Original Paper Ann Nutr Metab 2014;64:106–112 DOI: 10.1159/000363418
Received: April 5, 2014 Accepted after revision: May 5, 2014 Published online: June 25, 2014
The Metabolic Syndrome Is Associated with an Increased Risk of Colorectal Polyps Independent of Plasma Homocysteine Fang-Pei Chen a Hwei-Ming Wang b Feng-Fan Chiang b Chun-Che Lin c Shih-Chien Huang e Yi-Chia Huang a, d a
School of Nutrition, Chung Shan Medical University, b Division of Colorectal Surgery, Department of Surgery, Taichung Veterans General Hospital, c Division of Gastroenterology, and d Department of Nutrition, Chung Shan Medical University Hospital, and e Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan, ROC
Key Words Metabolic syndrome · Homocysteine · Colorectal polyps
Abstract Background/Aims: The links between the metabolic syndrome and homocysteine in relation to the risk of colorectal polyps are not understood. The purpose of this study was to investigate the association between the metabolic syndrome and homocysteine and further analyze the relationship between these two factors and the risk of colorectal polyps. Methods: This was a case-control study. A total of 135 participants with colorectal polyps (cases) and 110 participants without polyps (controls) were recruited. Results: There were 59 participants with the metabolic syndrome in the case group and 36 participants with the metabolic syndrome in the control group. The metabolic syndrome and its individual components, except for serum triglycerides, and homocysteine were associated with the risk of colorectal polyps. When the association of the metabolic syndrome and homocysteine with the risk of colorectal polyps was simultaneously considered, the association between homocysteine and the risk of colorectal polyps disappeared, but waist circumference, systolic and diastolic blood pressure, high-density lipoprotein cholesterol, and the metabolic syn-
© 2014 S. Karger AG, Basel 0250–6807/14/0642–0106$39.50/0 E-Mail [email protected] www.karger.com/anm
drome itself were still significant risk factors for the development of colorectal polyps. Conclusion: Although the metabolic syndrome and plasma homocysteine were individually related to the risk of colorectal polyps, the metabolic syndrome was a major contributing factor in relation to the risk of colorectal polyps independent of plasma homocysteine. © 2014 S. Karger AG, Basel
Introduction
Colorectal polyps are classified as hyperplastic or adenomatous based on the histologic type and are considered precursors of most colorectal cancers, especially adenomatous polyps [1–3]. A high-fat diet, low vegetable consumption and some lifestyle habits may contribute to the development of colorectal polyps [4–7]. The metabolic syndrome, a cluster of central obesity, hypertension, dyslipidemia, and impaired glucose tolerance, has more recently been associated with the recurrence of colorectal adenomas [8] and has been considered an independent risk factor for colorectal cancer [9–12] and polyps [13– 15]. Not only the metabolic syndrome itself but also its individual components, such as overweight status and dyslipidemia, were associated with the risk of colorectal Yi-Chia Huang School of Nutrition, Chung Shan Medical University No. 110, Sec 1, Jianguo N. Rd. Taichung 402, Taiwan (ROC) E-Mail ych @ csmu.edu.tw
polyps [16–18]. Although the exact pathogenetic involvement of the metabolic syndrome in the development of colorectal polyps is unknown, the metabolic syndrome may play a role in this development. Homocysteine is a well-known risk factor for cardiovascular diseases. In the last decade, much attention has also been paid to the relationship between high plasma homocysteine levels and the risk of colorectal polyps [19– 22]. Besides the many known risk factors (i.e. age, enzyme deficiencies and mutations, vitamin deficiencies, disease, and drugs) for developing hyperhomocysteinemia, the metabolic syndrome has been recently reported to be associated with increased plasma homocysteine concentrations [23–25]. In contrast with the results reported in some previous studies indicating that the metabolic syndrome or its components could increase homocysteine concentrations [23–25], a lack of a correlation between metabolic syndrome components and increased homocysteine concentrations was observed in other studies [26–28]. Since there is no consistent evidence to demonstrate the association between plasma homocysteine and the metabolic syndrome, further study is thus warranted. Although the metabolic syndrome and homocysteine have both individually been shown to be potential risk factors for the development of colorectal polyps, the links between the metabolic syndrome and the plasma homocysteine level in relation to the risk of colorectal polyps are not well understood. Thus, the purpose of this study was to investigate the association between the metabolic syndrome and homocysteine and further analyze the relationship between these two factors and the risk of colorectal polyps.
