Effect of green tea supplementation on blood pressure among overweight and obese adults: A protocol for a systematic review

BMJ Open

Volumn 4, Issue 4, 2014, Pages

  Li, Guowei ^a   Zhang, Yuan ^a   Mbuagbaw, Lawrence ^a   Holbrook, Anne ^a,b   Levine, Mitchell A H ^a,b   Thabane, Lehana ^a,b  

^a MCMASTER UNIVERSITY   (Canada)

^b ST JOSEPH S HOSPITAL   (Canada)

Author keywords

[No Author keywords available]

Indexed keywords

ANTIHYPERTENSIVE AGENT; GREEN TEA EXTRACT; PLACEBO; ANTIOXIDANT; PLANT EXTRACT; TEA; VASODILATOR AGENT;

ADULT DISEASE; BLOOD PRESSURE; DIET SUPPLEMENTATION; HUMAN; META ANALYSIS (TOPIC); OBESITY; QUALITY OF LIFE; RANDOMIZED CONTROLLED TRIAL (TOPIC); REVIEW; SYSTEMATIC REVIEW; TEA; THERAPY EFFECT; WEIGHT REDUCTION; ADVERSE EFFECTS; DIETARY SUPPLEMENT; DRUG EFFECTS; HYPERTENSION; PATHOPHYSIOLOGY;

ANTIOXIDANTS; BLOOD PRESSURE; DIETARY SUPPLEMENTS; HUMANS; HYPERTENSION; OBESITY; OVERWEIGHT; PLANT EXTRACTS; QUALITY OF LIFE; TEA; VASODILATOR AGENTS;

EID: 84899512790     PISSN: None     EISSN: 20446055     Source Type: Journal    
DOI: 10.1136/bmjopen-2014-004971     Document Type: Review

References (47)

