especially for overweight and diabetic individuals, may reduce morbidity and mortality from cardiovascular and renal disease.

Intake of nutrients related to cardiovascular disease risk among three groups of American Indians: the Strong Heart Dietary Study

BACKGROUND

Although diet is implicated in the elevated rate of cardiovascular disease among some American Indian tribes, the dietary intakes of these individuals have not been described. The Strong Heart Dietary Study compared diets of 10 tribes in Arizona, Oklahoma, and the Dakotas to examine the possible contribution of diet to cardiovascular and other chronic diseases.

METHODS

During 1988-1991, 892 people responded to a 24 hr diet recall questionnaire. Nutrient intake by study area, sex, and age group were compared by analysis of variance, and intakes were compared with nutrient intakes reported by participants in Phase 1 of the Third National Health and Nutrition Examination Survey and with dietary recommendations of the National Research Council, the American Heart Association, and the Healthy People 2000 objectives.

RESULTS

The intake of energy and nutrients varied significantly by sex and age. Men consumed more energy, macronutrients, and sodium than did women (P < or = 0.001). Women's diets were denser in carbohydrate, beta-carotene, vitamin C, and vitamin E than were men's diets (P < or = 0.001). Younger participants consumed more energy, macronutrients, vitamin E, and sodium than did older participants (P < or = 0.001). Older participants had diets denser in protein and beta-carotene than did younger participants (P < or = 0.001). Energy intake did not differ significantly by study area, but men in Arizona consumed more energy from carbohydrate and less energy from total fat than did men elsewhere (P < or = 0.01). Men and women in Arizona consumed more cholesterol and fiber than did other participants (P < or = 0.01) and less of the antioxidant vitamins (P < or = 0.01). Participants in the Strong Heart Diet Study reported diets higher in fats and cholesterol than did participants in Phase 1 of the Third National Health and Nutrition Examination Survey. Few Strong Heart participants achieved dietary recommendations for the reduction of risk of chronic disease.

CONCLUSIONS

Area differences in nutrient intake were observed, but most participants consumed diets associated with increased risk of heart disease and other chronic diseases. Women and older participants in general reported healthier nutrient intakes. Dietary intervention programs should educate American Indians about dietary modifications to reduce the risk of cardiovascular and other nutrition-related disorders.

Dietary surveillance for states and communities

Information about dietary behaviors, attitudes, and knowledge is important for state and local health agencies because national monitoring lacks the local representativeness and timeliness necessary to catalyze community interest and to design, target, and evaluate dietary intervention programs. Currently, however, both methods and resources are limited for surveying diet in the population of a state or community. Brief assessments are included in the Youth Risk Behavior Surveillance System for adolescents, which is conducted by state departments of education, and in the Behavioral Risk Factor Surveillance System for adults, which is operated by state departments of health. More quantitatively precise measurements are being made by a few states and communities but personnel and financial resources for such surveys are limited. Nutritionists in state and local health agencies should explore the possibility of developing public-private partnerships with food producers, retailers, and marketers to collect information about dietary determinants and behaviors in states and communities. Better standardization of dietary assessment methods is needed, as is development of better methods to identify attitudes about diet and barriers to dietary improvement. Most important, though, dietary surveillance in states and communities must be more strongly tied to intervention programs intended to improve nutrition in those populations.

Efficacy and safety of excimer laser photorefractive keratectomy and radial keratotomy for bilateral myopia

PURPOSE

To compare the safety and efficacy of radial keratotomy (RK) and photorefractive keratectomy (PRK) to correct myopia.

METHODS

In this randomized, prospective, parallel-group study, 33 patients with bilateral myopia of 1.00 to 5.00 diopters (D) had PRK in one eye and RK in the other. The order of surgeries and treatment assignments were randomized, and the bilateral surgeries were within 1 week for each patient. Data were collected using standardized procedures. Clinical measurements and satisfaction surveys were taken in masked fashion.

