Secondary Aims:
Secondary Aim 1. To explore whether maternal psychosocial factors (stress, depression and substance use), and household food/beverage security and/or constrained physical activity environments moderate FSN intervention impacts on: infant and young children's feeding behaviors; and, infant/young children's diets, PA patterns, and weight status.
Secondary Aim 2. To explore how maternal/infant characteristics, diet and behaviors impact the underlying biologic mechanisms of early childhood obesity, and whether social and behavioral interventions can impact infant metabolic health.
Aim 2a. At delivery, examine how measures of infant metabolic health (fasting glucose, insulin, leptin, adiponectin, lipids, and c-reactive protein) are a) correlated with maternal biologic measures of metabolic health (fasting glucose, insulin, leptin, adiponectin, lipids, and c-reactive protein) and b) are impacted by sociodemographic, biological and psychosocial characteristics of mothers at baseline (e.g. age, parity, water/food security, BMI, gestational weight gain, gestational diabetes, depression, perceived stress). Hypothesis: Infant biologic measures of metabolic health will be highly correlated with maternal levels of metabolic health at birth and will vary by maternal baseline characteristics.
Aim 2b. Between delivery and 12 months postpartum, examine how biologic measures of infant metabolic health change in relation to a) maternal biologic measures of metabolic health, b) sociodemographic, biological and psychosocial characteristics of mothers at baseline, and c) maternal/infant behaviors (e.g. responsive feeding practices, infant diet, introduction of sugar-sweetened beverages, early physical activity, etc.). Hypothesis: Biologic measures of infant metabolic health over the first 12 months of life will begin to diverge from maternal levels; and, infant metabolic health between delivery and 12 months postpartum will vary by maternal baseline characteristics and maternal/infant behaviors across study groups.
Aim 2c. Infant metabolic health. Hypothesis: FSN + OSC infants will have better metabolic health (defined by fasting glucose, insulin, leptin, adiponectin, lipid and c-reactive protein levels) at 12 months postpartum compared with IPE + OSC infants.
Secondary Aim 3. To explore how specific community- and tribal level policy, systems, and environmental (PSE) factors affect child feeding practices, healthy weight status, SSB and water consumption, and safe water access on the Navajo Nation.
Aim 3a. Assess the impact of actual and perceived water insecurity on child feeding practices and children's weight and metabolic status. Hypothesis: Participants who do not have or do not trust their household water sources breastfeed less, and feed more SSBs and less water to children, impacting weight and metabolic status at 24 months of life.
Aim 3b. Explore community readiness and political will to address water insecurity among policy, systems, and environmental leaders on the Navajo Nation. Hypothesis: Examination of community- and tribal-level policy, systems, and environmental facilitators and barriers to safe water access will provide key knowledge to promote children's water vs. SSB intake and healthy weight status.
Aim 3c. Compare actual vs. perceived household water safety and determine the distance it takes water insecure households to access safe drinking water. Hypothesis: The distance participants travel to access safe water affects what beverages they feed young children.
Secondary Aim 4. To explore how the COVID-19 pandemic impacted infant/child feeding practices, food and water security, and study participation. Hypothesis: Examination of how the COVID-19 pandemic impacted study outcomes will provide important knowledge about how future home-visiting interventions can best adapt to community-level crises.
The investigators will conduct a randomized 1:1 controlled trial with 338 mothers (ages 14 to 24) and their children (ages 0-24 months) living in the three study sites (2 Navajo; 1 Apache). Assessments in both groups will occur at baseline (\< 32 weeks gestation), 36 weeks gestation, delivery (blood sample collection only), 2 weeks, 2 months, 4 months, 6 months, 9 months, 12 months, 18 months, and 24 months postpartum.
Intervention: The intervention group (n=169) will receive the FSN + OSC. OSC consists of transportation assistance to prenatal and well-baby clinic visits as recommended by the Indian Health Service (IHS) and American Academy of Pediatrics (AAP) and rescue services through linkages to community agencies as needed. The FSN home-visiting module consists of 36 60-minute lessons delivered by trained local FHCs, from 28 weeks gestation to 18 months postpartum. The lessons will be delivered bi-weekly from 28 weeks gestation to birth, weekly from birth to 3 months postpartum, bi-weekly from 3 to 6 months postpartum and monthly from 6 to 18 months postpartum. The lessons focus on three key content domains: 1) promotion of optimal breastfeeding, complementary and responsive feeding across early childhood; 2) promotion of healthy infant/toddler diet and physical activity, as well as reduced screen time and sedentary lifestyle; and 3) promotion of maternal psychosocial well-being, optimization of healthy food/beverage availability and identification/creation of safe play spaces in the home environment.
Comparison Condition: The comparison group will receive IPE + OSC. The IPE home-visiting module consists of 8 30-minute lessons delivered by trained local Family Health Liaisons (FHL), from 28 weeks gestation to 18 months postpartum. The lessons will be delivered at the following assessment time points: 36 weeks gestation, 2 weeks, 2 months, 4 months, 6 months, 9 months, 12 months, and 18 months postpartum. Injury prevention lessons focus on injury prevention topics relevant to the participating communities but that will not overlap in anyway with FSN content, including: motor vehicle safety for mothers and children; preventing scald burns; fire safety; child-proofing a home; preventing falls; preventing poisonings; and preventing animal bites.
OSC transportation visits for both the intervention and comparison groups include transportation for up to 6 prenatal visits from 28 weeks gestation to birth and 8 well-baby visits during the first 18 months of life. OSC was selected because it optimizes the standard of care for young mothers and their children within reservation communities, addresses transportation and access barriers, provides beneficial and ecologically-valid services in the participants' settings, and was previously approved and endorsed by Community Advisory Boards and tribal Institutional Review Boards. By providing OSC to both intervention and control groups, the quality and dose of OSC is controlled so differences between study arms can be validly attributed to the FSN intervention. Two hours is allotted for each OSC visit (for transportation and waiting at clinic visit) x 14 visits = 28 hours of obstetric/pediatric care support. OSC visits will also be used to administer maternal self-reports at relevant time points for both study arms.
Both the intervention and comparison condition participants will receive a follow-up assessment at 24 months, but no education sessions will take place with either study group between 18 and 24 months postpartum.
