The Interrelationship between Insulin-Like Growth Factor 1, Apolipoprotein E ε4, Lifestyle Factors, and the Aging Body and Brain

Aging is associated with a decrease in body and brain function and with a decline in insulin-like growth factor 1 levels. The observed associations between alterations in insulin-like growth factor 1 levels and cognitive functioning and Mild Cognitive Impairment suggest that altered insulin-like growth factor 1 signaling may accompany Alzheimer's disease or is involved in the pathogenesis of the disease. Recent animal research has suggested a possible association between insulin-like growth factor 1 levels and the Apolipoprotein E ε4 allele, a genetic predisposition to Alzheimer's disease. It is therefore hypothesized that a reduction in insulin-like growth factor 1 signaling may moderate the vulnerability to Alzheimer's disease of human Apolipoprotein E ε4 carriers. We address the impact of age-related decline of insulin-like growth factor 1 levels on physical and brain function in healthy aging and Alzheimer's disease and discuss the links between insulin-like growth factor 1 and the Apolipoprotein E ε4 polymorphism. Furthermore, we discuss lifestyle interventions that may increase insulin-like growth factor 1 serum levels, including physical activity and adherence to a protein rich diet and the possible benefits to the physical fitness and cognitive functioning of the aging population.

Adjunctive memantine in clozapine-treated refractory schizophrenia: an open-label 1-year extension study

BACKGROUND

In a recent placebo-controlled, double-blind crossover trial (n = 52), significant beneficial effects on memory (d = 0.30) and negative symptoms (d = 0.29) were found after 12 weeks of memantine augmentation in patients with clozapine-refractory schizophrenia. In this open-label 1-year extension study we report the long-term effects and tolerability of memantine add-on therapy to clozapine.

METHOD

Completers of the first trial who experienced beneficial effects during 12 weeks of memantine treatment received memantine for 1 year. Primary endpoints were memory and executive function using the Cambridge Neuropsychological Test Automated Battery, the Positive and Negative Syndrome Scale (PANSS), and the Clinical Global Impression Severity Scale (CGI-S).

RESULTS

Of 31 randomized controlled trial completers who experienced beneficial effects from memantine, 24 received memantine for 1 year. The small improvement in memory found in the memantine condition in the placebo-controlled trial remained stable in the extension study. Executive function did not improve. After 26 weeks of memantine add-on therapy to clozapine, PANSS negative symptoms (r = 0.53), PANSS positive symptoms (r = 0.50) and PANSS total symptoms (r = 0.54) significantly improved. Even further significant improvement in all these measures was observed between 26 weeks and 52 weeks of memantine, with effect sizes varying from 0.39 to 0.51. CGI-S showed a non-significant moderate improvement at 26 weeks (r = 0.36) and 52 weeks (r = 0.34). Memantine was well tolerated without serious adverse effects.

CONCLUSIONS

In the 1-year extension phase the favourable effect of adjunctive memantine on memory was sustained and we observed further improvement of negative, positive and overall symptoms in patients with clozapine-treated refractory schizophrenia.

Short and long-term effects of sham-controlled prefrontal EEG-neurofeedback training in healthy subjects

OBJECTIVE

In this study we evaluated long-term effects of frontal beta EEG-neurofeedback training (E-NFT) on healthy subjects. We hypothesized that E-NFT can change frontal beta activity in the long-term and that changes in frontal beta EEG activity are accompanied by altered cognitive performance.

METHODS

25 healthy subjects were included and randomly assigned to active or sham E-NFT. On average the subjects underwent 15 E-NFT training sessions with a training duration of 45 min. Resting-state EEG was recorded prior to E-NFT training (t1) and in a 3-year follow-up (t3).

RESULTS

Compared to sham E-NFT, which was used for the control group, real E-NFT increased beta activity in a predictable way. This increase was maintained over a period of three years post training. However, E-NFT did not result in significantly improved cognitive performance.

CONCLUSION

Based on our results, we conclude that EEG-NFT can selectively modify EEG beta activity both in short and long-term.

SIGNIFICANCE

This is a sham controlled EEG neurofeedback study demonstrating long-term effects in resting state EEG.

Early-stage cognitive impairment in Parkinson's disease and the influence of dopamine replacement therapy

BACKGROUND AND PURPOSE

The aim of this study was to establish the cognitive profile of newly diagnosed untreated (de novo) patients with Parkinson's disease (PD) and more advanced, treated patients, and to determine the effects of dopamine (DA) replacement therapy.

METHODS

A cohort of 23 de novo patients, 55 mild to moderately advanced, medicated PD patients and 21 healthy controls participated. Cognitive tests included the Cambridge Examination for Mental Disorders and a battery of neuropsychological tests taken from the Cambridge Neuropsychological Test Automated Battery and the Vienna Test System.

