Cognitive function in healthy older European adults: the ZENITH study

Structured Long-Chain Omega-3 Fatty Acids for Improvement of Cognitive Function during Aging

Although the human lifespan has increased in the past century owing to advances in medicine and lifestyle, the human healthspan has not kept up the same pace, especially in brain aging. Consequently, the role of preventive health interventions has become a crucial strategy, in particular, the identification of nutritional compounds that could alleviate the deleterious effects of aging. Among nutrients to cope with aging in special cognitive decline, the long-chain omega-3 polyunsaturated fatty acids (ω-3 LCPUFAs) docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), have emerged as very promising ones. Due to their neuroinflammatory resolving effects, an increased status of DHA and EPA in the elderly has been linked to better cognitive function and a lower risk of dementia. However, the results from clinical studies do not show consistent evidence and intake recommendations for old adults are lacking. Recently, supplementation with structured forms of EPA and DHA, which can be derived natural forms or targeted structures, have proven enhanced bioavailability and powerful benefits. This review summarizes present and future perspectives of new structures of ω-3 LCPUFAs and the role of "omic" technologies combined with the use of high-throughput in vivo models to shed light on the relationships and underlying mechanisms between ω-3 LCPUFAs and healthy aging.

Falls and Cognitive Training 2 (FaCT2) study protocol: a randomised controlled trial exploring cognitive training to reduce risk of falls in at-risk older adults

BACKGROUND

The primary cause of traumatic injury in older adults is fall. Recent reports suggest that cognitive function contributes significantly to fall risk. Therefore, by targeting cognitive function for intervention, we could potentially reduce the incidence of fall and injury.

PRIMARY OBJECTIVE

To explore the effectiveness of a 16-week cognitive training (CT) intervention to reduce risk and incidence of fall in community-dwelling older adults at risk for fall.

OUTCOMES

Primary outcome is number of falls over a 16-week period (ascertained by fall calendar method). Secondary outcomes include: change fall risk as indicated by improvement in 10 m walk and 90 s balance tests.

DESIGN/METHODS

The design is a two-group randomised controlled trial. Eligible participants are older adults (aged 65-85) residing in the community who are at risk for fall based on physical performance testing. Following completion of 1-week run-in phase, participants are randomly allocated (1:2) to either a group that is assigned to attention control or to the group that receives CT intervention for a total of 16 weeks. Participants are followed for an additional 4 weeks after intervention. Mann-Whitney U test and Student's t-test will be used to examine between-group differences using intention-to-treat analyses.

DISCUSSION

Limited evidence supports the potential of CT to improve cognition and gait, but no published study has evaluated whether such an intervention would reduce incidence of fall. The present trial is designed to provide initial answers to this question. CT may also improve functioning important in other activities (eg, driving), reducing overall risk of injury in elders.

TRIAL REGISTRATION NUMBER

NCT03190460.

Consumption of a soy drink has no effect on cognitive function but may alleviate vasomotor symptoms in post-menopausal women; a randomised trial

PURPOSE

Cognitive decline is commonly reported during the menopausal transition, with memory and attention being particularly affected. The aim of this study was to investigate the effects of a commercially available soy drink on cognitive function and menopausal symptoms in post-menopausal women.

METHODS

101 post-menopausal women, aged 44-63 years, were randomly assigned to consume a volume of soy drink providing a low (10 mg/day; control group), medium (35 mg/day), or high (60 mg/day) dose of isoflavones for 12 weeks. Cognitive function (spatial working memory, spatial span, pattern recognition memory, 5-choice reaction time, and match to sample visual search) was assessed using CANTAB pre- and post-the 12 week intervention. Menopausal symptoms were assessed using Greene's Climacteric Scale.

