Liling Xie1, Bo-Xin Zhao2, Jiajun Luo1, Youbao Li1, Fengxin Zhu1, Guo-Feng Li2, Mingli He3, Binyan Wang1, Hao Zhang4, Yefeng Cai5, Yong Huo6, Xiaobin Wang7, Fan Fan Hou1, Xiping Xu8, Xianhui Qin9, Jing Nie10. 1. State Key Laboratory of Organ Failure Research, National Clinical Research Center for Kidney Disease, Key Laboratory of Organ Failure Research (Ministry of Education), Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, PR China. 2. Department of Pharmacy, Rational Medication Evaluation and Drug Delivery Technology Lab, Guangdong Key Laboratory of New Drug Screening, Nanfang Hospital, Southern Medical University, Guangzhou, PR China. 3. Department of Neurology, First People's Hospital, Lianyungang, PR China. 4. Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, PR China. 5. Department of Neurology, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, PR China. 6. Department of Cardiology, Peking University First Hospital, Beijing, PR China. 7. Department of Population, Family and Reproductive Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, 21205, USA. 8. State Key Laboratory of Organ Failure Research, National Clinical Research Center for Kidney Disease, Key Laboratory of Organ Failure Research (Ministry of Education), Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, PR China; Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, PR China. 9. State Key Laboratory of Organ Failure Research, National Clinical Research Center for Kidney Disease, Key Laboratory of Organ Failure Research (Ministry of Education), Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, PR China. Electronic address: pharmaqin@126.com. 10. State Key Laboratory of Organ Failure Research, National Clinical Research Center for Kidney Disease, Key Laboratory of Organ Failure Research (Ministry of Education), Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, PR China. Electronic address: niejing@smu.edu.cn.
Abstract
BACKGROUND & AIMS: Betaine (a micronutrient) has important biological functions (e.g., preventing premature apoptosis and serving as a methyl donor). We investigated the association between baseline serum betaine and the incident risk of first stroke in hypertensive patients. METHODS: We conducted a nested case-control study, including 622 patients with first stroke (including 502 ischemic stroke, 118 hemorrhagic stroke and 2 uncertain type of stroke) and 622 matched controls from the China Stroke Primary Prevention Trial (CSPPT). The study was conducted from May 2008 to August 2013. The study outcomes included first stroke and its subtypes: first ischemic and hemorrhagic stroke. RESULTS: There was a U-shaped association between baseline serum betaine and the risk of first ischemic stroke. The risk of first ischemic stroke decreased with the increment of betaine (per 10 μmol/L increase: OR, 0.87; 95%CI: 0.77-0.99) in patients with betaine <77.7 μmol/L, while the risk of first ischemic stroke increased with the betaine increment (OR, 1.17; 95%CI: 1.01-1.36) in patients with betaine ≥77.7 μmol/L. However, there was no significant association between serum betaine and risk of first hemorrhagic stroke (per 10 μmol/L increase: OR, 0.98; 95%CI: 0.82-1.17). CONCLUSIONS: There was a U-shaped association between baseline betaine levels and the risk of first ischemic stroke in hypertensive patients, with a turning point at about 77.7 μmol/L. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00794885.
BACKGROUND & AIMS:Betaine (a micronutrient) has important biological functions (e.g., preventing premature apoptosis and serving as a methyl donor). We investigated the association between baseline serum betaine and the incident risk of first stroke in hypertensivepatients. METHODS: We conducted a nested case-control study, including 622 patients with first stroke (including 502 ischemic stroke, 118 hemorrhagic stroke and 2 uncertain type of stroke) and 622 matched controls from the China Stroke Primary Prevention Trial (CSPPT). The study was conducted from May 2008 to August 2013. The study outcomes included first stroke and its subtypes: first ischemic and hemorrhagic stroke. RESULTS: There was a U-shaped association between baseline serum betaine and the risk of first ischemic stroke. The risk of first ischemic stroke decreased with the increment of betaine (per 10 μmol/L increase: OR, 0.87; 95%CI: 0.77-0.99) in patients with betaine <77.7 μmol/L, while the risk of first ischemic stroke increased with the betaine increment (OR, 1.17; 95%CI: 1.01-1.36) in patients with betaine ≥77.7 μmol/L. However, there was no significant association between serum betaine and risk of first hemorrhagic stroke (per 10 μmol/L increase: OR, 0.98; 95%CI: 0.82-1.17). CONCLUSIONS: There was a U-shaped association between baseline betaine levels and the risk of first ischemic stroke in hypertensivepatients, with a turning point at about 77.7 μmol/L. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00794885.