Sofi F, Abbate R, Gensini GF, Casini A.

Department of Medical and Surgical Critical Care, Thrombosis Centre, University of Florence, Florence, Italy. francescosofi@gmail.com

Abstract
BACKGROUND: The Mediterranean diet has long been reported to be protective against the occurrence of several different health outcomes.

OBJECTIVE: We aimed to update our previous meta-analysis of published cohort prospective studies that investigated the effects of adherence to the Mediterranean diet on health status.

DESIGN: We conducted a comprehensive literature search through electronic databases up to June 2010.

RESULTS: The updated review process showed 7 prospective studies published in the past 2 y that were not included in the previous meta-analysis (1 study for overall mortality, 3 studies for cardiovascular incidence or mortality, 1 study for cancer incidence or mortality, and 2 studies for neurodegenerative diseases). These recent studies included 2 health outcomes not previously investigated (ie, mild cognitive impairment and stroke). The meta-analysis for all studies with a random-effects model that was conducted after the inclusion of these recent studies showed that a 2-point increase in adherence to the Mediterranean diet was associated with a significant reduction of overall mortality [relative risk (RR) = 0.92; 95% CI: 0.90, 0.94], cardiovascular incidence or mortality (RR = 0.90; 95% CI: 0.87, 0.93), cancer incidence or mortality (RR = 0.94; 95% CI: 0.92, 0.96), and neurodegenerative diseases (RR = 0.87; 95% CI: 0.81, 0.94). The meta-regression analysis showed that sample size was the most significant contributor to the model because it significantly influenced the estimate of the association for overall mortality.

CONCLUSION: This updated meta-analysis confirms, in a larger number of subjects and studies, the significant and consistent protection provided by adherence to the Mediterranean diet in relation to the occurrence of major chronic degenerative diseases.

PMID: 20810976 [PubMed - indexed for MEDLINE]

Volkow ND, Tomasi D, Wang GJ, Vaska P, Fowler JS, Telang F, Alexoff D, Logan J, Wong C.

National Institute on Drug Abuse, 6001 Executive Blvd, Room 5274, Bethesda, MD 20892, USA. nvolkow@nida.nih.gov

Abstract

CONTEXT: The dramatic increase in use of cellular telephones has generated concern about possible negative effects of radiofrequency signals delivered to the brain. However, whether acute cell phone exposure affects the human brain is unclear.

OBJECTIVE: To evaluate if acute cell phone exposure affects brain glucose metabolism, a marker of brain activity.

DESIGN, SETTING, AND PARTICIPANTS: Randomized crossover study conducted between January 1 and December 31, 2009, at a single US laboratory among 47 healthy participants recruited from the community. Cell phones were placed on the left and right ears and positron emission tomography with ((18)F)fluorodeoxyglucose injection was used to measure brain glucose metabolism twice, once with the right cell phone activated (sound muted) for 50 minutes (“on” condition) and once with both cell phones deactivated (“off” condition). Statistical parametric mapping was used to compare metabolism between on and off conditions using paired t tests, and Pearson linear correlations were used to verify the association of metabolism and estimated amplitude of radiofrequency-modulated electromagnetic waves emitted by the cell phone. Clusters with at least 1000 voxels (volume >8 cm(3)) and P < .05 (corrected for multiple comparisons) were considered significant.

MAIN OUTCOME MEASURE: Brain glucose metabolism computed as absolute metabolism (µmol/100 g per minute) and as normalized metabolism (region/whole brain).

RESULTS: Whole-brain metabolism did not differ between on and off conditions. In contrast, metabolism in the region closest to the antenna (orbitofrontal cortex and temporal pole) was significantly higher for on than off conditions (35.7 vs 33.3 µmol/100 g per minute; mean difference, 2.4 [95% confidence interval, 0.67-4.2]; P = .004). The increases were significantly correlated with the estimated electromagnetic field amplitudes both for absolute metabolism (R = 0.95, P < .001) and normalized metabolism (R = 0.89; P < .001).

CONCLUSIONS: In healthy participants and compared with no exposure, 50-minute cell phone exposure was associated with increased brain glucose metabolism in the region closest to the antenna. This finding is of unknown clinical significance.

