Cognitive functioning in patients treated for nonfunctioning pituitary macroadenoma and the effects of pituitary radiotherapy

Context and objective

Cognitive deterioration is reported in patients with a nonfunctioning pituitary macroadenoma (NFA) and after pituitary radiotherapy. However, reported results are inconsistent and are potentially confounded by different underlying pituitary disorders. The aim of this study was to examine cognitive functions in patients previously treated for NFA with or without radiotherapy.

Design

Verbal memory was assessed with the Dutch equivalent to the Rey Auditory Verbal Learning Test (15 Words Test, 15 WT). Executive functioning was examined using the Ruff Figural Fluency Test (RFFT). We compared our patient cohort with large reference populations representative of the Dutch population.

Patients

Eighty-four patients (62 +/- 10 years) who underwent transsphenoidal surgery 8.6 +/- 6.3 years earlier participated. Patients who underwent radiotherapy (n = 39) were compared to those who received surgery alone (n = 45). All patients were on stable hormonal replacement therapy.

Results

The total patient group scored significantly below the reference sample on all 15 WT z-scores (95%CI): short-term memory, -0.3 (-0.5 to -0.1); total memory, -0.8 (-1.1 to -0.5); learning score, -0.3 (-0.5 to -0.1); delayed memory, -0.8 (-1.1 to -0.5), all P <0.01. The total patient group scored significantly below the reference sample on RFFT z-scores (95%CI): unique designs, -0.7 (-0.9 to -0.5) and perseverative errors, -0.5 (-0.8 to -0.2), both P <0.001. Patients who underwent radiotherapy showed no significant differences on cognition when compared to those who received surgery alone.

Conclusion

Patients with NFA score significantly worse on cognition compared to reference populations. Radiotherapy does not appear to have a major influence on cognition.