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Nutricion Hospitalaria Jan 2018Malnutrition in children with cancer is a significant risk factor for negative outcomes, but in the clinical practice setting, it is difficult to pinpoint which factors... (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
Malnutrition in children with cancer is a significant risk factor for negative outcomes, but in the clinical practice setting, it is difficult to pinpoint which factors operate to cause substantial weight loss and malnutrition in a given patient. Appetite-related hormones like ghrelin and leptin are among possible mediators. However, only few studies have examined the role of these hormones in pediatric patients with cancer to date. Thus, the purpose of this study was to systematically review possible changes in the levels of appetite hormones, specially leptin and ghrelin, in pediatric patients with cancer.
MATERIAL AND METHODS
We systematically reviewed the literature using PubMed, Lilacs and Scielo, as well as manual bibliographical reference search of the studies. According to the Medical Subject Headings of the National Library of Medicine (MeSH), "childhood cancer", "ghrelin" and "leptin" were used as descriptors.
RESULTS
Fifteen studies were included in this systematic review published in English, from 2000 to 2015. A total of 863 patients were evaluated, ages ranging from 0 to 21 years, and most of the studies reported on children and adolescents with acute lymphoblastic leukemia (ALL) survivors. Most studies analyzed leptin levels; only two studies evaluated levels of ghrelin.
CONCLUSION
This review confirms that changes in the responses of the ghrelin and leptin hormones in children and adolescents with cancer are quite diverse, probably due to the different types of cancer observed, different treatments performed and biological characteristics of this age group.
Topics: Adolescent; Appetite Regulation; Child; Ghrelin; Hormones; Humans; Leptin; Neoplasms; Observational Studies as Topic
PubMed: 29565170
DOI: 10.20960/nh.1221 -
The Cochrane Database of Systematic... Aug 2017There is evidence from observational studies that whole grains can have a beneficial effect on risk for cardiovascular disease (CVD). Earlier versions of this review... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
There is evidence from observational studies that whole grains can have a beneficial effect on risk for cardiovascular disease (CVD). Earlier versions of this review found mainly short-term intervention studies. There are now longer-term randomised controlled trials (RCTs) available. This is an update and expansion of the original review conducted in 2007.
OBJECTIVES
The aim of this systematic review was to assess the effect of whole grain foods or diets on total mortality, cardiovascular events, and cardiovascular risk factors (blood lipids, blood pressure) in healthy people or people who have established cardiovascular disease or related risk factors, using all eligible RCTs.
SEARCH METHODS
We searched CENTRAL (Issue 8, 2016) in the Cochrane Library, MEDLINE (1946 to 31 August 2016), Embase (1980 to week 35 2016), and CINAHL Plus (1937 to 31 August 2016) on 31 August 2016. We also searched ClinicalTrials.gov on 5 July 2017 and the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) on 6 July 2017. We checked reference lists of relevant articles and applied no language restrictions.
SELECTION CRITERIA
We selected RCTs assessing the effects of whole grain foods or diets containing whole grains compared to foods or diets with a similar composition, over a minimum of 12 weeks, on cardiovascular disease and related risk factors. Eligible for inclusion were healthy adults, those at increased risk of CVD, or those previously diagnosed with CVD.
DATA COLLECTION AND ANALYSIS
Two review authors independently selected studies. Data were extracted and quality-checked by one review author and checked by a second review author. A second review author checked the analyses. We assessed treatment effect using mean difference in a fixed-effect model and heterogeneity using the I statistic and the Chi test of heterogeneity. We assessed the overall quality of evidence using GRADE with GRADEpro software.
MAIN RESULTS
We included nine RCTs randomising a total of 1414 participants (age range 24 to 70; mean age 45 to 59, where reported) to whole grain versus lower whole grain or refined grain control groups. We found no studies that reported the effect of whole grain diets on total cardiovascular mortality or cardiovascular events (total myocardial infarction, unstable angina, coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, total stroke). All included studies reported the effect of whole grain diets on risk factors for cardiovascular disease including blood lipids and blood pressure. All studies were in primary prevention populations and had an unclear or high risk of bias, and no studies had an intervention duration greater than 16 weeks.Overall, we found no difference between whole grain and control groups for total cholesterol (mean difference 0.07, 95% confidence interval -0.07 to 0.21; 6 studies (7 comparisons); 722 participants; low-quality evidence).Using GRADE, we assessed the overall quality of the available evidence on cholesterol as low. Four studies were funded by independent national and government funding bodies, while the remaining studies reported funding or partial funding by organisations with commercial interests in cereals.
AUTHORS' CONCLUSIONS
There is insufficient evidence from RCTs of an effect of whole grain diets on cardiovascular outcomes or on major CVD risk factors such as blood lipids and blood pressure. Trials were at unclear or high risk of bias with small sample sizes and relatively short-term interventions, and the overall quality of the evidence was low. There is a need for well-designed, adequately powered RCTs with longer durations assessing cardiovascular events as well as cardiovascular risk factors.
