Objective: To determine the prevalence of electrolyte
disturbances in patients with chronic, stable asthma, and to assess
whether the therapeutic agents used to treat chronic asthma have an
effect on abnormal electrolyte levels.
Prospective, hospital-based, cross-sectional study.
Setting: University teaching hospital in Jeddah, Saudi
Patients: Patients with chronic, stable
Method: Ninety-three consecutive patients with
chronic, stable asthma were involved in the study. On the day of the
visit to the asthma clinic, particulars such as age, sex, duration of
asthma, and details of drug therapy were obtained from each asthmatic
patient. Serum potassium, magnesium, phosphorus, calcium, and sodium
levels were measured. Normal values were as follows: potassium, 3.5 to
5 mmol/L; magnesium, 0.74 to 1.2 mmol/L; phosphorus, 0.8 to 1.4 mmol/L;
and calcium, 2.1 to 2.6 mmol/L.
disturbances were found in 43% of the patients; 85% of the patients
had one electrolyte disturbance, 10% had two electrolyte disturbances,
and 5% had three electrolyte disturbances. The highest proportions
were for magnesium (26.9%) and phosphorus (15.1%) [serum levels were
0.69 ± 0.04 mmol/L and 0.64 ± 0.09 mmol/L, respectively], the
lowest proportions were for potassium (5.4%) and sodium (4.3%)[
serum levels were 3.3 ± 0.01 mmol/L and 133 ± 0.01 mmol/L,
respectively], and no patient had a calcium disturbance. Logistic
regression analysis showed no statistically significant association
between the therapy used and electrolyte disturbances.
Conclusion: Hypomagnesemia and hypophosphatemia were found
to be the two most common electrolyte disturbances in patients with
chronic, stable asthma. Therapeutic agents used to treat patients with
chronic asthma have no effect on abnormal electrolyte levels. The
underlying cause still remains unclear.