RESULTS

Eyes that had PRK had statistically significantly more residual myopia than RK-treated eyes at 3, 6, and 12 months postoperatively. This result was attributed to the use of an older excimer laser PRK algorithm that was used at the initiation of the study. No eye that had PRK was overcorrected by 0.50 D or more at 1 year postoperatively, while seven eyes that had RK were overcorrected by at least 0.50 D and six were overcorrected by 1.00 D. Eyes that had PRK had a statistically significant mean shift in the myopic direction between 6 and 12 months postoperatively; two RK eyes had hyperopic shifts of 1.00 D. Three RK eyes and two PRK eyes failed to achieve an uncorrected visual acuity of 20/40 or better by 12 months postoperatively. No eye lost any best corrected visual acuity.

CONCLUSION

The two procedures were comparably safe and effective in treating mild to moderate myopia under this protocol. Eyes that had PRK were somewhat more myopic at 1 year after surgery, attributable to the older PRK ablation algorithm. Adoption of newer (current) laser algorithms has improved the predictability of PRK. There was also evidence of reduced variability of outcome in the PRK group. The PRK eyes did not exhibit hyperopic shifts during the 1 year follow-up.

High-risk nutrient intakes among low-income Mexican women in Chicago, Illinois

OBJECTIVES

The Cross-sectional Cooking, Eating, Nutrition, and Shopping (CENAS) Survey was used to obtain data on food consumption patterns of low-income Mexicans living in Chicago, Ill.

DESIGN

As part of the CENAS Survey, 186 Mexican women provided 24-hour dietary recall data.

OUTCOME MEASURES

Distributions of macronutrient and micronutrient intakes were determined. The proportions of CENAS Survey participants achieving the National Heart Association and National Cancer Institute dietary guidelines were calculated. Intakes of Mexican women in Chicago were compared with intakes of Mexican women of similar socioeconomic status in Texas, Mexican-American women participating in phase 1 of the third National Health and Nutrition Examination Survey (1988-1991), and Mexican-American women participating in the Hispanic Health and Nutrition Examination Survey (1982-1984).

STATISTICAL ANALYSIS

Tests were used to compare the nutrient intakes of CENAS Survey respondents with published results from other studies.

RESULTS

The proportion of respondents reporting intakes less than two thirds of Recommended Dietary Allowances for nine micronutrients ranged from 11% (thiamin and riboflavin) to 82% (folacin). Respondents also reported median fat (34% of energy) and fiber (16.9 g/day) intakes that departed from recommendations to reduce the risk of heart disease and cancer. APPLICATIONS AND CONCLUSIONS: Half or more of the Mexican women interviewed in Chicago reported inadequate consumption of calcium, folate, zinc, and iron; higher than recommended intakes of fats; and lower than recommended intakes of fiber, indicating the need for nutrition education and intervention. Their nutrient consumptions differed significantly from those of Mexican-American women in the United States, suggesting possible regional or temporal variation in dietary patterns and underscoring the need for population-specific interventions.

Relation of body fat distribution to ischemic heart disease. The National Health and Nutrition Examination Survey I (NHANES I) Epidemiologic Follow-up Study

Although an excess of adipose tissue in the abdominal and truncal regions is associated with various metabolic alterations, relatively few cohort studies have examined its importance in the development of ischemic heart disease, and little information is available from black populations. The authors examined the relation of central obesity, as characterized by a thick subscapular skinfold relative to the triceps skinfold, to the incidence of ischemic heart disease among 9,822 persons in the Epidemiologic Follow-up Study of the National Health and Nutrition Examination Survey I; baseline data were collected in 1971-1975 and follow-up was through 1987. We found that, independently of relative weight, cigarette smoking, and other covariates, the hazard rate ratios for ischemic heart disease incidence contrasting the upper and lower quintiles of central obesity were 1.75 (95% confidence interval 1.3-2.3) among women and 1.65 (95% confidence interval 1.3-2.2) among men. Although central obesity was related similarly to disease among white and black men, the association among women differed between whites (rate ratio = 1.94) and blacks (rate ratio = 0.73); p = 0.002 for race x the central obesity product term. Additional research is needed to clarify the relation of various anthropometric measurements to ischemic heart disease, particularly among blacks, but the assessment of fat distribution may help identify high-risk persons for whom weight loss might be most beneficial.

