Carol Ballew

Prevalence of Exclusive Breastfeeding Among US Infants: The Third National Health and Nutrition Examination Survey (Phase II, 1991–1994)

Because of the recognized benefits of exclusive breastfeeding,1–7 the American Academy of Pediatrics and the World Health Organization strongly encourage exclusive breastfeeding for the first 6 months of life.7,8 Unfortunately, national goals for exclusive breastfeeding in the United States are not yet established, at least in part because of a lack of data. n nThe Third National Health and Nutrition Examination Survey (NHANES III) sample is nationally representative and particularly valuable in providing data on exclusive breastfeeding. We used NHANES III data to examine the prevalence of exclusive breastfeeding among US infants to obtain baseline data for program evaluation and public health policymaking.

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

OBJECTIVEnTo assess the association between lead exposure and childrens physical growth.nnnDESIGNnCross-sectional analysis of data from the Third National Health and Nutrition Examination Survey, 1988-1994.nnnPARTICIPANTSnA total of 4391 non-Hispanic white, non-Hispanic black, and Mexican-American children age 1 to 7 years.nnnMEASUREMENTS AND RESULTSnWe 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.nnnCONCLUSIONSnThe 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.

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.

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 ≥20 years; 5790 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.

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.

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.

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.

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

ABSTRACT 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 × 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 ≤ .001) and less surgically induced cylinder at two days and one week postoperatively (P ≤ .02). The 5.5 mm and 6.5 mm incision cases did not differ significantly in visual acuity or astigmatism at any examination.

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

OBJECTIVEnTo 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.nnnSTUDY DESIGNnUsing 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.nnnRESULTSnMore 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).nnnCONCLUSIONSnModerate-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.

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

ABSTRACT 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 bestcorrected 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.