Topics: Adult; Aged; Cardiovascular Diseases; Cholesterol; Cholesterol, HDL; Cholesterol, LDL; Coronary Disease; Edible Grain; Humans; Middle Aged; Randomized Controlled Trials as Topic; Risk Factors; Triglycerides
PubMed: 28836672
DOI: 10.1002/14651858.CD005051.pub3 -
The Cochrane Database of Systematic... Jul 2017The glycaemic index (GI) is a physiological measure of the ability of a carbohydrate to affect blood glucose. Interest is growing in this area for the clinical... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The glycaemic index (GI) is a physiological measure of the ability of a carbohydrate to affect blood glucose. Interest is growing in this area for the clinical management of people at risk of, or with, established cardiovascular disease. There is a need to review the current evidence from randomised controlled trials (RCTs) in this area. This is an update of the original review published in 2008.
OBJECTIVES
To assess the effect of the dietary GI on total mortality, cardiovascular events, and cardiovascular risk factors (blood lipids, blood pressure) in healthy people or people who have established cardiovascular disease or related risk factors, using all eligible randomised controlled trials.
SEARCH METHODS
We searched CENTRAL, MEDLINE, Embase and CINAHL in July 2016. We also checked reference lists of relevant articles. No language restrictions were applied.
SELECTION CRITERIA
We selected RCTs that assessed the effects of low GI diets compared to diets with a similar composition but a higher GI on cardiovascular disease and related risk factors. Minimum trial duration was 12 weeks. Participants included were healthy adults or those at increased risk of cardiovascular disease, or previously diagnosed with cardiovascular disease. Studies in people with diabetes mellitus were excluded.
DATA COLLECTION AND ANALYSIS
Two reviewers independently screened and selected studies. Two review authors independently assessed risk of bias, evaluated the overall quality of the evidence using GRADE, and extracted data following the Cochrane Handbook for Systematic Reviews of Interventions. We contacted trial authors for additional information. Analyses were checked by a second reviewer. Continuous outcomes were synthesized using mean differences and adverse events were synthesized narratively.
MAIN RESULTS
Twenty-one RCTs were included, with a total of 2538 participants randomised to low GI intervention (1288) or high GI (1250). All 21 included studies reported the effect of low GI diets on risk factors for cardiovascular disease, including blood lipids and blood pressure.Twenty RCTs (18 of which were newly included in this version of the review) included primary prevention populations (healthy individuals or those at high risk of CVD, with mean age range from 19 to 69 years) and one RCT was in those diagnosed with pre-existing CVD (a secondary prevention population, with mean age 26.9 years). Most of the studies did not have an intervention duration of longer than six months. Difference in GI intake between comparison groups varied widely from 0.6 to 42.None of the included studies reported the effect of low GI dietary intake on cardiovascular mortality and cardiovascular events such as fatal and nonfatal myocardial infarction, unstable angina, coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, and stroke. The unclear risk of bias of most of the included studies makes overall interpretation of the data difficult. Only two of the included studies (38 participants) reported on adverse effects and did not observe any harms (low-quality evidence).
AUTHORS' CONCLUSIONS
There is currently no evidence available regarding the effect of low GI diets on cardiovascular disease events. Moreover, there is currently no convincing evidence that low GI diets have a clear beneficial effect on blood lipids or blood pressure parameters.
Topics: Adult; Aged; Blood Glucose; Blood Pressure; Cardiovascular Diseases; Dietary Carbohydrates; Fasting; Glycemic Index; Humans; Lipids; Middle Aged; Primary Prevention; Secondary Prevention; Weight Loss
PubMed: 28759107
DOI: 10.1002/14651858.CD004467.pub3 -
Neuroscience and Biobehavioral Reviews Sep 2017The brain-gut-axis is an interdependent system affecting neural functions and controlling our eating behaviour. In recent decades, neuroimaging techniques have... (Review)
Review
The brain-gut-axis is an interdependent system affecting neural functions and controlling our eating behaviour. In recent decades, neuroimaging techniques have facilitated its investigation. We systematically looked into functional and neurochemical brain imaging studies investigating how key molecules such as ghrelin, glucagon-like peptide-1 (GLP-1), peptide tyrosine-tyrosine (PYY), cholecystokinin (CCK), leptin, glucose and insulin influence the function of brain regions regulating appetite and satiety. Of the 349 studies published before July 2016 identified in the database search, 40 were included (27 on healthy and 13 on obese subjects). Our systematic review suggests that the plasma level of ghrelin, the gut hormone promoting appetite, is positively correlated with activation in the pre-frontal cortex (PFC), amygdala and insula and negatively correlated with activation in subcortical areas such as the hypothalamus. In contrast, the plasma levels of glucose, insulin, leptin, PYY, GLP-1 affect the same brain regions conversely. Our study integrates previous investigations of the gut-brain matrix during food-intake and homeostatic regulation and may be of use for future meta-analyses of brain-gut interactions.