Clear lens extraction and intraocular lens implantation in a patient with bilateral anterior lenticonus secondary to Alport's syndrome

We describe bilateral phacoemulsification and implantation of foldable silicone intraocular lenses in a 25-year-old woman with Alport's syndrome and severe anterior lenticonus. Contrary to previous reports of lens capsule fragility in Alport's syndrome, this patient had relatively tough capsules, as do most patients her age. Apart from the tough capsules and positive pressure, which required the use of a viscoelastic to maintain the anterior chamber, the surgeries were unremarkable. The patient achieved excellent visual and refractive results.

Small incision surgery with the STAAR Elastimide three-piece posterior chamber intraocular lens

One hundred twelve patients scheduled for uncomplicated cataract removal were randomly assigned to receive a STAAR Elastimide three-piece foldable intraocular lens inserted through a 4.0 mm incision or a STAAR poly(methyl methacrylate) (PMMA) lens inserted through a 7.0 mm incision. The same surgeon performed all surgeries using identical techniques, except for incision size and number of sutures. Patients receiving Elastimide lenses had significantly better uncorrected visual acuity postoperatively than patients receiving PMMA lenses and also had significantly less keratometric cylinder, surgically induced cylinder (vector method), and refractive cylinder. The Elastimide foldable lens offers the advantages of small incision surgery for patients who require a three-piece lens.

Visual disturbances associated with oval-optic poly(methyl methacrylate) and round-optic silicone intraocular lenses

A prospective, randomized, double-masked clinical trial of 182 patients compared the frequency of visual disturbances associated with two small incision intraocular lenses (IOLs): the Alcon MZ20BD 5 mm x 6 mm oval-optic poly(methyl methacrylate) (PMMA) IOL and the STAAR AQ1016 round-optic silicone IOL. The samples were similar at baseline. There were no significant differences in visual acuity, mean keratometric cylinder, or surgically induced cylinder between the two groups postoperatively. Patients completed a satisfaction questionnaire and visual symptom inventory of ten items three months postoperatively. Those with the oval-optic PMMA IOL reported significantly more visual symptoms than those with the round-optic silicone IOL (P = .03). The oval-optic group reported three symptoms more frequently: reflections, halos or rings around lights, and objects at arm's length appearing blurry (P < or = .010). The status of the fellow eye (cataract or pseudophakic) did not differ by randomization group, and the distribution of visual symptoms did not differ by status of the fellow eye. Frequency and severity of visual complaints were modest overall; only 1% in each group was unsatisfied with the visual results.

Photorefractive keratectomy following penetrating keratoplasty

We present 3 eyes that underwent photorefractive keratectomy (PRK) for residual myopia after penetrating keratoplasty, and 1 eye that was treated for recurrent granular dystrophy and myopia following penetrating keratoplasty. The 3 refractive eyes experienced improvements in visual acuity and refractive error through 3 months postoperative, but exhibited regression of effect after 6 months postoperative. One eye also exhibited substantial corneal haze at three months postoperative that was not responsive to steroid retreatment. The eye with granular dystrophy obtained symptomatic relief as well as improvement in vision. We tentatively conclude that the corneal transplant reacts to photorefractive keratectomy in much the same way as a normal cornea. Eyes with substantial degrees of post-graft myopia exhibit regression of refractive effect, much like high myopes following primary photorefractive keratectomy. Photorefractive was unable to prevent the recurrence of granular dystrophy in the transplanted tissue. The eyes reported here achieved only modest long-term visual and refractive improvements.