RESULTS

De novo patients with PD were more impaired in working memory strategy use than healthy controls and treated patients with PD. Furthermore, the generation of random motor behaviour was more impaired in both de novo and treated PD patients than in healthy controls. Correlation analysis revealed that in treated patients with PD, ascending doses of dopaminergic medication were associated with poorer performance on a pattern recognition task.

CONCLUSION

Selective impairments in strategy use and the generation of random motor behaviour are a very early feature of PD and might be of predictive value in further frontal cognitive deterioration. Furthermore, DA replacement therapy seems to improve frontal lobe function (strategy use) and worsen temporal lobe function (visual memory).

The relationship between IGF-I concentration, cognitive function and quality of life in adults with Prader-Willi syndrome

Mental retardation is one of the clinical characteristics of Prader-Willi syndrome (PWS) and in part of the patients growth hormone deficiency is demonstrable. Cognitive function seems to be influenced by insulin-like growth factor I (IGF-I); however, little is known about cognitive function in relation to IGF-I levels in PWS adults. The aim of the present study was to evaluate cognitive function in adult PWS patients in comparison to healthy siblings and to investigate whether there is a correlation between cognitive function and IGF-I levels. Anthropometric measurements, IGF-I levels, quality of life (QoL), Appetite Assessment Score, IQ (GIT and Raven) and cognitive function (by four subtests of the Cambridge Neuropsychological Automated Testing Battery, CANTAB) were evaluated in PWS patients and their healthy siblings served as control group. PWS patients had significantly lower IGF-I levels, IQ and QoL when compared to controls. Reaction times were longer and performance was worse on CANTAB subtests in PWS adults. IGF-I on one hand and IQ, Appetite Assessment Score and cognitive performance on the other hand seem to be correlated in PWS patients. In conclusion, IGF-I levels, IQ and QoL are significantly lower in PWS subjects when compared to healthy siblings. In PWS adults, temporal as well as prefrontal cognitive functions are impaired. Higher IGF-I levels appear to be related to better intellectual skills and faster temporal memory processing in PWS patients.

Increased cortico-cortical functional connectivity in early-stage Parkinson's disease: an MEG study

We set out to determine whether changes in resting-state cortico-cortical functional connectivity are a feature of early-stage Parkinson's disease (PD), explore how functional coupling might evolve over the course of the disease and establish its relationship with clinical deficits. Whole-head magnetoencephalography was performed in an eyes-closed resting-state condition in 70 PD patients with varying disease duration (including 18 recently diagnosed, drug-naive patients) in an "OFF" medication state and 21 controls. Neuropsychological testing was performed in all subjects. Data analysis involved calculation of three synchronization likelihood (SL, a general measure of linear and non-linear temporal correlations between time series) measures which reflect functional connectivity within (local) and between (intrahemispheric and interhemispheric) ten major cortical regions in five frequency bands. Recently diagnosed, drug-naive patients showed an overall increase in alpha1 SL relative to controls. Cross-sectional analysis in all patients revealed that disease duration was positively associated with alpha2 and beta SL measures, while severity of parkinsonism was positively associated with theta and beta SL measures. Moderately advanced patients had increases in theta, alpha1, alpha2 and beta SL, particularly with regard to local SL. In recently diagnosed patients, cognitive perseveration was associated with increased interhemispheric alpha1 SL. Increased resting-state cortico-cortical functional connectivity in the 8-10 Hz alpha range is a feature of PD from the earliest clinical stages onward. With disease progression, neighboring frequency bands become increasingly involved. These findings suggest that changes in functional coupling over the course of PD may be linked to the topographical progression of pathology over the brain.

Slowing of oscillatory brain activity is a stable characteristic of Parkinson's disease without dementia

Extensive changes in resting-state oscillatory brain activity have recently been demonstrated using magnetoencephalography (MEG) in moderately advanced, non-demented Parkinson's disease patients relative to age-matched controls. The aim of the present study was to determine the onset and evolution of these changes over the disease course and their relationship with clinical parameters. In addition, we evaluated the effects of dopaminomimetics on resting-state oscillatory brain activity in levodopa-treated patients. MEG background oscillatory activity was studied in a group of 70 Parkinson's disease patients with varying disease duration and severity (including 18 de novo patients) as well as in 21 controls that were age-matched to the de novo patients. Whole head 151-channel MEG recordings were obtained in an eyes-closed resting-state condition. Levodopa-treated patients (N = 37) were examined both in a practically defined 'OFF' as well as in the 'ON' state. Relative spectral power was calculated for delta, theta, low alpha, high alpha, beta and gamma frequency bands and averaged for 10 cortical regions of interest (ROIs). Additionally, extensive clinical and neuropsychological testing was performed in all subjects. De novo Parkinson's disease patients showed widespread slowing of background MEG activity relative to controls. Changes included a widespread increase in theta and low alpha power, as well as a loss of beta power over all but the frontal ROIs and a loss of gamma power over all but the right occipital ROI. Neuropsychological assessment revealed abnormal perseveration in de novo patients, which was associated with increased low alpha power in centroparietal ROIs. In the whole group of Parkinson's disease patients, longer disease duration was associated with reduced low alpha power in the right temporal and right occipital ROI, but not with any other spectral power measure. No association was found between spectral power and disease stage, disease severity or dose of dopaminomimetics. In patients on levodopa therapy, a change from the 'OFF' to the 'ON' state was associated with decreases in right frontal theta, left occipital beta and left temporal gamma power and an increase in right parietal gamma power. Widespread slowing of oscillatory brain activity is a characteristic of non-demented Parkinson's disease patients from the earliest clinical stages onwards that is (largely) independent of disease duration, stage and severity and hardly influenced by dopaminomimetic treatment. Some early cognitive deficits in Parkinson's disease appear to be associated with increased low alpha power. We postulate a role for hypofunctional non-dopaminergic ascending neurotransmitter systems in spectral power changes in non-demented Parkinson's disease patients.

