Lip G Y, Beevers M, Beevers D G
University Department of Medicine, City Hospital, Birmingham, UK.
J Hypertens. 2000 Jan;18(1):97-101. doi: 10.1097/00004872-200018010-00014.
There has been speculation whether serum uric acid levels are an independent prognostic factor in patients with hypertension.
To investigate the clinical associations and prognostic value of serum urate in patients with malignant phase hypertension (MHT), by comparing clinical features in patients with serum urate levels above and below the median levels for this population, and secondly, by performing a survival analysis in these patients.
Review of the data on 153 patients (98 males; mean age 50.3 years, SD 13.5) with MHT on the west Birmingham MHT register. Median uric acid levels in this population was 0.41 mmol/l (6.9 mg/dl), with an interquartile range of 0.34-0.50 mmol/l (5.7-8.4 mg/dl). Clinical characteristics of patients with a serum urate <0.41mmol/1 (group 1) were compared to those with levels above the median (0.41 mmol/l, group 2).
Mean duration of follow-up was similar in both groups. The mean diastolic blood pressure at presentation and both mean systolic and diastolic blood pressures at follow-up were significantly higher in group 2 (that is, those with high serum urate levels) (unpaired t test, P= 0.039). There was also more renal dysfunction in group 2 patients with MHT, with higher mean serum urea and creatinine levels, both at presentation and at follow-up (unpaired t test, P< 0.01). The commonest causes of death were myocardial infarction (n = 7), heart failure (n = 4), stroke (n = 10) and renal failure (n = 5). There was no difference in mean survival duration between groups 1 and 2 (Kaplan-Meier, 64.6 versus 66.8 months; log-rank test, P= 0.519). Serum urate levels also did not predict the rise in serum creatinine levels (log-rank test, P= 0.84) or urea (P= 0.4033) amongst these patients. Using a multivariate Cox proportional hazards analysis, the only independent predictors of outcomes (death or the need for dialysis) were age (P = 0.007) and serum creatinine levels at presentation (P = 0.0046).
Our analysis of a large series of patients with MHT shows that those with high urate levels had higher diastolic blood pressures and greater renal impairment at baseline. At follow-up, patients with median serum urate >0.41 mmol/l showed a greater deterioration in renal function and higher blood pressures, but no significant difference in survival. Serum urate levels also do not appear to be predictive of the deterioration in renal function or overall survival in patients with MHT.
血清尿酸水平是否为高血压患者的独立预后因素一直存在争议。
通过比较血清尿酸水平高于和低于该人群中位数水平的患者的临床特征，以及对这些患者进行生存分析，探讨血清尿酸盐在恶性高血压（MHT）患者中的临床关联和预后价值。
回顾西伯明翰MHT登记册上153例MHT患者（98例男性；平均年龄50.3岁，标准差13.5）的数据。该人群的尿酸中位数水平为0.41 mmol/l（6.9 mg/dl），四分位间距为0.34 - 0.50 mmol/l（5.7 - 8.4 mg/dl）。将血清尿酸<0.41mmol/1的患者（第1组）与高于中位数水平（0.41 mmol/l，第2组）的患者的临床特征进行比较。
两组的平均随访时间相似。第2组（即血清尿酸水平高者）就诊时的平均舒张压以及随访时的平均收缩压和舒张压均显著更高（未配对t检验，P = 0.039）。第2组MHT患者的肾功能损害也更严重，就诊时和随访时的平均血清尿素和肌酐水平均更高（未配对t检验，P<0.01）。最常见的死亡原因是心肌梗死（n = 7）、心力衰竭（n = 4）、中风（n = 10）和肾衰竭（n = 5）。第1组和第2组之间的平均生存时间无差异（Kaplan-Meier分析，64.6个月对66.8个月；对数秩检验，P = 0.519）。血清尿酸水平也不能预测这些患者血清肌酐水平（对数秩检验，P = 0.84）或尿素水平（P = 0.4033）的升高。使用多变量Cox比例风险分析，结果（死亡或需要透析）的唯一独立预测因素是年龄（P = 0.007）和就诊时的血清肌酐水平（P = 0.0046）。
我们对大量MHT患者的分析表明，尿酸水平高者在基线时舒张压更高，肾功能损害更严重。随访时，血清尿酸中位数>0.41 mmol/l的患者肾功能恶化更明显，血压更高，但生存无显著差异。血清尿酸水平似乎也不能预测MHT患者的肾功能恶化或总体生存情况。
