Alcohol and Binge Eating as Mediators between Post-traumatic Stress Disorder Symptom Severity and Body Mass Index

OBJECTIVE: Sexual minority women are at elevated risk for obesity, as well as of exposure to traumatic events. Rates of obesity are elevated in individuals with PTSD, but we know little about why this relationship exists. Behavioral mechanisms, such as eating patterns and alcohol use, are possible explanations that would be clinically useful to identify. METHODS: We longitudinally investigated binge eating and alcohol use as mediators of the relationship between PTSD symptom severity and body mass index (BMI) in a large sample of young adult sexual minority women (N = 425). We assessed PTSD symptom severity at baseline, binge eating and alcohol use 12-months later, and BMI 24-months after baseline. RESULTS: Using a multiple mediator model, we found that higher baseline PTSD symptom severity was significantly associated with higher BMI 2 years later, operating through binge eating behavior, but not through alcohol use. Exploratory moderator analyses found that this effect was higher for those with lower baseline BMI. CONCLUSIONS: Results suggest that higher PTSD symptoms are longitudinally associated with increased BMI, and that binge eating behavior is one factor that explains this relationship.