Dulaglutide and Glomerular Hyperfiltration, Proteinuria, and Albuminuria in Youth With Type 2 Diabetes: Post Hoc Analysis of the AWARD-PEDS Study.

OBJECTIVE: To examine changes in glomerular hyperfiltration and other measures of kidney function in youth with type 2 diabetes treated with dulaglutide or placebo. RESEARCH DESIGN AND METHODS: Post hoc analysis was performed on kidney laboratory data from 154 youths (age 10-18 years) with type 2 diabetes enrolled in a completed placebo-controlled glycemic control trial of dulaglutide. RESULTS: Mean estimated glomerular filtration rate (eGFR) decreased from baseline to 26 weeks in participants treated with dulaglutide versus placebo (-5.8 vs. -0.1 mL/min/1.73 m2; P = 0.016). Decreases in eGFR were observed primarily in participants with baseline glomerular hyperfiltration. At 26 weeks, the prevalence of both glomerular hyperfiltration and proteinuria increased with placebo but decreased with dulaglutide (P = 0.014 and 0.004 vs. placebo, respectively). CONCLUSIONS: Dulaglutide was associated with attenuated glomerular hyperfiltration and proteinuria in youth with type 2 diabetes. The impact of these changes on the risk of diabetic kidney disease is unclear.

Associations between body mass index and body composition measures in a birth cohort.

BACKGROUND: Associations among body composition measures have been limited to cross-sectional analyses of different subjects. We identified cross-sectional relationships between body mass index (BMI) and other body composition measures and predicted body composition measures from BMI throughout childhood and adolescence. METHODS: BMI was calculated and % body fat (%BF), fat mass index (FMI), and fat-free mass index (FFMI) were measured using dual-energy x-ray absorptiometry at ages 5, 9, 11, 13, 15, and 17 years in a birth cohort (n = 629). Sex-specific body composition measures were calculated for BMI-for-age percentiles; associations between BMI and body composition measures were characterized; and body composition measures were predicted from BMI. RESULTS: %BF, FMI, and FFMI generally increased with BMI-for-age percentiles at each age. Correlations between BMI and %BF or FMI were generally higher at BMI-for-age percentiles ≥95% than for lower BMI-for-age percentiles. Correlations between BMI and FFMI were generally higher for participants at very low and very high BMI-for-age percentiles than at moderate BMI-for-age percentiles. Age- and sex-specific predictions from BMI are provided for %BF, FM, and FFMI. CONCLUSIONS: Sex-specific body composition measures throughout childhood and adolescence are presented. BMI is a better indicator of adiposity at higher than at lower BMI values. IMPACT: Sex-specific body composition measures throughout childhood and adolescence are described. % BF, FMI, and FFMI generally increased with BMI-for-age percentiles for both sexes throughout childhood and adolescence. BMI is a better indicator of adiposity at higher BMI levels than at lower BMI values throughout childhood and adolescence.

Beverage Intakes and Toothbrushing During Childhood Are Associated With Caries at Age 17 Years.

