Browsing by Subject "Puberty"

Now showing 1 - 4 of 4
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    Can relational aggression and victimization help to explain the emergence of the sex difference in depression during adolescence?
    (2012-08) Mathieson, Lindsay Catherine
    The current study investigated the contributions of relational aggression and victimization to the sex difference in adolescent depressive symptoms. In addition, pubertal development and both rumination and co-rumination were examined as potential contributing factors. A total of 499 sixth, seventh, and eighth grade students and their teachers participated in the current study. Relational aggression and victimization were assessed by teacher-reports, and all other constructs were measured by self-reports. Surprisingly, no sex differences in depressive symptoms were found. Relational aggression was associated with depressive symptoms, but only when rumination about victimization experiences was high. Relational victimization was associated with depressive symptoms, and this association was partially mediated by rumination about victimization experiences. Neither pubertal status nor timing interacted with relational aggression or victimization to predict depressive symptoms. Therefore, rumination about victimization experiences appears to play an important role in the associations between relational aggression and depressive symptoms and between relational victimization and depressive symptoms. The practical implications of these findings are discussed and recommendations are offered for future research.
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    Early Pubertal Development and Cardiometabolic Risk: A Life Course Approach
    (2013-09) Dreyfus, Jill
    A number of reports have linked early pubertal development to adverse health conditions among women. Despite race disparities in pubertal timing and later cardiovascular disease (CVD)-related health in adulthood, few studies have investigated if associations of early maturation with cardiometabolic risk factors differ for African-American and white women. Furthermore, there are limited longitudinal data tracking the trajectory of change in cardiometabolic risk factors after puberty and into adolescence and adulthood. The three primary aims of this thesis were to 1) examine the relationship between earlier age at menarche and CVD risk factors at different points in the life course, 2) account for the role of adiposity in associations, and 3) explore possible race differences in associations. These aims were explored using data from three prospective cohort studies that included different age groups: the National Growth and Health Study (NGHS) for ages 9-19 years, the Coronary Artery Risk Development in Young Adults (CARDIA) study for ages 18-54 years, and the Atherosclerosis Risk in Communities (ARIC) study for ages 45-75 years. The results from the three manuscripts included in this thesis suggested that earlier age at menarche was associated with a more adverse cardiometabolic profile over the life course, but higher lifetime accumulated adiposity among early maturing women explained most associations. Earlier menarche was more strongly related to adulthood adiposity and metabolic syndrome among white compared with African-American women, but there were no other differences by race. Targeted efforts to prevent obesity starting before puberty, as well as among early maturing girls even if normal weight, might be helpful for primordial prevention of cardiovascular disease.
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    Early puberty: adulthood metabolic consequences and childhood nutritional determinants
    (2013-07) Mueller, Noel Theodore
    Background: Accumulating evidence suggests puberty is occurring earlier today than ever before. Pubertal timing may be a harbinger for abnormal metabolic health. Thus, identifying its upstream determinants and downstream metabolic health consequences may provide an avenue to primordial prevention. The objective of this dissertation was to investigate pubertal timing in relation to type 2 diabetes (T2D), adipose depots, non-alcoholic fatty liver disease (NAFLD), and early-life nutrition. Methods: This dissertation includes three separate but related research manuscripts. The first aimed to investigate pubertal timing and T2D in a Brazilian adult population (35-74y) who were born and came of age before the rise of overweight and obesity in Brazil. The second examined pubertal timing in relation NAFLD and fat depots in a biracial cohort of young adults (18-30 years at entry, 42-56 years at measurement of NAFLD) from the Coronary Artery Risk Development In Young Adults (CARDIA) study. Finally, the third paper determined the role of diet quality and risk of early pubertal timing in a biracial sample of girls (9-10 years) from the National Heart, Lung, and Blood Institute Growth and Health Study (NGHS). Multivariable