RESULTS

No significant differences were observed between the groups for any of the cognitive function outcomes measured. Soy drink consumption had no effect on menopausal symptoms overall; however, when women were stratified according to the severity of vasomotor symptoms (VMS) at baseline, women with more severe symptoms at baseline in the medium group had a significant reduction (P = 0.001) in VMS post-intervention (mean change from baseline score: - 2.15 ± 1.73) in comparison to those with less severe VMS (mean change from baseline score: 0.06 ± 1.21).

CONCLUSIONS

Soy drink consumption had no effect on cognitive function in post-menopausal women. Consumption of ~ 350 ml/day (35 mg IFs) for 12 weeks significantly reduced VMS in those with more severe symptoms at baseline. This finding is clinically relevant as soy drinks may provide an alternative, natural, treatment for alleviating VMS, highly prevalent among western women.

Vitamin and mineral supplementation for maintaining cognitive function in cognitively healthy people in mid and late life

BACKGROUND

Vitamins and minerals play multiple functions within the central nervous system which may help to maintain brain health and optimal cognitive functioning. Supplementation of the diet with various vitamins and minerals has been suggested as a means of maintaining cognitive function, or even of preventing dementia, in later life.

OBJECTIVES

To evaluate the effects of vitamin and mineral supplementation on cognitive function in cognitively healthy people aged 40 years or more.

SEARCH METHODS

We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Group's (CDCIG) specialised register, as well as MEDLINE, Embase, PsycINFO, CINAHL, ClinicalTrials.gov and the WHO Portal/ICTRP from inception to 26th January 2018.

SELECTION CRITERIA

We included randomised controlled trials that evaluated the cognitive effects on people aged 40 years or more of any vitamin or mineral supplements taken by mouth for at least three months.

DATA COLLECTION AND ANALYSIS

Study selection, data extraction, and quality assessments were done in duplicate. Vitamins were considered broadly in the categories of B vitamins, antioxidant vitamins, and combinations of both. Minerals were considered separately, where possible. If interventions and outcomes were considered sufficiently similar, then data were pooled. In order to separate short-term cognitive effects from possible longer-term effects on the trajectory of cognitive decline, data were pooled for various treatment durations from 3 months to 12 months and up to 10 years or more.

MAIN RESULTS

In total, we included 28 studies with more than 83,000 participants. There were some general limitations of the evidence. Most participants were enrolled in studies which were not designed primarily to assess cognition. These studies often had no baseline cognitive assessment and used only brief cognitive assessments at follow-up. Very few studies assessed the incidence of dementia. Most study reports did not mention adverse events or made only very general statements about them. Only 10 studies had a mean follow-up > 5 years. Only two studies had participants whose mean age was < 60 years at baseline. The risk of bias in the included studies was generally low, other than a risk of attrition bias for longer-term outcomes. We considered the certainty of the evidence behind almost all results to be moderate or low.We included 14 studies with 27,882 participants which compared folic acid, vitamin B12, vitamin B6, or a combination of these to placebo. The majority of participants were aged over 60 years and had a history of cardio- or cerebrovascular disease. We found that giving B vitamin supplements to cognitively healthy adults, mainly in their 60s and 70s, probably has little or no effect on global cognitive function at any time point up to 5 years (SMD values from -0.03 to 0.06) and may also have no effect at 5-10 years (SMD -0.01). There were very sparse data on adverse effects or on incidence of cognitive impairment or dementia.We included 8 studies with 47,840 participants in which the active intervention was one or more of the antioxidant vitamins: ß-carotene, vitamin C or vitamin E. Results were mixed. For overall cognitive function, there was low-certainty evidence of benefit associated with ß-carotene after a mean of 18 years of treatment (MD 0.18 TICS points, 95% CI 0.01 to 0.35) and of vitamin C after 5 years to 10 years (MD 0.46 TICS points, 95% CI 0.14 to 0.78), but not at earlier time points. From two studies which reported on dementia incidence, there was low-certainty evidence of no effect of an antioxidant vitamin combination or of vitamin E, either alone or combined with selenium. One of the included studies had been designed to look for effects on the incidence of prostate cancer; it found a statistically significant increase in prostate cancer diagnoses among men taking vitamin E.One trial with 4143 participants compared vitamin D3 (400 IU/day) and calcium supplements to placebo. We found low- to moderate-certainty evidence of no effect of vitamin D3 and calcium supplements at any time-point up to 10 years on overall cognitive function (MD after a mean of 7.8 years -0.1 MMSE points, 95% CI -0.81 to 0.61) or the incidence of dementia (HR 0.94, 95% CI 0.72 to 1.24). A pilot study with 60 participants used a higher dose of vitamin D3 (4000 IU on alternate days) and found preliminary evidence that this dose probably has no effect on cognitive function over six months.We included data from one trial of zinc and copper supplementation with 1072 participants. There was moderate-certainty evidence of little or no effect on overall cognitive function (MD 0.6 MMSE points, 95% CI -0.19 to 1.39) or on the incidence of cognitive impairment after 5 years to 10 years. A second smaller trial provided no usable data, but reported no cognitive effects of six months of supplementation with zinc gluconate.From one study with 3711 participants, there was low-certainty evidence of no effect of approximately five years of selenium supplementation on the incidence of dementia (HR 0.83, 95% CI 0.61 to 1.13).Finally, we included three trials of complex supplements (combinations of B vitamins, antioxidant vitamins, and minerals) with 6306 participants. From the one trial which assessed overall cognitive function, there was low-certainty evidence of little or no effect on the TICS (MD after a mean of 8.5 years 0.12, 95% CI -0.14 to 0.38).