Topics: Appetite; Brain; Gastrointestinal Tract; Hormones; Humans; Satiation
PubMed: 28669754
DOI: 10.1016/j.neubiorev.2017.06.013 -
Sleep Medicine Reviews Aug 2017Obesity and obstructive sleep apnea (OSA) have a reciprocal relationship. Sleep disruptions characteristic of OSA may promote behavioral, metabolic, and/or hormonal... (Review)
Review
UNLABELLED
Obesity and obstructive sleep apnea (OSA) have a reciprocal relationship. Sleep disruptions characteristic of OSA may promote behavioral, metabolic, and/or hormonal changes favoring weight gain and/or difficulty losing weight. The regulation of energy balance (EB), i.e., the relationship between energy intake (EI) and energy expenditure (EE), is complex and multi-factorial, involving food intake, hormonal regulation of hunger/satiety/appetite, and EE via metabolism and physical activity (PA). The current systematic review describes the literature on how OSA affects EB-related parameters. OSA is associated with a hormonal profile characterized by abnormally high leptin and ghrelin levels, which may encourage excess EI. Data on actual measures of food intake are lacking, and not sufficient to make conclusions. Resting metabolic rate appears elevated in OSA vs.
CONTROLS
Findings on PA are inconsistent, but may indicate a negative relationship with OSA severity that is modulated by daytime sleepiness and body weight. A speculative explanation for the positive EB in OSA is that the increased EE via metabolism induces an overcompensation in the drive for hunger/food intake, which is larger in magnitude than the rise in EI required to re-establish EB. Understanding how OSA affects EB-related parameters can help improve weight loss efforts in these patients.
Topics: Eating; Energy Metabolism; Exercise; Humans; Leptin; Obesity; Polysomnography; Sleep Apnea, Obstructive
PubMed: 27818084
DOI: 10.1016/j.smrv.2016.07.001 -
Endocrine-related Cancer Sep 2016Ghrelin is a hormone with multiple physiologic functions, including promotion of growth hormone release, stimulation of appetite and regulation of energy homeostasis.... (Review)
Review
Ghrelin is a hormone with multiple physiologic functions, including promotion of growth hormone release, stimulation of appetite and regulation of energy homeostasis. Treatment with ghrelin/ghrelin-receptor agonists is a prospective therapy for disease-related cachexia and malnutrition. In vitro studies have shown high expression of ghrelin in cancer tissue, although its role including its impact in cancer risk and progression has not been established. We performed a systematic literature review to identify peer-reviewed human or animal in vivo original research studies of ghrelin, ghrelin-receptor agonists, or ghrelin genetic variants and the risk, presence, or growth of cancer using structured searches in PubMed database as well as secondary searches of article reference lists, additional reviews and meta-analyses. Overall, 45 (73.8%) of the 61 studies reviewed, including all 11 involving exogenous ghrelin/ghrelin-receptor agonist treatment, reported either a null (no statistically significant difference) or inverse association of ghrelin/ghrelin-receptor agonists or ghrelin genetic variants with cancer risk, presence or growth; 10 (16.7%) studies reported positive associations; and 6 (10.0%) reported both negative or null and positive associations. Differences in serum ghrelin levels in cancer cases vs controls (typically lower) were reported for some but not all cancers. The majority of in vivo studies showed a null or inverse association of ghrelin with risk and progression of most cancers, suggesting that ghrelin/ghrelin-receptor agonist treatment may have a favorable safety profile to use for cancer cachexia. Additional large-scale prospective clinical trials as well as basic bioscientific research are warranted to further evaluate the safety and benefits of ghrelin treatment in patients with cancer.
Topics: Animals; Ghrelin; Humans; Neoplasms; Receptors, Ghrelin
PubMed: 27552970
DOI: 10.1530/ERC-16-0130 -
Sports Medicine (Auckland, N.Z.) Dec 2016It has been proposed that habitual physical activity improves appetite control; however, the evidence has never been systematically reviewed. (Review)
Review
BACKGROUND
It has been proposed that habitual physical activity improves appetite control; however, the evidence has never been systematically reviewed.
OBJECTIVE
To examine whether appetite control (e.g. subjective appetite, appetite-related peptides, food intake) differs according to levels of physical activity.
DATA SOURCES
Medline, Embase and SPORTDiscus were searched for articles published between 1996 and 2015, using keywords pertaining to physical activity, appetite, food intake and appetite-related peptides.
