Cognitive performance after postoperative pituitary radiotherapy: a dosimetric study of the hippocampus and the prefrontal cortex

[Prospective longitudinal study on the evolution of autobiographical memory in patients irradiated for benign skull base tumour]

PURPOSE

Cranial irradiation can lead to long-term neurological complications, in particular memory disorders. The aim of this prospective study is to evaluate the impact of irradiation of benign skull base tumours located near the hippocampi on autobiographical memory.

PATIENTS AND METHODS

From 2016 to 2019, patients with cavernous sinus meningioma or pituitary adenoma treated with normofractionated irradiation were included. Patients underwent full neuropsychological assessment at baseline, 1year and 2years post-treatment. Neuropsychological tests were converted to Z-Score for comparability.

RESULTS

Twelve of the 19 patients included had a complete neuropsychological evaluation at 2years and were analysed. On the "TEMPau" test, no significant difference in autobiographical memory was found at 2years, regardless of the period of autobiographical memory. The mean hippocampal dose had no impact on the variation in autobiographical memory. There was no significant cognitive impairment in the other domains assessed, such as attention, anterograde memory, working memory and executive functions. Autobiographical memory was independent of these other cognitive domains, which justifies its specific study.

CONCLUSION

Radiotherapy to the skull base for a benign pathology does not lead to significant cognitive impairment. Longer follow-up would be needed to confirm these results.

Quality of life in Cushing's syndrome

Measurement of Health-Related Quality of Life (HRQoL) is emerging as an important clinical endpoint which complements diagnostic workup and contributes to place patients at the centre of the decision-making process through the recognition of their needs, concerns, goals and expectations. Chronic excessive cortisol exposure in Cushing's syndrome (CS) causes severe physical and psychological morbidity which invariably affects HRQoL during the active phase of the disease and even after successful treatment. This sustained deterioration of patient's wellbeing is partly related to the persistence of several features associated with prior cortisol excess, including affective disorders, cognitive dysfunctions and negative illness perception. The aim of this review is to summarize the most recent evidence on HRQoL in CS, including the main determinants of its impairment and the results of some educational programs specifically addressed to improve patient's coping abilities. The preliminary results of an unpublished survey on patient's unmet needs will also be presented.

Diffusion tensor imaging indices to predict cognitive changes following adult radiotherapy

BACKGROUND

Diffusion tensor imaging (DTI) can detect changes to white matter tracts following assaults including high dose radiation. This study aimed to systematically evaluate DTI indices to predict cognitive changes following adult radiotherapy.

MATERIALS AND METHODS

We searched PubMed and Scopus electronic databases to identify eligible studies according to PRISMA guidelines. Studies were extracted for information on demographics, DTI changes and associations to cognitive outcomes.

RESULTS

Six studies were selected for inclusion with 110 patients (median study size: 20). 5/6 studies found significant cognitive decline and analysed relationships to DTI changes. Decreased fractional anisotropy (FA) was consistently associated with cognitive decline. Associations clustered at specific regions of cingulum and corpus callosum. Only one study conducted multivariable analysis.

CONCLUSION

Fractional anisotropy is a clinically meaningful biomarker for radiotherapy-related cognitive decline. Studies accruing larger patient cohorts are needed to guide therapeutic changes that can abate the decline.

Cognitive functioning in patients with nonfunctioning pituitary adenoma before and after endoscopic endonasal transsphenoidal surgery

OBJECTIVE

Patients with nonfunctioning pituitary adenomas (NFPAs) can suffer from cognitive dysfunction. However, the literature on longitudinal cognitive follow-up of patients undergoing endoscopic endonasal transsphenoidal surgery (EETS) is limited. This study was performed to investigate perioperative cognitive status and course in patients with NFPAs.