AUTHORS' CONCLUSIONS

We did not find evidence that any vitamin or mineral supplementation strategy for cognitively healthy adults in mid or late life has a meaningful effect on cognitive decline or dementia, although the evidence does not permit definitive conclusions. There were very few data on supplementation starting in midlife (< 60 years); studies designed to assess cognitive outcomes tended to be too short to assess maintenance of cognitive function; longer studies often had other primary outcomes and used cognitive measures which may have lacked sensitivity. The only positive signals of effect came from studies of long-term supplementation with antioxidant vitamins. These may be the most promising for further research.

Vitamin and mineral supplementation for preventing dementia or delaying cognitive decline in people with mild cognitive impairment

BACKGROUND

Vitamins and minerals have many functions in the nervous system which are important for brain health. It has been suggested that various different vitamin and mineral supplements might be useful in maintaining cognitive function and delaying the onset of dementia. In this review, we sought to examine the evidence for this in people who already had mild cognitive impairment (MCI).

OBJECTIVES

To evaluate the effects of vitamin and mineral supplementation on cognitive function and the incidence of dementia in people with mild cognitive impairment.

SEARCH METHODS

We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Group's (CDCIG) specialised register, as well as MEDLINE, Embase, PsycINFO, CENTRAL, CINAHL, LILACs, Web of Science Core Collection, ClinicalTrials.gov, and the WHO Portal/ICTRP, from inception to 25 January 2018.

SELECTION CRITERIA

We included randomised or quasi-randomised, placebo-controlled trials which evaluated orally administered vitamin or mineral supplements in participants with a diagnosis of mild cognitive impairment and which assessed the incidence of dementia or cognitive outcomes, or both. We were interested in studies applicable to the general population of older people and therefore excluded studies in which participants had severe vitamin or mineral deficiencies.

DATA COLLECTION AND ANALYSIS

We sought data on our primary outcomes of dementia incidence and overall cognitive function and on secondary outcomes of episodic memory, executive function, speed of processing, quality of life, functional performance, clinical global impression, adverse events, and mortality. We conducted data collection and analysis according to standard Cochrane systematic review methods. We assessed the risk of bias of included studies using the Cochrane 'Risk of bias' assessment tool. We grouped vitamins and minerals according to their putative mechanism of action and, where we considered it to be clinically appropriate, we pooled data using random-effects methods. We used GRADE methods to assess the overall quality of evidence for each comparison and outcome.