Age-related cognitive effects of ECT and ECT-induced mood improvement in depressive patients

This explorative study investigated the interaction between electroconvulsive therapy (ECT) treatment-effect, reduced depression, and neuropsychological outcome in relation to age. Follow-up neuropsychological assessment was conducted with depressive patients treated with ECT. From a potential sample of 45 patients, the neuropsychological measures (pre-ECT, three times post-ECT, up to 12 months) and clinical data from the remaining 21 patients who completed all assessments were evaluated (mean age=56.76; SD=14.12; range, 33-79). ECT resulted in a decrease in the depression scores. A distinct impact of ECT and depression decrease on cognitive domains was found. Depression alleviation was mainly associated with improvement in cognitive domains such as memory, information processing, and executive function. ECT improved cognitive domains such as information processing and perception. Short-term cognitive improvement was greater in older patients but showed an increase similar to that at long-term follow-up in younger patients (<60). Current findings provide evidence that ECT may improve cognitive functioning in nondemented elderly, which has strong clinical relevance concerning the use of ECT.

The relation between insulin-like growth factor I levels and cognition in healthy elderly: a meta-analysis

OBJECTIVE

Insulin-like growth factor I (IGF-I) levels and cognitive functioning decrease with aging. Several studies report positive correlations between IGF-I levels and cognitive functioning in healthy elderly. However, because of controversial data no definitive conclusions can be drawn concerning the relation between IGF-I and cognition. Therefore, we carried out a meta-analysis on studies that report on the relation between IGF-I and cognition in healthy elderly.

DESIGN

We searched the electronic databases for articles about IGF-I and cognition. Studies from 1985 to January 2005 are included. Two reviewers independently extracted data on study design and cognitive outcomes. Thirteen studies on IGF-I and cognition in elderly, with a total number of 1981 subjects, met the inclusion criteria. On the data from these studies meta-analyses were carried out by means of the program Comprehensive Meta-analysis using a random effects model.

RESULTS

Pooled effects show that IGF-I levels in healthy elderly have a positive correlation with cognitive functioning, which appeared to be mainly measured with the mini mental state examination (MMSE). The effect size is 0.6, which indicates the presence of a large positive relationship between IGF and cognition in healthy elderly.

CONCLUSION

These meta-analyses showed an overall relationship between IGF-I levels and cognitive functioning in healthy elderly. Further studies should be performed to clarify the role of IGF-I substitution in preserving cognitive functions with aging.

The influence of growth hormone (GH) substitution on patient-reported outcomes and cognitive functions in GH-deficient patients: a meta-analysis

OBJECTIVE

The influence of growth hormone (GH) replacement on patient-reported outcomes (i.e., quality of life, health status and well-being) and cognitive functioning in GH-deficient adults is controversial.

DESIGN

We carried out a meta-analysis of clinical trials concerning the influence of GH substitution on patient-reported outcomes and cognitive functions (studies were selected from 1985 to 2004). The results of individual studies were combined in a series of meta-analyses using a random effects model. Effects of GH replacement in GH-deficient adults were compared to baseline and/or placebo.

RESULTS

Fifteen studies on GH and patient-reported outcomes were included (830 patients, follow-up 3-50 months). Four of these studies also provided data on cognitive functions (85 patients, follow-up 6-12 months). Relative to baseline, GH treatment is found to have a large effect on patient-reported outcomes at 3 months, a medium effect at 6 months and a small effect at 12 months. With respect to the median treatment duration of 6 months placebo appears to be as effective as GH substitution. Cognitive functioning does not improve after 6 months of GH substitution, relative to baseline.

CONCLUSION

This meta-analysis provides no evidence that GH improves patient-reported outcomes in GH-deficient patients. As the amount of cognitive data was too limited to allow for comparisons with placebo, from the present meta-analysis no conclusions can be drawn with respect to the impact of GH treatment on cognition.

Nutritional intake and daily functioning of psychogeriatric nursing home residents

BACKGROUND

The level of observed daily functioning in psychogeriatric nursing home patients may be related to nutrient intake and body weight.

