This proposal addresses the compelling public health issue of the problem of childhood obesity in the Hispanic (Mexican-American) population. In this context, one of the most striking epidemiological observations is that Hispanic immigrants in the U.S. exhibit a progressive and pronounced decline in health (obesity/ adiposity) over time and across generations that is evident even after accounting for socioeconomic status. The prevailing paradigm invokes the construct of acculturation (post-migration acquisition of host culture and/or loss of heritage culture) and posits this health decline is a biological consequence of some of acculturation?s psychosocial and behavioral sequelae (increasing stress, declining social ties, adoption of unhealthy diet). However, research has overlooked one crucial point: a major feature of this phenomenon is its intergenerational component, and yet intergenerational transmission is unaddressed. Our proposal seeks to address this important limitation. We propose that the cause of the observed intergenerational escalation in obesity among Mexican-Americans may, in part, originate during the intrauterine period of life. At this time, maternal acculturation-related processes may impact fetal development to produce phenotypic alterations in the structure and function of cells, tissues and organ systems that increase susceptibility for obesity/adiposity (i.e., the concept of ?fetal/developmental programming of health and disease risk?). We propose to conduct a prospective, longitudinal study in a representative cohort of N=300 first- and second- generation Mexican-American mothers and their offspring from early gestation through birth till 6-month age. We will conceptualize, operationalize and analyze acculturation as a multi-dimensional construct. We will quantify child adiposity (% fat mass) at birth and at 6-mo age by dual-energy X-ray absorptiometry (DXA) whole-body imaging. We will address the following specific aims:
Aim 1 : Test the hypothesis that maternal acculturation is prospectively associated with newborn and infant body composition (adiposity).
Aim 2 : Test the hypothesis that gestational endocrine (cortisol, CRH), immune (IL-6, TNF-?, CRP), oxidative (5-iPF2?-VI), and metabolic (glucose, insulin) biology across pregnancy mediates the effect of maternal acculturation on newborn and infant body composition (adiposity).
Aim 3 : Identify and quantify the potentially modifiable maternal psychological, behavioral and biophysical characteristics that are associated with acculturation and may account for its impact on gestational biology and child body composition (adiposity). We have assembled an interdisciplinary team of established investigators with complementary expertise; performed a feasibility analysis documenting our ability to recruit and retain the proposed study population and implement all elements of the study protocol; and collected and present preliminary data in support of the key tenets of our proposal. Our study will generate new information about the health of Mexican Americans, shed more light on the causes and mechanisms of intergenerational cycles of vulnerability, and provide a basis for developing specific translational targets for future intervention studies.

Public Health Relevance

The state of current and future health of Mexican-Americans in the United States is a major public health issue. Epidemiologic observations have consistently documented that individuals of Mexican origin living in the U.S. exhibit a progressive and pronounced decline in health over time and across generations, warranting considerable concern. The reason for this decline, particularly across generations, is not well understood. Our proposed project will test the hypothesis that among first- and second-generation Mexican-American women, maternal acculturation and acculturation- related processes may play a key role in influencing the in utero growth and development of her child via biological pathways to produce this intergenerational effect. We expect the results of the study to provide new information about the relative importance of various acculturation-related processes that mediate this effect and identify subgroups of women who may be particularly vulnerable. Thus, this project will addresses a scientific and public health issue of considerable importance and may suggest new avenues for early identification of at-risk individuals and provide directions for the subsequent development and testing of prevention and intervention strategies at the individual, family and community level, in order to limit the intergenerational perpetuation of disadvantage and poor health.

Agency
National Institute of Health (NIH)
Institute
National Institute on Minority Health and Health Disparities (NIMHD)
Type
Research Project (R01)
Project #
5R01MD010738-05
Application #
9878911
Study Section
Biobehavioral Mechanisms of Emotion, Stress and Health Study Section (MESH)
Program Officer
Rajapakse, Nishadi
Project Start
2016-07-13
Project End
2021-02-28
Budget Start
2020-03-01
Budget End
2021-02-28
Support Year
5
Fiscal Year
2020
Total Cost
Indirect Cost
Name
University of California Irvine
Department
Psychiatry
Type
Schools of Medicine
DUNS #
046705849
City
Irvine
State
CA
Country
United States
Zip Code
92617
Fox, Molly; Thayer, Zaneta; Wadhwa, Pathik D (2017) Acculturation and health: the moderating role of socio-cultural context. Am Anthropol 119:405-421
Ikenoue, Satoru; Waffarn, Feizal; Ohashi, Masanao et al. (2017) Prospective association of fetal liver blood flow at 30 weeks gestation with newborn adiposity. Am J Obstet Gynecol 217:204.e1-204.e8
Lindsay, Karen L; Buss, Claudia; Wadhwa, Pathik D et al. (2017) The Interplay between Maternal Nutrition and Stress during Pregnancy: Issues and Considerations. Ann Nutr Metab 70:191-200
Fox, Molly; Thayer, Zaneta; Wadhwa, Pathik D (2017) Assessment of acculturation in minority health research. Soc Sci Med 176:123-132