Efeitos da suplementação de magnésio sobre os fatores de risco cardiovasculares em pacientes hipertensos não controlados

Abstract

Studies have shown the importance of magnesium (Mg) in cardiovascular risk factors (CVR), acting both in the prevention and treatment of cardiovascular diseases, especially in arterial hypertension. The aim of the study was to evaluate the effects of Mg supplementation on CVR factors in uncontrolled hypertensive patients. Prospective study double blind with hypertensive patients, of both sexes, aged between 40 and 65 years old, initially submitted to clinical and nutritional evaluation, oscillometric measurement of blood pressure (BP), ambulatory blood pressure monitoring (ABPM), biochemical evaluation and 24-hour urine , determination of pulse wave velocity (PWV, Complior Analysis), central hemodynamic parameters (SphygmoCor), retinography and microvascular reactivity (Laser Speckle Contrast Image-Pericam). They were randomized to receive supplementation of 500 mg of chelated Mg or placebo for eight weeks. At the end of this period, the exams were repeated. Statistical analyzes were performed using the Statistical Package for the Social Sciences (SPSS) ® version 18.0. The results were presented in percentages or mean ± standard deviation. Fifty patients were analyzed, 26 patients in the placebo group and 24 patients in the Mg group. The Mg group showed a significant improvement in PWV (Mg 9.6 ± 1.7 vs 8.6 ± 2.2 m / s; placebo 9.7 ± 1.6 vs 9.8 ± 1.9 m / s, p = 0.049); in the delta of variation between the total cholesterol groups (Mg -23.9 ± 58.4; placebo 1.5 ± 24.1, p = 0.046); in the neutrophil / lymphocyte ratio (Mg -0.77 ± 0.86; placebo 0.49 ± 0.90, p = 0.027); in waist circumference in women (Mg -1.5 ± 2.3; placebo 0.2 ± 1.9, p = 0.039) and in waist-hip ratio (Mg -0.01 ± 0.02; placebo 0.01 ± 0.02, p = 0.009), especially in women. The Mg group showed a greater excretion of Mg in urine 24h both between the groups in the final values and in the variation delta (Mg 36.6 ± 60.0; placebo -1.9 ± 48.8, p = 0.024). Urinary Mg levels correlated with the glomerular filtration rate (r = 0.48; p = 0.026) and with serum creatinine (r = - 0.61; p = 0.003). In addition, correlate with the PWV (r = - 0.54; p = 0.006) and with the mean BP 24h (r = - 0.55; p = 0.005). Serum Mg levels correlated with endothelial function parameter assessed by varying the area on the curve (AUC) (r = 0.47; p = 0.018) and with the neutrophil / lymphocyte ratio (r = - 0.56; p = 0.004). The entire correlation was only in the Mg group. In the linear regression analysis, urinary Mg showed an independent and significant association with PWV (β = -15.93; p = 0.002) and with mean BP 24h (β = -1.43; p = 0.005) after adjusting for age and body mass index. In conclusion, the results of the present study suggest that in uncontrolled hypertensive patients, supplementation of 500 mg / day of chelated Mg improves parameters of arterial stiffness, inflammation, abdominal obesity and total cholesterol, important factors for CVR.