Magnesium deficiency in hospitalized patients with hypokalemia

Background: When magnesium deficiency coexists with hypokalemia, it aggravates the hypokalemia, potentiates its adverse effects, and also renders it refractory to treatment. Despite the impact of magnesium deficiency on the clinical effects of hypokalemia, plasma magnesium is not routinely measured in patients with hypokalemia in our setting. Objectives: The objective of this study was to examine the frequency of hypomagnesemia among hospitalized patients with hypokalemia at a tertiary hospital in Northeastern Nigeria. Subjects and Methods: A cross-sectional analytical study carried out among 80 hospitalized patients (40 with hypokalemia and 40 with normal plasma potassium). Clinical details of the study individuals were obtained from hospital case notes. Plasma magnesium was measured, and the frequency of hypomagnesemia was compared between the two study groups. Results: The mean plasma magnesium was significantly lower in the hypokalemic group than in the normokalemic group (0.67 ± 0.05 vs. 0.81 ± 0.04 mmol/L, P < 0.05). The frequency of hypomagnesemia in the hypokalemic participants was higher than in normokalemic participants (52.5% vs. 22.5%). Hypomagnesemia was twice as likely to be found in the hypokalemic participants as in the normokalemic participants. Conclusions: Hypomagnesemia is common among hospitalized patients with hypokalemia in our setting. We recommend further studies, using larger sample size, which will identify clinical conditions that are frequently associated with the simultaneous occurrence of these two disturbances and determine the clinical value of routine measurement of magnesium in patients with hypokalemia in our setting.