PMID: 21343580 [PubMed - indexed for MEDLINE]

Martin M, Clare L, Altgassen AM, Cameron MH, Zehnder F.
Psychologisches Institut, Universität Zürich, Lehrstuhl Gerontopsychologie, Binzmühlestrasse 14/24, Zürich, Switzerland, CH-8050.
Abstract
BACKGROUND: Evidence from some, but not all non-randomised studies suggest the possibility that cognitive training may influence cognitive functioning in older people. Due to the differences among cognitive training interventions reported in the literature, giving a general overview of the current literature remains difficult.
OBJECTIVES: To systematically review the literature and summarize the effect of cognitive training interventions on various domains of cognitive function (ie memory, executive function, attention and speed) in healthy older people and in people with mild cognitive impairment.
SEARCH STRATEGY: The CDCIG Specialized Register was searched on 30 September 2007 for all years up to December 2005. The Cochrane Library, MEDLINE, EMBASE, PsycINFO and CINAHL were searched separately on 30 September 2007 to find trials with healthy people. These results were supplemented by searches from January 1970 to September 2007 in PsychInfo/Psyndex, ISI Web of Knowledge and PubMed.
SELECTION CRITERIA: RCTs of interventions evaluating the effectiveness of cognitive training for healthy older people and people with mild cognitive impairment from 1970 to 2007 that met inclusion criteria were selected.
DATA COLLECTION AND ANALYSIS: Authors independently extracted data and assessed trial quality. Meta-analysis was performed when appropriate.
MAIN RESULTS: Only data on memory training could be pooled for analysis. Within this domain, training interventions were grouped according to several outcome variables. Results showed that for healthy older adults, immediate and delayed verbal recall improved significantly through training compared to a no-treatment control condition. We did not find any specific memory training effects though as the improvements observed did not exceed the improvement in the active control condition. For individuals with mild cognitive impairment, our analyses demonstrate the same pattern. Thus, there is currently little evidence on the effectiveness and specificity of memory interventions for healthy older adults and individuals with mild cognitive impairment.
AUTHORS’ CONCLUSIONS: There is evidence that cognitive interventions do lead to performance gains but none of the effects observed could be attributable specifically to cognitive training, as the improvements observed did not exceed the improvement in active control conditions. This does not mean that longer, more intense or different interventions might not be effective, but that those which have been reported thus far have only limited effect. We therefore suggest more standardized study protocols in order to maximize comparability of studies and to maximize the possibility of data pooling – also in other cognitive domains than memory.

Lin J, Fung TT, Hu FB, Curhan GC.
Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA. jlin11@partners.org
Abstract
BACKGROUND: Dietary patterns have been linked to such chronic diseases as cardiovascular disease, but sparse data currently are available for associations between dietary patterns and microalbuminuria or kidney function decline.
STUDY DESIGN: Subgroup analysis from a prospective observational cohort study.
SETTING & PARTICIPANTS: Female participants in the Nurses’ Health Study who had dietary pattern data from food frequency questionnaires returned in 1984, 1986, 1990, 1994, and 1998 and urinary albumin-creatinine ratios from 2000 (n = 3,121); estimated glomerular filtration rate (eGFR) change between 1989 and 2000 was available for 3,071.
PREDICTOR: Prudent (higher intake of fruits, vegetables, legumes, fish, poultry, and whole grains), Western (higher intake of red and processed meats, saturated fats, and sweets), and Dietary Approach to Stop Hypertension (DASH)-style dietary patterns (also greater intake of vegetables, fruits, and whole grains).
OUTCOMES & MEASUREMENTS: Microalbuminuria (albumin-creatinine ratio, 25-354 µg/mg) in 2000 and change in kidney function using eGFR between 1989 and 2000.
RESULTS: After multivariable adjustment, the highest quartile of Western pattern score compared with the lowest quartile was associated directly with microalbuminuria (OR, 2.17; 95% CI, 1.18-3.66; P for trend = 0.01) and rapid eGFR decline =3 mL/min/1.73 m(2)/y (OR, 1.77; 95% CI, 1.03-3.03). Women in the top quartile of the DASH score had decreased risk of rapid eGFR decline (OR, 0.55; 95% CI, 0.38-0.80), but no association with microalbuminuria. These associations did not vary by diabetes status. The prudent dietary pattern was not associated with microalbuminuria or eGFR decline.
LIMITATIONS: Study cohort included primarily older white women and generalizability of results would benefit from validation in nonwhites and men.
CONCLUSIONS: A Western dietary pattern is associated with a significantly increased odds of microalbuminuria and rapid kidney function decrease, whereas a DASH-style dietary pattern may be protective against rapid eGFR decline.

