International Journal of Cardiology 198 (2015) 91–92
Contents lists available at ScienceDirect
International Journal of Cardiology journal homepage: www.elsevier.com/locate/ijcard
Letter to the Editor
Vitamin D: A potential important therapeutic target for atrial fibrillation Mingxian Chen a, Lilei Yu b, Qiming Liu a, Hong Jiang b, Shenghua Zhou a,⁎ a b
Department of Cardiology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China Department of Cardiology, Renmin Hospital, Wuhan University, Wuhan, Hubei, China
a r t i c l e
i n f o
Article history: Received 28 June 2015 Accepted 30 June 2015 Available online 03 July 2015 Keywords: Vitamin D Cardiac disease Atrial fibrillation
Dear Editor, We have read a paper with great interest written by Thompson and colleagues concerning “Vitamin D deficiency and atrial fibrillation” [1]. In this review, they found that the relationship between vitamin D status and atrial fibrillation was ambiguous. Some studies revealed no association between 25[OH]-D levels and AF, whereas other researches directly provided the evidence that vitamin D deficiency potentially played a critical role in the pathogenesis of AF. This conflicting issue has been sustained. Accumulating research provided the evidence that vitamin D deficiency has been associated with cardiac diseases including hypertension, coronary artery disease and heart failure [2]. Due to the antioxidative and anti-inflammatory properties of vitamin D, vitamin D status also is speculated as a risk factor for AF. However, a study has been shown that vitamin D level has no relationship with AF, and indicates that vitamin D deficiency does not participate in the development of AF [3]. Meanwhile, Qayyum et al. also demonstrated that there was no association between vitamin D deficiency and the type of AF or complications to AF. Several reasons may contribute to the failure results [4]. First, the measure of vitamin D level was at a single point time, whether vitamin D could affect the initial development of AF remained unknown.
Second, there were insufficient participants of vitamin D deficiency involved in both studies. A more large-scale research needs further study to test the relationship. Third, two studies were limited to individuals of local population, but other racial or ethnic people may have the opposite effect. Additionally, only two researches have been unable to confirm the relationship between vitamin D status and AF. Subsequently, more and more recent studies demonstrated that a close association between vitamin D deficiency and AF. Demir et al. found a relationship between vitamin D deficiency and non-valvular AF [5]. Chen et al. observed that low vitamin D concentration was significantly related to non-valvular AF in Chinese patients and indicated that vitamin D deficiency was involved in the development of AF [6]. Importantly, Hanafy et al. revealed the direct electromechanical effects on the left atrium after vitamin D administration, enabling prevention or termination of atrial fibrillation, and found that vitamin D could effectively prevent and terminate AF [7]. The underlying mechanism of vitamin D in anti-AF needs further elucidation. Vitamin D negatively regulates renin-angiotensin system (RAAS) activity. Vitamin D modulates the inflammation and increases the release of anti-inflammatory factors. Vitamin D deficiency can enhance RAAS activity and activate inflammatory responses, which facilitate to the formation of AF substrate. Therefore, it suggests that vitamin D deficiency may be associated with the development of AF, and vitamin D would potentially be an important therapeutic target for treating atrial fibrillation. However, much more and large-scale researches need further study to confirm. Conflicts of interest The authors report no relationships that could be construed as a conflict of interest. Acknowledgment This work was supported by the grant from the National Natural Science Foundation of China No. 81270257. Reference
⁎ Corresponding author at: Department of Cardiology, The Second Xiangya Hospital of Central South University, No. 139 middle Renmin Road, Furong District, Changsha City, Hunan Province 410011, China. Tel.: +86 731 85294037; fax: +86 731 85533525. E-mail address: [email protected] (S. Zhou).
http://dx.doi.org/10.1016/j.ijcard.2015.06.177 0167-5273/© 2015 Elsevier Ireland Ltd. All rights reserved.
[1] J. Thompson, R. Nitiahpapand, P. Bhatti, A. Kourliouros, Vitamin D deficiency and atrial fibrillation, Int. J. Cardiol. 184 (2015) 159–162. [2] I. Mozos, O. Marginean, Links between vitamin D deficiency and cardiovascular diseases, Biomed. Res. Int. 2015 (2015) 109275. [3] M. Rienstra, S. Cheng, M.G. Larson, E.L. McCabe, S.L. Booth, P.F. Jacques, S.A. Lubitz, X. Yin, D. Levy, J.W. Magnani, P.T. Ellinor, E.J. Benjamin, T.J. Wang, Vitamin D status is not
92
Letter to the Editor
related to development of atrial fibrillation in the community, Am. Heart J. 162 (3) (2011) 538–541. [4] F. Qayyum, N.L. Landex, B.R. Agner, M. Rasmussen, C. Jøns, U. Dixen, Vitamin D deficiency is unrelated to type of atrial fibrillation and its complications, Dan. Med. J. 59 (9) (2012) A4505. [5] M. Demir, U. Uyan, M. Melek, The effects of vitamin D deficiency on atrial fibrillation, Clin. Appl. Thromb. Hemost. 20 (1) (2014) 98–103.
[6] W.R. Chen, Z.Y. Liu, Y. Shi, W. Yin da, H. Wang, Y. Sha, Y.D. Chen, Relation of low vitamin D to nonvalvular persistent atrial fibrillation in Chinese patients, Ann. Noninvasive Electrocardiol. 19 (2) (2014) 166–173. [7] D.A. Hanafy, S.L. Chang, Y.Y. Lu, Y.C. Chen, Y.H. Kao, J.H. Huang, S.A. Chen, Y.J. Chen, Electromechanical effects of 1,25-dihydroxyvitamin D with antiatrial fibrillation activities, J. Cardiovasc. Electrophysiol. 25 (3) (2014) 317–323.
