Associations of Serum and Red Blood Cell Folate With All-Cause and Cardiovascular Mortality Among Hypertensive Patients With Elevated Homocysteine

Long Zhou; Hui Huang; Xiaoxiao Wen; Yu Chen; Jie Liao; Fuli Chen; Liancheng Zhao; Mingjiang Liu; Jianhong Tao; Gang Li

doi:10.3389/fnut.2022.849561

Associations of Serum and Red Blood Cell Folate With All-Cause and Cardiovascular Mortality Among Hypertensive Patients With Elevated Homocysteine

Front Nutr. 2022 Feb 25:9:849561. doi: 10.3389/fnut.2022.849561. eCollection 2022.

Authors

Long Zhou¹, Hui Huang¹, Xiaoxiao Wen², Yu Chen¹, Jie Liao¹, Fuli Chen¹, Liancheng Zhao³, Mingjiang Liu¹, Jianhong Tao¹, Gang Li¹

Affiliations

¹ Department of Cardiology, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China.
² Department of Epidemiology, College of Public Health and Health Professions and College of Medicine, University of Florida, Gainesville, FL, United States.
³ Division of Prevention and Community Health, National Center for Cardiovascular Disease, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.

Abstract

Objectives: This study aims to explore the associations between serum and red blood cell (RBC) folate as indicators of short- and long-term folate status, respectively, and all-cause as well as CVD mortality among hypertensive patients with elevated homocysteine.

Methods: A prospective cohort study of the National Health and Nutrition Examination Survey (1999-2006) and 2015 Linked Mortality File was performed. All-cause and CVD mortality risk estimated using Cox proportional hazards models with adjusting for multiple potential covariates.

Results: A total of 1,753 hypertensive patients with elevated homocysteine [mean (SD) age, 68.5 (13.1)] were included in the analysis. During a median follow-up of 10.0 years, a total of 899 all-cause and 257 CVD deaths occurred. Compared the highest with the lowest quartile of RBC folate, the multivariable adjusted hazard ratios and 95% confidence intervals for all-cause and CVD death were 1.13 (0.92-1.39) and 1.47 (1.01-2.16) respectively. There was a significant and positive trend between RBC folate and the risk of CVD death (p for trend = 0.0196). No significant association was found between serum folate and mortality risk among the study sample.

Conclusions: High level of RBC folate is associated with an increased risk of cardiovascular mortality among hypertensive patients with elevated homocysteine while serum folate has no such effects.

Keywords: homocysteine; hypertension; mortality; red blood cell; serum folate.