Thompson Coon J, Boddy K, Stein K, Whear R, Barton J, Depledge MH.
PenCLAHRC, Peninsula College of Medicine and Dentistry, University of Exeter , Veysey Building, Salmon Pool Lane, Exeter EX2 4SG, United Kingdom.
Abstract
Our objective was to compare the effects on mental and physical wellbeing, health related quality of life and long-term adherence to physical activity, of participation in physical activity in natural environments compared with physical activity indoors. We conducted a systematic review using the following data sources: Medline, Embase, Psychinfo, GreenFILE, SportDISCUS, The Cochrane Library, Science Citation Index Expanded, Social Sciences Citation Index, Arts and Humanities Citation Index, Conference Proceedings Citation Index – Science and BIOSIS from inception to June 2010. Internet searches of relevant Web sites, hand searches of relevant journals, and the reference lists of included papers and other review papers identified in the search were also searched for relevant information. Controlled trials (randomized and nonrandomized) were included. To be eligible trials had to compare the effects of outdoor exercise initiatives with those conducted indoors and report on at least one physical or mental wellbeing outcome in adults or children. Screening of articles for inclusion, data extraction, and quality appraisal were performed by one reviewer and checked by a second with discrepancies resolved by discussion with a third if necessary. Due to the heterogeneity of identified studies a narrative synthesis was performed. Eleven trials (833 adults) were included. Most participants (6 trials; 523 adults) were young students. Study entry criteria and methods were sparsely reported. All interventions consisted of a single episode of walking or running indoors with the same activity at a similar level conducted outdoors on a separate occasion. A total of 13 different outcome measures were used to evaluate the effects of exercise on mental wellbeing, and 4 outcome measures were used to assess attitude to exercise. Most trials (n = 9) showed some improvement in mental wellbeing on one or other of the outcome measures. Compared with exercising indoors, exercising in natural environments was associated with greater feelings of revitalization and positive engagement, decreases in tension, confusion, anger, and depression, and increased energy. However, the results suggested that feelings of calmness may be decreased following outdoor exercise. Participants reported greater enjoyment and satisfaction with outdoor activity and declared a greater intent to repeat the activity at a later date. None of the identified studies measured the effects of physical activity on physical wellbeing or the effect of natural environments on exercise adherence. The hypothesis that there are added beneficial effects to be gained from performing physical activity outdoors in natural environments is very appealing and has generated considerable interest. This review has shown some promising effects on self-reported mental wellbeing immediately following exercise in nature which are not seen following the same exercise indoors. However, the interpretation and extrapolation of these findings is hampered by the poor methodological quality of the available evidence and the heterogeneity of outcome measures employed. The review demonstrates the paucity of high quality evidence on which to base recommendations and reveals an undoubted need for further research in this area. Large, well designed, longer term trials in populations who might benefit most from the potential advantages of outdoor exercise are needed to fully elucidate the effects on mental and physical wellbeing. The influence of these effects on the sustainability of physical activity initiatives also awaits investigation.

Cassidy A , O’Reilly EJ , Kay C , Sampson L , Franz M , Forman J , Curhan G , Rimm EB .

School of Medicine, University of East Anglia, Norwich, United Kingdom and Renal Division, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA.

BACKGROUND: Dietary flavonoids have beneficial effects on blood pressure in intervention settings, but there is limited information on habitual intake and risk of hypertension in population-based studies.

OBJECTIVE: We examined the association between habitual flavonoid intake and incident hypertension in a prospective study in men and women.

DESIGN: A total of 87,242 women from the Nurses’ Health Study (NHS) II, 46,672 women from the NHS I, and 23,043 men from the Health Professionals Follow-Up Study (HPFS) participated in the study. Total flavonoid and subclass intakes were calculated from semiquantitative food-frequency questionnaires collected every 4 y by using an updated and extended US Department of Agriculture database.

RESULTS: During 14 y of follow-up, 29,018 cases of hypertension in women and 5629 cases of hypertension in men were reported. In pooled multivariate-adjusted analyses, participants in the highest quintile of anthocyanin intake (predominantly from blueberries and strawberries) had an 8% reduction in risk of hypertension [relative risk (RR): 0.92; 95% CI: 0.86, 0.98; P < 0.03] compared with that for participants in the lowest quintile of anthocyanin intake; the risk reduction was 12% (RR: 0.88; 95% CI: 0.84, 0.93; P < 0.001) in participants =60 y of age and 0.96 (0.91, 1.02) in participants >60 y of age (P for age interaction = 0.02). Although intakes of other subclasses were not associated with hypertension, pooled analyses for individual compounds suggested a 5% (95% CI: 0.91, 0.99; P = 0.005) reduction in risk for the highest compared with the lowest quintiles of intake of the flavone apigenin. In participants =60 y of age, a 6% (95% CI: 0.88, 0.97; P = 0.002) reduction in risk was observed for the flavan-3-ol catechin when the highest and the lowest quintiles were compared.

CONCLUSIONS: Anthocyanins and some flavone and flavan-3-ol compounds may contribute to the prevention of hypertension. These vasodilatory properties may result from specific structural similarities (including the B-ring hydroxylation and methyoxylation pattern).

PMCID: PMC3021426 [Available on 2012/2/1]
PMID: 21106916 [PubMed - in process]