METHODS

Patients underwent computerized neuropsychological assessment 1 day before (n = 45) and 3 months after (n = 36) EETS. Performance in 7 domains was measured with a computerized test battery (CNS Vital Signs) and standardized using data from a healthy control group. The authors conducted analyses of cognitive performance at both time points and changes pre- to post-ETSS on a group and an individual level. Linear multiple regression analyses were employed to investigate predictors of cognitive performance.

RESULTS

On average, patients scored significantly lower in 6 of 7 cognitive domains before and after surgery than controls. Impairment proportions were significantly higher among patients (56% before surgery, 63% after surgery) than among controls. Patients showed no change over time in group-level (mean) performance, but 28% of individual patients exhibited cognitive improvement and 28% exhibited cognitive decline after surgery. Hormonal deficiency showed a positive correlation with verbal memory before surgery. Postoperative performances in all cognitive domains were predicted by preoperative performances.

CONCLUSIONS

Cognitive impairment was present before and after EETS in over half of NFPA patients. Individual patients showed diverse postoperative cognitive courses. Monitoring of cognitive functioning in clinical trajectories and further identification of disease-related and psychological predictors of cognition are warranted.

Radiotherapy as a tool for the treatment of Cushing's disease

Treatment of Cushing's disease (CD) is one of the most challenging tasks in endocrinology. The first-line treatment, transsphenoidal pituitary surgery, is associated with a high failure rate and a high prevalence of recurrence. Re-operation is associated with an even higher rate of a failure and recurrence. There are three main second-line treatments for CD - pituitary radiation therapy (RT), bilateral adrenalectomy and chronic cortisol-lowering medical treatment. All these treatments have their limitations. While bilateral adrenalectomy provides permanent cure of the hypercortisolism in all patients, the unavoidable chronic adrenal insufficiency and the risk of development of Nelson syndrome are of concern. Chronic cortisol-lowering medical treatment is not efficient in all patients and side effects are often a limiting factor. RT is efficient for approximately two-thirds of all patients with CD. However, the high prevalence of pituitary insufficiency is of concern as well as potential optic nerve damage, development of cerebrovascular disease and secondary brain tumours. Thus, when it comes to decide appropriate treatment for patients with CD, who have either failed to achieve remission with pituitary surgery, or patients with recurrence, the pros and cons of all second-line treatment options must be considered.

Long-term cognitive dysfunction after radiation therapy for primary brain tumors

Background: The extent of radiation therapy (RT)-induced changes in cognitive function is unknown. RT with protons instead of photons spares the healthy brain tissue more and is believed to reduce the risk of cognitive dysfunction. There is modest knowledge on which parts of the brain we need to spare, to prevent cognitive dysfunction. To uncover which cognitive domains is most affected, we compared cognitive functioning in brain tumor patients treated with neurosurgery and RT with brain tumor patients treated with neurosurgery alone. Methods: A cross-sectional study assessing cognitive function in 110 patients with a primary brain tumor grades I-III or medulloblastoma (grade IV) treated at Aarhus University Hospital (AUH), Denmark between 2006 and 2016. Two cohorts were established: a cohort of 81 brain tumor patients who had received neurosurgery followed by RT (RT+), and a cohort of 29 brain tumor patients who had only received neurosurgery (RT-). The patients underwent questionnaires and neuropsychological assessment with standardized tests. Results: Mean age was 53.5 years with an average time since diagnosis of 7.3 years. Compared with normative data, lower average scores were observed for the entire group on domains concerning of verbal learning and memory (p < .001), attention and working memory (p < .001), processing speed (p < .001), and executive functioning (p < .001). Compared to RT- patients, RT + patients scored lower on domains concerning processing speed (p = .04) and executive function (p = .05) and had higher impairment frequency on verbal fluency (p = .02) with 16% of patients exceeding 1.5 SD below normative data. Conclusions: Our results indicate that treatment, including RT, for a primary brain tumor may have negative long-term impact on cognitive function, especially on processing speed and executive function.