MAIN RESULTS

We included five trials with 879 participants which investigated B vitamin supplements. In four trials, the intervention was a combination of vitamins B6, B12, and folic acid; in one, it was folic acid only. Doses varied. We considered there to be some risks of performance and attrition bias and of selective outcome reporting among these trials. Our primary efficacy outcomes were the incidence of dementia and scores on measures of overall cognitive function. None of the trials reported the incidence of dementia and the evidence on overall cognitive function was of very low-quality. There was probably little or no effect of B vitamins taken for six to 24 months on episodic memory, executive function, speed of processing, or quality of life. The evidence on our other secondary clinical outcomes, including harms, was very sparse or very low-quality. There was evidence from one study that there may be a slower rate of brain atrophy over two years in participants taking B vitamins. The same study reported subgroup analyses based on the level of serum homocysteine (tHcy) at baseline and found evidence that B vitamins may improve episodic memory in those with tHcy above the median at baseline.We included one trial (n = 516) of vitamin E supplementation. Vitamin E was given as 1000 IU of alpha-tocopherol twice daily. We considered this trial to be at risk of attrition and selective reporting bias. There was probably no effect of vitamin E on the probability of progression from MCI to Alzheimer's dementia over three years (HR 1.02; 95% CI 0.74 to 1.41; n = 516; 1 study, moderate-quality evidence). There was also no evidence of an effect at intermediate time points. The available data did not allow us to conduct analyses, but the authors reported no significant effect of three years of supplementation with vitamin E on overall cognitive function, episodic memory, speed of processing, clinical global impression, functional performance, adverse events, or mortality (five deaths in each group). We considered this to be low-quality evidence.We included one trial (n = 256) of combined vitamin E and vitamin C supplementation and one trial (n = 26) of supplementation with chromium picolinate. In both cases, there was a single eligible cognitive outcome, but we considered the evidence to be very low-quality and so could not be sure of any effects.

AUTHORS' CONCLUSIONS

The evidence on vitamin and mineral supplements as treatments for MCI is very limited. Three years of treatment with high-dose vitamin E probably does not reduce the risk of progression to dementia, but we have no data on this outcome for other supplements. Only B vitamins have been assessed in more than one RCT. There is no evidence for beneficial effects on cognition of supplementation with B vitamins for six to 24 months. Evidence from a single study of a reduced rate of brain atrophy in participants taking vitamin B and a beneficial effect of vitamin B on episodic memory in those with higher tHcy at baseline warrants attempted replication.

The Efficacy and Pharmacological Mechanism of Zn7MT3 to Protect against Alzheimer's Disease

Alzheimer’s disease (AD) is one of the leading causes of death for people over 65 years. Worse still, no completely effective therapeutic agent is available so far. One important pathological hallmark of AD is accumulated amyloid-β (Aβ) plaques with dysregulated metal homeostasis. Human metallothionin 3 (MT3), a regulator of metal homeostasis, is downregulated at least 30% in AD brain. So far, some in vitro studies demonstrated its multiple functions related to AD. However, it is a great pity that systematic in vivo studies of MT3 on AD model animals are still a blank so far. In this study, we treated APP/PS1 mice with sustained drug release of Zn₇MT3 directly to the central nervous system, and investigated the role and molecular mechanism of Zn₇MT3 to protect against AD mice systematically. The results demonstrated that Zn₇MT3 can significantly ameliorate cognitive deficits, regulate metal homeostasis, abolish Aβ plaque load, and reduce oxidative stress. Additionally, it has been confirmed that MT3 is penetrable to the blood brain barrier of AD mice. All these results support that Zn₇MT3 is an effective AD suppressing agent and has potential for applications in Alzheimer’s disease therapy.

