Covariate-adjusted Means Research Articles

Association of candy consumption with body weight measures, other health risk factors for cardiovascular disease, and diet quality in US children and adolescents: NHANES 1999–2004

Objective: The purpose of this study was to determine the effects of total, chocolate, or sugar candy consumption on intakes of total energy, fat, and added sugars; diet quality; weight/adiposity parameters; and risk factors for cardiovascular disease in children 2–13 years of age (n=7,049) and adolescents 14–18 years (n=4,132) participating in the 1999–2004 National Health and Nutrition Examination Survey.Methods: Twenty-four hour dietary recalls were used to determine intake. Diet quality was determined using the Healthy Eating Index-2005 (HEI-2005). Covariate-adjusted means, standard errors, and prevalence rates were determined for each candy consumption group. Odds ratios were used to determine the likelihood of associations with weight status and diet quality.Results: In younger children, total, chocolate, and sugar candy consumption was 11.4 g±1.61, 4.8 g±0.35, and 6.6 g±0.46, respectively. In adolescents, total, chocolate, and sugar candy consumption was 13.0 g±0.87, 7.0 g±0.56, and 5.9 g±0.56, respectively. Total candy consumers had higher intakes of total energy (2248.9 kcals±26.8 vs 1993.1 kcals±15.1, p<0.0001) and added sugars (27.7 g±0.44 vs 23.4 g±0.38, p<0.0001) than non-consumers. Mean HEI-2005 score was not different in total candy and sugar candy consumers as compared to non-consumers, but was significantly lower in chocolate candy consumers (46.7±0.8 vs 48.3±0.4, p = 0.0337). Weight, body mass index (BMI), waist circumference, percentiles/z-score for weight-for-age and BMI-for-age were lower for candy consumers as compared to non-consumers. Candy consumers were 22 and 26%, respectively, less likely to be overweight and obese than non-candy consumers. Blood pressure, blood lipid levels, and cardiovascular risk factors were not different between total, chocolate, and sugar candy consumers and non-consumers (except that sugar candy consumers had lower C-reactive protein levels than non-consumers).Conclusion: This study suggests that candy consumption did not adversely affect health risk markers in children and adolescents.

Do Breakfast Skipping and Breakfast Type Affect Energy Intake, Nutrient Intake, Nutrient Adequacy, and Diet Quality in Young Adults? NHANES 1999–2002

Objective: To assess the impact of breakfast skipping and type of breakfast consumed on energy/nutrient intake, nutrient adequacy, and diet quality.Design: Cross-sectional.Setting: The National Health and Nutrition Examination Survey (NHANES), 1999–2002.Subjects: Young adults (20–39 years, n = 2615).Measures: A 24-hour dietary recall was used, with breakfast defined as self-reported. Covariate-adjusted sample-weighted means for the entire day's energy/nutrient intakes, mean adequacy ratio (MAR) for nutrient intakes, and diet quality (i.e., Healthy Eating Index [HEI]-2005) scores were compared using analysis of variance and Bonferroni's correction (p < 0.0167) among breakfast skippers (BS), ready-to-eat-cereal breakfast consumers (RTECC), and other breakfast consumers (OBC). Energy/nutrient intakes and food consumption at breakfast were also compared (p ≤ 0.05).Results: Twenty-five percent of young adults were BS, 16.5% were RTECC, and 58.4% were OBC. Intakes of total energy, percent energy from carbohydrate, and dietary fiber were higher in RTECC than in BS and OBC. Percent energy intake from added sugars was higher in BS than in RTECC and OBC. Compared with BS and RTECC, OBC consumed a lower percent energy from carbohydrates and total sugars, but consumed a higher percent energy from total fat and discretionary solid fats and had a higher cholesterol intake. Intakes of several micronutrients were higher in RTECC than in BS and OBC. Both MAR and total HEI scores were the highest in RTECC and higher in OBC than in BS. The HEI scores for intakes of whole fruits, total/whole grains, milk, and percent energy from solid fat/alcohol/added sugar were the highest in RTECC and higher in OBC than in BS. Compared with OBC, RTECC had a higher HEI score for the intake of saturated fat. At breakfast, RTECC consumed higher intakes of total fruits, whole grains, dairy products, carbohydrates and total sugars, dietary fiber, and several micronutrients than OBC, who consumed higher intakes of meat/poultry/fish, eggs, total fat, discretionary oils/solid fats, cholesterol, and sodium than RTECC.Conclusion: Thus, RTECC had more favorable nutrient intakes and better diet quality than BS and OBC.