Prospective memory impairment following whole brain radiotherapy in patients with metastatic brain cancer

OBJECTIVE

To investigate the prospective memory (PM) impairment following whole brain radiotherapy (WBRT) in cancer patients with brain metastases.

METHOD

Eighty-one patients with metastatic brain cancer, agreeing to undergo WBRT, were enrolled and subjected to a battery of cognitive neuropsychological tests, including the mini-mental state examination (MMSE), verbal fluency test (VFT), digit span test (DST), and event-based and time-based prospective memory (EBPM and TBPM) tasks, before and after radiotherapy.

RESULTS

The patients with metastatic brain cancer after WBRT exhibited a significant decrease in the MMSE, DST, VFT, and EBPM scores (t = 6.258, 10.192, 5.361, -5.892, P < 0.01), but nonsignificant decrease in the TBPM scores (t = -1.172, P > 0.05).

CONCLUSION

There is significant EBPM impairment in cancer patients with brain metastases after WBRT, whereas that in the TBPM remained relatively unaffected. The result suggests that EBPM impairment may be as an early cognitive impairment marker in patients with BM who undergo WBRT.

Anatomy and white matter connections of the orbitofrontal gyrus

OBJECTIVE

The orbitofrontal cortex (OFC) is understood to have a role in outcome evaluation and risk assessment and is commonly involved with infiltrative tumors. A detailed understanding of the exact location and nature of associated white matter tracts could significantly improve postoperative morbidity related to declining capacity. Through diffusion tensor imaging–based fiber tracking validated by gross anatomical dissection as ground truth, the authors have characterized these connections based on relationships to other well-known structures.

METHODS

Diffusion imaging from the Human Connectome Project for 10 healthy adult controls was used for tractography analysis. The OFC was evaluated as a whole based on connectivity with other regions. All OFC tracts were mapped in both hemispheres, and a lateralization index was calculated with resultant tract volumes. Ten postmortem dissections were then performed using a modified Klingler technique to demonstrate the location of major tracts.

RESULTS

The authors identified 3 major connections of the OFC: a bundle to the thalamus and anterior cingulate gyrus, passing inferior to the caudate and medial to the vertical fibers of the thalamic projections; a bundle to the brainstem, traveling lateral to the caudate and medial to the internal capsule; and radiations to the parietal and occipital lobes traveling with the inferior fronto-occipital fasciculus.

CONCLUSIONS

The OFC is an important center for processing visual, spatial, and emotional information. Subtle differences in executive functioning following surgery for frontal lobe tumors may be better understood in the context of the fiber-bundle anatomy highlighted by this study.

Feasibility of Hippocampal Avoidance Radiotherapy for Glioblastoma

With improvements in survival for good performance status patients and in specific molecular subtypes of glioblastoma, some patients will survive to develop significant neurocognitive dysfunction. This retrospective planning study quantified hippocampal radiation doses in patients with glioblastoma receiving radical chemo-radiotherapy and compared this with the radiation doses that showed clinical correlation with neurocognitive dysfunction, and evaluated the potential for clinically meaningful hippocampal dose reduction using helical TomoTherapy^®.

STEREOTACTIC RADIATION THERAPY IN PITUITARY ADENOMAS, IS IT BETTER THAN CONVENTIONAL RADIATION THERAPY?

Pituitary radiotherapy (RT) has undergone important progress in the last decades due to the development of new stereotactic techniques which provide more precise tumour targeting with less overall radiation received by the adjacent brain structures. Pituitary surgery is usually first-line therapy in most patients with nonfunctioning (NFPA) and functioning adenomas (except for prolactinomas and large growth hormone (GH) secreting adenomas), while RT is used as second or third-line therapy. The benefits of RT (tumour volume control and, in functional tumours, decreased hormonal secretion) are hampered by the long latency of the effect and the potential side effects. This review presents the updates in the efficacy and safety of the new stereotactic radiation techniques in patients with NFPA, GH-, ACTH- or PRL-secreting pituitary adenomas.

