Do Personality Disorders Increase Obesity Risk?

Weight loss programs should attend to the special needs of patients with comorbid personality disorders (PDs), according to a new systematic review by Gerlach et al published in the May 2016 issue of World Obesity.

The researchers, who are affiliated with 2 German universities, evaluated the results of 68 studies that investigated the association between PDs and overweight/obesity. Additional areas of focus were the predictive value of PDs for the development of obesity and the effectiveness of weight reduction treatments in this population.

The review encompassed studies spanning the time period of 1980 — when PDs were introduced as diagnostic categories into the Diagnostic and Statistical Manual of Mental Disorders (DSM)-III-R — through June 2015, with studies that used the current DSM-5 definition of PDs. The review focused only on studies specifically investigating PDs, rather than studies that included PD-like personality traits and styles, irrespective of normal or psychopathologic status.

The researchers found that adults with any PD have a higher risk of obesity. Among women in particular, the researchers found an association between avoidant or antisocial PD and severe obesity. Women with paranoid or schizotypal PD were likewise at higher risk for obesity.

Clinical studies of obesity demonstrated a high comorbidity of PDs with binge-eating disorder (BED). For this reason, BED is of “special interest,” as it is characterized by greater impulsivity and comorbid psychopathology. Studies differentiating obese individuals with and without BED found BED to be associated with higher prevalence rates of borderline, avoidance, histrionic, obsessive-compulsive, and dependent PD, especially in women.

Patients of both genders with PDs showed less treatment success in conservative weight-loss treatment programs for obesity than did patients without any PD.

“The epidemiological importance of PDs in obesity is underlined by population-based cross-sectional analyses,” the researchers observed. While the prevalence of PDs in the general population is estimated at 11.4% to 14.7%, “an increasing degree of severity of obesity is accompanied by a rising prevalence of PDs, reaching 23.4% for obesity class III.”

They noted that the majority of studies showed comorbidity of Cluster C PDs with obesity, with a dominance of obsessive-compulsive PD in both genders. This association might be “mediated by depression,” they suggested.

The researchers concluded that there are important clinical implications of their study. “A diagnostic clarification, at least within a screening examination, would appear to be useful with regard to obesity treatment,” including “typical aspects of the patients’ experiences and behaviours that might negatively influence the course of weight reduction treatments” and could be addressed by behavioral therapy interventions.

Reference

Gerlach G, Loeber S, Herpertz S. Personality disorders and obesity: a systematic review. Obes Rev. 2016 May 27. DOI: 10.1111/obr.12415.