Help-seeking intentions for early dementia diagnosis in a sample of Irish adults

OBJECTIVES

To identify factors that may increase intentions to seek help for an early dementia diagnosis. Early dementia diagnosis in Ireland is low, reducing the opportunity for intervention, which can delay progression, reduce psychological distress and increase social supports.

METHOD

Using the theory of planned behaviour (TPB), and a mixed methods approach, three focus groups were conducted (N = 22) to illicit attitudes and beliefs about help seeking for an early dementia diagnosis. The findings informed the development of the Help Seeking Intentions for Early Dementia Diagnosis (HSIEDD) questionnaire which was piloted and then administered to a sample of community dwelling adults from Dublin and Kildare (N = 95).

RESULTS

Content analysis revealed participants held knowledge of the symptoms of dementia but not about available interventions. Facilitators of help seeking were family, friends and peers alongside well informed health professionals. Barriers to seeking help were a lack of knowledge, fear, loss, stigma and inaccessible services. The quantitative findings suggest the TPB constructs account for almost 28% of the variance in intentions to seek help for an early diagnosis of dementia, after controlling for sociodemographic variables and knowledge of dementia. In the final step of the regression analysis, the main predictors of help seeking were knowledge of dementia and subjective norm, accounting for 6% and 8% of the variance, respectively.

CONCLUSION

Future interventions should aim to increase awareness of the support available to those experiencing early memory problems, and should highlight the supportive role that family, friends, peers and health professionals could provide.

Influence of schooling and age on cognitive performance in healthy older adults

Few studies have examined the influence of a low level of schooling on age-related cognitive decline in countries with wide social and economic inequalities by using the Cambridge Automated Neuropsychological Test Battery (CANTAB). The aim of the present study was to assess the influence of schooling on age-related cognitive decline using unbiased cognitive tests. CANTAB allows cognitive assessment across cultures and education levels with reduced interference of the examiner during data acquisition. Using two-way ANOVA, we assessed the influences of age and education on test scores of old adults (61–84 years of age). CANTAB tests included: Visual Sustained Attention, Reaction Time, Spatial Working Memory, Learning and Episodic Memory. All subjects had a minimum visual acuity of 20/30 (Snellen Test), no previous or current history of traumatic brain/head trauma, stroke, language impairment, chronic alcoholism, neurological diseases, memory problems or depressive symptoms, and normal scores on the Mini Mental State Examination (MMSE). Subjects were grouped according to education level (1 to 7 and ≥8 years of schooling) and age (60–69 and ≥70 years). Low schooling level was associated with significantly lower performance on visual sustained attention, learning and episodic memory, reaction time, and spatial working memory. Although reaction time was influenced by age, no significant results on post hoc analysis were detected. Our findings showed a significantly worse cognitive performance in volunteers with lower levels of schooling and suggested that formal education in early life must be included in the preventive public health agenda. In addition, we suggest that CANTAB may be useful to detect subtle cognitive changes in healthy aging.

Zinc in Alzheimer's Disease: A Meta-Analysis of Serum, Plasma, and Cerebrospinal Fluid Studies

To evaluate whether zinc levels in serum, plasma, and cerebrospinal fluid are altered in Alzheimer's disease (AD), we performed meta-analyses of 27 studies on the topic published from 1983 to 2014. The subjects' sample obtained by merging studies was a pooled total of 777 AD subjects and 1,728 controls for serum zinc studies, 287 AD subjects and 166 controls for plasma zinc, and of 292 AD subjects and 179 controls for CSF zinc. The main result of this meta-analysis is the very high heterogeneity among the studies either in demographic terms or in methodological approaches. Although we considered these effects in our analyses, the heterogeneity persisted and it has to be taken into account in the interpretation of the results. Our meta-analysis indicated that serum zinc appears significantly decreased in AD patients compared with healthy controls, and this result is confirmed when serum and plasma studies were analyzed together. If we considered the age-matched studies, the meta-analysis carried out on only six studies showed no significant difference in zinc levels between AD and healthy controls (SMD =-0.55, 95% CI (-1.18; 0.09); p = 0.094; I2 = 91%). In the light of these findings, we speculated about the possibility that the decreases observed could indicate a possible dietary zinc deficiency and we suggested that the possible involvement of zinc alterations in AD may have an interplay with copper metabolism.

