Association Between Hypertension in Healthy Participants and Zinc and Copper Status: a Population-Based Study

The prevalence of hypertension (HTN) is increasing globally. It has been shown that there is an association between micronutrient deficiency and HTN. In the current study, we aimed to assess the association between HTN with serum copper and zinc concentrations in a large representative Iranian population. The participants were enrolled into the Mashhad stroke and heart atherosclerotic disorders study (MASHAD study), a cohort study that was initiated in 2010. Anthropometric indices were assessed using standard procedures. Systolic (SBP) and diastolic (DBP) blood pressures were measured using a standard mercury sphygmomanometer. Fasting blood glucose (FBG), lipid profile, uric acid and blood urea nitrogen (BUN), and hs-CRP were measured using routine methods. HTN defined as persons who had SBP ≥ 130 mmHg and/or DBP ≥ 85 mmHg and/or medication use. Flame atomic absorption (Varian AA240FS) was used to measure serum Zn and Cu concentrations. SPSS software was used for all statistical analyses. A total of 9588 participants were recruited into the MASHAD study project. Participants were divided into two groups; 5695 healthy (non-hypertensive) (mean age 45.85 ± 7.5 years) and 3893 hypertensive participants (mean age 51.18 ± 7.67 years). Systolic (p < 0.001) and diastolic blood pressure (p < 0.001) were significantly different for different serum copper quartiles. The participants with serum copper levels < 80 μg/dl had 1.33 times greater risk of an increased blood pressure than other participants. Participants with serum copper levels > 130 μg/dl had a 1.94-fold higher risk of raised blood pressure. Serum zinc was not associated with systolic blood pressure, but individuals in the first quartile level of serum zinc had a diastolic blood pressure that was significantly higher than other quartiles (p = 0.035). Serum copper is associated with blood pressure status in adults in a U-shaped relationship, with a range of serum copper between 80 and 130 μg/dl being associated with normal blood pressure.