Serum prolactin levels in manic patients

Decreased pituitary volume in patients with bipolar disorder

BACKGROUND

Neuroendocrinologic investigations in bipolar disorder have suggested abnormalities in pituitary function. However, few imaging studies have evaluated possible anatomical differences in this brain structure in mood disorder patients. Our aim was to examine potential abnormalities in pituitary volume in patients with bipolar and in a comparison group of patients with unipolar disorder.

METHODS

We measured the volumes of the pituitary gland in 23 patients with bipolar disorder (mean +/- s.d. = 34.3 +/- 9.9 years) and 13 patients with unipolar disorder (41.2 +/- 9.6 years), and 34 healthy control subjects (36.6 +/- 9.6 years) using 1.5 mm thick T1-weighted coronal 1.5 T MRI images. All measurements were done blindly by a trained rater.

RESULTS

Patients with bipolar disorder had significantly smaller pituitary volumes than healthy control subjects (mean volume +/- s.d. = 0.55 +/- 0.15 ml and 0.68 +/- 0.20 ml, respectively; ANCOVA, F = 8.66, p = 0.005), and than patients with unipolar disorder (0.70 +/- 0.12 ml, F = 5.98, p = 0.02). No differences were found between patients with unipolar disorder and healthy control subjects (F = 0.01, p = 0.91).

CONCLUSIONS

To our knowledge, this is the first study that reports smaller pituitary volumes in bipolar disorder. Our findings suggest that detectable abnormalities in pituitary size are present in patients with bipolar disorder, which may reflect a dysfunctional HPA axis.

A study of serum prolactin levels in schizophrenia: comparison of males and females

1. Serum prolactin levels were measured in large cohorts of schizophrenic patients (67 males and 42 females) and normal subjects (78 males and 42 females). 2. There was no significant differences between the serum prolactin levels of patients and controls, except in the age group 15-29 years. There were no significant differences between the serum prolactin levels of males and females, either among the patients or the control subjects. 3. The rise in serum prolactin levels after the commencement of neuroleptic medication in the patients was greater in females than in males even though the female patients received neuroleptics at lower doses. 4. These data indicate that serum prolactin levels in unmedicated males and females are similar; however, the prolactin response to neuroleptic medication is greater in females than in males.