J Korean Med Sci.  2014 Sep;29(Suppl 2):S117-S122. 10.3346/jkms.2014.29.S2.S117.

Analysis of Correlation between 24-Hour Urinary Sodium and the Degree of Blood Pressure Control in Patients with Chronic Kidney Disease and Non-Chronic Kidney Disease

• Koo HS
• Kim YC
• Ahn SY
• Oh SW
• Kim S
• Chin HJ

• KMID: 2069802
• DOI: http://doi.org/10.3346/jkms.2014.29.S2.S117

Abstract

We investigated the association between 24-hr urinary sodium (24UNA) and adequacy of blood pressure (BP) control in patients with chronic kidney disease (CKD) and nonCKD. All data were collected retrospectively by accessing the electrical medical records in patients with 24-hr urine collection and serum creatinine. Enrolled 400 subjects were subgrouped by the amount of 24UNA, or CKD stage. The appropriate BP was defined as BP < 130/80 mmHg for subjects with proteinuria, and BP < 140/90 mmHg for subjects without proteinuria. The mean level of 24UNA was 166+/-76 mEq/day. The 24UNA group was an independently related factor to diastolic BP as a continuous variable. The rate of appropriate BP control in patients with proteinuria was highest in 24UNA <100 mEq/L (P=0.012). The odds to fail achievement of BP target in subjects with 24UNA> or =90 mEq/day was 2.441 (1.249-4.772, P=0.009) higher than that of 24UNA <90 mEq/day among participants with proteinuria. There was difference in the amount of 24UNA between CKD and non-CKD except each stage of CKD group. In conclusion, salt intake estimated by 24-hr urine sodium excretion is a risk factor to achieve appropriate BP control.

Keyword

Salt; Hypertension; Blood pressure; Renal insufficiency

MeSH Terms

Adult
Aged
Algorithms
Blood Pressure/*physiology
Creatine/blood
Demography
Female
Humans
Hypertension/complications
Male
Middle Aged
Odds Ratio
Proteinuria/complications
Renal Insufficiency, Chronic/complications/*pathology
Retrospective Studies
Risk Factors
Severity of Illness Index
Sodium, Dietary/*urine
Urine Specimen Collection
Creatine
Sodium, Dietary

Figure

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  Fig. 1 The estimated levels of blood pressures in 24UNA group adjusted with related factors (see Table 2) by ANCOVA test. *P value = 0.030 compared to group with 24 hr-urine sodium < 100 mEq/day. The bar means the 95% confidence interval of estimated value in each group.

• 

  Fig. 2 Frequency of BP<130/80 mmHg or<140/90 mmHg among all participants according to levels of 24-hr urine sodium.

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  Fig. 3 The prevalence of 24-hr urine sodium < 100 mEq in each group of chronic kidney disease (CKD). *P < 0.05 compared to Non-CKD group.

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  Fig. 4 The estimated value of 24-hr urine sodium in CKD groups adjusted with related factors, such as history of cancer, DBP, BMI, glucose, uric acid, serum albumin stratified with 3.0 g/dL, and 24-hr urine protein, by ANCOVA test. The bar means the 95% confidence interval of estimated value in each group.

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