1. World Health Organization. Obesity. [Updated March 2013, accessed January 2014]. http://www.who.int/topics/obesity/en/
2. Mikhail N, Golub MS, Tuck ML. Obesity and hypertension. Prog Cardiovasc Dis 1999;42:39-58. (Pubitemid 29439807)
3. Landsberg L, Aronne LJ, Beilin LJ, et al. Obesity-related hypertension: pathogenesis, cardiovascular risk, and treatment: a position paper of The Obesity Society and the American Society of Hypertension. J Clin Hypertens (Greenwich) 2013;15:14-33.
4. Kotsis V, Stabouli S, Papakatsika S, et al. Mechanisms of obesity-induced hypertension. Hypertens Res 2010;33:386-93.
5. Vuong QV. Epidemiological evidence linking tea consumption to human health: a review. Crit Rev Food Sci Nutr 2014;54:523-36.
6. Mukhtar H, Ahmad N. Tea polyphenols: prevention of cancer and optimizing health. Am J Clin Nutr 2000;71:1698S-702S.
7. Riemersma RA, Rice-Evans CA, Tyrrell RM, et al. Tea flavonoids and cardiovascular health. QJM 2001;94:277-82. (Pubitemid 32492751)
8. Ihm SH, Jang SW, Kim OR, et al. Decaffeinated green tea extract improves hypertension and insulin resistance in a rat model of metabolic syndrome. Atherosclerosis 2012;224:377-83.
9. Jang HJ, Ridgeway SD, Kim JA. Effects of the green tea polyphenol epigallocatechin-3-gallate on high-fat diet-induced insulin resistance and endothelial dysfunction. Am J Physiol Endocrinol Metab 2013;305:E1444-51.
10. Deka A, Vita JA. Tea and cardiovascular disease. Pharmacol Res 2011;64:136-45.
11. Johnson R, Bryant S, Huntley AL. Green tea and green tea catechin extracts: an overview of the clinical evidence. Maturitas 2012;73:280-7.
12. Zheng XX, Xu YL, Li SH, et al. Green tea intake lowers fasting serum total and LDL cholesterol in adults: a meta-analysis of 14 randomized controlled trials. Am J Clin Nutr 2011;94:601-10.
13. Kim A, Chiu A, Barone MK, et al. Green tea catechins decrease total and low-density lipoprotein cholesterol: a systematic review and meta-analysis. J Am Diet Assoc 2011;111:1720-9.
14. Potenza MA, Marasciulo FL, Tarquinio M, et al. EGCG, a green tea polyphenol, improves endothelial function and insulin sensitivity, reduces blood pressure, and protects against myocardial I/R injury in SHR. Am J Physiol Endocrinol Metab 2007;292:E1378-87. (Pubitemid 46684607)
15. Negishi H, Xu J-W, Ikeda K, et al. Black and green tea polyphenols attenuate blood pressure increases in stroke-prone spontaneously hypertensive rats. J Nutr 2004;134:38-42. (Pubitemid 38057420)
16. Peters U, Poole C, Arab L. Does tea affect cardiovascular disease? A meta-analysis. Am J Epidemiol 2001;154:495 -503.
17. Arab L, Liu W, Elashoff D. Green and black tea consumption and risk of stroke: a meta-analysis. Stroke 2009;40:1786-92.
18. Wang Z-M, Zhou B, Wang Y-S, et al. Black and green tea consumption and the risk of coronary artery disease: a meta-analysis. Am J Clin Nutr 2011;93:506-15.
19. Hooper L, Kroon PA, Rimm EB, et al. Flavonoids, flavonoid-rich foods, and cardiovascular risk: a meta-analysis of randomized controlled trials. Am J Clin Nutr 2008;88:38-50. (Pubitemid 351988681)
20. Taubert D, Roesen R, Schomig E. Effect of cocoa and tea intake on blood pressure: a meta-analysis. Arch Intern Med 2007;167:626.
21. Hartley L, Flowers N, Holmes J, et al. Green and black tea for the primary prevention of cardiovascular disease. Cochrane Database Syst Rev 2013;6:CD009934.
22. Shea BJ, Hamel C, Wells GA, et al. AMSTAR is a reliable and valid measurement tool to assess the methodological quality of systematic reviews. J Clin Epidemiol 2009;62:1013-20.
23. Bogdanski P, Suliburska J, Szulinska M, et al. Green tea extract reduces blood pressure, inflammatory biomarkers, and oxidative stress and improves parameters associated with insulin resistance in obese, hypertensive patients. Nutr Res 2012;32:421-7.
24. Brown AL, Lane J, Coverly J, et al. Effects of dietary supplementation with the green tea polyphenol epigallocatechin-3-gallate on insulin resistance and associated metabolic risk factors: randomized controlled trial. Br J Nutr 2009;101:886-94.
25. Nagao T, Hase T, Tokimitsu I. A green tea extract high in catechins reduces body fat and cardiovascular risks in humans. Obesity (Silver Spring) 2007;15:1473-83. (Pubitemid 47110911)
26. Brown AL, Lane J, Holyoak C, et al. Health effects of green tea catechins in overweight and obese men: a randomised controlled cross-over trial. Br J Nutr 2011;106:1880-9.
27. Suliburska J, Bogdanski P, Szulinska M, et al. Effects of green tea supplementation on elements, total antioxidants, lipids, and glucose values in the serum of obese patients. Biol Trace Elem Res 2012;149:315-22.
28. Basu A, Sanchez K, Leyva MJ, et al. Green tea supplementation affects body weight, lipids, and lipid peroxidation in obese subjects with metabolic syndrome. J Am Coll Nutr 2010;29:31-40.
29. Li G, Mbuagbaw L, Samaan Z, et al. Efficacy of vitamin D supplementation in depression in adults: a systematic review protocol. Syst Rev 2013;2:64.
30. Moher D, Liberati A, Tetzlaff J, et al. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. BMJ 2009;339:b2535.
31. Viera AJ, Garrett JM. Understanding interobserver agreement: the kappa statistic. Fam Med 2005;37:360-3. (Pubitemid 40656185)
32. Higgins JPT, Green S. Cochrane Handbook for Systematic Reviews of Interventions 5.1.0. [Updated March 2011]. http://handbook.cochrane.org
33. Furukawa TA, Barbui C, Cipriani A, et al. Imputing missing standard deviations in meta-analyses can provide accurate results. J Clin Epidemiol 2006;59:7-10. (Pubitemid 41797469)
34. Higgins JP, Thompson SG. Quantifying heterogeneity in a meta-analysis. Stat Med 2002;21:1539-58. (Pubitemid 34746062)
35. Higgins JP, Thompson SG, Deeks JJ, et al. Measuring inconsistency in meta-analyses. BMJ 2003;327:557-60. (Pubitemid 37088507)
36. Boehm K, Borrelli F, Ernst E, et al. Green tea (Camellia sinensis) for the prevention of cancer. Cochrane Database Syst Rev 2009;(3):CD005004.
37. Harbowy M, Ballentine D. Tea chemistry. Crit Rev Plant Sci 1997;16:415-80.
38. Wolfram S. Effects of green tea and EGCG on cardiovascular and metabolic health. J Am Coll Nutr 2007;26:373S-88S. (Pubitemid 47579907)
39. Hodgson JM, Croft KD. Tea flavonoids and cardiovascular health. Mol Aspects Med 2010;31:495-502.
40. Jurgens TM, Whelan AM, Killian L, et al. Green tea for weight loss and weight maintenance in overweight or obese adults. Cochrane Database Syst Rev 2012;12:CD008650.
41. MacMahon S, Cutler J, Brittain E, et al. Obesity and hypertension: epidemiological and clinical issues. Eur Heart J 1987;8(Suppl B):57-70. (Pubitemid 17091714)
42. Guyatt GH, Oxman AD, Vist GE, et al. GRADE: an emerging consensus on rating quality of evidence and strength of recommendations. BMJ 2008;336:924-6. (Pubitemid 351632017)
43. Flegal KM. Evaluating epidemiologic evidence of the effects of food and nutrient exposures. Am J Clin Nutr 1999;69:1339S-44S. (Pubitemid 29252080)
44. Nguyen DM, El-Serag HB. The epidemiology of obesity. Gastroenterol Clin North Am 2010;39:1.
45. Kotchen TA. Obesity-related hypertension: epidemiology, pathophysiology, and clinical management. Am J Hypertens 2010;23:1170-8.
46. Emberson J, Whincup P, Morris R, et al. Evaluating the impact of population and high-risk strategies for the primary prevention of cardiovascular disease. Eur Heart J 2004;25:484-91. (Pubitemid 38524273)
47. Sackett DL. Why randomized controlled trials fail but needn't: 2. Failure to employ physiological statistics, or the only formula a clinician-trialist is ever likely to need (or understand!). CMAJ 2001;165:1226-37. (Pubitemid 33042774)