Physical Consequences of Eating Disorders
For many studies of biological differences between individuals with eating disorders and healthy individuals, it is not possible to determine whether the difference predated the presence of the eating disorder or is a consequence of the eating disorder. When the body has inadequate resources to maintain body weight and must revert to using its fat stores, other physical changes necessarily follow. This section discusses known physical consequences of eating disorders. As discussed below, some consequences may contribute to eating disorder maintenance. As a preview of this section, Table 8.2 shows the medical complications frequently associated with eating disorders organized by whether they are attributed consequences of starvation, binge eating, or purging.
Consequences of Starvation
Neuroanatomical Changes
Patients with AN have larger cerebral ventricles than healthy controls do (D. K. Katzman, Zipursky, Lambe, & Mikulis, 1997; Kingston, Szmukler, Andrewes, Tress, & Desmond, 1996; Krieg et al., 1989; Roberto et al., 2011; Swayze et al., 1996). Ventricles contain cerebrospinal fluid, and increases in ventricle size reflect decreases in brain mass (loss of gray and white matter). Thus this finding indicates that in addition to causing breakdown of fat, muscle, and bone (see Table 8.1), starvation triggers the breakdown of brain matter. Some of the lost brain matter is regained with recovery (Kingston et al., 1996; Roberto et al., 2011; Swayze et al., 1996). However, evidence of diminished gray matter persists after recovery from AN (Katzman et al., 1997). McCormick et al. (2008) found that the volume of the anterior cingulate cortex was reduced in patients with AN compared with controls, although it increased significantly with inpatient treatment and weight recovery. Smaller increases in anterior cingulate cortex volume prospectively predicted relapse after hospital discharge (McCormick et al., 2008).
