Predictors and Outcomes of Pica
Pica is an eating disorder of chewing non-nutritional substances such as ice, dirt, corn starch, paint etc. for more than one month, as diagnosed based on DSM-V criteria. Pagophagia (consumption of ice) is the predominant type of pica in adults and geophagia (consumption of dirt) is most common in children. Pica is poorly understood, but its association with iron deficiency is well established. The purpose of this study is to identify predictors of pica including iron deficiency, other comorbid conditions, psychiatric disorders, behaviors and laboratory markers in children and adults. We also studied health outcomes of pica including but not limited to hospitalizations in children and adults. This is a case-control study of 7,684 patients aged 2 to 64 years who were enrolled in one of the nation’s largest commercial insurance programs between January 1, 2008, and December 31, 2014. Cases were defined as patients who had a diagnosis of pica listed on either inpatient or outpatient claims. Cases were matched with 3 controls based on diagnosis or index date (month and year), age, gender, and region. The predictors of pica were identified in the 12 month look-back period before diagnosis or index date. Cases and controls were also followed for 12 months after diagnosis or index date to study outcomes. The findings of this study suggest that iron deficiency, mood disorders and obesity were significant predictors of pica. In children, autism spectrum disorder (ASD) was the strongest predictor of pica. In adults, additional predictors were anxiety disorder and menstrual bleeding disorders. We also found that decreased hemoglobin and increased red cell distribution width (RDW) were laboratory predictors of pica. Our study identified important outcomes of pica including hospitalization in the first 75 days after diagnosis, gastrointestinal (GI) disorders and infections, and fluid and electrolyte imbalance in both children and adults. Moreover, our findings suggest that lead poisoning was a significant outcome of pica in children. Another major finding of this study was that other eating disorders co-exist with pica in children and adults. These findings enhance our understanding of pica in children and adults.