Mexican Americans (MAs), the fastest-growing minority in the State of Texas, have the highest birth rate of Hispanic adolescents, ages 15-19, have high levels of abdominal obesity and high blood pressure, with risk for later metabolic and cardiovascular diseases, and suffer disproportionately from type 2 diabetes mellitus, cardiovascular disease, and polycystic ovary syndrome. Pubertal timing (one’s development in relation to peers) and tempo (one’s rate of acceleration through puberty) or PTT are universal phenomena that may play an important role in the onset of these chronic diseases, the development of mental health problems such as depression and substance abuse, and contribute to the initiation of risky sexual behaviors that lead primarily to unplanned pregnancies, fertility problems, reproductive cancers and sexually transmitted infections. Early diagnosis and treatment of chronic diseases, mental health problems, and risky sexual behaviors among Mexican American children and adolescents are thus warranted. Current understanding of PTT in this population has been hampered by an absence of prospective, longitudinal studies, few samples of MA children and adolescents, few objective measures of pubertal development, and few studies that include both males and females. A greater understanding of PTT in this population is needed to facilitate early diagnosis of chronic diseases and to develop and test interventions that assist MAs in managing these chronic illnesses and in limiting their sexual health-risk behaviors. This need is especially great in rural areas where access to healthcare services is limited. The specific aims are to: (1) Document sex, age, and hormonal changes in PTT of MA boys and girls ages 6-14 years who live in rural areas of Southwest Texas; (2) Determine the effects of putative social determinants of health on PTT in rural MA boys and girls over time, controlling for comorbidities within the individual child/adolescent; and (3) Explore how endocrine-disrupting chemicals in the environment are related to PTT in rural MA boys and girls. The multidisciplinary research team has a wealth of experience and expertise in examining individual, family, and environmental factors contributing to health disparities of MA adolescents.
Methods:
Premises. The study is based on the following premises: (a) very little is known about the process of PTT in MA children and adolescents. (b) Ethnic minorities of Mexican descent are the fastest-growing minority population in the State of Texas. (c) This population suffers disproportionately from chronic diseases related to their social and environmental circumstances, which likely contribute to PTT, in part because those in rural areas lack health insurance and access to healthcare services.
Conceptual Framework. This study is framed by an ecological development model that can be depicted by three nested systems: the individual, the family, and the environment. In the figure below, the PTT of the individual is affected by factors from each of these interrelated systems; it unfolds over time. PTT may be affected by comorbidities in the individual that include T2DM, CVD, PCOS, depressive symptoms, substance use, and risky sexual behaviors leading to unplanned pregnancy, and STIs, which we will explore longitudinally.
Design: Cross-sectional, feasibility. Aims: (1) determine the feasibility of recruiting Mexican-American children and adolescents between 6 and 16 years of age and one of their parents/guardians via a rural health clinic to determine their willingness to have their children enrolled in a study about pubertal development at the clinic, and (2) determine the individual (e.g., hormonal levels) and family factors (e.g., chronic illness history, family communication and satisfaction, neighborhood quality and safety) that may be related to puberty and the onset of chronic illnesses.
Results:
A total of 22 Mexican-A children and adolescents (11 males and 11 females, aged 6-16 years) plus 22 parents (1 father and 21 mothers) were recruited. This sample represented a 100% response rate. Physical examinations and self-report instruments were completed by each child and adolescent who participated. Blood samples for DHEA-S and hormonal indicators of puberty were taken from each child/adolescent participant; each of these participants also supplied a first-voided morning urine specimen for detection of phthalates. Scales concerning parents’ communication, satisfaction with family, etc. were completed by each parent. All laboratory measurements, including abnormal findings, were shared with the participant and his/her primary care provider with consent. The findings were explained to the child/adolescent and his/her parent/guardian. This provided for appropriate review, management and referral.
Conclusion:
Rural Mexican-American children and adolescents who sought healthcare services from a primary care-based rural health clinic were willing to participate in the study. There were no refusals and no complaints about the study procedures. These findings provide evidence for feasibility for study methods.