門診病患微白蛋白尿與尿液中電解質排出量的關聯性

【研究背景】微白蛋白尿是高血壓及糖尿病患者一項危險因子，近年來被定義為發展心血管疾病及慢性腎臟疾病重要指標之一。例行性微白蛋白尿檢測對於高危險群患者是一項基礎性評估。尿液中電解質臨床重要性研究不多；高血壓及糖尿病患者容易有尿路結石情況發生。表示先前這些患者尿鈣排出增加。鎂離子缺乏常與糖尿病及其病發症有關。鎂離子缺乏是否由尿液中排出造成體內鎂離子過低目前仍未確定。此外，目前沒有臨床研究評估蛋白尿與尿液中電解質關聯性。本研究我們分析了高血壓與糖尿病患者微白蛋白尿盛行率，也評估蛋白尿與尿液中電解質如鈉、鈣及鎂的關聯性。【研究設計與方法】臨床試驗患者來自門診成人病患。患者被分成四組，分別為對照組、高血壓組、糖尿病腎功能正常組及糖尿病腎功能異常組。患者基本資料包括：性別、年齡、身體質量指數及血壓檢查及紀錄。我們記錄半年內兩次尿液微白蛋白尿及尿液中鈉、鉀、鈣及鎂離子平均值。【研究結果】試驗為期7個月，總共納入389名病患。其中在對照組有89名病患；高血壓組有77名病患；糖尿病腎功能正常組有130名病患及糖尿病腎功能異常組有84病患。病患平均年齡為57.8±12.3歲，身體質量質數值25.6±4.0公斤/平方公尺，收縮壓133±19毫米汞柱及舒張壓76±12毫米汞柱。研究顯示高血壓及糖尿病不管腎功能正常與否患者有較高微白蛋白尿排出。而且糖尿病腎功能異常組有最高微白蛋白尿排出量。除了糖尿病腎功能異常組有較少尿鈣排出之外，其它電解質排出量四組相似。在關聯性方面：所有患者尿鈣排出與微白蛋白尿呈負相關。對照組患者微白蛋白尿與尿鈣與鎂排出呈正相關。糖尿病組微白蛋白尿與尿鎂排出呈正相關。糖尿病腎功能異常患者微白蛋白尿與尿鈣排出呈負相關。【結論】高血壓及糖尿病組患者有明顯較高微白蛋白尿盛行率。糖尿腎功能異常組患者有較嚴重蛋白尿發生。糖尿病腎功能正常組患者蛋白尿與尿鎂排出明顯相關，糖尿病腎功能異常組蛋白尿與尿鈣排出減少有關。

關鍵字

高血壓；糖尿病；微白蛋白尿；電解質

並列摘要

【Background】 Microalbuminuria is a risk factor for patients with hypertension and diabetes mellitus patients. Recently, it has been identified as an important index for the development of cardiovascular and chronic renal disease. Routine check for the presence of microalbuminuria is included as one of the fundamental assessments of patients with high risk. The clinical significance of urinary electrolytes is less defined. Patients with hypertension and diabetic are prone to develop urolithiasis. Increased urinary calcium excretion has been denoted previously. Magnesium deficiency has been linked with complications of diabetes. Whether urinary loss contributes to low magnesium remains undetermined. Furthermore, is there any correlation between albuminuria and urinary electrolyte excretion has not been investigated. In the present study, we analyzed the prevalence microalbuminuria in patients with hypertension and diabetes. The relationship between albuminuria and urinary excretion of sodium, calcium and magnesium were also examined. 【Study design and material】 Adult patients from out-patient –clinics were enrolled for study. They were divided into four groups: control, hypertension, diabetes mellitus with normal renal function and diabetes mellitus with impaired renal function. Their demographic data including gender, age, body mass index (BMI) and blood pressure were reviewed and recorded. The amount of albuminuria and urinary sodium, potassium, calcium, and magnesium excretion were averaged from two collections during a half year period. 【Results】 During a study period of 7 months, a total of 389 adult patients were eigible for further analysis. Among them 89 patients were grouped as control; 77 patients were hypertensive; 130 patiens were diabetes with normal renal function and 84 patients were thoese with impaired renal function. Their mean age 57.8 ± 12.3 years and BMI was 25.6 ± 4.0 kg/m2; systolic pressure was 133 ± 19 mmHg and diastolic pressure 76 ± 12 mmHg. Our results revealed that hypertensives and diabetic patients (irrespective of their renal function) had a higher level of microalbuminuria than control group; furthermore, diabetic patients with impaired renal function had the greatest microalbuminuria. The urinary electrolyte excretions were similar among four groups except for that significantly lower calcium excretion was observed in diabetic with impaired renal function group. Correlation analysis revealed that there was a negative association between albuminuria and urinary calcium excretion in all groups. In control group, microalbuminuria was directly related to urinary calcium and magnesium excretion. A significant association was found between blood pressure and albuminuria in hypertensives. In diabetes, albuminuria was positively correlated with urinary magnesium excretion. A negative association was found between albuminuri and calcium excretion in diabetes with impaired renal function. 【Conclusion】 We conclude that the prevalence of microalbumniuria were significantly higher in patients with hypertension and diabetes. Diabetics with impaired renal function had more severe albuminuria. There was significant association between albuminuria and urinary magnesium excretion in diabetes with normal renal function, whereas, in diabetes with impaired renal function, albuminuria was associated with redcued urinary calcium excretion.