Obsessive-compulsive disorder with comorbid psychiatric disorders

Appropriate management of AN also requires the early detection and treatment of any comorbid psychiatric disorders. The most common comorbid conditions associated with AN are major depressive disorder (MDD), obsessive-compulsive disorder (OCD), and substance use disorders. At the time of presentation, over 50% of AN patients also fulfill criteria for MDD however, accurate diagnosis of depression in these patients is complicated by the fact that prolonged starvation often produces a mood disturbance and neurovegetative symptoms identical to MDD. If MDD appears to be comorbid with AN at the time of presentation, there is debate as to whether it is more prudent to withhold treatment of the depression until weight restoration has been initiated. If the depression persists despite refeeding, then treatment of the depression is likely warranted. 

Psychiatric comorbidity is common, as up to 75% of patients have a primary mood disorder. A link between AN and anxiety disorders, especially social phobia (fear of eating in public) and obsessive-compulsive disorder, has been noted. The lifetime prevalence of obsessive-compulsive disorder in patients with AN is reported to be as high as 25%, much higher than the lifetime prevalence in the general population (2.5%). Personality disorders are also more common among people with AN, especially the avoidant and obsessive-compulsive types, than in the general population. ... 

Paroxetine. Paroxetine, also a serotonin reuptake inhibitor, has been the subject of a case report in two subjects. Ringold [1994] reported the effective treatment of two individuals who had not responded to prior therapy with fluoxetine and sertraline. Both individuals had comorbid psychiatric problems. Subject A demonstrated both social phobia and dysthymia. Although her symptoms of dysthymia were clinically responsive to fluoxetine therapy, her social phobia symptoms were resistant. Subject B had body dysmorphic disorder, obsessive-compulsive disorder, and social phobia. His obsessive-compulsive disorder symptoms benefited from fluoxetine therapy, but his social anxiety was resistant. Sertraline therapy was attempted in both subjects. Subject A required discontinuation because of adverse effects. Subject B experienced a worsening of both obsessive-compulsive disorder and social phobia symptoms. Both subjects demonstrated a positive response in their symptoms when switched to paroxetine [20 mg/day]. 

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