Magnesium deficiency or hypomagnesemia is an electrolyte imbalance characterized by serum magnesium levels below 1.5-2.5 mEq/L. Magnesium is essentially important in the maintenance of the cardiovascular and the nervous system. Magnesium is normally excreted through the kidneys and any abnormalities in the kidneys that lead to the increased excretion of magnesium will consequently result in magnesium deficiency.
The following symptoms and signs are closely associated with magnesium deficiency among patients:
The following diagnostic modalities and tests are available for the workup of patients suspected with magnesium deficiency:
In patients presenting with hypomagnesemia and hypocalcemic signs with concurrent arrhythmia, an intravenous drip of magnesium sulfate of up to 50 milliequivalents in a period of 8 to 24 hours, repeated in 3 to 5 days, can correct the symptoms of the deficiency. Oral doses of magnesium chloride and magnesium lactate may be given as maintenance doses to correct magnesium deficiency among patients.
Calcium supplementations and potassium supplementations can also be given to patients suffering from magnesium deficiency with concurrent hypocalcemia and hypomagnesemia to allay the untoward effects brought about by the electrolyte imbalance . Patients suffering from renal insufficiency with high renal creatinine clearance can only be given intravenous magnesium sulfate in up to 25% to 50% of the normal dose to prevent inadvertent hypermagnesemia . Patients with mild magnesium deficiency can benefit from eating green leafy vegetables, rice grains, and legumes which are naturally rich in elemental magnesium .
Magnesium deficiency has a good prognosis in general, especially when diagnosed and treated promptly. Morbidity and mortality incidences associated with hypomagnesemia correlate closely with it comorbid events like heart failure, pregnancy induced hypertension (PIH), and diabetes. The mild untoward signs and symptoms seen in magnesium deficiency are easily correctable by the supplementary replacement of the element in the diet.
In the United States, people suffering from magnesium deficiency number to about 2% of the population. Studies have inferred that more than three fourths of Americans could not meet the recommended daily allowance of dietary magnesium . More than 60% of alcoholics are likely to suffer from magnesium deficiency. A fourth of the patients who are diagnosed with diabetes have a concurrent hypomagnesemia. Cohort studies have demonstrated that neonates have a higher demand for intracellular magnesium, and are more likely to suffer from magnesium deficiency than their older counterparts.
Magnesium deficiency is already recognized as a significant etiologic factor in the propagation of cardiac arrhythmias . Imbalances in magnesium concentration directly affect cardiac electrical activities, myocardial contractility, and general vascular tone. A significant drop in magnesium levels has been demonstrated to prolong conduction with a slight ST wave depression. Even patients presenting with mild hypomagnesemia can result in dire consequences especially among cardiac patients with established congestive heart failure and myocardial ischemia . A progressive decrease in intracellular magnesium can increase vascular tone and resistance causing hypertension in most patients.
Magnesium has been found to stabilize the threshold potential of axons in neuromuscular systems. Any significant decrease in magnesium brings the neural cells into a hyperexcitable state causing tetany, hyperreflexia, muscle crampings, and seizures. The decreasing intracellular magnesium concentration diminishes the estrogen release thereby, worsens the osteoporotic process among post-menopausal women . One of the main function of magnesium is to increase the cell’s sensitivity to insulin, thus, hypomagnesemia is usually a comorbid event among diabetics.
High risk patients should have a healthy balance of diet rich in magnesium like sunflower seeds, almonds, cashew, soy products, avocados, and brown rice to prevent magnesium deficiency. High risk patients, especially diabetic, should control alcohol intake to prevent progressive loss of magnesium. Patients on magnesium wasting diuretics suffering from hypomagnesemia should have their maintenance medications revised to prevent further magnesium loss in the urine.
Magnesium deficiency is also defined as serum magnesium falling below 0.70 mmol/L caused by inadequate magnesium intake or impaired renal excretion of the element. Magnesium deficiency states often coexists with hypokalemia and hypocalcemia presenting as lethargy, arrhythmias, seizures, tetany, and tremors. Magnesium deficiency is easily corrected with magnesium replacement.
Definition: Magnesium deficiency or hypomagnesemia is an electrolyte imbalance characterized by magnesium levels below 1.5-2.5 mEq/L causing significant effects in the neuromuscular system and the cardiovascular system of affected patients.
Cause: Magnesium deficiency can be caused by low dietary intake of magnesium and kidney problems that lead to excessive magnesium wastage. Patients with irritable bowel diseases, patients with nephrotoxic drugs, and pregnant women can also be prone to magnesium deficiency.
Diagnosis: The diagnostic workup for patients with magnesium deficiency includes magnesium serum and excretory levels, blood tests for phosphate, calcium, and potassium levels, and ECG.
Treatment and follow-up: Intravenous replacement with magnesium sulfate for symptomatic patients with hypocalcemia, oral magnesium chloride and magnesium lactate for milder cases, and dietary supplementations of exogenous magnesium are the main treatment options.