OBJECTIVE

Relationships between nutrient intake, weight and daily functioning were assessed in nursing home residents.

DESIGN

A descriptive, correlational design added by a experimental (repeated measurements) model was used to compare 3-day food records of 90 elderly psycho-geriatric residents filled in by the caretakers every 8 weeks during a period of 6 months. Nutrient intakes and cognitive scores were averaged over the total investigation period and studied separately at week 0, 8, 16 and 24. High and a low nutrient intake groups were compared with respect to daily functioning, which was measured by a Dutch geriatric nursing scale, the Zorg Index geriatrie (ZIG).

RESULTS

Body weight was higher in the high niacin, high vitamin B-6 and high vitamin C intake groups. Unexpectedly, higher vitamin intakes were associated with a worse daily functioning. Results are explained by the fact that patients with a lower cognitive level are more dependent on their caregivers, thereby receiving more help with eating. Consequently, more severely demented patients have a higher intake of energy and nutrients.

CONCLUSION

In order to optimize the effect of dietary vitamin supplementation in the total severity range of psycho-geriatric residents, caregivers should also pay attention to the eating habits of less dependent patients.

Effects of an oral mixture containing glycine, glutamine and niacin on memory, GH and IGF-I secretion in middle-aged and elderly subjects

Aging is associated with declining activity of the growth hormone-insulin-like growth factor-I (GH-IGF-I) axis and with a decrease in cognitive function. The stimulatory effect of an orally administered nutritional supplement, mainly containing glycine, glutamine and niacin on the GH-IGF-I axis and on mood and cognition was investigated. Forty-two healthy subjects (14 men and 28 women, aged 40-76 years) were enrolled in a randomised, double blind, placebo-controlled trial. They received 5 g of a nutritional supplement or placebo, twice daily orally for a period of 3 weeks. At baseline and after 3 weeks, blood was collected for measurement of serum GH and IGF-I levels and mood and cognitive function were tested. The nutritional supplement ingestion for 3 weeks was found to increase serum GH levels with 70% relatively to placebo, whereas circulating IGF-I levels did not change. Mean GH (+/- SD) increased in this group from 3.23 (+/- 4.78) to 4.67 mU/l (+/- 5.27) (p = 0.03). GH increase was not associated with improvement in mood or memory. Correlation analyses, however, revealed that individual increases in IGF-I, but not GH, were associated with improved memory and vigour. It is concluded that an oral mixture of glycine, glutamine and niacin can enhance GH secretion in healthy middle-aged and elderly subjects.

Deficits on Corsi's block-tapping task in early stage Parkinson's disease

Cognitive deficits in Parkinson's disease (PD) include disturbances in working memory. We examined sequential visuo-spatial memory span by means of an adaptation of the Corsi Block-Tapping Task in groups of medicated (n=14) and non-medicated (n=15) patients with early stage PD, and in control subjects (n=22). A deficit in memory span was found in medicated patients with early stage PD relative to controls. There were no differences between non-medicated patients relative to either controls or medicated patients. A decrease in sequential visuo-spatial memory span appears to be a relatively early feature of PD and most likely reflects executive rather than mnemonic dysfunction.

Quality of life of growth hormone (GH) deficient young adults during discontinuation and restart of GH therapy

The present study evaluates the effects of one year of discontinuation and one year of growth hormone (GH) treatment on quality of life (QoL) in young adults with childhood-onset growth hormone deficiency (CO-GHD). Twenty-two subjects (14 males, 8 females; 11 isolated growth hormone deficient [IGHD], 11 multiple pituitary hormone deficient [MPHD]), aged between 15 and 22 years, on ongoing GH treatment were assessed during one year of discontinuation. Thereafter, 9 of these patients, who were found to be still GH deficient (GHD), added by 11 newly recruited GHD patients who also were not treated in the preceding year (in total 10 males and 10 females, aged between 17 and 27, 5 IGHD, 15 MPHD), restarted GH treatment for one year. During discontinuation and restart of GH treatment somatic and psychological assessments took place every 6 months. In the first 6 months of the GH discontinuation period insulin-like growth factor I (IGF-I) level significantly declined whereas no further decrease in IGF-I was seen after month 6. The number of psychological complaints and depression increased only during the first 6 months of discontinuation. Across the 12-month of discontinuation tension increased in MPHD and decreased in IGHD patients. Only in the first 6 months of GH treatment IGF-I level increased, anxiety decreased and QoL improved. Depression scores tended to decrease across the 12 month treatment period. During the 2-year discontinuation and treatment period intra-subject IGF-I level was negatively correlated with depression, fatigue, tension and anxiety and positively with vigor and memory. At the end of the treatment period all psychometric parameters were similar or even improved compared to those at the start of the discontinuation period. It is concluded that one year discontinuation of GH treatment leads to a decrease in QoL within 6 months which effect is counteracted within 6 months after restart of GH treatment.

