Reducing pediatric caries and obesity risk in South Asian immigrants: randomized controlled trial of common health/risk factor approach

Maternal feeding practices in early life increase the risk of caries (i.e., cariogenic) and obesity (i.e., obesogenic). They include: prolonged use of bottles (and ‘sippy cups’); adding solids and sweets to bottles; nighttime feeding; salty and starchy snacks; sweets, and sweetened beverages. Bottle use beyond 12–15 months increases risk for both conditions [20‐26], as do bottles at night or naptime [22] or bottles that contain solids [27] and sweeteners [28]. Bottle feeding facilitates overriding of a child’s internal satiety cues, [29] thereby reducing ability to self-regulate intake [30]. This may further promote both weight gain [31, 32] and early childhood caries (ECC) [24].

Such feeding practices are common in SA communities [33, 34]. Up to 75% of low-income SA 15-month olds still use a bottle, and 30% regularly drink sweetened milk [35‐37]. Non-responsive feeding is also common in SA families. Non-responsive feeding’s defining feature is caregiver lack of responsiveness to a child’s feeding cues. It includes both adult controlling (forcing or restricting) and child controlling (indulgent) feeding [38]. Forcing/controlling feeding leads to rapid weight gain in the first year of life, which predispose to overweight in later years [39, 40]. Indulgent styles are associated with obesity in toddlers and older children [41]. Among SAs in the New York area, ‘force feeding’ is routine. Once children are old enough to ask for food, force-feeding yields to indulgent feeding. SA mothers fear distressing their children by refusing food [42].

In addition to common risk behaviors, there are unique risk behaviors associated with obesity and caries that are common among SA immigrants. SA children are more sedentary than their white counterparts, raising their risk of obesity [43‐46]. Oral health prevention—e.g., brushing, oral hygiene, and preventive dental care—are undervalued in SA communities. Many families seek dental care only when there is pain or visible decay; baby teeth may be viewed as dispensable [42, 47, 48].

SA married women’s low status and limited access to family decision-making may impede adherence to medical advice [42]. Senior family members may insist traditional feeding patterns including frequent sweets and delayed weaning [37, 42]. Maternal depression—due to factors such as poverty, isolation, and marital abuse—is common in SA families [49‐51]. Maternal depression is associated with non-responsive feeding [52, 53] and child obesity [41]. Poverty and its sequelae, including substandard housing, further limit mothers’ ability to change feeding patterns. Such may cause disruption and crying, which may be difficult to tolerate in crowded living quarters [42].

Like other low-income immigrants, SA children lack access to dental care [4, 54, 55]. Pediatricians rarely refer to dentists [4, 54‐57]. Guidelines recommend a first dental visit by 12 months of age and two visits per year for low-income and immigrant children [58, 59]. Yet only 1.5% of one-year olds visit a dentist each year [60] and rates are lowest in poor families who could most benefit [61]. Another barrier to care for low income children is the fact that many dentists on the US don’t accept Medicaid or Children’s Health Insurance Program coverage [62].

These include cultural beliefs and practices, along with low awareness of risk factors. Though concerns over child feeding are widely shared among SA mothers, there is relatively little understanding of how non-responsive feeding leads to child food refusal, creating a vicious cycle of increased maternal anxiety and force feeding. One SA mother on www.​indusladies.​com, a website for South Asian moms, asks: "Why do American kids happily feed themselves from the age of one year old and are constantly asking for food? Why do Indian kids hate food and need to be FORCE FED until the age of 4,5,6, or even 7?" Pediatricians in the SA community often report frustration. “Feeding problems take up 75% of my time.” (Mehotra N, SAPPHIRE network pediatrician. In.; 2015, personal communication). Physicians lack tools and support needed to address this problem. “The most commonly prescribed medication in my practice is an appetite stimulant. Even though the child doesn’t need it, I have to prescribe to get peace in the family.” (Mehotra N. In.; 2015, personal communication).

