Lihua Hu1,2, Chonglei Bi3, Tengfei Lin4, Lishun Liu4, Yun Song4,5, Ping Wang6, Binyan Wang5,7, Chongqian Fang3, Hai Ma8, Xiao Huang2, Xiping Xu4, Hao Zhang4, Huiyuan Guo4, Xiaobin Wang9, Huihui Bao2, Jianping Li1, Xiaoshu Cheng2. 1. Department of Cardiology, Peking University First Hospital, Beijing, People's Republic of China. 2. Department of Cardiovascular Medicine, the Second Affiliated Hospital of Nanchang University, Nanchang of Jiangxi, People's Republic of China. 3. People's Hospital of Rongcheng, Shandong, People's Republic of China. 4. Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, People's Republic of China. 5. Shenzhen Evergreen Medical Institute, Shenzhen, People's Republic of China. 6. School of Public Health (Shenzhen), Sun Yat-Sen University, Guangzhou, People's Republic of China. 7. Institute of Biomedicine, Anhui Medical University, Hefei, People's Republic of China. 8. Health and Family planning Commission, Rongcheng, People's Republic of China. 9. Department of Population, Family and Reproductive Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA.
Abstract
BACKGROUND AND AIMS: Uncertainty remains regarding the association between the risk of stroke and plasma copper levels in population with copper mostly in normal range due to limited data. We examined the association between baseline plasma copper and risk of first stroke in Chinese community-dwelling population. METHODS: We conducted a nested case control study from 'H-type Hypertension and Stroke Prevention and Control Project'. A total of 1255 first stroke cases and 1255 controls matched for age, sex and study site were included in the analysis. Conditional logistic regression analyses were performed to evaluate the association between plasma copper and first stroke. RESULTS: The overall mean of copper was 15.90 (2.66) μmol/L. In total, 94.26% participants' copper concentration was in the normal range by Mayo Clinic laboratory reference values. Smoothing curve showed that the associations of plasma copper with first stroke and its subtypes were linear. Each standard deviation (SD) increment of plasma copper was independently and positively associated with risk of first stroke [odds ratio (OR): 1.17, 95% confidence interval (CI): 1.07-1.28]. The multivariable ORs with 95% CIs for total stroke, ischemic stroke and hemorrhagic stroke in the highest versus the lowest quartile of plasma copper were 1.49 (1.16-1.90; P-trend = 0.001), 1.46 (1.12-1.92; P-trend = 0.004) and 2.05 (0.95-4.38; P-trend = 0.050), respectively. CONCLUSIONS: Baseline plasma copper was positively associated with risk of first ischemic stroke in an approximately linear fashion among Chinese community population (80.32% hypertensives), although their copper levels were mostly within the normal range according to current reference values. Our findings warrant additional investigation.
BACKGROUND AND AIMS: Uncertainty remains regarding the association between the risk of stroke and plasma copper levels in population with copper mostly in normal range due to limited data. We examined the association between baseline plasma copper and risk of first stroke in Chinese community-dwelling population. METHODS: We conducted a nested case control study from 'H-type Hypertension and Stroke Prevention and Control Project'. A total of 1255 first stroke cases and 1255 controls matched for age, sex and study site were included in the analysis. Conditional logistic regression analyses were performed to evaluate the association between plasma copper and first stroke. RESULTS: The overall mean of copper was 15.90 (2.66) μmol/L. In total, 94.26% participants' copper concentration was in the normal range by Mayo Clinic laboratory reference values. Smoothing curve showed that the associations of plasma copper with first stroke and its subtypes were linear. Each standard deviation (SD) increment of plasma copper was independently and positively associated with risk of first stroke [odds ratio (OR): 1.17, 95% confidence interval (CI): 1.07-1.28]. The multivariable ORs with 95% CIs for total stroke, ischemic stroke and hemorrhagic stroke in the highest versus the lowest quartile of plasma copper were 1.49 (1.16-1.90; P-trend = 0.001), 1.46 (1.12-1.92; P-trend = 0.004) and 2.05 (0.95-4.38; P-trend = 0.050), respectively. CONCLUSIONS: Baseline plasma copper was positively associated with risk of first ischemic stroke in an approximately linear fashion among Chinese community population (80.32% hypertensives), although their copper levels were mostly within the normal range according to current reference values. Our findings warrant additional investigation.
Entities:
Keywords:
Plasma copper; first stroke; hemorrhagic stroke; hypertension; ischemic stroke