Methods

A systematic review was performed using PubMed and articles/abstracts and reviews detailing RT in pituitary adenomas from 2000 to 2017 were included.

Results

Stereotactic radiosurgery (SRS) and fractionated stereotactic RT (FSRT) provide high rates of tumour control i.e. stable or decrease in tumour size, in all types of pituitary adenomas (median 92 - 98%) at 5 years. Endocrinological remission is however significantly lower: 44-52% in acromegaly, 54-64% in Cushing's disease and around 30% in prolactinomas at 5 years. The rate of new hypopituitarism varies from 10% to 50% at 5 years in all tumour types and as expected increases with the duration of follow-up (FU). The risk for other radiation-induced complications is usually low (0-5% for new visual deficits, cranial nerves damage or brain radionecrosis and extremely low for secondary brain tumours), however longer FU is needed to determine rates of secondary tumours. Notably, in acromegaly, there may be a higher risk for stroke with FSRT.

Conclusion

Stereotactic radiotherapy can be an effective treatment option for patients with persistent or recurrent pituitary adenomas after unsuccessful surgery (especially if residual tumour is enlarging) and/or resistance or unavailability of medical therapy. Comparison with conventional radiation therapy (CRT) is rather difficult, due to the substantial heterogeneity of the studies. In order to evaluate the potential brain-sparing effect of the new stereotactic techniques, suggested by the current data, long-term studies evaluating secondary morbidity and mortality are needed.

Long-term Outcome After Fractionated Radiotherapy for Pituitary Adenoma: The Curse of the Secretory Tumor

OBJECTIVES

To determine the influence of secretory status on long-term outcome after fractionated radiotherapy (RT) for gross residual pituitary adenoma.

MATERIALS AND METHODS

This is a retrospective study of 116 consecutively treated patients who met the following inclusion criteria: tissue diagnosis of pituitary adenoma, visible tumor at the time of RT, treatment with fractionated RT, and imaging follow-up of ≥2 years. Hypersecretion of growth hormone, adrenocorticotrophic hormone, prolactin, or thyroid-stimulating hormone was documented in 30 patients (26%). The RT dose in most (78%) patients was 45 Gy at 1.8 Gy per fraction. The major outcome endpoint is clinical and biochemical control, meaning no growth on follow-up scans and normalization of hypersecretion, if present before RT.

RESULTS

Long-term tumor control was outstanding for nonsecretory tumors: 96% at 10 years. There was a major drop in the control rate of secretory tumors: 10-year clinical and biochemical control was 62% (P<0.0001 vs. 96%). Multivariate analysis confirmed secretory status as the only independent prognostic factor (variables analyzed were sex, age, tumor size, RT dose, and secretory status).

CONCLUSIONS

Secretory pituitary adenomas have a worse prognosis than nonsecretory tumors after 45 to 50 Gy of conventionally fractionated RT. As a result of this finding, our plan is to increase the intensity of RT in secretory tumors, but our data did not evaluate this approach. The treatment guidelines that we currently use in pituitary adenoma are as follows. Radiosurgery (20 to 30 Gy) is our first-choice treatment of a secretory tumor that cannot be completely resected. When treating gross residual pituitary adenoma with fractionated RT, we use the following dose schedules: Nonsecretory: 45 Gy at 1.8 Gy/fraction, once-daily fractionation. Secretory: 54 Gy at 1.8 Gy/fraction once daily or 55.2 Gy at 1.2 Gy/fraction with twice-daily treatment.