The Knowledge Translation campaign will work with private practitioners, residents, and teaching faculty in dental and pediatric departments. Through dialogue and presentations in clinical and educational settings, the goal is to develop new best practices and guidelines regarding the improved care of South Asian immigrant children.

The randomized controlled trial (RCT), CHALO! will answer the following research questions: a) Does a culturally-tailored CR/HFA home-visiting intervention, from child age 6 through 16 months, reduce cariogenic and obesogenic behaviors in SA immigrant families (primary hypothesis)? b) Is this CR/HFA intervention associated with reduced incidence of oral caries and obesity at 18 months of age (secondary hypothesis)?

An EUC counseling intervention will be delivered immediately following the T0 Baseline Interview, just prior to randomization. EUC Components include: 1) a pamphlet- containing basic ECC and Obesity prevention messages, and 2) Dental Referrals. We developed a Screened Dental Provider list of dentists who: a) are willing to see 12 month old children; and b) accept most insurance plans in the study practices.

Mother-only visits will focus on building rapport and intimacy, identifying family/household concerns, reviewing risk/health behaviors, reviewing, setting, and troubleshooting goals, building skills through active interaction with the child, and providing education. Messages will be provided orally and via culturally tailored, attractive educational materials. To bolster mothers’ skills, CHW-guided interactions with the dyads will include: recognizing infant satiety and hunger cues via responsive bottle feeding, preparing age-appropriate self-feeding foods, encouraging tummy time and active play, transitioning from naptime milk to water bottles, and oral hygiene practices such as tooth brushing. At each visit, the CHW encourages the mother to set a concrete, manageable behavior change goal. Patient navigation, as needed, will encourage mothers to make and keep two dental visits for their child, over the 12 month follow-up. Family visits will, similarly, assess family views on barriers to change, and enlist support for mothers’ child feeding goals (Fig. 1).

We will use MySmileBuddy (MSB), an iPad based ECC risk assessment and educational tool [66]. MSB was validated in previous research [67]. The MSB guides parents through a modified 24-h dietary recall for their child. We have adapted the MSB to reflect culturally appropriate SA foods and beverages, as well as the types of bottles and cups used for beverages. Participants are cued by queries (e.g., first thing to eat or drink upon waking) and attractive color photographs of food and beverage groupings. Prior to administration, the research assistant will ask whether the prior 24 h represented a ‘usual day.’ If not, participants will conduct a recall for one day earlier. We will conduct a second 24-h recall for a subset of participants.

Unique risk factors for obesity (sedentary behavior/screen time) will be assessed through previously validated questionnaire items used in other large studies. Unique ECC-risk factors include dental visits and oral hygiene practices. We will assess frequency of tooth brushing, use of toothpaste, and use of tap water using items from a measure developed by the CDC. Dental health utilization will be assessed through questions at T1 and T2.

The RCT’s secondary aim is to reduce the velocity of weight gain in months 12–18, and the incidence of oral caries at 18 months. Weight and length data will be collected by research assistants at the T0, T1, and T2 outcomes assessments. Study pediatricians will train research staff in anthropometrics protocol. For length, two supine measures will be taken using infantometers (Seca 417, Brooklyn NY), to the nearest 0.1 cm. For weight, children will be measured with diaper and light clothing. ECC will be assessed by study staff using Intraoral cameras at the 18 month follow-up. Intraoral cameras are valid [68‐72] and acceptable [73] in young children. Images will be transmitted to pediatric dentists at the Kodiak who will determine the presence of visible dental caries and (if any) their severity (Table 3).

Home visiting interventions involve three components: Dose (timing/length of visits); Content (degree to which it was delivered); and Rapport (quality of visitor-participant relationship) [74]. To assess Dose and Content, we will adapt a home visit form used in large home visiting studies, for CHALO [75] (see Additional file 1: Figure S1) to be completed after each visit. To assess relationship warmth and rapport, both CHWs and mothers will complete the Working Alliance Questionnaire [76] adapted for the study.

