Correlation of 24-Hour Urine Sodium, Potassium and Calcium Measurements with Spot Urine

Abstract

In this study, we analyzed the correlation of sodium(Na), potassium(K) and calcium(Ca) amounts with spot urine(SU) and 24-hour urine(24-HU) collected as 8-hour portions. 21 hypertensive patients and 21 normotensive individuals were enrolled in the study. Na, K and Ca were studied in three sequential 8-hour urine samples and with the sum of three, 24-HU samples of the cases. Sodium/creatinine, potassium/creatinine, and calcium/creatinine were studied in fasting SU and serum Na, K and creatinine were studied. A significant correlation was found between the SU sodium/creatinine ratio and the Na amount in each 8-hour urine collections, and the Na amount in the 24-hour urine in hypertensive patients, the control group, and when all patients were evaluated together. When all group were evaluated together for Ca, a significant correlation was determined between the SU calcium/creatinine ratio and the Ca amount in all three 8-hour urine collections. The Na amount in the 24-HU may be estimated both with the SU Na/creatinine ratio and the 8-hour urine collection; SU does not have clinical significance for potassium. However, it may be estimated with 8-hour urine collections; SU may help roughly for calcium, and the collected urine gives higher correlation coefficients.

Keywords

• Electrolyte excretion, 24-hour urine, spot urine

Correlation of 24-Hour Urine Sodium, Potassium and Calcium Measurements with Spot Urine

Öz

Bu çalışmada spot idrarda sodyum, potasyum ve kalsiyum miktarı ile 24 saatlik idrar miktarlarının korelasyonunu araştırdık. Çalışmaya 21 hipertansif hasta ve kontrol grubu olarak 21 normotansif birey alındı. Olguların ardışık üç 8 saatlik porsiyon idrarında Na, K, Ca çalışıldı. Ayrıca 8’er saatlik üç porsiyon idrar toplamanın ardından sabah aç iken alınan spot idrarda sodyum/kreatinin, potasyum/kreatinin, kalsiyum/kreatinin ve serumda da sodyum, potasyum, kreatinin çalışıldı. Sekizer saatlik biriktirilmiş idrarlar ve spot idrar ile 24 saatlik idrardaki Na miktarının korelasyon analizinde; spot idrar, birinci ve üçüncü 8 saatlik porsiyon idrar sodyum/kreatinin oranı ile 24 saatlik idrarda ölçülen sodyum miktarı arasında anlamlı bir korelasyon saptandı. Kontrol grubu ve hipertansiyon grubu birlikte değerlendirildiğinde, 24 saatlik sodyum miktarı ile spot idrar sodyum/kreatinin oranı ve birinci, ikinci ve üçüncü 8 saatlik biriktirilmiş idrardaki sodyum atılımı arasında anlamlı korelasyon mevcuttu. Kalsiyum açısından tüm gruplar birlikte değerlendirildiğinde spot idrar kalsiyum /kretainin oranı ile her üç sekizer saatlik biriktirilmiş idrardaki kalsiyum miktarı arasında anlamlı korelasyon saptandı. Sabah alınan spot idrar örneğinde sodyum/kreatinin ve sekizer saatlik biriktirilmiş idrardaki sodyum miktarı ile 24 saatlik idrardaki sodyum miktarı tahmin edilebilir .Spot idrardaki potasyum miktarının miktarının klinik anlamı yoktur. Spot idrardaki kalsiyum miktarı kabaca günlük kalsiyum atılımını gösterir

Anahtar Kelimeler

• Elektrolit salınımı, 24 saatlik idrar, spot idrar

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