Effects of socio-demographic variables on performance on the Cambridge neuropsychological automated tests for the assessment of dementia and Portuguese norms for older adults living in retirement homes

OBJECTIVE

This study aimed to analyze the effects of age, education, gender, computer experience, institutionalization time, and psychotropic drug use on performance on four tests of the Cambridge Neuropsychological Test Automated Battery (CANTAB) which are recommended for the assessment of dementia (Rapid Visual Information Processing [RVP], Paired Associates Learning [PAL], Spatial Working Memory [SWM], and Reaction Time [RTI]), and to provide norms for Portuguese older persons without neuropsychiatric diagnoses who are living in retirement homes.

METHOD

The normative sample included 128 adults aged 69-96 years who had no neuropsychiatric diagnosis and who had lived in retirement homes for 3-232 months. The CANTAB was administered, at the latest, one week after a screening session that comprised an interview and the administration of pencil-and-paper tests.

RESULTS

The simultaneous multiple linear regression models were significant (p < .05) for all tests except the RTI five-choice movement time measure. The total variance explained by the socio-demographic variables was smaller for the CANTAB measures (4-14%) than for the pencil-and-paper tests (10-33%). Significant effects involving age or gender were observed for RVP, PAL, and SWM. A marginally significant computer experience effect was found for the RTI simple movement time measure. We additionally observed significant effects of education, age, gender, and computer experience on several pencil-and-paper tests.

CONCLUSIONS

Our findings suggest that different socio-demographic variables influence distinct tests and measures of the same test, and that the associations between computer experience and several pencil-and-paper tests may be mediated by possible cognitive skills developed through computer use.

CANTAB object recognition and language tests to detect aging cognitive decline: an exploratory comparative study

Objective

The recognition of the limits between normal and pathological aging is essential to start preventive actions. The aim of this paper is to compare the Cambridge Neuropsychological Test Automated Battery (CANTAB) and language tests to distinguish subtle differences in cognitive performances in two different age groups, namely young adults and elderly cognitively normal subjects.

Method

We selected 29 young adults (29.9±1.06 years) and 31 older adults (74.1±1.15 years) matched by educational level (years of schooling). All subjects underwent a general assessment and a battery of neuropsychological tests, including the Mini Mental State Examination, visuospatial learning, and memory tasks from CANTAB and language tests. Cluster and discriminant analysis were applied to all neuropsychological test results to distinguish possible subgroups inside each age group.

Results

Significant differences in the performance of aged and young adults were detected in both language and visuospatial memory tests. Intragroup cluster and discriminant analysis revealed that CANTAB, as compared to language tests, was able to detect subtle but significant differences between the subjects.

Conclusion

Based on these findings, we concluded that, as compared to language tests, large-scale application of automated visuospatial tests to assess learning and memory might increase our ability to discern the limits between normal and pathological aging.

Intracellular cytokine production and cognition in healthy older adults

Elevated concentrations of the pro-inflammatory cytokines IL-1β and IL-6 have been associated with impaired cognitive performance. There are, however, few studies that have examined the relationship between cytokine production and specific aspects of cognition in healthy older individuals. Two-colour flow cytometry was used to determine intracellular cytokine production by activated monocytes, and neuropsychological tests were performed using the Cambridge Neuropsychological Test Automated Battery (CANTAB) in 93 apparently healthy men and women aged 55-70 years. A series of hierarchical regression analyses was carried out to examine the contribution of IL-1β and IL-6 (% expression and production (antibody binding capacity (ABC))) to recognition, attention and working memory, after controlling for socio-demographic variables (age, sex and social class). IL-1β% expression and IL-6 production predicted aspects of working memory. Recognition memory was found to be sensitive to the affects of age and social class. The current study suggests that higher intracellular cytokine production by activated monocytes may be predictive of lower cognitive performance in working memory in healthy older individuals. These findings indicate that utilization of models for in vivo cytokine production upon immune challenge may be useful in studying specific aspects of memory affected during inflammatory responses, for example in individuals at risk for cognitive decline owing to age-related inflammatory disorders.