Practices will generate quarterly lists of 2–5 month olds seen for well-child visits. Parents will receive an “opt-out” letter from the pediatrician when their child is 4–5 months old, with a number to call to decline study contact. Parents who do not decline will be contacted by study staff to arrange a Baseline (T0) interview. We will set individual practice target recruitment rates based on target population size at each practice. Strategies to promote retention include: gift card incentives for research interviews, quarterly post-card reminders and incentives to notify study of address or name changes, holiday greeting postcards, and reminders for upcoming interviews.

Participants will be randomized 1:1 to the intervention or EUC control group, after providing informed consent (see below). Following delivery of the EUC at the T0 (baseline) assessment, the CHW will randomize participants by opening a sealed envelope containing the random assignment (prepared in advance by the project statistician). This sequence preserves masking of outcomes assessment at the T0 interview. Neither the outcomes section of the study database, nor written study materials will include a group identifier, though participants may indicate group assignment to research assistants at the12-month (T1) and 18-month (T2) follow-ups.

This study was approved by the Albert Einstein college of Medicine’s Committee on Clinical Investigation. Bi-lingual research assistants will consent mothers in their home prior to the baseline (T0) interview.

Based on preliminary studies, we estimate a between group difference in decline in the number of daily bottles and sippy cups (combined) of 0.7. This equates to a small-moderate standardized effect size (Cohen’s d) of 0.7/2 = 0.35. With n = 300 participants (150 per am) the trial will have greater than 85% power to detect an effect size of 0.35 (two-tailed alpha = 0.05). To account for a 20% attrition rate, we will enroll 360 subjects (180 per arm).

Analysis plan: Analyses will be intent-to-treat. Generalized linear mixed models (GLMM) will be employed to analyze primary CRFA outcomes, as well as unique obesogenic and cariogenic outcomes. To test the impact of the intervention on secondary outcomes-- caries, weight for length, velocity of weight gain-- similar GLMM models will be fit. Individuals lost to follow-up at T1 or T2 will remain in the analytic sample. Further details are provided below.

The trial’s primary outcome is frequency of combined sippy cup and bottle use (count/day). The intervention’s effectiveness will be tested by a random-effects Poisson regression model, with the count of bottle/sippy cup as dependent variable, an indicator for study arm, a time indicator and their interaction term as fixed effects, and a random intercept at the person level. We will adjust for child age, given shifts in feeding behavior at this age. If the mean (sd) of the outcome demonstrates over -dispersion relative to a Poisson model, we will use negative binomial regression instead. We will report the coefficient of the interaction term, which estimates the rate ratio in bottle/sippy cup use attributable to the intervention, and its 95% confidence interval. To test the null hypothesis, we will use a z-test.

To test the impact of the intervention on secondary outcomes (behavioral), we will use random-effect generalized linear regression models. The intervention’s impact will be assessed by the coefficient of the interaction term. The estimate and its 95% confidence interval will be reported. For secondary caries, weight for length, and velocity of weight gain outcomes, logistic regression or a linear regression model will be applied as appropriate. Anthropometrics: We will use WHO growth standards [77] to calculate BMI-for-age Z scores --weight/length² (kg/m²), standardized for sex and actual age at measurement. We will categorize children as “overweight” and “obese” if their BMI-for-age Z-scores exceed + 2 and + 3, respectively, as recommended by the WHO [78], and Weight velocity Z scores: for each 6 month period: 6 m. > 12 m. 12 m. > 18 m.

Missing data will arise from both non-response and study attrition. Random bias created by missing items will be addressed by using multiple imputations [79]. These will use chained equations incorporating baseline and end-of-study data and behavioral variables. For non-random bias, sensitivity analyses will be used to impute best and worst-case credible values for missing variables and then apply the original analyses to these supplemented data sets.

We will use REDCap (Research Electronic Data Capture) software for database development, data entry, coding and secure data storage [80]. Research assistants can access REDCap both onsite and in the field, and enter data directly as it is collected. The team will use REDCap features to manage follow-up reminders, and adherence to T1 and T2 windows for interview completion. All data will be maintained in secure files during and after the trial.