STUDY SELECTION
Articles were included if they involved healthy non-smoking adults (aged 18-64 years) participating in cross-sectional studies examining appetite control in active and inactive individuals; or before and after exercise training in previously inactive individuals.
STUDY APPRAISAL AND SYNTHESIS
Of 77 full-text articles assessed, 28 studies (14 cross-sectional; 14 exercise training) met the inclusion criteria.
RESULTS
Appetite sensations and absolute energy intake did not differ consistently across studies. Active individuals had a greater ability to compensate for high-energy preloads through reductions in energy intake, in comparison with inactive controls. When physical activity level was graded across cross-sectional studies (low, medium, high, very high), a significant curvilinear effect on energy intake (z-scores) was observed.
LIMITATIONS
Methodological issues existed concerning the small number of studies, lack of objective quantification of food intake, and various definitions used to define active and inactive individuals.
CONCLUSION
Habitually active individuals showed improved compensation for the energy density of foods, but no consistent differences in appetite or absolute energy intake, in comparison with inactive individuals. This review supports a J-shaped relationship between physical activity level and energy intake. Further studies are required to confirm these findings.
PROSPERO REGISTRATION NUMBER
CRD42015019696.
Topics: Appetite; Appetite Regulation; Energy Intake; Exercise; Humans; Satiation
PubMed: 27002623
DOI: 10.1007/s40279-016-0518-9 -
Chemical Senses Feb 2012Consumption of spicy foods containing capsaicin, the major pungent principle in hot peppers, reportedly promotes negative energy balance. However, many individuals... (Meta-Analysis)
Meta-Analysis Review
Consumption of spicy foods containing capsaicin, the major pungent principle in hot peppers, reportedly promotes negative energy balance. However, many individuals abstain from spicy foods due to the sensory burn and pain elicited by the capsaicin molecule. A potential alternative for nonusers of spicy foods who wish to exploit this energy balance property is consumption of nonpungent peppers rich in capsiate, a recently identified nonpungent capsaicin analog contained in CH-19 Sweet peppers. Capsiate activates transient receptor potential vanilloid subtype 1 (TRPV1) receptors in the gut but not in the oral cavity. This paper critically evaluates current knowledge on the thermogenic and appetitive effects of capsaicin and capsiate from foods and in supplemental form. Meta-analyses were performed on thermogenic outcomes, with a systematic review conducted for both thermogenic and appetitive outcomes. Evidence indicates that capsaicin and capsiate both augment energy expenditure and enhance fat oxidation, especially at high doses. Furthermore, the balance of the literature suggests that capsaicin and capsiate suppress orexigenic sensations. The magnitude of these effects is small. Purposeful inclusion of these compounds in the diet may aid weight management, albeit modestly.
Topics: Appetite; Appetite Regulation; Body Weight; Capsaicin; Energy Metabolism; Humans; Mouth; Randomized Controlled Trials as Topic; TRPV Cation Channels; Taste; Thermogenesis
PubMed: 22038945
DOI: 10.1093/chemse/bjr100 -
Journal of Genetics Apr 2011Cancer cachexia is a polygenic and complex syndrome. Genetic variations in regulation of the inflammatory response, muscle and fat metabolic pathways, and pathways in... (Review)
Review
Cancer cachexia is a polygenic and complex syndrome. Genetic variations in regulation of the inflammatory response, muscle and fat metabolic pathways, and pathways in appetite regulation are likely to contribute to the susceptibility or resistance to developing cancer cachexia. A systematic search of Medline and EmBase databases, covering 1986-2008 was performed for potential candidate genes/genetic polymorphisms relating to cancer cachexia. Related genes were then identified using pathway functional analysis software. All candidate genes were reviewed for functional polymorphisms or clinically significant polymorphisms associated with cachexia using the OMIM and GeneRIF databases. Genes with variants which had functional or clinical associations with cachexia and replicated in at least one study were entered into pathway analysis software to reveal possible network associations between genes. A total of 184 polymorphisms with functional or clinical relevance to cancer cachexia were identified in 92 candidate genes. Of these, 42 polymorphisms (in 33 genes) were replicated in more than one study with 13 polymorphisms found to influence two or more hallmarks of cachexia (i.e. inflammation, loss of fat mass and/or lean mass and reduced survival). Thirty-three genes were found to be significantly interconnected in two major networks with four genes (ADIPOQ, IL6, NFKB1 and TLR4) interlinking both networks. Selection of candidate genes and polymorphisms is a key element of multigene study design. The present study provides an initial framework to select genes/polymorphisms for further study in cancer cachexia, and to develop their potential as susceptibility biomarkers of developing cachexia.
Topics: Cachexia; Genetic Association Studies; Genetic Markers; Genetic Predisposition to Disease; Humans; Neoplasms; Polymorphism, Genetic
PubMed: 21677406
DOI: 10.1007/s12041-011-0027-4