Serum Magnesium is associated with Carotid Atherosclerosis in patients with high cardiovascular risk (CORDIOPREV Study)

Abstract

This study aimed to ascertain whether there is an independent association between serum magnesium (Mg) and the Carotid Intima-Media Thickness (IMT-CC), a well-accepted atherosclerotic-biomarker surrogate of cardiovascular disease (CVD), in a population with high cardiovascular risk. Serum Mg and traditional atherosclerotic risk factors were recorded in 939 patients (mean age, 59.6 ± 0.3 years, 83.2% men) with coronary heart disease (CHD) enrolled in the CORDIOPREV trial. Serum Mg strongly associated with IMT-CC. Before adjusting for potential confounding factors, IMT-CC decreased by 0.111 ± 0.011 mm per mg/dl increase in serum Mg ( p < 0.001). After adjustment, the effect of Mg did not appear mediated through factors related to glucose metabolism, the lipid profile or the mineral metabolism and renal function. Multivariate models showed the lower Mg levels (quartile 1) as a strong independent factor contributing to IMT-CC along with age, sex, SBP, HDL-C, and diuretic use. Logistic regression analysis confirmed the predictive ability of serum Mg to differentiate patients at higher atherosclerotic risk as defined by an IMT-CC ≥ 1.0 mm, yielding a OR for the lower quartile of 10.623 (95%CI 2.311–48.845; P = 0.002) and a ROC-derived cutoff of 1.61 mg/dl. Therefore, our findings outline low serum magnesium as a possible independent risk factor for carotid atherosclerosis.

Influence of Demographic and Lifestyle Variables on Plasma Magnesium Concentrations and Their Associations with Cardiovascular Risk Factors in a Mediterranean Population

“…Some studies showed a statistically significant inverse association between plasma magnesium and total or LDL-cholesterol [95,96], but other studies did not observe any significant association [38,55,57,97]. Moreover, there are numerous publications [53,56,57,98,99], that, in agreement with our results, found statistically significant direct associations between plasma magnesium concentrations and total and/or LDL-cholesterol levels, but they did not emphasize the findings. If confirmed in later studies, these findings may help to explain inconsistent results in some studies analyzing plasma magnesium and cardiovascular risk due to the concomitant increase in the atherogenic LDL-cholesterol, but more research must be done on the potential mechanisms involved.…”

“…Also, in southern Spain, but analyzing subjects at high cardiovascular risk, Rodriguez-Ortiz at al. [53] detected statistically significant age differences, but no differences depending on sex, BMI or tobacco smoking. Conversely, Bertinato et al [86], analyzing a representative population from Canada, described statistically significant differences in serum concentrations depending on the sex, age and BMI.…”

“…The relative lack of symptoms of hypomagnesemia until plasma concentrations reach severely low levels as well as the relatively poor understanding of magnesium metabolism may have contributed to this relatively low awareness for hypomagnesemia. Recently, another study carried out in the south of Spain in patients with coronary heart disease recruited in the CORDIOPREV trial [53] also reported a strong cross-sectional association between serum magnesium concentration and the prevalence of type-2 diabetes. Moreover, in this study, serum magnesium was strongly and inversely associated with the Carotid Intima-Media Thickness, even after adjustment for diabetes.…”

“…Focusing on factors related to serum magnesium concentrations, no statistically significant differences were detected per sex, age, BMI, or smoking status in our population. These factors have been analyzed in various studies [15,53,55,63,77,86], obtaining different results depending on the population analyzed. Mataix et al [15], in a study undertaken to identify factors influencing plasma magnesium levels in the general population of southern Spain, and in agreement with our results, did not observe any association between plasma levels of magnesium and sex, age, obesity, tobacco smoking, alcohol drinking, educational level or sedentarism.…”

“…Several prospective cohort studies have analyzed plasma magnesium concentrations and cardiovascular disease incidence and diabetes risk, and some of them reported inverse associations in a meta-analysis [51]. Although at the cross-sectional level numerous researchers have investigated associations between plasma magnesium concentrations and cardiovascular risk factors including plasma lipids, blood pressure, fasting glucose/diabetes, inflammation markers, among others, the consistency (except for type-2 diabetes), is still low [14,[52][53][54][55][56][57][58]. Therefore, further studies are required on different populations in order to better understand those associations as well as the demographic and lifestyle factors associated with plasma magnesium concentrations.…”