BACKGROUND: Sugar-sweetened beverages (SSBs) have been associated with childhood caries; however, associations among lifelong beverage intakes and adolescent caries have received less attention. OBJECTIVE: To investigate associations between beverage intakes during childhood and adolescence and caries experience at 17 years of age, while adjusting for fluoride intakes and toothbrushing. DESIGN: Descriptive model analyses were conducted on data collected from a longitudinal birth cohort study. PARTICIPANTS/SETTING: Participants included Iowa Fluoride Study members (n = 318) recruited at birth between 1992 and 1995 with at least 6 beverage questionnaires completed from ages 1 to 17 years and a caries examination at age 17. EXPOSURE: Predictors included mean daily milk, juice (100% juice and juice drinks before age 9), SSB (including juice drinks after age 9), and water/sugar-free beverage (SFB) intakes; daily fluoride intakes; and daily toothbrushing frequencies for ages 1 to 17. MAIN OUTCOME MEASURES: The outcome was dental caries count at age 17, adjusted for the number of scored tooth surfaces (decayed and filled surfaces attack rate [DFSAR]). STATISTICAL ANALYSES PERFORMED: Univariable generalized linear models were fit for each predictor and the outcome DFSAR. Multivariable models assessed combined effects of beverage types, fluoride variables, toothbrushing, sex, and baseline socioeconomic status. RESULTS: Based on multivariable models, each 8 oz of additional daily juice and water/SFB decreased expected DFSAR by 53% (95% confidence interval [CI]: 17%-73%) and 29% (95% CI: 7%-46%), respectively, and 8 additional oz SSBs increased expected DFSAR by 42% (95% CI: 5%-92%), after adjustment for other beverage intakes, toothbrushing, total fluoride intake excluding SSB fluoride (non-SSB total fluoride), sex, and baseline socioeconomic status. Each additional daily toothbrushing event decreased expected DFSAR by 43% (95% CI: 14%-62%) after adjustment for beverage intakes, non-SSB total fluoride intake, sex, and baseline SES. CONCLUSIONS: Higher juice and water/SFB intakes and more toothbrushing were associated with lower caries at age 17, while higher SSB intakes were associated with higher caries.

Identification of and Associations among Low, Middle, and High Body Composition Trajectories from Age 5- to 17-Years.

Our objective was to identify sex-specific age 5- to 17-year body composition (body mass index (BMI), % body fat, fat mass index, fat-free mass index) trajectories, compare trajectories assigned using age 5 (AGE5) data to those assigned using all available (ALL) data, and compare BMI assignments to other body composition assignments. Cluster analysis was used to identify low, medium, and high trajectories from body composition measures obtained from dual energy x-ray absorptiometry (DXA) scans at 5, 9, 11, 13, 15, and 17 years in a birth cohort followed longitudinally (n = 469). Moderate agreement was observed for comparisons between AGE5 data and ALL data cluster assignments for each body composition measure. Agreement between cluster assignments for BMI and other body composition measures was stronger using ALL data than using AGE5 data. Our results suggest that BMI, % body fat, fat mass index, and fat free mass index trajectories are established during early childhood, and that BMI is a reasonable predictor of body composition appropriate to track obesity in public health and clinical settings.

Child and Adolescent Sugar-Sweetened Beverage Intakes Are Longitudinally Associated with Higher Body Mass Index z Scores in a Birth Cohort Followed 17 Years.

BACKGROUND: Sugar-sweetened beverages (SSB) are considered a risk factor for obesity. OBJECTIVE: The objective of the current study was to investigate associations between the predictors of beverage and energy intakes and mean adequacy ratios (MARs), and the outcome of body mass index (BMI) z scores, in a birth cohort using longitudinal models. DESIGN: This was a longitudinal analysis of secondary data. PARTICIPANTS/SETTING: Participants in the Iowa Fluoride and Iowa Bone Development Studies with two beverage intake questionnaires completed between ages 2 and 4.7 years or 5 and 8.5 years or one questionnaire between ages 9 and 10.5, 11 and 12.5, 13 and 14.5, or 15 and 17 years (n=720); two food and beverage diaries completed between ages 2 and 4.7 years or 5 and 8.5 years or completion of the Block's Kids' Food Frequency Questionnaires at age 11, 13, 15, or 17 years (n=623); and anthropometric measures at the corresponding age 5-, 9-, 11-, 13-, 15-, or 17-year examination(s). PREDICTORS: Mean daily 100% juice, milk, SSB, water/sugar-free beverage, and energy intakes and MARs averaged over ages 2 to 4.7, 5 to 8.5, 9 to 10.5, 11 to 12.5, 13 to 14.5, or 15 to 17 years were predictors. OUTCOME: BMI z score was the outcome. STATISTICAL ANALYSES: Linear mixed models were fit for each beverage, energy, and MAR variable, with the beverage, energy, or MAR variable as the predictor and BMI z score as the outcome. Beverage models were adjusted for energy and MAR and baseline socioeconomic status. RESULTS: SSB intake adjusted for energy intake, MAR, and baseline socioeconomic status was associated with BMI z score; each additional 8 oz SSB consumed/day throughout childhood and adolescence increased the BMI z score an average 0.050 units (95% CI 0.022 to 0.079; P=0.001). Adjusted water/sugar-free beverage intake (0.026 units; 95% CI 0.006 to 0.046; P=0.013) was modestly associated with BMI z score, while 100% juice (-0.001 units; 95% CI -0.059 to 0.057; P=0.97) and milk (0.022 units; 95% CI -0.007 to 0.052; P=0.13) intakes were not associated with BMI z scores. CONCLUSIONS: Higher SSB intakes were associated with increased BMI z scores throughout childhood and adolescence in Iowa Fluoride Study participants. Public health initiatives targeting SSB consumption during childhood and adolescence remain relevant.

