1.Prognostic value of hyponatremia in heart failure patients: an analysis of the Clinical Characteristics and Outcomes in the Relation with Serum Sodium Level in Asian Patients Hospitalized for Heart Failure (COAST) study.
Byung Su YOO ; Jin Joo PARK ; Dong Ju CHOI ; Seok Min KANG ; Juey Jen HWANG ; Shing Jong LIN ; Ming Shien WEN ; Jian ZHANG ; Junbo GE
The Korean Journal of Internal Medicine 2015;30(4):460-470
BACKGROUND/AIMS: Hyponatremia is a well-known risk factor for poor outcomes in Western studies of heart failure (HF) patients. We evaluated the predictive value of hyponatremia in hospitalized Asian HF patients. METHODS: The Clinical Characteristics and Outcomes in the Relation with Serum Sodium Level in Asian Patients Hospitalized for Heart Failure (the COAST) study enrolled hospitalized patients with systolic HF (ejection fraction < 45%) at eight centers in South Korea, Taiwan, and China. The relationship between admission sodium level and clinical outcomes was analyzed in 1,470 patients. RESULTS: The mean admission sodium level was 138 +/- 4.7 mmol/L, and 247 patients (16.8%) had hyponatremia defined as Na+ < 135 mmol/L. The 12-month mortality was higher in hyponatremic patients (27.9% vs. 14.6%, p < 0.001), and hyponatremia was an independent predictor of 12-month mortality (hazard ratio, 1.72; 95% confidence interval, 1.12 to 2.65). During hospital admission, 57% of hyponatremic patients showed improvement without improvement in their clinical outcomes (p = 0.620). The proportion of patients with optimal medical treatment was only 26.5% and 44.2% at admission and discharge, respectively, defined as the combined use of angiotensin-converting-enzyme inhibitor/angiotensin receptor blocker and beta-blocker. Underuse of optimal medical treatment was more pronounced in hyponatremic patients. CONCLUSIONS: In hospitalized Asian HF patients, hyponatremia at admission is common and is an independent predictor of poor clinical outcome. Furthermore, hyponatremic patients receive less optimal medical treatment than their counterparts.
Aged
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Aged, 80 and over
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Asia/epidemiology
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*Asian Continental Ancestry Group
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Biomarkers/blood
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Cardiovascular Agents/therapeutic use
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Disease-Free Survival
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Female
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Guideline Adherence
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Healthcare Disparities
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Heart Failure/*diagnosis/drug therapy/ethnology/mortality/physiopathology
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*Hospitalization
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Humans
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Hyponatremia/blood/*diagnosis/drug therapy/ethnology/mortality
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Male
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Middle Aged
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Practice Guidelines as Topic
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Predictive Value of Tests
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Proportional Hazards Models
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Risk Factors
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Sodium/*blood
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Stroke Volume
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Time Factors
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Treatment Outcome