High prevalence of cleft lip among the Bari Indians of western Venezuela

Cleft lip with or without cleft palate (CL +/- P) is of high prevalence in an isolated, inbred indigenous population of the Venezuelan rain forest: 12 contemporary probands are known in a population of 1200. CL +/- P is familial in this population. One kindred contains four affected siblings and a total of eight probands. The mode of transmission of CL +/- P is under investigation through the collection and biological verification of genealogies and through screening for selected sequence-based polymorphisms. Polymerase chain reaction (PCR) assays were successfully applied to recover DNA from blood dried onto filter paper in the field. Eleven samples from probands and their first-degree relatives have been analyzed for DNA sequence-based polymorphisms for TGF-A and HOX7. No significant linkages for either locus were found. Evaluation of the distribution of probands in four genealogies indicates that CL +/- P could be transmitted as an autosomal recessive trait in this population. We believe this is the first report of this mode of transmission for nonsyndromic CL +/- P.

Effect of incision size on early postoperative visual rehabilitation after cataract surgery and intraocular lens implantation

One hundred fifty-one unilateral cataract patients were randomly assigned to receive either a one-piece Staar AA-4203 silicone intraocular lens inserted through a 3.5 mm incision, an loptex 5 mm x 6 mm oval optic lens inserted through a 5.5 mm incision, or an AMO three-piece modified C-loop 6.0 round optic poly(methyl methacrylate) lens inserted through a 6.5 mm incision. Follow-up was 97% at two days postoperatively and 84% at one week and two months postoperatively. At one week postoperatively, 62% of 3.5 mm incision cases had uncorrected visual acuity of 20/40 or better compared with 33% of 5.5 mm (P < .01) and 43% of 6.5 mm incision cases. At two months postoperatively, 85% of 3.5 mm incision cases had uncorrected visual acuity of 20/40 or better compared with 64% of 6.5 mm (P < .05) and 71% of 5.5 mm incision cases. The 3.5 mm incision cases had significantly less total keratometric cylinder than other cases at all postoperative examinations (P < or = .001) and less surgically induced cylinder at two days and one week post-operatively (P < or = .02). The 5.5 mm and 6.5 mm incision cases did not differ significantly in visual acuity or astigmatism at any examination.

Excimer laser photoablation of primary familial amyloidosis of the cornea

A 31-year old female underwent lamellar keratoplasty for the treatment of bilateral primary familial amyloidosis of the cornea in 1983 (OS), 1986 (OD), and 1989 (OS). The lesions recurred bilaterally and visual acuity in 1992 was 20/400 in each eye. After debridement of essentially all corneal epithelium, the entire cornea of the left eye was treated with excimer laser phototherapeutic keratectomy (PTK). One month postoperatively, visual acuity was 20/50 and the corneal surface appeared smooth and clear with no evidence of recurrence. Four months postoperatively, the patient continued to be free of recurrence.

Effect of cataract wound incision size on acute changes in corneal topography

A randomized prospective trial compared keratometric and visual outcomes for 196 patients receiving 3.2 mm, 5.0 mm, or 6.0 mm incisions for cataract removal and intraocular lens implantation. There were no statistically significant differences among the groups preoperatively or at one to two days or three to six months postoperatively in mean keratometric cylinder, no differences postoperatively in surgically induced cylinder, and no differences in best-corrected visual acuity. Significantly more (P < .01) 3.2 mm cases (75%) had uncorrected visual acuity of 20/40 or better at one to two days postoperatively than 5.0 mm (50%) or 6.0 mm cases (47%). Computer-assisted corneal topographic images were available for the last 56 patients enrolled. Patients receiving 3.2 mm incisions had significantly less wound-related flattening than other patients (P < .05) and tended to have fewer surgically induced changes in corneal shape overall. Changes identified by corneal topography were inconsistent with keratometrically assessed cylinder in 14 patients.

