Low Serum Magnesium Levels and Its Association with High Blood Pressure in Children

ObjectiveTo evaluate the association of hypomagnesemia with prehypertension (preHTN) and hypertension in children.Study designA total of 3954 apparently healthy Mexican children were enrolled in a cross-sectional study. Exclusion criteria were type 2 diabetes; hepatic, renal, or endocrine disease; impaired fasting glucose; chronic diarrhea; and intake of vitamins or magnesium supplements in the previous 6 months. preHTN was defined by systolic and/or diastolic blood pressure ≥90th to <95th percentile and hypertension by systolic and/or diastolic blood pressure ≥95th percentile, according to age, sex, and height percentile. Hypomagnesemia was defined by serum magnesium concentration <1.8 mg/dL (<0.74 mmol/L). To control for potential sources of bias related to age, participants were allocated into 2 groups, aged 6-10 years and 11-15 years.ResultsThe prevalence of preHTN and hypertension was 12.2% and 6.4%, respectively, in children aged 6-10 years and 13.9% and 10.6% in those aged 11-15 years. Hypomagnesemia was identified in 59 children with preHTN (27.3%) and 52 (45.6%) with hypertension in the 6-10 year age group, and in 115 children with preHTN (36.0%) and 109 (49.6%) with hypertension in the 11-15 year age group. Adjusted multiple logistic regression analysis showed that in children in both age groups, hypomagnesemia was associated with both preHTN (6-10 years: OR, 2.18, P < .0005; 11-15 years: OR, 1.38, P = .018) and hypertension (6-10 years: OR, 4.87, P < .0005; 11-15 years: OR, 1.83, P = .0002).ConclusionOur results indicate that serum magnesium level <1.8 mg/dL is significantly associated with preHTN and hypertension in apparently healthy children.