A randomized controlled trial of culturally tailored dance and reducing screen time to prevent weight gain in low-income African American girls: Stanford GEMS

Abstract

Objective: To test a 2-year community- and family-based obesity prevention program for low-income African American girls: Stanford GEMS (Girls' health Enrichment Multi-site Studies).

Design: Randomized controlled trial with follow-up measures scheduled at 6, 12, 18, and 24 months.

Setting: Low-income areas of Oakland, California.

Participants: African American girls aged 8 to 10 years (N=261) and their parents or guardians.

Interventions: Families were randomized to one of two 2-year, culturally tailored interventions: (1) after-school hip-hop, African, and step dance classes and a home/family-based intervention to reduce screen media use or (2) information-based health education.

Main outcome measure: Changes in body mass index (BMI).

Results: Changes in BMI did not differ between groups (adjusted mean difference [95% confidence interval] = 0.04 [-0.18 to 0.27] per year). Among secondary outcomes, fasting total cholesterol level (adjusted mean difference, -3.49 [95% confidence interval, -5.28 to -1.70] mg/dL per year), low-density lipoprotein cholesterol level (-3.02 [-4.74 to -1.31] mg/dL per year), incidence of hyperinsulinemia (relative risk, 0.35 [0.13 to 0.93]), and depressive symptoms (-0.21 [-0.42 to -0.001] per year) decreased more among girls in the dance and screen time reduction intervention. In exploratory moderator analysis, the dance and screen time reduction intervention slowed BMI gain more than health education among girls who watched more television at baseline (P = .02) and/or those whose parents or guardians were unmarried (P = .01).

Conclusions: A culturally tailored after-school dance and screen time reduction intervention for low-income, preadolescent African American girls did not significantly reduce BMI gain compared with health education but did produce potentially clinically important reductions in lipid levels, hyperinsulinemia, and depressive symptoms. There was also evidence for greater effectiveness in high-risk subgroups of girls.

Trial registration: ClinicalTrials.gov NCT00000615.

Figure 1. Participant Recruitment and Enrollment Flow Chart

261 families/households with 284 eligible girls were recruited, enrolled and randomized in the trial from October 2002 thru February 2004. In families/households with more than one eligible girl, one girl was randomly chosen for the analysis sample of 261 girls. The only statistically significant difference in follow-up rates between groups was at FU3 (P=.005). Sixteen (11.9%), 27 (20.2%), 51 (38.1%), and 32 (23.9%) Treatment group girls and 15 (11.8%), 14 (11.0%), 39 (30.7%), and 49 (38.6%) Comparison group girls completed a total of 1, 2, 3 or all 4 of the follow-up visits (P = .053). Personnel difficulties with data collectors resulted in larger rates of missing data at FU2 and FU3.

Figure 2. Dance Class Attendance Rates by Time Period

Attendance dropped substantially over the course of the study. Box-and-whisker plots of the girls’ mean percent attendance of all possible dance classes during their first, second, third and fourth six months of participation in the study. Means are indicated by the point, medians are the central horizontal line, the box defines the 25^th and 75^th percentiles, and whiskers indicate 1.5 interquartile ranges beyond the 25^th and 75^th percentiles. In the third and fourth six month intervals, the median and 25^th percentile overlap with a value of 0.

Figure 3

Fasting Insulin Sample Distributions by Intervention Group at Baseline and Follow-Up. Percent of the dance and screen time reduction sample (baseline thin solid line, follow-up thick solid line) and the health education sample (baseline thin dashed line, follow-up thick dashed line) with fasting insulin above the corresponding threshold level on the horizontal axis (in uIU/ml). As shown, the distribution of fasting insulin levels shifted to the right (greater fasting insulin levels) among girls in the health education group compared to the girls in the dance and screen time reduction group, from baseline to FU4.

Figure 4. Baseline Parent/Guardian Marital Status and Girl’s TV Viewing Time as Moderators of Intervention Effects on Body Mass Index

In the exploratory moderator analysis, the dance and screen time reduction intervention was significantly more effective than health education among those girls with an unmarried parent/guardian and among those who watched more than the mean amount of television at baseline. The figure illustrates the differences between the intervention groups in the mean ± se changes in BMI for the subgroup of girls with an unmarried parent/guardian, girls who watched greater than the mean of baseline television viewing, and girls with both an unmarried parent/guardian and high baseline television watching.