Effects on serum lipids of adding instant oats to usual American diets

This study was designed as a test of the serum lipid response and dietary adaptation to recommended daily inclusion of instant oats in an otherwise regular diet. Hypercholesterolemic adults were randomly assigned to a control or intervention group. Participants in the intervention group were given packages of instant oats and requested to eat two servings per day (approximately two ounces dry weight), substituting the oats for other carbohydrate foods in order to maintain baseline calorie intake and keep weight stable. Serum lipids were measured in blood collected by venipuncture at baseline, four weeks, and eight weeks. Baseline mean total cholesterol (TC) levels were 6.56 mmol/L and 6.39 mmol/L for intervention and control groups, respectively. After eight weeks, mean serum total cholesterol of the intervention group was lower by -0.40 mmol/L, and mean net difference in TC between the two groups was 0.32 mmol/L (95% CI: 0.09, 0.54). Low-density lipoprotein-cholesterol was similarly reduced with mean net difference of 0.25 mmol/L (95% CI: 0.02, 0.48) between the two groups. Mean soluble fiber intake increased along with slight self-imposed reductions in mean total fat, saturated fat, and dietary cholesterol intake in the intervention group. Neither group changed mean body weight. Daily inclusion of two ounces of oats appeared to facilitate reduction of serum total cholesterol and LDL-C in these hyperlipidemic individuals.

Diet, body size, and plasma lipids-lipoproteins in young adults: differences by race and sex. The Coronary Artery Risk Development in Young Adults (CARDIA) study

The Coronary Artery Risk Development in Young Adults (CARDIA) study completed baseline dietary assessment, measurement of body mass index, and lipid and lipoprotein analyses on 5,111 participants. CARDIA includes black and white men and women between 18 and 30 years of age at baseline (1985-1986), recruited in Birmingham, Alabama, Chicago, Illinois, Minneapolis, Minnesota, and Oakland, California. Diet was assessed by a detailed interviewer-administered diet history that measured the usual eating pattern over the past month. Possible sex, race, age, and educational differences in diet, body size, and lipids-lipoproteins were explored. Nutrient analyses indicate that the Keys score, a measure of dietary fat composition, is significantly correlated with plasma cholesterol in older (aged 25-30 years) white men (r = 0.12, p less than 0.01) and older white women (r = 0.12, p less than 0.001). In multiple linear regression analyses, body mass index was positively and significantly associated with total cholesterol and low density lipoprotein cholesterol and inversely associated with high density lipoprotein cholesterol across all race-sex groups. The Keys score was significantly associated with total cholesterol and low density lipoprotein cholesterol in white men and women. Education was associated with high density lipoprotein cholesterol in black and white women and white men. In these young adults, dietary fat intake and body mass index were related to blood lipids in certain subgroups. In black and white men and black women, blood cholesterol increased with age across race-sex groups independently of these covariates. In view of the many factors affecting plasma cholesterol and the limitations of the dietary history method, these cross-sectional data are useful in characterizing diet and lipid differences. There appears to be general disparity between recommended dietary intake of total fat, saturated fat, and other nutrients and actual dietary intake in young adults, regardless of age and educational level.

Comparison of three weight-for-height indices in blood pressure studies in children

Associations between blood pressures and three indices commonly used to assess relative obesity (weight (kg)/height (m)2, weight (kg)/height (m)3, and weight (kg)/height (m)p) were examined in a multiracial sample of children attending private schools in Chicago, Illinois. The 1,723 boys and 1,878 girls were 5-10 years old at the time of the survey (1975-1978). Inclusion of white, black, Hispanic, and Asian children permitted comparison of the relation between anthropometric variables and blood pressures across racial groups. The three weight-for-height indices used as estimates of relative obesity yielded nearly identical regression models, suggesting that, in spite of ongoing debate about the most appropriate index for describing relative obesity in children, it makes little difference which index is used.