The influence of computer experience on visuo-motor control: implications for visuo-motor testing in Parkinson's disease

Abnormalities in visuo-motor control have repeatedly been reported in Parkinson's disease (PD) patients. In the more recent studies, tasks measuring visuo-motor performance are usually computerised tasks requiring the use of a mouse-like manipulandum. In healthy subjects, previous computer mouse experience can influence performance in computerised visuo-motor tasks. We, therefore, investigated the potential confounding effect of mouse experience in a visuo-motor task used in PD patients, the visuo-motor testing (VMT) system, and its concurrent usefulness in the diagnosis of PD. Our study population included 49 early PD patients and 31 controls. The VMT system involves moving a pointer over a sinusoidal path displayed on a computer screen by moving an unseen digitiser mouse over a tablet. In both PD patients and controls, subjects with low mouse experience scored worse than subjects with high mouse experience on variables measuring movement accuracy, direction and speed. After correction for mouse experience the aforementioned deficits were still present in PD patients with low mouse experience. However, PD patients with high mouse experience only showed deficits in movement accuracy. It would seem that previous mouse experience can at least partly compensate for deficits in directional control and speed in PD patients, implying a possible role for training in the treatment of functional motor impairments in PD. Future studies using computerised psychomotor tasks should take sufficient precautions to avoid potential confounding effects of mouse experience. The present data further suggest that only accuracy of visuo-motor control might be a useful parameter in the (early) diagnosis of PD.

Cranial electrostimulation (CES) in patients with probable Alzheimer's disease

In one study, behavioral disorders of patients with vascular dementia reacted positively to cranial electrostimulation (CES). In the present study, it was examined whether CES could improve cognition and (affective) behavior in patients with probable Alzheimer's disease (AD). Eighteen AD patients, divided into an experimental and a placebo group, were treated for 30 min per day, 5 days a week, for 6 weeks. No improvements in cognition and (affective) behavior were found after CES.

Motor perseveration is an early sign of Parkinson's disease

Perseveration in the generation of random motor behavior was examined by means of the Vienna perseverance task in groups of de novo (n = 18) and treated (n = 18) patients with early PD, and in control subjects (n = 18). In comparison with control subjects, both the de novo and treated patients with PD were relatively unable to generate random motor sequences, indicating a decreased ability to switch cortical behavioral programs in PD. An impairment of random motor generation appears to be a very early feature of PD.

Quality of life and cognitive function in patients with pituitary insufficiency

This review is concerned with the psychosocial functioning and the quality of life in patients with pituitary insufficiency who are receiving conventional hormone replacement therapy. The possible negative effects of pituitary surgery, treatment with irradiation, and suboptimal replacement regimens with hormones other than growth hormone on mood, behaviour and cognitive functioning are discussed. The influence of growth hormone deficiency per se, and the outcome of growth hormone therapy in adult patients are addressed in detail. A possible mechanism for a direct effect of growth hormone on the brain is presented.

Growth hormone, insulin-like growth factor I and cognitive function in adults

This review focuses on the possible contribution of the growth hormone (GH)-insulin-like growth factor I (IGF-I) axis to cognitive function. Binding sites for GH and IGF-I are found in various areas of the brain. Their distribution suggests that GH and IGF-I contribute to the function of the hippocampus, a brain structure important for the maintenance of cognitive functions such as learning and memory. Evidence for cognitive deficits in GH-deficient individuals has been found in various studies, some of which have shown that these deficits can be reversed by GH substitution therapy. In addition to examining conditions of GH deficiency, this article reviews studies evaluating the correlation between the cognitive deficits associated with ageing and age-related decreases in GH or IGF-I secretion. Based on the available data, one might hypothesize that relative GH or IGF-I deficiency could contribute to the deterioration of cognitive functions observed in the elderly.

Tyrosine improves cognitive performance and reduces blood pressure in cadets after one week of a combat training course

The effects of the amino acid tyrosine on cognitive task performance were studied on a group of 21 cadets during a demanding military combat training course. In addition, the effects on mood, blood pressure and the norepinephrine metabolite MHPG were determined. Ten subjects received five daily doses of a protein-rich drink containing 2 g tyrosine, and 11 subjects received a carbohydrate rich drink with the same amount of calories (255 kcal). Assessments were made both immediately prior to the combat course and on the 6th day of the course. The group supplied with the tyrosine-rich drink performed better on a memory and a tracking task than the group supplied with the carbohydrate-rich drink. In addition, the supplementation of tyrosine decreased systolic blood pressure. No effects on mood were found. These findings suggest that supplementation with tyrosine may, under operational circumstances characterized by psychosocial and physical stress, reduce the effects of stress and fatigue on cognitive task performance.

