Perception of health and cognitive dysfunction in acromegaly patients

Abstract

As therapeutic options improve for pituitary adenomas, we like to think we are capable of ‘curing’ patients with these diseases. However, in parallel to the availability of instruments to evaluate the patient’s subjective perception of outcome of the disease, evidence is accumulating on residual morbidity despite endocrine control of hormonal dysfunction. Over the last few years, cognitive dysfunction has been identified as one of the most common co-morbidities of pituitary tumours. Why this occurs is still unclear and could be related to neurovascular decline, ageing, suffering a chronic disease, apart from hormone imbalance, either chronic hormone excess or deficiency (mainly GH or cortisol). Evaluation of cognitive dysfunction in acromegaly has revealed contradictory findings. While Tiemensma et al. [1] reported normal cognitive function in patients with long-term cured acromegaly, several other studies showed deficits in attention, executive functions and memory [2– 4]. In their paper, Yedinak and Fleseriu [5] show cognitive dysfunction in 10 patients with active acromegaly, 17 with controlled acromegaly (defined as normal IGF-I and GH after an oral glucose tolerance test of \1 ng/mL) and 14 non-functioning pituitary microadenoma (NFPA), which were prospectively enrolled over a 3 year period in a tertiary referral centre in the US. They evaluated selfperception of cognitive deficits and quality of life/health by selecting and modifying relevant questions of questionnaires, originally designed for other diseases. Certain questions (16 of the original 37) from the Functional Assessment of Cancer Therapy Cognitive Scale (FACTCog) were selected, which reflected subsets of cognition, like ability to learn, concentration and distractibility, mental agility, memory and recall and verbal recall. Additionally, patients were asked to rate on a 1–5 scale how their health compared today with their desired health and to 12 months before. These questions are focused on patient perception, not objective cognitive measures, and this self-perception of cognitive function is influenced by the patient’s goals, expectations, standards, concerns, personality, as well as life events. For example, increased psychopathology (mainly anxiety and depression), maladaptive personality traits or less effective coping strategies, all previously described in patients with controlled acromegaly, may determine how these questions are answered [1, 6, 7]. The main findings of Yedinak and Fleseriu were that prevalence of cognitive dysfunction, in parallel to severity score for each of the 5 subsets of questions, was higher in NFPA (69 %) than in both groups of acromegalic patients, with no difference in prevalence between the latter (54 % in controlled vs. 57 % in active acromegaly). When the five specific cognitive areas were analysed, significant differences were observed for each subset; NFPA expressed greater cognitive dysfunction for mental agility, memory/ recall and verbal recall, but for ability to learn and concentration/distractibility, the group with active acromegaly expressed more problems and more severe dysfunction. This result is in line with previous studies that have reported attention and memory problems, and attenuation of electrophysiological brain activity in naive acromegaly I. Crespo S. M. Webb Endocrinology/Medicine Departments, Hospital Sant Pau, Centro de Investigacion Biomedica en Red de Enfermedades Raras (CIBER-ER, Unidad 747), ISCIII, IIB-Sant Pau, Pare Claret 167, 08025 Barcelona, Spain