The Role of Radiotherapy in Acromegaly

Radiotherapy has, historically, played a central role in the management of acromegaly, and the last 30 years have seen substantial improvements in the technology used in the delivery of radiation therapy. More recently, the introduction of highly targeted radiotherapy, or 'radiosurgery', has further increased the therapeutic options available in the management of secretory pituitary tumors. Despite these developments, improvements in primary surgical outcomes, an increase in the range and effectiveness of medical therapy options, and long-term safety concerns have combined to dictate that, although still deployed in selected cases, the use of radiotherapy in the management of acromegaly has declined steadily over the past 2 decades. In this article, we review some of the main studies that have documented the efficacy of pituitary radiotherapy on growth hormone hypersecretion and summarize the data around its potential deleterious effects, including hypopituitarism, cranial nerve damage, and the development of radiation-related intracerebral tumors. We also give practical recommendations to guide its future use in patients with acromegaly, generally, as a third-line intervention after neurosurgical intervention in combination with various medical therapy options.

Impaired decision making and delayed memory are related with anxiety and depressive symptoms in acromegaly

Evaluation of cognitive function in acromegaly has revealed contradictory findings; some studies report normal cognition in patients with long-term cured acromegaly, while others show attention and memory deficits. Moreover, the presence of affective disorders in these patients is common. Our aim was to evaluate memory and decision making in acromegalic patients and explore their relationship with affective disorders like anxiety and depressive symptoms. Thirty-one patients with acromegaly (mean age 49.5 ± 8.5 years, 14 females and 17 males) and thirty-one healthy controls participated in this study. The Iowa Gambling Task (IGT), Rey Auditory Verbal Learning Test, State-Trait Anxiety Inventory, and Beck Depression Inventory-II (BDI-II) were used to evaluate decision making, verbal memory, anxiety, and depressive symptoms, respectively. Acromegalic patients showed impairments in delayed verbal memory (p < 0.05) and more anxiety and depressive symptoms (p < 0.05) than controls. In the IGT, acromegalic patients presented an altered decision-making strategy compared to controls, choosing a lower number of the safer cards (p < 0.05) and higher number of the riskier cards (p < 0.05). Moreover, multiple correlations between anxiety and depressive symptoms and performance in memory and decision making were found. Impaired delayed memory and decision making observed in acromegalic patients are related to anxiety and depressive symptoms. Providing emotional support to the patients could improve their cognitive function. A key clinical application of this research is the finding that depressive symptoms and anxiety are essentially modifiable factors.

Neurocognitive long-term impact of two-field conventional radiotherapy in adult patients with operated pituitary adenomas

PURPOSE

To assess the long-term impact of postoperative two-field-conventional radiotherapy (RT) on neurocognitive functions of adult patients with operated pituitary adenomas (PA).

METHODS

We selected 124 adult patients with operated PA-56 of whom had also received RT-recorded their main clinical data and performed a neuropsychological assessment in all of them that included 15 standardized tests, and a cerebral SPECT in eight patients. Comparative analyses were carried out on major clinical and neurocognitive domains between irradiated and not irradiated patients, and on cerebral SPECT source.

RESULTS

Compared with non-irradiated patients, irradiated patients performed significantly worse on Barcelona's story recall test (P < 0.001) and arithmetic problems (P < 0.03) and on five categories of the Wisconsin card sorting test, especially on perseverative answers and errors (P < 0.001) without differences in other examined functional domains. RT was the only factor associated with worse results in these tests regardless other clinical and treatment-related variables. Kaplan-Meier analysis suggested that the probability of achieving poorer results with time was related to RT total dose and field-size, type of PA and age at the time of RT. Four of the five SPECTS performed in irradiated patients revealed a similar altered perfusion in the left temporal lobe cortical region.

CONCLUSIONS

In adult patients with operated PA, RT was independently associated with an impairment on verbal memory and executive function, when compared to non-irradiated patients. Our data suggest that diagnosis of acromegaly or Cushing's disease, and age at the time of RT were able to modulate this long-term radio-induced neurocognitive sequelae.