The influence of growth hormone (GH) deficiency and GH replacement on quality of life in GH-deficient patients

The total absence of hormones such as cortisol or thyroxine causes death within weeks. Lack of estrogen or testosterone is followed by infertility and impaired sexual functioning. Relative deficiencies of almost all classical hormones have a substantial impact on quality of life (QOL). However, in contrast to virtually all aspects of metabolism, QOL is difficult to measure. Only recently have tests been developed to assess general QOL, whereas specific tests address those aspects of QOL affected only in specific situations or disease states. For example, in rheumatoid arthritis and other chronic disabling diseases, the use of measures of QOL to assess treatment modalities is almost routine. In diseases with overt metabolic disturbances attention is generally focused on changes in metabolic parameters and the issue of QOL is neglected. Although very few practising endocrinologists will not support the idea that they specialize in improving QOL, its assessment in patients with endocrinological disorders began only recently--in patients with growth hormone (GH) deficiency only 10 years ago. It became apparent that GH deficiency in adult life is unmistakably followed by changes in parameters that determine QOL. In adults with childhood-onset GH deficiency, the unemployment rate is higher and the marriage rate lower than in the general population. Another symbol of success in life, the possession of a driver's licence, is less frequently attained by these patients. Most patients with adult-onset GH deficiency score unfavourably in questionnaires such as the Nottingham Health Profile. GH substitution is now available on a scale large enough to enable studies to be made of the effects on QOL in adults. The first studies were reported in 1989. However, only in the last few years have studies appeared in which sufficient number of patients and sufficient length of treatment were reported to allow a more objective judgement of the effectiveness of GH substitution. Although there is still room for improvement in the methods used to assess the effects of GH treatment on QOL in GH-deficient adults, there is now little doubt as to its beneficial effect.

Cognitive changes during growth hormone replacement in adult men

The present study evaluates the effects of 2 years of growth hormone (GH) replacement therapy on psychological well-being and cognitive performance in adults with childhood-onset growth hormone deficiency (CO-GHD). A total of 48 GHD adult men (mean age: 27 years) were randomly assigned to one of four treatment groups: placebo treatment, or GH replacement in a dose of 1, 2, or 3 IU/m2, respectively. Placebo treatment was given for 6 months. Psychological assessments were made every 6 months. Assessments included somatic and psychological complaints, depression, fatigue, vigor, tension, state/trait anxiety, iconic memory, short-term memory, long-term memory and perceptual-motor skill. GH treatment was considered physiological if the observed insulin-like growth factor-I (IGF-I) levels were within the normal range. It was considered supraphysiological if serum IGF-I rose to a value exceeding the upper normal limit. During the placebo-controlled phase of the study the changes in memory performance were positively correlated to the GH induced changes in serum IGF-I concentration and, more weakly, to the daily GH substitution dose. At 6 months memory only had improved in the group receiving supraphysiological GH treatment, but not in the group of patients who had a normalization of serum IGF-I. However, after 1 year of treatment a normalization of memory functioning was found in both groups of patients and this was preserved during the 2nd year of treatment. No changes were observed in psychological well-being and perceptual-motor skill. We conclude that GH replacement improves memory function in adults with CO-GHD. It has no effect on psychological well-being or perceptual-motor skill. Supraphysiological treatment accelerates the recovery of memory performance. However, the long-term effects are not different from those achieved with physiological GH replacement.

The influence of type of information, somatization, and locus of control on attitude, knowledge, and compliance with respect to the triphasic oral contraceptive Tri-Minulet

The possibility of improving attitude, knowledge, and compliance with respect to the oral contraceptive (OC) Tri-Minulet (Wyeth, Hoofddorp, The Netherlands) by supplying brochures and information on audiotape was studied in 1239 healthy women, aged between 15 and 45. One group was orally informed, a second group additionally received brochures, and a third group received, in addition to the above two, information on audiotape. At baseline and after the first and third cycle, OC-attitude, missed pill handling, and compliance were assessed. Somatization and locus of control were also assessed. Knowledge of the medical advantages of the pill was increased by the audiotape and the compliance by the combination of brochures and audiotape. The brochures alone and in combination with tape improved the knowledge of how to handle missed pills. In somatizers and externals, who particularly showed a poor knowledge and a negative pill-attitude, this knowledge was increased by the combination of brochures and tape.

Cognitive impairments and mood disturbances in growth hormone deficient men

In order to establish whether reported psychological complaints in hypopituitary adults are related to growth hormone (GH) deficiency or other pituitary hormone deficiencies, emotional well-being and cognitive performance were evaluated in 31 men with multiple pituitary hormone deficiencies (MPHD) and in 17 men with isolated growth hormone deficiency (IGHD). Assessments included evaluation of somatic and psychological complaints, depression, fatigue, vigor, tension, state and trait anxiety, iconic memory, short-term memory, long-term memory and perceptual-motor skill. The control group consisted of 41 healthy men, matched for age. Growth hormone secretion was more severely impaired in MPHD than in IGHD patients. Despite oral replacement therapy, MPHD patients also had lower serum testosterone levels than IGHD subjects. The MPHD patients were found to have lower vigor scores, higher state anxiety scores, worse perceptual-motor skill and worse memory performance than controls. In contrast, IGHD patients only showed subnormal memory performance. It was concluded, therefore, that the cognitive impairment in both MPHD and IGHD was related to GH deficiency. The subnormal vigor scores in MPHD patients were attributed to the reduced testosterone levels. The worse perceptual-motor skill in MPHD patients might be related specifically to ACTH deficiency. Finally, the higher state anxiety in MPHD was attributed to a low self-esteem, which may be the psychological consequence of the hypogonadal appearance these patients have. We conclude that, from a psychological point of view, MPHD and IGHD adult patients are quite distinct groups.