The Relationship of Breakfast Skipping and Type of Breakfast Consumption with Nutrient Intake and Weight Status in Children and Adolescents: The National Health and Nutrition Examination Survey 1999-2006

Background National data comparing nutrient intakes and anthropometric measures in children/adolescents in the United States who skip breakfast or consume different types of breakfasts are limited. Objective To examine the relationship between breakfast skipping and type of breakfast consumed with nutrient intake, nutrient adequacy, and adiposity status. Subjects Children aged 9 to 13 years (n=4,320) and adolescents aged 14 to 18 years (n=5,339). Design Cross-sectional data from the National Health and Nutrition Examination Survey 1999-2006. Methods Breakfast consumption was self-reported. A 24-hour dietary recall was used to assess nutrient intakes. Mean adequacy ratio (MAR) for micronutrients and anthropometric indexes were evaluated. Covariate-adjusted sample-weighted means were compared using analysis of variance and Bonferroni's correction for multiple comparisons among breakfast skippers (breakfast skippers), ready-to-eat (RTE) cereal consumers, and other breakfast (other breakfast) consumers. Results Twenty percent of children and 31.5% of adolescents were breakfast skippers; 35.9% of children and 25.4% of adolescents consumed RTE cereal. In children/adolescents, RTE cereal consumers had lower intakes of total fat and cholesterol and higher intakes of total carbohydrate, dietary fiber, and several micronutrients ( P<0.05 for all) than breakfast skippers and other breakfast consumers. RTE cereal consumers had the highest MAR for micronutrients, and MAR was the lowest for breakfast skippers ( P<0.05). In children/adolescents, breakfast skippers had higher body mass index-for-age z scores ( P<0.05) and a higher waist circumference ( P<0.05) than RTE cereal and other breakfast consumers. Prevalence of obesity (body mass index ≥95th percentile) was higher in breakfast skippers than RTE cereal consumers ( P<0.05) in children/adolescents and was higher in other breakfast consumers than RTE cereal consumers only in adolescents ( P<0.05). Conclusions RTE cereal consumers had more favorable nutrient intake profiles and adiposity indexes than breakfast skippers or other breakfast consumers in US children/adolescents.

Exposure of the U.S. Population to Acrylamide in the National Health and Nutrition Examination Survey 2003–2004

BackgroundThe lifelong exposure of the population to acrylamide has raised concerns about the possible health effects of the chemical. Data on the extent of exposure to acrylamide and its primary metabolite, glycidamide, are needed to aid in the assessment of potential health effects.ObjectivesThe aim of this study was to assess human exposure to acrylamide and glycidamide in the general U.S. population through the measurement of hemoglobin adducts of acrylamide (HbAA) and glycidamide (HbGA).MethodsHbAA and HbGA were measured in 7,166 subjects from the National Health and Nutrition Examination Survey. Stratified HbAA and HbGA data were reported by sex, age groups, race/ethnicity (Mexican American, non-Hispanic black, non-Hispanic white), and smoking status based on serum cotinine levels. Covariate-adjusted geometric means for each demographic group were calculated using multiple regression analysis.ResultsHbAA and HbGA levels ranged from 3 to 910 and from 4 to 756 pmol/g hemoglobin, respectively, with smokers having the highest levels overall. Tobacco smoke exposure in nonsmokers had a small but significant effect on HbAA and HbGA levels. Adjusted geometric mean levels for children 3–11 years of age were higher than for adults ≥ 60 years of age [mean (95% confidence interval): HbAA, 54.5 (49.1–51.5) and HbGA, 73.9 (71.3–76.6) vs. HbAA, 46.2 (44.3–48.2) and HbGA, 41.8 (38.7–45.2)]. Levels were highest in Mexican Americans [HbAA: 54.8 (51.9–57.8), HbGA: 57.9 (53.7–62.5)], whereas non-Hispanic blacks had the lowest HbGA levels [43.5 (41.1–45.9)].ConclusionsU.S. population levels of acrylamide and glycidamide adducts are described. The high variability among individuals but modest differences between population subgroups suggest that sex, age, and race/ethnicity do not strongly affect acrylamide exposure. Adduct concentration data can be used to estimate relative exposure and to validate intake estimates.