Methods Study Design and Subjects This study was a case-control design. The sample size of 124 subjects was based on detecting significantly correlated (r = 0.25) between homocysteine and the metabolic syndrome itself with 80% statistical power and a two-sided α level
Received: April 5, 2014 Accepted after revision: May 5, 2014 Published online: June 25, 2014
The Metabolic Syndrome Is Associated with an Increased Risk of Colorectal Polyps Independent of Plasma Homocysteine Fang-Pei Chen a Hwei-Ming Wang b Feng-Fan Chiang b Chun-Che Lin c Shih-Chien Huang e Yi-Chia Huang a, d a
School of Nutrition, Chung Shan Medical University, b Division of Colorectal Surgery, Department of Surgery, Taichung Veterans General Hospital, c Division of Gastroenterology, and d Department of Nutrition, Chung Shan Medical University Hospital, and e Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan, ROC
Key Words Metabolic syndrome · Homocysteine · Colorectal polyps
Abstract Background/Aims: The links between the metabolic syndrome and homocysteine in relation to the risk of colorectal polyps are not understood. The purpose of this study was to investigate the association between the metabolic syndrome and homocysteine and further analyze the relationship between these two factors and the risk of colorectal polyps. Methods: This was a case-control study. A total of 135 participants with colorectal polyps (cases) and 110 participants without polyps (controls) were recruited. Results: There were 59 participants with the metabolic syndrome in the case group and 36 participants with the metabolic syndrome in the control group. The metabolic syndrome and its individual components, except for serum triglycerides, and homocysteine were associated with the risk of colorectal polyps. When the association of the metabolic syndrome and homocysteine with the risk of colorectal polyps was simultaneously considered, the association between homocysteine and the risk of colorectal polyps disappeared, but waist circumference, systolic and diastolic blood pressure, high-density lipoprotein cholesterol, and the metabolic syn-
© 2014 S. Karger AG, Basel 0250–6807/14/0642–0106$39.50/0 E-Mail [email protected] www.karger.com/anm
drome itself were still significant risk factors for the development of colorectal polyps. Conclusion: Although the metabolic syndrome and plasma homocysteine were individually related to the risk of colorectal polyps, the metabolic syndrome was a major contributing factor in relation to the risk of colorectal polyps independent of plasma homocysteine. © 2014 S. Karger AG, Basel
Introduction
Colorectal polyps are classified as hyperplastic or adenomatous based on the histologic type and are considered precursors of most colorectal cancers, especially adenomatous polyps [1–3]. A high-fat diet, low vegetable consumption and some lifestyle habits may contribute to the development of colorectal polyps [4–7]. The metabolic syndrome, a cluster of central obesity, hypertension, dyslipidemia, and impaired glucose tolerance, has more recently been associated with the recurrence of colorectal adenomas [8] and has been considered an independent risk factor for colorectal cancer [9–12] and polyps [13– 15]. Not only the metabolic syndrome itself but also its individual components, such as overweight status and dyslipidemia, were associated with the risk of colorectal Yi-Chia Huang School of Nutrition, Chung Shan Medical University No. 110, Sec 1, Jianguo N. Rd. Taichung 402, Taiwan (ROC) E-Mail ych @ csmu.edu.tw
polyps [16–18]. Although the exact pathogenetic involvement of the metabolic syndrome in the development of colorectal polyps is unknown, the metabolic syndrome may play a role in this development. Homocysteine is a well-known risk factor for cardiovascular diseases. In the last decade, much attention has also been paid to the relationship between high plasma homocysteine levels and the risk of colorectal polyps [19– 22]. Besides the many known risk factors (i.e. age, enzyme deficiencies and mutations, vitamin deficiencies, disease, and drugs) for developing hyperhomocysteinemia, the metabolic syndrome has been recently reported to be associated with increased plasma homocysteine concentrations [23–25]. In contrast with the results reported in some previous studies indicating that the metabolic syndrome or its components could increase homocysteine concentrations [23–25], a lack of a correlation between metabolic syndrome components and increased homocysteine concentrations was observed in other studies [26–28]. Since there is no consistent evidence to demonstrate the association between plasma homocysteine and the metabolic syndrome, further study is thus warranted. Although the metabolic syndrome and homocysteine have both individually been shown to be potential risk factors for the development of colorectal polyps, the links between the metabolic syndrome and the plasma homocysteine level in relation to the risk of colorectal polyps are not well understood. Thus, the purpose of this study was to investigate the association between the metabolic syndrome and homocysteine and further analyze the relationship between these two factors and the risk of colorectal polyps.
Methods Study Design and Subjects This study was a case-control design. The sample size of 124 subjects was based on detecting significantly correlated (r = 0.25) between homocysteine and the metabolic syndrome itself with 80% statistical power and a two-sided α level
