Chlorpropamide-induced hyponatremia in the veteran population.
OBJECTIVE
To determine the incidence and possible risk factors associated with chlorpropamide (CPA)-induced hyponatremia in the veteran population.


METHODS
Retrospective cohort study.


METHODS
Federal tertiary care medical center.


METHODS
Veterans receiving CPA from our facility with at least one serum sodium concentration below 135 mmol/L within the past year were eligible. A randomly selected control group consisting of patients taking CPA with normal sodium concentrations was also chosen. One hundred forty-five of 799 patients who had received CPA were included in the study.


RESULTS
The average daily dose of CPA was 425 +/- 207 mg (+/- SD). The incidence of hyponatremia associated with CPA was 7.1 percent (57/799 patients). The majority of patients were mildly hyponatremic (48/57 patients, 84 percent) with serum sodium concentrations between 130 and 134 mmol/L. The incidence of CPA-induced syndrome of inappropriate antidiuretic hormone was 2.1 percent. Concurrent angiotensin-converting enzyme (ACE) inhibitor use was identified as a risk factor; thiazide diuretic use was not.


CONCLUSIONS
The incidence of hyponatremia related to CPA use in elderly veterans is consistent with other reports in the literature. ACE inhibitors may be a predisposing factor for CPA-induced hyponatremia.
Hirokawa
C A
CA
Department of Veterans Affairs Medical Center, Long Beach, CA.
Gray
D R
DR
D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage; D002140:California / Q000453:epidemiology; D002747:Chlorpropamide / Q000009:adverse effects*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007010:Hyponatremia / Q000139:chemically induced* / Q000453:epidemiology; D007177:Inappropriate ADH Syndrome / Q000139:chemically induced* / Q000453:epidemiology; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D014728:Veterans
D000806:Angiotensin-Converting Enzyme Inhibitors; D002747:Chlorpropamide