Pupillometric assessment of compensatory effort in a memory search task under physical and pharmacologically-induced suboptimal states

Extensive research has shown that the phasic pupil size (peak level on each trial) is a sensitive measure of the degree of mental effort demanded by a task. In the present study, the validity of the pupil response as an index of mental effort in suboptimal conditions was investigated. Thirteen males (19-29 years) performed a memory and display-search task in a practice session, followed in random order by an oxazepam session, a placebo session, a physical exercise session, and a control session. After both oxazepam and physical exercise, decision times increased, but pupil response increased only after physical exercise. This result was explained by the possibility that under physical fatigue, compensatory effort was exerted, whereas under drug-induced fatigue, subjects seemed unable to compensate for the performance decrement. The pupil response appears to be a valuable tool for gaining more insight into different effects of suboptimal states.

Effect of tyrosine on cognitive function and blood pressure under stress

The effects of tyrosine on mood, performance, heart rate and blood pressure of 16 healthy young subjects were assessed. Subjects were tested on two separate days, one test session after ingestion of 100 mg/kg tyrosine and the other test session after placebo, in random order. While performing a number of stress sensitive tasks, subjects were exposed to a stressor consisting of 90 dB noise. Tyrosine was found to improve the performance on two cognitive tasks, which were performed 1 h after administration of the medication and which could be characterized as highly sensitive to stress. In addition, tyrosine decreased diastolic blood pressure 15 min after ingestion, while 1 h after ingestion diastolic blood pressure was the same with tyrosine and placebo. No effects on mood, systolic blood pressure and heart rate were found.

Effect of depression on psychomotor skills, eye movements and recognition-memory

In this study 12 depressed outpatients were compared to 12 healthy controls with respect to their performance on a number of cognitive tasks, including a recognition-memory task, and their eye movements and pupil size were recorded while watching a traffic film. The recognition-memory task consisted of words with intermediate hedonic tone (neutral words), words with high hedonic tone ('good' words) and words with low hedonic tone ('bad' words). Patients performed slower on perceptual-motor tasks which could be characterized as effort-demanding, while no difference between groups was found on effortless tasks. In addition, the range of horizontal eye movements, an indication of visual span, was found to be less in patients. Signal-detection analysis on the recognition-memory data showed an impairment of 'pure' memory in depressives. Analyses on response bias indicated that patients had more false alarms, but only with respect to good words. It is concluded that patients exhibit cognitive deficits, including memory impairment, a narrower visual span and a risky response strategy on good words, which may be an indication of the trouble patients have in processing emotionally toned words.

Use of a monophasic, low-dose oral contraceptive in relation to mental functioning

The objective of the study was to evaluate the effect of Minulet, a new low-dose oral contraceptive on mood in two groups and to compare the effect with a control group of women not taking oral contraceptives (OC). The women participating were between 16 and 45 years of age. They completed the Amsterdam Mood Questionnaire (AMQ) and the Sickness Impact Profile (SIP) three times. They were filled in before treatment started, after taking Minulet for one month and then again after three months. The questionnaires were filled in by a group of 200 women who had not taken OC before (starters), and by a second group of 370 women who were already taking OC (switchers). A group of 140 women who did not use any OC during the study served as a control group. These women also filled in the same questionnaires, both at the start, and after one and three months. As far as the AMQ was concerned, the switchers appeared in the initial measurement to have significantly higher scores (that is to say, a worse mood) for "tiredness", "depression", "moodiness", "anxiety" and "anger", than those of the starters and the control group. Moreover, the switchers had reduced scores (that is to say, an improved mood) on the AMQ-scales during their use of Minulet compared to their initial use of oral contraceptives. The scores of the starters and the control group on the AMQ-scales remained unchanged on all three measurements. It can be concluded from this that these groups felt as well as they did before.(ABSTRACT TRUNCATED AT 250 WORDS)

Vitamin B-6 supplementation in elderly men: effects on mood, memory, performance and mental effort

This study evaluates the effects of vitamin B-6 supplementation (20 mg pyridoxine HCL daily for 3 months) on mood and performance in 38 self-supporting healthy men, aged between 70-79 years. Effects were compared with 38 controls who received placebo and were matched for age, plasma pyridoxal-5'-phosphate (PLP) concentration and intelligence score. Before and after drug intervention vitamin B-6 status was determined, and mood and performance were measured by means of a computerized testing system. In addition, the phasic pupil response was measured in order to assess mental effort. Positive effects of vitamin B-6 supplementation were only found with respect to memory, especially concerning long-term memory. In view of the finding that mental performance improvement and delta PLP values were most strongly correlated within an intermediate range of delta PLP, it is suggested that cognitive effects are primarily associated with a certain range of vitamin B-6 status increment. The general conclusion is that vitamin B-6 supplementation improves storage of information modestly but significantly.

