Goldman M B, Luchins D J, Robertson G L
Department of Psychiatry, Pritzker School of Medicine, University of Chicago.
N Engl J Med. 1988 Feb 18;318(7):397-403. doi: 10.1056/NEJM198802183180702.
Water intoxication is a serious problem in many patients with chronic psychiatric illness. In an effort to determine the mechanism of this disorder, we investigated the osmoregulation of water intake and antidiuretic function in psychiatric patients with polydipsia and hyponatremia and in matched controls with psychiatric illness but neither polydipsia nor hyponatremia. We found that a water load suppressed plasma osmolality and vasopressin and urine osmolality in both groups, but that urinary dilution and free water clearance were impaired in the patients with hyponatremia, even though plasma levels of vasopressin and solute clearance were similar in the two groups. Moreover, during water loading and infusion of hypertonic saline, the plasma level of vasopressin was higher at any given plasma osmolality in the test patients than in the controls, indicating a downward resetting of the osmostat. Patients' estimates of the amount of water they desired were shown to correlate significantly with the amount of water consumed and, at any given level of plasma osmolality, appeared to be higher in the test patients than in the controls. We conclude that psychiatric patients with polydipsia and hyponatremia have unexplained defects in urinary dilution, the osmoregulation of water intake, and the secretion of vasopressin.
水中毒在许多慢性精神疾病患者中是一个严重问题。为了确定这种病症的机制，我们研究了患有烦渴和低钠血症的精神病患者以及匹配的既无烦渴也无低钠血症的精神病对照组患者的水摄入渗透压调节和抗利尿功能。我们发现，两组中给予水负荷均会抑制血浆渗透压、血管加压素和尿渗透压，但低钠血症患者的尿液稀释和自由水清除受损，尽管两组的血管加压素血浆水平和溶质清除率相似。此外，在水负荷和输注高渗盐水期间，在任何给定的血浆渗透压下，测试患者的血管加压素血浆水平均高于对照组，表明渗透压调定点下调。患者对所需水量的估计显示与饮水量显著相关，并且在任何给定的血浆渗透压水平下，测试患者的估计值似乎高于对照组。我们得出结论，患有烦渴和低钠血症的精神病患者在尿液稀释、水摄入渗透压调节和血管加压素分泌方面存在无法解释的缺陷。