Fractionated stereotactic radiotherapy for large and invasive non-functioning pituitary adenomas: long-term clinical outcomes and volumetric MRI assessment of tumor response

OBJECTIVE

We describe the use of fractionated stereotactic radiotherapy (FSRT) for the treatment of large, invasive, nonfunctioning pituitary adenomas (NFPAs). FSRT is frequently employed for the treatment of residual or recurrent pituitary adenomas.

PATIENTS AND METHODS

Sixty-eight patients with a large residual or recurrent NFPAs were treated between April 2004 and December 2012, including 39 males and 29 females (median age 51 years). Visual defects were present in 34 patients, consisting of visual field defects (n=31) and/or reduced visual acuity (n=12). Forty-five patients had evidence of partial or total hypopituitarism before FSRT. For most of the patients, the treatment was delivered through 5-10 noncoplanar conformal fixed fields using a 6-MV linear accelerator to a dose of 45 Gy in 25 fractions.

RESULTS

At a median follow-up of 75 months (range 12-120 months), the 5- and 10-year actuarial local control were 97 and 91%, respectively, and overall survival 97 and 93%, respectively. Forty-nine patients had a tumor reduction, 16 remained stable, and three progressed. The relative tumor volume reduction measured using three-dimensional (3D) magnetic resonance imaging (MRI) was 47%. The treatment was well tolerated with minimal acute toxicity. Eighteen patients developed partial or complete hypopituitarism. The actuarial incidence of new anterior pituitary deficits was 40% at 5 years and 72% at 10 years. No other radiation-induced complications occurred.

CONCLUSIONS

Our results suggest that FSRT is an effective treatment for large or giant pituitary adenomas with low toxicity.

Brain abnormalities on MRI in non-functioning pituitary adenoma patients treated with or without postoperative radiotherapy

BACKGROUND AND PURPOSE

To assess and compare brain abnormalities on Magnetic Resonance Imaging (MRI) in non-functioning pituitary macro-adenoma (NFA) patients treated with or without postoperative radiotherapy (RT).

MATERIAL AND METHODS

In 86 NFA patients, treated between 1987 and 2008 at the University Medical Center Groningen, white-matter lesions (WMLs), cerebral atrophy, brain infarctions and abnormalities of the temporal lobes and hippocampi were assessed on pre- and post-treatment MRI scans in patients treated with (n=47) or without RT.

RESULTS

The median MRI follow-up time for RT patients was 10 (range 1-22) years and 5 (range 1-21) years in patients treated without RT. In RT patients the cumulative incidence of WMLs was significantly lower compared to patients treated without RT (log-rank test RR 0.49, 95% CI 0.25-0.97, p=.042). The cumulative incidences of cerebral atrophy, brain infarctions, abnormalities of the temporal lobes and hippocampi, and the severity of WMLs and cerebral atrophy ratings were not significantly different between the two treatment groups.

CONCLUSIONS

Brain abnormalities on MRI are not observed more frequently in NFA patients treated with RT compared to patients treated with surgery-alone. Furthermore, RT was not associated with an increased severity of WMLs and cerebral atrophy ratings in this cohort of NFA patients.

Impaired decision-making and selective cortical frontal thinning in Cushing's syndrome

CONTEXT AND OBJECTIVE

Cushing's syndrome (CS) is caused by a glucocorticoid excess. This hypercortisolism can damage the prefrontal cortex, known to be important in decision-making. Our aim was to evaluate decision-making in CS and to explore cortical thickness.

SUBJECTS AND METHODS

Thirty-five patients with CS (27 cured, eight medically treated) and thirty-five matched controls were evaluated using Iowa gambling task (IGT) and 3 Tesla magnetic resonance imaging (MRI) to assess cortical thickness. The IGT evaluates decision-making, including strategy and learning during the test. Cortical thickness was determined on MRI using freesurfer software tools, including a whole-brain analysis.