Dietary assessment in children using electronic methods: telephones and tape recorders

Selection of dietary assessment methodology is important in dietary intervention studies. Few studies have reported the relative merits of various assessment methods or the feasibility of electronic methods in pediatric populations. Parent-child dyads performed telephone recalls (no. = 32) and tape recorded dietary records (no. = 33). Traditional recalls were first conducted to familiarize parents and children with the telephone recall procedure, to introduce two-dimensional food models, and to instruct on the use of the tape recorder. Parents monitored and documented as unobtrusively as possible the child's intake on the day before the telephone recall and also on the day of the taped record. Children were called at random to reduce bias. Simple correlation coefficients (r) were calculated for nine nutrients and calories for both methods. For telephone recalls, values ranged from a low of r = .64 for saturated and polyunsaturated fat to r = .85 for cholesterol and r = .93 for iron. Tape-recorded data yielded r = .80 or above, except calories with r = .68 (p less than .001 for all values, 1-tail tests). Mean nutrient values were within expected ranges, e.g., 1,800 kcal +/- 500, with saturated fat about 14% of calories per day. Comparisons between parents and childrens reports of food frequencies and portion sizes revealed the best correlations for beverages, bread-cereals-crackers, meat-fish-poultry, and mixed dishes. We conclude that preadolescent children are able to provide dietary intake data using electronic methods in a manner that compares favorably with their parents' written records.

The utility of indirect measures of obesity in racial comparisons of blood pressure. CARDIA Study Group

The associations between estimates of obesity derived from anthropometric measurements (body mass index, the sum of three skin folds, and the computed percent body fat) and blood pressures were examined by multiple regression analysis in 4508 young black and white adults. The three estimates of obesity yielded similar results in regression analyses. The strength of associations between these three estimates of obesity and systolic and diastolic blood pressures did not differ in black and white subjects of either sex. All three estimates lead to the same interpretation of the relationship between obesity and systolic or diastolic blood pressure. Estimated percent body fat offered no advantage over the other indices in this context.

Relation of body fatness and its distribution to cardiovascular risk factors in young blacks and whites. The role of insulin

Persons whose body fat is distributed predominantly in the abdomen compared with the hips are at increased risk of several chronic diseases. This study examined the cross-sectional relation of percent body fat, computed from skinfold thickness, and fat distribution, measured by the waist-to-hip girth ratio, to physiologic cardiovascular risk factors in a biracial sample (blacks and whites) of young adults aged 18-30 years. The subjects were persons who were examined at baseline (1984-1986) in the Coronary Artery Risk Development in Young Adults Study in four US metropolitan areas. The two hypotheses tested were that 1) after adjusting for percent body fat, waist-to-hip girth ratio is associated with several physiologic risk factors, and 2) fasting concentrations of serum insulin partly explain such association. Percent body fat was significantly associated with all measured blood lipids, lipoproteins, apolipoproteins, uric acid, and blood pressure. Waist-to-hip girth ratio was significantly, although more weakly, associated in multivariate models with blood concentrations of triglycerides, high density lipoprotein (HDL) cholesterol, HDL2 cholesterol, apolipoproteins A-I and B, low density lipoprotein cholesterol (in women only), uric acid, and systolic blood pressure, but was not associated in either sex with total cholesterol, HDL3 cholesterol, or diastolic blood pressure. Fasting serum insulin concentrations were significantly associated with percent body fat (Pearson r = 0.45-0.53), waist-to-hip girth ratio (Pearson r = 0.18-0.27), and most of the physiologic risk factors. Inclusion of fasting insulin in multivariate models reduced, but rarely eliminated, associations between waist-to-hip girth ratio and the physiologic risk factors. These findings suggest that obese young adults, especially those with abdominal fat preponderance, carry a physiologic profile that places them at higher risk of cardiovascular disease, and that fasting insulin concentrations are only partly explanatory.