Levels of urinary total and speciated arsenic in the US population: National Health and Nutrition Examination Survey 2003–2004

To provide levels of total and speciated urinary arsenic in a representative sample of the US population. For the first time, total arsenic and seven inorganic and organic arsenic species were measured in the urine of participants (n=2557) for the 2003-2004 National Health and Nutrition Examination Survey (NHANES). Data were compiled as geometric means and selected percentiles of urinary arsenic concentrations (microg/l) and creatinine-corrected urinary arsenic (microg/g creatinine) for total arsenic, dimethylarsinic acid, arsenobetaine, and a sum of the inorganic related species. Arsenic acid, arsenous acid, arsenocholine, and trimethylarsine oxide were detected in 7.6%, 4.6%, 1.8%, and 0.3% of the participants, respectively (the limits of detection of 0.6-1.2 microg/l). Monomethylarsonic acid was detected in 35% of the overall population. For all participants aged > or =6 years, dimethylarsinic acid (geometric mean of 3.71 microg/l) and arsenobetaine (geometric mean of 1.55 microg/l) had the greatest contribution to the total urinary arsenic levels. A relatively greater percentage contribution from arsenobetaine is seen at higher total urinary arsenic levels and from dimethylarsinic acid at lower total urinary arsenic levels. For all participants aged > or =6 years, the 95th percentiles for total urinary arsenic and the sum of inorganic-related arsenic (arsenic acid, arsenous acid, dimethylarsinic acid, and monomethylarsonic acid) were 65.4 and 18.9 microg/l, respectively. For total arsenic and dimethylarsinic acid, covariate-adjusted geometric means demonstrated several slight differences due to age, gender, and race/ethnicity. The data reflect relative background contributions of inorganic and seafood-related arsenic exposures in the US population. Arsenobetaine and dimethylarsinic acid are the major arsenic species present with arsenobetaine, accounting for a greater proportion of total arsenic as total arsenic levels increase.

Economic and clinical disparities in hospitalized patients with type 2 diabetes.

To identify and describe economic and clinical relationships and trends associated with selected access, equity, and outcome characteristics of a large inpatient population with Type 2 diabetes. Longitudinal, descriptive cross-sectional study with secondary analyses of data about 101,944 patients in hospitals in the United States (US), 40 years of age and older with a primary diagnosis of Type 2 diabetes from the Health Care Cost and Utilization Project (HCUP-3) database for 1994-1997. Descriptive analysis, hierarchical, random-effects regression modeling, and contrasts between covariate-adjusted means. Hospital charge data were highly skewed in a positive direction requiring a logarithmic transformation. Variables for the study included both hospital and patient characteristics. Significant racial and sex disparities were found in health care access, equity, and outcomes, with equity characteristics showing alarming disparities in types of procedures (amputations and peripheral vascular bypass grafts) performed, lengths of stay, and dispositions. Disparities in health care access, equity, and outcomes continue to exist on the basis of sex, ethnicity, and age as well as the type and location of the hospital. Access and equity are values that, despite rhetoric in relation to health care utilization, have not been systematically attained.

Influence of reporting error on the relation between blood folate concentrations and reported folic acid–containing dietary supplement use among reproductive-aged women in the United States

Folic acid intake is the most important predictor of blood folate concentrations among nonpregnant women, but the reporting of folic acid-containing supplement use is subject to error. We assessed the effect of reporting error of supplement use on blood folate concentrations. Data from the third National Health and Nutrition Examination Survey were analyzed. Respondents to that survey were asked twice about supplement use: ie, during the household interview, to recall use in the previous month, and during the physical examination, to recall use in the previous 24 h. To examine the effect of error reporting, we classified women (aged 15-44 y) into 5 groups according to supplement use in the previous month (nonusers, those ingesting < 400 micro g/d, and those ingesting >or= 400 micro g/d) and in the 24 h before the physical examination (yes or no). We expected nonappreciable differences in red blood cell (RBC) folate concentration by status of 24-h recall within the same category of previous-month use because RBC folate reflects long-term average consumption. We calculated covariate-adjusted means of serum and RBC folate concentrations. Among women who reported average daily use of >or= 400 micro g folic acid in the previous month, the adjusted mean RBC folate was 436.5 nmol/L (95% CI: 406.7, 466.3 nmol/L) in those who did not take the supplement in the previous 24 h and 519.7 nmol/L (95% CI: 496.2, 543.2 nmol/L) in those who did do so (P < 0.01). This significant difference indicates apparently erroneous reporting of supplement use in the previous month by some participants. The effect of reporting error on blood folate concentrations is important in interpreting survey results, evaluating health education campaigns, and identifying populations needing special education programs.