linear regression was used for continuous outcomes (glucose homeostasis measures, adipose depots, liver attenuation, and age at menarche) and Poisson regression to generate prevalence ratios (PR) and relative risks (RR) for dichotomous outcomes (T2D, NAFLD, and early menarche). In the last project, a diet quality score, derived by summing standard deviation scores for the densities of nutrients/chemicals indicative of prudent or Western dietary patterns, was analyzed in relation to incident early menarche. Results: In the first paper: early menarche [<11 years vs. 13-14 years (reference)] was associated with 22% (95% confidence interval: 3-42%) higher prevalence of T2D in Brazilian adults, adjusted for confounders and BMI at age 20 years. In the same model, a 1-standard deviation higher relative leg length (RLL), a marker of early life growth and maturation, was associated with a 10% (5-15%) and 11% (7-15%) lower prevalence of T2D in women and men, respectively. The association between RLL and T2D was stronger among females with earlier menarche (p for interaction on multiplicative scale = 0.02), and among adults who were overweight or obese at age 20 years (p for interaction on multiplicative scale = 0.02) or 35-74 years (p for interaction on multiplicative scale = 0.03). In the second paper: in CARDIA, a 1-year increment in age at menarche was associated with 10% (2-18%) lower prevalence of NAFLD, and inversely associated with visceral, subcutaneous, and intra-abdominal muscle fat, after adjusting for confounders and BMI measured at 18-30 years. RLL was also associated with these measures, but was attenuated after control for BMI. Lastly, in the third paper: a better diet quality was associated with lower risk of early menarche (<11 years) after adjustment for confounders and % body fat from skinfolds (1-SD increment in diet quality score, RR=0.77; 95% CI: 0.66-0.90). Conclusions: These results indicate that early menarche is associated with higher prevalence of diabetes in an adult Brazilian population that underwent nutritional transition after coming of age, and non-alcoholic fatty liver disease in a biracial U.S. population, after adjusting for potential early-life confounders and early adulthood BMI. Relative leg length, while only loosely associate with age at menarche, was inversely associated with T2D but not NAFLD. Age at menarche and relative leg length did not appear to be preferentially related to specific adipose depots. These markers likely represent unique aspects of early-life growth and maturation, and depend on the context of the population under study. The results of the final research paper suggest that risk for early menarche may be reduced through dietary modification, independent of fatness. In light of the secular trend toward earlier age at puberty in the U.S. and abroad, it is important that future research continues in this arena under the realm of primordial prevention. Continued research is needed to determine the extent to which early-life modifiable lifestyle factors, such as dietary patterns and physical activity, can influence long-term health and disease through effects on pubertal timing.
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    The relationship among culture-specific factors, pubertal timing, and body image and eating disordered symptoms among adopted Korean adolescent girls.
    (2009-08) Song, Sueyoung L.
    The aim of this dissertation was to examine the role of developmental and culture-specific factors in body image concerns and eating disordered symptoms among internationally, transracially adopted adolescent girls. I specifically sought to replicate past research that suggested early pubertal timing was associated with eating disordered outcomes; to examine the association between racial, ethnic, and adoption factors and eating disordered outcomes; and to test whether these latter associations were moderated by pubertal timing in two samples of adopted female Korean Americans. Early menarche significantly predicted body dissatisfaction, but only in the second study. In the first study there were significant main effects of both birth preoccupation and racial discomfort on two of the body image and ED symptom outcomes - binge eating and weight preoccupation. The first study also revealed a significant main effect between cultural socialization and compensatory behaviors. In the second study, there were significant main effects of birth preoccupation on body satisfaction and ED symptoms. There also were significant main effects of both adoptive identity and ethnic identity on satisfaction with Asian appearances. Across both studies, there was no support for the hypothesis that age of menarche would moderate the association between culture-specific factors and eating disordered outcomes. The study findings provide a cultural framework to help uncover the process and mechanisms by which cultural differences in body image and ED symptoms may exist.