RESULTS

There were no differences between medically treated and cured CS patients. They presented an altered decision-making strategy compared to controls, choosing a lower number of the safer cards (P < 0·05). They showed more difficulties than controls to learn the correct profiles of wins and losses for each card group (P < 0·05). In whole-brain analysis, patients with CS showed decreased cortical thickness in the left superior frontal cortex, left precentral cortex, left insular cortex, left and right rostral anterior cingulate cortex, and right caudal middle frontal cortex compared to controls (P < 0·001).

CONCLUSIONS

Patients with CS failed to learn advantageous strategies and their behaviour was driven by short-term reward and long-term punishment, indicating learning problems because they did not use previous experience as a feedback factor to regulate their choices. These alterations in decision-making and the decreased cortical thickness in frontal areas suggest that chronic hypercortisolism promotes brain changes which are not completely reversible after endocrine remission.

Pituitary disease mortality: is it fiction?

During the last 20 years a tremendous improvement in the care of patients with pituitary tumors and of hypopituitarism has been achieved. If we resolve most of the possible causes of the increased cardiovascular disease and stroke mortality a normal survival is expected in these patients. Recently, a large population based study showed a decline in the risk of non-fatal stroke and of non-fatal cardiac events in GH deficient patients. This improvement was achieved by complete hormone replacement, including long term GH replacement, together with prescription of cardio protective drugs. If we follow the latest achievements in pituitary imaging, surgery techniques, hormone substitutions, cardio protective medications, we would expect a normal longevity in these patients. This review will focus on; (1) pituitary insufficiencies and hormone substitutions, (2) modes of cranial radiotherapy, and (3) new techniques in the surgery of a pituitary adenoma.

Effects of previous growth hormone excess and current medical treatment for acromegaly on cognition

BACKGROUND

In untreated acromegaly patients, decreased cognitive functioning is reported to be associated with the degree of growth hormone (GH) and IGF-1 excess. Whether previous GH excess or current medical treatment for acromegaly specifically affects cognition remains unclear. The aim of this study was to compare cognitive functioning of patients who are treated for acromegaly with patients with non-functioning pituitary adenomas (NFA). In addition, we assessed the influence of prolonged medical treatment after initial transsphenoidal surgery on cognition.

DESIGN

In this cross-sectional study, 74 patients participated, who were treated for acromegaly (n = 50; median [interquartile range] age: 53 [45-65] years) or NFA (n = 24; age: 63 [59-70] years). The NFA patients were selected for a high likelihood of normal GH secretion based on an IGF-1 z-score within the normal range (> -2) and zero or one axis substituted. Of the acromegaly patients, 28 had achieved remission, while 22 were biochemically controlled with long-acting somatostatin analogues and/or pegvisomant. Memory and executive functioning were assessed by the 15 Words Test and the Ruff Figural Fluency Test, and reported as z-scores.

RESULTS

The total patient group scored significantly poorer than the reference population on memory and executive functioning (P < 0·001). However, cognitive test performance was not significantly different between acromegaly patients with a persistent disease, acromegaly patients in remission and NFA patients.

CONCLUSION

The total patient group scored worse compared with reference populations. We found no association between previous GH excess and cognition. In addition, current medical treatment for GH excess in acromegaly was not related to memory and executive functioning.

Physical activity, cognitive function, and brain health: what is the role of exercise training in the prevention of dementia?

Tor preventive measures are necessary to attenuate the increased economic and social burden of dementia. This review will focus on the potential for physical activity and exercise training to promote brain health and improve cognitive function via neurophysiological changes. We will review pertinent animal and human research examining the effects of physical activity on cognitive function and neurophysiology. We will discuss cross-sectional and longitudinal studies addressing the relationship between neurocognitive health and cardiorespiratory fitness or habitual activity level. We will then present and discuss longitudinal investigations examining the effects of exercise training on cognitive function and neurophysiology. We will conclude by summarizing our current understanding of the relationship between physical activity and brain health, and present areas for future research given the current gaps in our understanding of this issue.