Description of Child and Adolescent Beverage and Anthropometric Measures According to Adolescent Beverage Patterns.

Our objective is to retrospectively describe longitudinal beverage intakes and anthropometric measures according to adolescent beverage patterns. Data were collected from Iowa Fluoride Study participants (n = 369) using beverage questionnaires at ages 2⁻17 years. Weight and height were measured at ages 5, 9, 13 and 17 years. Cluster analyses were used to identify age 13- to 17-year beverage patterns. Treating age and beverage cluster as explanatory factors, sex-specific generalized linear mixed models were used to identify when differences in beverage intakes and anthropometric measures began. Predominant beverage intakes were higher in each of the corresponding clusters by 9⁻12.5 years; females with high milk intakes during adolescence and males with high 100% juice or sugar-sweetened beverage intakes during adolescence reported higher intakes of that beverage beginning at 2⁻4.7 years. Females and males in the 100% juice cluster had lower weights than other clusters beginning at 13 years, while females and males in the neutral cluster were shorter beginning at 13 years. Females in the water/sugar-free beverage cluster had higher body mass indices (BMIs) beginning at 9 years. Females and males in the 100% juice cluster had lower BMIs beginning at 5 and 9 years, respectively. Childhood beverage intakes and growth patterns differ according to adolescent beverage patterns.

Higher Longitudinal Milk Intakes Are Associated with Increased Height in a Birth Cohort Followed for 17 Years.

Background: Height is an indicator of nutritional status; linear growth faltering has recognized consequences for cognitive, emotional, and chronic disease risk. Although height is routinely studied in developing countries, less attention is given to height in the United States. Objective: The objective of this study was to identify longitudinal associations between childhood and adolescent beverage intakes, nutrient adequacy, or energy intake and height in a birth cohort. Methods: Data for participants through ages 2-17 y (n = 717; 353 males, 364 females) recruited at birth for the longitudinal Iowa Fluoride Study (IFS) were used in the current cohort analyses. Beverage intakes (n = 708) were collected by beverage-frequency questionnaires at 3- to 6-mo intervals, whereas nutrient data (n = 652) were obtained from 3-d food diaries completed at 3- to 6-mo intervals through age 8.5 y and from Block Kids' food-frequency questionnaires at 2-y intervals after age 8.5 y. Nutrient adequacy ratios were calculated with the use of age- and sex-specific Estimated Average Requirements. Height was measured at clinic visits when the participants were approximately ages 5, 9, 11, 13, 15, and 17 y. Linear mixed models were used to identify longitudinal associations between dietary variables and height. A baseline model that adjusted for changing growth patterns during adolescence was established. Dietary and potential confounding variables were added to this baseline model. Results: Milk intake adjusted for mean adequacy ratio, energy intake, and baseline socioeconomic status was associated with height; for each additional 8 ounces (236 mL) of milk consumed per day throughout childhood and adolescence, height increased, on average, by 0.39 cm (95% CI: 0.18, 0.60 cm; P < 0.001). Conclusions: IFS participants' height increased by 0.39 cm for each additional 8 ounces (236 mL) of milk consumed throughout childhood and adolescence. The clinical implications of the mild linear growth faltering observed in healthy youth are unknown. This trial was registered at www.clinicaltrials.gov as 199112665.

