Smaller Pituitary Volumes in Patients with Delusional Disorder

Delusional disorder shares some clinical characteristics of OCD and hypochondriasis. Delusions compared to obsessions in the OCD and compared to bodily preoccupations in the hypochondriasis are more established beliefs.

To measure pituitary volumes in patients with delusional disorder and hypothesized that volumes would be reduced in those patients by a mechanism that we could not account for before for patients with OCD and hypochondriasis.

Eighteen patients with delusional disorder and healthy controls were included into the study. Pituitary gland volumes were measured.

When using independent t test, the mean total pituitary volume was 777.22±241.28 mm³ in healthy controls, while it was 532.11±125.65 mm³ in patients with delusional disorder. The differences in regard to pituitary gland volumes between patients with delusional disorder and healthy control subjects were statistically meaningful (p<0.01), as supported by ANCOVA, with the covariates of age, gender and total brain volumes as covariates.

We determined that patients with delusional disorder had smaller pituitary volumes compared to those of healthy control subjects.