Ethnic differences in blood pressure, pulse rate, and related characteristics in young adults. The CARDIA study

This study examined ethnic differences in blood pressure and pulse rate in young adults to see whether the differences, if they exist, can be explained by differences in body mass index, lifestyle, psychological, and socioeconomic characteristics. Data used were from the baseline examination of the Coronary Artery Risk Development in (Young) Adults Study (CARDIA). CARDIA is a longitudinal study of lifestyle and evolution of cardiovascular disease risk factors in 5,116 young adults, black and white, men and women, aged 18-30 years, of varying socioeconomic status. Young black adults had higher mean systolic blood pressure and slightly higher mean diastolic blood pressure than young white adults. For both men and women, the blood pressure differences between blacks and whites tended to be greater for the age group 25-30 than for the age group 18-24 years. Among the variables studied, body mass index, duration of exercise on the treadmill, number of cigarettes smoked per day, and number of alcoholic drinks per week were consistently associated with blood pressure. The blood pressure differences were greatly reduced after adjusting for these variables. Black participants had lower mean pulse rate than white participants. The differences tended to be greater for the age group 18-24 than for the age group 25-30 years. Among the variables studied, only duration on treadmill and number of cigarettes smoked per day were consistently correlated with pulse rate. With adjustment for duration on treadmill, the differences in pulse rate increased. These results suggest that differences in ethnic pattern of blood pressures and pulse rate with age may be due in part to obesity, physical fitness, alcohol consumption, and cigarette smoking.

Serum lipid response to a fat-modified, oatmeal-enhanced diet

The purpose of this study was to confirm and extend previous findings that serum cholesterol response to a fat-modified diet is enhanced by oat fiber. Participants (n = 236) were recruited from the Continental Illinois National Bank in Chicago. Data including weight, serum lipid level, lipoproteins, and 3-day food records were collected at baseline and every 4 weeks for 12 weeks. All participants were instructed to follow the fat-modified (Phase II) diet recommended by the American Heart Association (AHA). After 4 weeks, participants were randomly assigned to one of two groups. While both groups continued to follow the AHA diet, Group 1 was instructed to include 2 oz (56 g, dry wt) of oatmeal, isocalorically substituted for other carbohydrate foods. Group 2 served as the control and consumed no oat products throughout the study. Serum cholesterol values at baseline and after 4 weeks of the AHA diet were similar for both groups (203.9 and 193.0 mg/dl for Group 1 and 205.3 and 194.5 mg/dl for Group 2). After 4 weeks of oatmeal intervention, mean group differences were -6.8 and -2.1 mg/dl (P = 0.008 one-tailed t test) for Groups 1 and 2, respectively. Following an additional 4 weeks of oatmeal intervention, the Group 1 mean cholesterol increased slightly (0.9 mg/dl), while the Group 2 level decreased slightly (-0.7 mg/dl). Overall serum cholesterol responses for the two groups from Visit 2 to Visit 4 were -6.0 and -2.8 mg/dl for Groups 1 and 2, respectively (P = 0.074, one tail). Changes in weight were small and nonsignificant. Subgroup analyses revealed greater reductions in serum cholesterol among participants with the highest baseline serum cholesterol (-8.0 mg/dl vs -1.7 mg/dl for Subgroups 1 and 2, respectively). These data support previous findings that inclusion of oatmeal in a fat-modified diet is helpful in lowering serum cholesterol, particularly for individuals with elevated serum cholesterol levels.

Hematologic evidence of fetal hypoxia among newborn infants at high altitude in Bolivia

The reduced birth weight widely reported for high-altitude infants has been attributed to intrauterine hypoxia. This assertion may be tested by comparing hematologic values of high-altitude and low-altitude newborn infants, since the human fetus can respond to intrauterine hypoxia with enhanced erythropoiesis. This report presents cord blood values of term Bolivian infants classified by altitude, ethnic group, and parity: 105 from La Paz (3600 m) and 46 from Santa Cruz (400 m). Hematocrit, hemoglobin concentration, and the proportion of hemoglobin F are higher among newborn infants at high altitude. Ethnic group and parity interact with altitude in effect on hematocrit and hemoglobin concentration. Gestational age, birth weight, maternal hematologic variables, and socioeconomic indicators are not significantly associated with cord blood values. The high-altitude newborn infant displays evidence of enhanced erythropoiesis, which supports the suggestion that the high-altitude fetus experiences a greater degree of hypoxia in utero than does the low-altitude fetus.