Cognitive functioning of patients with a PRL-secreting pituitary adenoma: A preliminary report

The aim of this study was to evaluate cognitive functions in patients with prolactin (PRL)-secreting pituitary adenoma.

We conducted a hospital-based case-control study. The effect of PRL overproduction on cognitive processes was assessed with a comprehensive battery of neuropsychological tests to measure verbal memory, nonverbal memory, attention, visuospatial skills, verbal fluency, and executive functions. The data were gathered from 40 participants matched for age, sex, handedness, and education (20 with pituitary adenoma, 20 healthy controls). The patients were examined on the first day of their hospitalization in the Department of Neurosurgery of Medical University of Warsaw. MRI as well as blood test of pituitary hormone level and perimetry test of the visual field were conducted.

The group of patients had significantly lower scores on verbal memory, nonverbal memory, and attention tests compared with healthy volunteers. Their results in memory and visuospatial tests were significantly negatively correlated with the level of PRL but there was no marked relationship between cognitive functioning and the size of tumor.

This study demonstrated a significant relationship between PRL overproduction and worsening of cognitive processes, especially in the domains of memory and attention in hospitalized patients with pituitary adenomas. Greater hyperprolactinemia was associated with a larger decrease in cognitive performance. There was no effect of tumor size.