Residual effects of lormetazepam on mood and performance in healthy elderly volunteers

45 subjects aged over 65 years were randomly assigned to treatment with lormetazepam 0.5 mg or 1 mg or placebo. Mood and performance were measured with a battery of computerized tests. Subjects were tested before and after 1 and 8 nights of treatment. Pre- and post-treatment scores were analysed by a multivariate covariance technique, the pre-treatment score serving as covariate. The single and repeated doses of lormetazepam resulted in impairment of performance in a memory task, and the repeated dose administration impaired performance of a perceptual task. The single administration of a low dose gave an improvement in fine motor control. No change was found in the mood states of the subjects.

Dietary effects on mood and performance

Of 20 young students recruited at a college for nutrition, 10 followed a diet for a period of 3 weeks and 10 were assigned to a control condition. One subject in the control group dropped out. The diet consisted of approximately 70 g protein and 25 g carbohydrate at breakfast and 10 g protein and 100 g carbohydrate at dinner. In between, a protein luncheon was consumed. On the last day of the 3-week period repeated measurements of mood and performance were made, i.e. after breakfast and after dinner. Consequently, the same measurements were made 2 months later to serve as covariates in the analyses to control for base-line differences of the two groups. It was predicted that, in the morning, the performance and the vigour of the diet group would improve whereas, in the evening, performance would become worse and subjects would feel more sleepy. However, the diet group was found to have a higher anger score in the morning (probably due to the unattractive nature of the diet) and a tendency to have a higher fatigue score in the evening compared with the controls. In addition, the diet group performed better in the morning on finger tapping, compared with the control group. With respect to memory scanning, the diet group performed more slowly in the morning in comparison with the control group. From these conflicting results, it was concluded that dietary composition had no effect on mood and behaviour.

Effects of paroxetine and maprotiline on mood, perceptual-motor skills and eye movements in healthy volunteers

Sixteen healthy young volunteers (seven females, nine males) received repeated doses of either 30 mg paroxetine, 100 mg maprotiline or placebo in a double-blind crossover study. Each of the three treatments lasted 1 week separated by 2 weeks of no treatment. Treatment order was counterbalanced. Subjects were tested before each treatment period, and after 1 and 7 days of treatment. Measurements were made of mood, perceptual-motor skills, and eye movements including pupil size when subjects were watching a traffic film.

Task effects and individual differences in the study of lateral eye movements

Twenty-nine males and 29 females (all right-handed) participated in this study. The effects of question type (numerical, verbal, spatial) and experimenter position (in front of or behind the subject) on direction of lateral eye movements (LEMs) were tested. Also the relation between dominant LEM direction and other individual traits was investigated. The percentage of LEMs (tonic changes) as well as the first LEM (phasic changes) in the reflective period was scored. Results were identical for both methods; there were no task-specific effects demonstrated, nor was a relation found between dominant LEM direction and imagery, extraversion, neuroticism, sensation seeking, impulsiveness, and amount of somatic and psychic complaints. It appeared that the extent to which subjects gazed away varied with the amount of stress that was induced, while the direction of glance depended on the individual habit of the subject. The conclusion was that LEMs are subject specific rather than task specific and that this individual specificity is strengthened under stress conditions.

The effects of nicotinic acid and xanthinol nicotinate on human memory in different categories of age. A double blind study

The treatment effect of nicotinic acid and xanthinol nicotinate on human memory was compared with placebo in 96 healthy subjects. Forty-three subjects were young (35-45 years), 30 subjects middle aged (55-65 years) and 23 subjects were old aged (75-85 years). Pre- and post-treatment scores were measured on a battery of memory tasks, covering sensory register, short-term memory and long-term memory. The treatment regime was 1 dragee t.i.d. for 8 weeks. The administration of xanthinol nicotinate (500 mg, containing 141.7 mg nicotinic acid), nicotinic acid (141.7 mg) and placebo (lactose) was double-blind. Pre- and post-treatment scores were analysed by means of a multivariate covariance technique, the pre-treatment score serving as covariate. Nicotinic acid treatment resulted in improvement of sensory register and short-term memory, while xanthinol nicotinate improved sensory register, short-term memory and long-term memory. In comparison with placebo, both active compounds yielded improvements of 10-40%, depending on type of task. Treatment effects of nicotinic acid were predominantly found in the young and middle-aged, whereas treatment effects of xanthinol nicotinate were predominantly found in the old. These results are interpreted by the supposed activity of nicotinic acid at the cell membrane, improving neuronal transmission, and of xanthinol nicotinate inside the cell, enhancing cell metabolism and oxygen supply in the brain.