Weekly Balancing Crude Protein in Diets for Holstein Cows Throughout Lactation Using One Versus Two Grains

Holstein cows (n = 72, 28 primiparous) were fed for ad libitum intake a forage mixture (corn and haycrop silages, 63:37 DM) and a 71:29 ratio of two grain mixtures (13.8 and 36.2% CP, DM basis) at 1 kg/2.5kg of the previous day's milk during 1 to 28 DIM (covariate period). Thereafter, rations were balanced and adjusted for energy and CP weekly based on monthly DHI data, forage analyses, and NRC requirements. Cows were blocked by parity (1 vs. >1) and assigned randomly to receive one grain (blend of 13.8 and 36.2% CP grains, herd mean) or two grains according to individual needs. Daily yields of milk, 4% FCM, SCM. and resulting intakes of grain were higher for cows fed two grains, but the increase in daily DMI and the decreases in daily forage intake and SCM:grain ratio were not significant. Fewer pluriparous cows (3 vs. 8 out of 19) on the two-grain treatment conceived after first service, but overall services per conception (1.97) were equal. Percentage of cows with SCC below linear score 4 (91%) was equal between treatments. Means adjusted by covariate 4% FCM resulted in more modest treatment effects. Advantage of two-grain versus one-grain treatment for milk per day was 7.7% for parity 1 and only 1.6% for parities >1; corresponding responses (nonsignificant) for 4% FCM were 2.8 and 4.3, respectively. Forage DMI depressions on two-grain treatment were not significant. When covariate-adjusted means were used, the advantage in income over feed cost for individualized feeding of CP was $106 and $36/yr per cow in parities 1 and >1 when cows produced 8209kg (313 DIM) and 8527kg (320 DIM) of milk, respectively.

The interacting effects of siphon nipping and habitat on bivalve ( Mercenaria mercenaria (L.)) growth in a subtropical seagrass ( Halodule wrightii Aschers) meadow

Seagrasses may provide protection from predation while also influencing food supply for suspension-feeders by reducing water flow and changing rates of particle deposition. However, prior studies have shown both increased and decreased rates of bivalve growth in seagrass habitats relative to unvegetated substrata. We examined the hypothesis that variation in rates of siphon nipping and its consequences might partially explain these conflicting results. A 2-month field experiment was undertaken to examine the interacting effects of habitat (sand vs. grass) and siphon nipping on the growth of the suspension-feeding bivalve Mercenaria mercenaria (L.). To simulate the effects of siphon nipping on growth we anesthetized clams and nipped (excised) a standardized portion of their siphons. We compared shell growth in length, axis of maximum growth and breadth of siphon-nipped vs. unnipped clams in enclosures both in seagrass ( Halodule wrightii Aschers) and adjacent sand habitats in inshore Alabama waters. Significant growth differences in mean clam length and axis of maximum growth were observed with growth greatest in unnipped sand individuals, followed by unnipped grass individuals, nipped sand individuals and nipped grass individuals. By two-way ANOVA (main effects of siphon condition and habitat type) only siphon condition was significant. For covariate-adjusted means using initial size as the covariate, ordered results were identical, except for nipped clams in grass which did not differ significantly from those in sand. Minor differences were detected among treatments using clam breadth. Because excised siphon tissue accounted for only a few percent of the total dry tissue weight, we hypothesize that regeneration costs and reduced feeding efficiency together may explain the significant differences observed between nipped and unnipped treatments. Our results may explain previous conflicting accounts which did not control for potential differences in siphon nipping.