Contents lists available at ScienceDirect
International Journal of Cardiology journal homepage: www.elsevier.com/locate/ijcard
Letter to the Editor
Vitamin D: A potential important therapeutic target for atrial fibrillation Mingxian Chen a, Lilei Yu b, Qiming Liu a, Hong Jiang b, Shenghua Zhou a,⁎ a b
Department of Cardiology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China Department of Cardiology, Renmin Hospital, Wuhan University, Wuhan, Hubei, China
a r t i c l e
i n f o
Article history: Received 28 June 2015 Accepted 30 June 2015 Available online 03 July 2015 Keywords: Vitamin D Cardiac disease Atrial fibrillation
Dear Editor, We have read a paper with great interest written by Thompson and colleagues concerning “Vitamin D deficiency and atrial fibrillation” [1]. In this review, they found that the relationship between vitamin D status and atrial fibrillation was ambiguous. Some studies revealed no association between 25[OH]-D levels and AF, whereas other researches directly provided the evidence that vitamin D deficiency potentially played a critical role in the pathogenesis of AF. This conflicting issue has been sustained. Accumulating research provided the evidence that vitamin D deficiency has been associated with cardiac diseases including hypertension, coronary artery disease and heart failure [2]. Due to the antioxidative and anti-inflammatory properties of vitamin D, vitamin D status also is speculated as a risk factor for AF. However, a study has been shown that vitamin D level has no relationship with AF, and indicates that vitamin D deficiency does not participate in the development of AF [3]. Meanwhile, Qayyum et al. also demonstrated that there was no association between vitamin D deficiency and the type of AF or complications to AF. Several reasons may contribute to the failure results [4]. First, the measure of vitamin D level was at a single point time, whether vitamin D could affect the initial development of AF remained unknown.
Second, there were insufficient participants of vitamin D deficiency involved in both studies. A more large-scale research needs further study to test the relationship. Third, two studies were limited to individuals of local population, but other racial or ethnic people may have the opposite effect. Additionally, only two researches have been unable to confirm the relationship between vitamin D status and AF. Subsequently, more and more recent studies demonstrated that a close association between vitamin D deficiency and AF. Demir et al. found a relationship between vitamin D deficiency and non-valvular AF [5]. Chen et al. observed that low vitamin D concentration was significantly related to non-valvular AF in Chinese patients and indicated that vitamin D deficiency was involved in the development of AF [6]. Importantly, Hanafy et al. revealed the direct electromechanical effects on the left atrium after vitamin D administration, enabling prevention or termination of atrial fibrillation, and found that vitamin D could effectively prevent and terminate AF [7]. The underlying mechanism of vitamin D in anti-AF needs further elucidation. Vitamin D negatively regulates renin-angiotensin system (RAAS) activity. Vitamin D modulates the inflammation and increases the release of anti-inflammatory factors. Vitamin D deficiency can enhance RAAS activity and activate inflammatory responses, which facilitate to the formation of AF substrate. Therefore, it suggests that vitamin D deficiency may be associated with the development of AF, and vitamin D would potentially be an important therapeutic target for treating atrial fibrillation. However, much more and large-scale researches need further study to confirm. Conflicts of interest The authors report no relationships that could be construed as a conflict of interest. Acknowledgment This work was supported by the grant from the National Natural Science Foundation of China No. 81270257. Reference
⁎ Corresponding author at: Department of Cardiology, The Second Xiangya Hospital of Central South University, No. 139 middle Renmin Road, Furong District, Changsha City, Hunan Province 410011, China. Tel.: +86 731 85294037; fax: +86 731 85533525. E-mail address: [email protected] (S. Zhou).
http://dx.doi.org/10.1016/j.ijcard.2015.06.177 0167-5273/© 2015 Elsevier Ireland Ltd. All rights reserved.
[1] J. Thompson, R. Nitiahpapand, P. Bhatti, A. Kourliouros, Vitamin D deficiency and atrial fibrillation, Int. J. Cardiol. 184 (2015) 159–162. [2] I. Mozos, O. Marginean, Links between vitamin D deficiency and cardiovascular diseases, Biomed. Res. Int. 2015 (2015) 109275. [3] M. Rienstra, S. Cheng, M.G. Larson, E.L. McCabe, S.L. Booth, P.F. Jacques, S.A. Lubitz, X. Yin, D. Levy, J.W. Magnani, P.T. Ellinor, E.J. Benjamin, T.J. Wang, Vitamin D status is not
92
Letter to the Editor
related to development of atrial fibrillation in the community, Am. Heart J. 162 (3) (2011) 538–541. [4] F. Qayyum, N.L. Landex, B.R. Agner, M. Rasmussen, C. Jøns, U. Dixen, Vitamin D deficiency is unrelated to type of atrial fibrillation and its complications, Dan. Med. J. 59 (9) (2012) A4505. [5] M. Demir, U. Uyan, M. Melek, The effects of vitamin D deficiency on atrial fibrillation, Clin. Appl. Thromb. Hemost. 20 (1) (2014) 98–103.
[6] W.R. Chen, Z.Y. Liu, Y. Shi, W. Yin da, H. Wang, Y. Sha, Y.D. Chen, Relation of low vitamin D to nonvalvular persistent atrial fibrillation in Chinese patients, Ann. Noninvasive Electrocardiol. 19 (2) (2014) 166–173. [7] D.A. Hanafy, S.L. Chang, Y.Y. Lu, Y.C. Chen, Y.H. Kao, J.H. Huang, S.A. Chen, Y.J. Chen, Electromechanical effects of 1,25-dihydroxyvitamin D with antiatrial fibrillation activities, J. Cardiovasc. Electrophysiol. 25 (3) (2014) 317–323.
