Economic resources have been inversely associated with risk of childhood overweight/obesity. Few studies have evaluated whether this association is a direct effect of economic resources or is attributable to unmeasured confounding or reverse causation. American Indian–owned casinos have resulted in increased economic resources for some tribes and provide an opportunity to test whether these resources are associated with overweight/obesity.
To assess whether openings or expansions of American Indian–owned casinos were associated with childhood overweight/obesity risk.
Design, Setting, and Participants
We used repeated cross-sectional anthropometric measurements from fitness testing of American Indian children (aged 7-18 years) from 117 school districts that encompassed tribal lands in California between 2001 and 2012. Children in school districts encompassing American Indian tribal lands that either gained or expanded a casino were compared with children in districts with tribal lands that did not gain or expand a casino.
Main Outcomes and Measures
Per capita annual income, median annual household income, percentage of population in poverty, total population, child overweight/obesity (body mass index [BMI] ≥85th age- and sex-specific percentile) and BMI z score.
Of the 117 school districts, 57 gained or expanded a casino, 24 had a preexisting casino but did not expand, and 36 never had a casino. The mean slots per capita was 7 (SD, 12) and the median was 3 (interquartile range [IQR], 0.3-8). Among districts where a casino opened or expanded, the mean change in slots per capita was 13 (SD, 19) and the median was 3 (IQR, 1-11). Forty-eight percent of the anthropometric measurements were classified as overweight/obese (11 048/22 863). Every casino slot machine per capita gained was associated with an increase in per capita annual income (β = $541; 95% CI, $245-$836) and a decrease in percentage in poverty (β = −0.6%; 95% CI, −1.1% to −0.20%) among American Indians living on tribal lands. Among American Indian children, every slot machine per capita gained was associated with a decreased probability of overweight/obesity by 0.19 percentage points (95% CI, −0.26 to −0.11 percentage points) and a decrease in BMI z score (β = −0.003; 95% CI, −0.005 to −0.0002).
Conclusions and Relevance
In this study, opening or expanding a casino was associated with increased economic resources and decreased risk of childhood overweight/obesity. Given the limitations of an ecological study, further research is needed to better understand the mechanisms behind this association.