Longitudinal associations between dental caries increment and risk factors in late childhood and adolescence.

OBJECTIVES: To assess longitudinal associations between permanent tooth caries increment and both modifiable and non-modifiable risk factors, using best subsets model selection. METHODS: The Iowa Fluoride Study has followed a birth cohort with standardized caries exams without radiographs of the permanent dentition conducted at about ages 9, 13, and 17 years. Questionnaires were sent semi-annually to assess fluoride exposures and intakes, select food and beverage intakes, and tooth brushing frequency. Exposure variables were averaged over ages 7-9, 11-13, and 15-17, reflecting exposure 2 years prior to the caries exam. Longitudinal models were used to relate period-specific averaged exposures and demographic variables to adjusted decayed and filled surface increments (ADJCI) (n = 392). The Akaike Information Criterion (AIC) was used to assess optimal explanatory variable combinations. RESULTS: From birth to age 9, 9-13, and 13-17 years, 24, 30, and 55 percent of subjects had positive permanent ADJCI, respectively. Ten models had AIC values within two units of the lowest AIC model and were deemed optimal based on AIC. Younger age, being male, higher mother's education, and higher brushing frequency were associated with lower caries increment in all 10 models, while milk intake was included in 3 of 10 models. Higher milk intakes were slightly associated with lower ADJCI. CONCLUSIONS: With the exception of brushing frequency, modifiable risk factors under study were not significantly associated with ADJCI. When possible, researchers should consider presenting multiple models if fit criteria cannot discern among a group of optimal models.

Dental caries clusters among adolescents.

OBJECTIVES: There have been very few longitudinal studies of dental caries in adolescents, and little study of the caries risk factors in this age group. The purpose of this study was to describe different caries trajectories and associated risk factors among members of the Iowa Fluoride Study (IFS) cohort. METHODS: The IFS recruited a birth cohort from 1992 to 1995, and has gathered dietary, fluoride and behavioural data at least twice yearly since recruitment. Examinations for dental caries were completed when participants were ages 5, 9, 13 and 17 years. For this study, only participants with decayed and filled surface (DFS) caries data at ages 9, 13 and 17 were included (N=396). The individual DFS counts at age 13 and the DFS increment from 13 to 17 were used to identify distinct caries trajectories using Ward's hierarchical clustering algorithm. A number of multinomial logistic regression models were developed to predict trajectory membership, using longitudinal dietary, fluoride and demographic/behavioural data from 9 to 17 years. Model selection was based on the akaike information criterion (AIC). RESULTS: Several different trajectory schemes were considered, and a three-trajectory scheme-no DFS at age 17 (n=142), low DFS (n=145) and high DFS (n=109)-was chosen to balance sample sizes and interpretability. The model selection process resulted in use of an arithmetic average for dietary variables across the period from 9 to 17 years. The multinomial logistic regression model with the best fit included the variables maternal education level, 100% juice consumption, brushing frequency and sex. Other favoured models also included water and milk consumption and home water fluoride concentration. The high caries cluster was most consistently associated with lower maternal education level, lower 100% juice consumption, lower brushing frequency and being female. CONCLUSIONS: The use of a clustering algorithm and use of Akaike's Information Criterion (AIC) to determine the best representation of the data were useful means in presenting longitudinal caries data. Findings suggest that high caries incidence in adolescence is associated with lower maternal educational level, less frequent tooth brushing, lower 100% juice consumption and being female.