정신과 입원환자의 다음증에 관한 연구

A Study on Polydipsia of Psychiatric Inpatients

Objects : We attempted to estimate the prevalence o f polydipsia in psychiatric inpatients in Seoul National Mental Hospital and to find out the identification method for polydipsic patients. We also compared the clinical and biological characteristics of polydipsic patients with those in nonpolydipsic patients. Methods & Results ： The following inclusion criteria were applied to the study subjects for estimating the prevalence of polydipsia among psychiatric inpatients at Seoul National Mental Hospital. 1) By staff report, that a objective clinical evidence of water intoxication during hospitalization was noted. 2) Three consecutive urine specific gravities were all less than 1.008 and also water intake was more than 3 liters per day. 3) Three consecutive urine specific gravities were all less than 1.008 and also serum sodium level was less than 135 mEq / L. By these inclusion criteria, we found 24 polydipsic patients among 634 hospitalized psychiatric inpatients, with the prevalence of 3.79%. Comparison of the clinical characteristics and biological determinants between 20 polydipsic and 20 nonpolydipsic patients produced the following results ： 1) No differences were found in duration of illness, dosage of neuroleptics, seizure history, electroconvulsive therapy history, smoking, use of medications other than neuroleptics, between the groups. 2) There was no difference in normalized diurnal weight gain. But polydipsic patients showed more water intake and lower urine specific gravities than nonpolydipsic ones. 3) Plasma antidiuretic hormone levels were within normal range and osmolalities were lower than normal range in polydipsic patients. But plasma antidiuretic hormone levels were higher than normal range and osmolalities were within normal range in nonpolydipsic patients. Conclusion ： The prevalence of the polydipsia was 3.79%. We suggest that staff report, urine specific gravity, serum sodium level, and oral water intake can be identification markers for polydipsia. Clincal characteristics such as duration of illness, dosage of neuroleptics, seizure history, electroconvulsive therapy history, smoking, and use of medications other than neuroleptics did not differ between polydipsic and nonpolydipsic patients. But biological determinants such as urine specific gravity, oral water intake, plasma antidiuretic hormone level, and osmolality differed beween the groups. Therefore these biological determinants could be adopted as biological markers for polydipsia.