Clinical Features of Hyponatremia: Changes Related to Increasing Use of Thiazide-Combination Diuretics / 대한신장학회지

ABSTRACT

PURPOSE: In this study, the etiology and the change of clinical characteristics of hyponatremia, in relation to the increased used of thiazide diuretics, have been assessed. METHODS: To perform a retrospective cohort study, a total sum of 322 patients who have been admitted in a single tertiary referral hospital between 2004 and 2009, were included. RESULTS: The most common cause of hyponatremia was due to thiazide diuretics (37.6%). Among the 121 patients who suffered from thiazide induced hyponatremia, 60 (48.0%) patients took combination thiazide. The incidence of hyponatremia has shown a tendency to increase from 2004 to 2009 (trend test, p<0.001). The incidence of hyponatremia due to the use of combination types has also increased (trend test, p<0.001). Thiazide induced hyponatremia showed no difference when compared to hyponatremia due the other causes, except the fact that the portion of female patients was higher (73.6% vs 64.6%, p<0.001), mean age was older (74.7 vs 69.9 years-old, p<0.001), and incidence of cerebrovascular accident was also higher (19.8% vs 6.5%, p<0.001). CONCLUSION: The use of thiazide is increasing and hence thiazide-induced hyponatremia is also increasing. This is thought to be particularly related to the increase of thiazide-combined drugs. Thiazideinduced hyponatremia shows a higher incidence in old age, female sex and those who have a history of a cerebrovascular event. Hence more caution is needed when using thiazide diuretics as antihypertensives, and plasma sodium levels should be monitored carefully.