Description

Adults with both borderline personality disorder (BPD) and eating disorders (EDs) have been shown to display more severe psychopathology and higher levels of distress as compared to individuals with an ED alone. However, the literature is mixed as to which of the nine BPD symptoms (BPDS) are associated with which ED diagnoses (i.e., anorexia nervosa [AN], bulimia nervosa [BN], and binge eating disorder [BED]). Therefore, the present study aims to examine the association of specific BPDS with ED diagnoses. Data used in the current study were from 36,309 adult participants from the National Epidemiological Survey of Alcohol and Related Conditions-III (NESARC-III), a nationally representative sample of US adults. Logistic regression with complex sampling was used to assess the association of specific BPDS with a lifetime ED diagnosis (AN, BN, or BED) as compared to those who did not have a lifetime ED diagnosis, a psychiatric control group, and a healthy control group. Additional multiple logistic regression models included all BPDS and their association with each ED diagnosis to partition out shared variance explained by each symptom. All BPDS were independently positively associated with increased odds for a lifetime ED diagnosis (AN, BN, or BED) as compared to those who did not have a lifetime ED diagnosis. When accounting for all BPDS, impulsivity (OR = 2.25 [95% CI: 1.44, 3.50], p < .001) and affect instability (OR = 2.48 [95% CI: 1.42, 4.32], p = .002) remained positively associated with BED, and self-injurious behaviors (OR = 2.88 [95% CI: 1.51, 5.50], p = .002) remained positively associated with AN as compared to those who did not have a lifetime ED diagnosis. These associations remained statistically significant when ED diagnoses were separately compared to both a psychiatric and a healthy control group. The current study suggests that certain BPDS are more likely to co-occur with each ED diagnosis. Since EDs and BPD are common comorbidities, further understanding the associations between individual BPDS and each ED diagnosis could guide future research and treating symptoms that are relevant for specific BPD-ED presentations to improve outcomes for these patients.