A vegetarian diet may prevent elevation of blood pressures and lower the risk for hypertension through lower degrees of obesity, inflammation, and insulin resistance. This study investigated the association between a vegetarian diet and hypertension incidence in a cohort of Taiwanese adult nonsmokers and examined whether this association was mediated through inflammation, abdominal obesity, or insulin resistance (using fasting glucose as a proxy).
This matched cohort study was from the 1994–2008 MJ Health Screening Database. Each vegetarian was matched with five nonvegetarians by age, sex, and study site. The analysis included 4109 nonsmokers (3423 nonvegetarians and 686 vegetarians), followed for a median of 1.61 years. The outcome includes hypertension incidence, as well as SBP and DBP levels. Regression analysis was performed to assess the association between vegetarian diet and hypertension incidence or future blood pressure levels in the presence/absence of potential mediators.
Vegetarians had a 34% lower risk for hypertension, adjusting for age and sex (odds ratio: 0.66, 95% confidence interval: 0.50–0.87; SBP: −3.3 mmHg, P < 0.001; DBP: −1.5 mmHg, P < 0.001). The results stay statistically significant after further adjustment for C-reactive protein, waist circumference, and fasting glucose (odds ratio: 0.72, 95% confidence interval: 0.55–0.86; SBP: −2.4 mmHg, P < 0.05; DBP: −1.1 mmHg, P < 0.05). The protective association between vegetarian diet and hypertension appeared to be consistent across age groups.
Taiwanese vegetarians had lower incidence of hypertension than nonvegetarians. Vegetarian diets may protect against hypertension beyond lower abdominal obesity, inflammation, and insulin resistance.
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aInstitute of Population Health Sciences, National Health Research Institutes, Zhunan, Miaoli
bTzu Chi Medical Foundation, Hualien City, Hualien
cGraduate Institute of Epidemiology and Preventive Medicine, National Taiwan University
dMJ Health Research Foundation, Taipei, Taiwan, ROC
*Shao-Yuan Chuang and Tina H.T. Chiu contributed equally to this work.
Correspondence to Yen-Feng Chiu, Institute of Population Health Sciences, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli 35053, Taiwan, ROC. Tel: +886 37 246 166x36107; fax: +886 37 586 467; e-mail: firstname.lastname@example.org
Abbreviations: BP, blood pressure; CHD, coronary heart disease; CI, confidence interval; CRP, C-reactive protein; DASH, dietary approach to stop hypertension; FBG, fasting blood glucose; FFQ, food frequency questionnaire; HDL-C, high-density lipoprotein cholesterol; HOMA-IR, homeostasis model assessment of insulin resistance; HT, hypertension; LDL-C, low-density lipoprotein cholesterol; LTPA, leisure-time physical activity; MS, metabolic syndrome (ATP III); OR, odds ratio; RCT, randomized controlled trial; RR, relative risk (approximated by odds ratio here); TG, triglycerides; TLC, therapeutic lifestyle changes; WC, waist circumference
Received 12 November, 2015
Revised 4 June, 2016
Accepted 8 July, 2016
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