中风患者的低钾血症与钾排泄

Hypokalemia and potassium excretion in stroke patients.

作者信息

Gariballa S E, Robinson T G, Fotherby M D

机构信息

University Department of Medicine for the Elderly, Selly Oak Hospital, Birmingham, UK.

出版信息

J Am Geriatr Soc. 1997 Dec;45(12):1454-58. doi: 10.1111/j.1532-5415.1997.tb03195.x.

DOI:10.1111/j.1532-5415.1997.tb03195.x

PMID:9400554

Abstract

OBJECTIVES

To determine (1) the prevalence of hypokalemia (plasma potassium < or = 3.4 mmol/L) in a group of stroke patients in comparison with age- and sex-matched groups of patients having sustained a myocardial infarction or having mild hypertension and (2) the association between plasma potassium concentration and stroke outcome.

DESIGN

Observational study.

PARTICIPANTS

A total of 421 consecutive stroke patients admitted to a teaching hospital, 150 consecutive patients 50 years or older with myocardial infarction admitted to the hospitals Coronary Care Unit, and 161 out-patients 60 years or older with borderline and established hypertension.

MEASUREMENTS

All stroke and cardiac patients had plasma urea and electrolytes estimated within 2 hours of hospital admission; in the hypertensive group blood samples were taken in clinic. Stroke patients had blood pressure, stroke severity (Barthel score) and smoking status recorded. A sub-group of 61 stroke patients and all 79 hypertensive patients not taking antihypertensive medication had 24-hour urine electrolyte excretion measured. Outcome (independent, dependent, or dead) at 3 months post-stroke was established in 349 patients.

RESULTS

Hypokalemia occurred more frequently in stroke patients than in patients with myocardial infarction (84 (20%) vs 15 (10%), P = .008) or patients with hypertension (84 (20%) vs 13 (8%), P < .001), even when patients taking diuretics were excluded from analysis (56 (19%) vs 12 (9%) of cardiac group, P = .014 and 56 (19%) vs 4 (5%) of hypertensive group, P = .005, respectively). 24-hour urine excretion of potassium and the potassium:creatinine ratio was lower in stroke patients than in hypertensive patients (41 +/- 21 vs 62 +/- 25 mmol/24 hour, P = .001, 5.5 +/- 2.2 vs 7.4 +/- 2.6 mmol/24 hour, P = .001, respectively). On survival analysis, a lower plasma potassium on admission to hospital was associated with an increased chance of death, independent of age, stroke severity, history of hypertension, blood pressure level, or smoking history (hazard ratio 1.73 (95% CI: 1.03-2.9) for a 1 mmol/L lower plasma potassium concentration).

CONCLUSIONS

Hypokalemia post stroke is common and may be associated with a poor outcome.

摘要

目的

（1）确定一组中风患者低钾血症（血浆钾≤3.4 mmol/L）的患病率，并与年龄和性别匹配的心肌梗死患者组或轻度高血压患者组进行比较；（2）确定血浆钾浓度与中风预后之间的关联。

设计

观察性研究。

参与者

一家教学医院收治的421例连续中风患者、医院冠心病监护病房收治的150例年龄在50岁及以上的连续心肌梗死患者，以及161例年龄在60岁及以上的临界高血压和确诊高血压门诊患者。

测量指标

所有中风和心脏病患者在入院后2小时内测定血浆尿素和电解质；高血压组在门诊采集血样。记录中风患者的血压、中风严重程度（Barthel评分）和吸烟状况。61例中风患者和所有79例未服用抗高血压药物的高血压患者亚组测定24小时尿电解质排泄量。349例患者确定了中风后3个月的预后（独立、依赖或死亡）。

结果

中风患者低钾血症的发生率高于心肌梗死患者（84例（20%）对15例（10%），P = 0.008）或高血压患者（84例（20%）对13例（8%），P < 0.001），即使在分析中排除服用利尿剂的患者后也是如此（心脏组56例（19%）对12例（9%），P = 0.014；高血压组56例（19%）对4例（5%），P = 0.005）。中风患者的24小时尿钾排泄量和钾肌酐比值低于高血压患者（分别为41±21对62±25 mmol/24小时，P = 0.001；5.5±2.2对7.4±2.6 mmol/24小时，P = 0.001）。生存分析显示，入院时较低的血浆钾与死亡几率增加相关，与年龄、中风严重程度、高血压病史、血压水平或吸烟史无关（血浆钾浓度每降低1 mmol/L，风险比为1.73（95%CI：1.03 - 2.9））。