Zinc diet and Alzheimer's disease: a systematic review

OBJECTIVES

This paper reviews evidence of an association between zinc (Zn) nutrition and Alzheimer's disease (AD) or age-associated cognitive decline. The involvement of zinc in the pathology of AD has been reported hundreds of times. It is, however, still a matter of debate whether the disease progression can be influenced by modifying zinc in the diet.

METHODS

We searched Medline, Embase, Biosis, ALOIS, the Cochrane central register of controlled trials, the Cochrane database of systematic reviews, and different publisher databases, and included studies that dealt with zinc in the diet and AD or cognitive decline in elderly subjects.

RESULTS

Fifty-five studies met the inclusion criteria. Neither randomized-controlled trials nor observational studies provide conclusive evidence whether Zn in the diet is associated with cognitive decline or AD. Case-control and autopsy studies suggest decreased systemic and increased brain Zn levels, respectively.

DISCUSSION

The current state of evidence does not allow conclusions to be drawn on whether supplementation of Zn is beneficial for the prevention or treatment of AD, although a subclinical deficiency appears common in the elderly and subjects with AD. Dietary studies with animals suggest that the impact of dietary Zn on cognitive performance depend on additional nutrients. Further studies are necessary to determine whether Zn deficiency is a risk factor for AD in general terms or under certain dietary circumstances only.

Zinc status, psychological and nutritional assessment in old people recruited in five European countries: Zincage study

The paper shows the results on the relationship between zinc status, psychological dimensions (cognitive functions, mood, perceived stress) and nutritional aspects in European healthy old subjects recruited for ZINCAGE Project (supported by the European Commission in the Sixth Framework Programme). The old healthy subjects were recruited in Italy, Greece, Germany, France, Poland taking into account the different dietary habits between Northern and Southern European Countries and the pivotal role played by zinc for psychological functions. Measures of the cognitive status, mood and perceived stress level were obtained at baseline, using the "Mini Mental State Examination (MMSE)"; the "Geriatric Depression Scale (GDS - 15 items)" and the "Perceived Stress Scale (PSS)", respectively. Nutritional status was assessed using "Frequency Food Questionnaire". The sample included 853 old subjects, classified in 4 groups of age: 60-69-years-old (n = 359); 70-74-years-old (n = 225); 75-79-years-old (n = 153); 80-84-years-old (n = 116). Subjects were studied on the basis of plasma zinc, in which zinc </=11 microM means marginal zinc deficiency. The total samples showed that the 82% had no cognitive decline, whereas 76% presented a low GDS value indicating no depression. However, all psychological variables were related to plasma zinc values and nutritional assessment. In particular, a relationship between marginal zinc deficiency and impaired psychological dimensions occurred in Greece than in other European countries due to low intake and less variety of foods rich of zinc. This phenomenon was independent by the age, suggesting that a correct zinc intake from a wide range of foods may be useful to maintain a satisfactory plasma zinc levels as well as psychological status in elderly with subsequent achievement of healthy ageing.

Introduction to the ZENITH study and summary of baseline results

Zinc is known to be essential for a great number of biochemical activities and physiological and cognitive functions. The objective of Zenith study was to investigate the effects of Zn, as a nutritional supplement, on psychological and behavioural factors and on surrogate markers that are indicative of trends towards better health in order to evaluate the need for dietary recommendations specific to the studied population. We report in this paper the summary of baseline results obtained before Zn supplementation.