Rigid Minds: The Role of Obsessive-Compulsive Personality Traits in Anorexia Nervosa.

Objective: Restrictive eating behavior in anorexia nervosa (AN) is often characterized by rigidity, dichotomous thinking, and cognitive inflexibility. These traits are also central to obsessive-compulsive personality disorder (OCPD). The current study assessed whether OCPD traits among patients with AN were associated with the severity of illness or short-term treatment outcome.

Method: Presence of OCPD traits were measured among hospitalized adults and adolescents as well as healthy peers (HC), using the Pathological Obsessive Compulsive Personality Scale (POPS). In addition to comparing groups, patients with AN were assessed before and after weight restoration treatment to examine changes with renourishment. Associations between POPS and other indices of clinical severity were tested.

Results: POPS scores were significantly higher among AN (n = 208) than HC (n = 124) (Total: 173.2 ± 33.4 vs. 132.3 ± 32.6, t₃₃₀ = 10.9, p < 0.001), across all five domains (Rigidity, Emotional Overcontrol, Maladaptive Perfectionism, Reluctance to Delegate, Difficulty with Change). Among AN, higher POPS scores were positively associated with EDE-Q (r₁₉₅ = 0.29, p = < 0.001) and YBC-EDS scores (r₂₀₁ = 0.28, p = < 0.001). POPS scores did not change with weight restoration and were not significantly associated with treatment outcome.

Discussion: OCPD personality traits were elevated among individuals with AN, though scores were lower than populations with OCPD. These traits did relate to illness severity, but not to treatment outcome. While these traits may merit attention in treatment, co-occurring OCPD may not be central to the kind of rigidity that perpetuates AN.