Patterns of urinary excretion among patients with self-induced water intoxication and psychosis

Development of diagnostic criteria and severity scale for polydipsia: A systematic literature review and well-experienced clinicians' consensus

Despite the clinical importance of polydipsia, no diagnostic criteria or severity scales that comprehensively assess this condition are available. Thus, we aimed to develop diagnostic criteria and a severity scale for polydipsia based on a systematic review and well-experienced clinicians' consensus. We performed a systematic review, identified 27 studies related to diagnostic criteria or severity classification for polydipsia, and extracted items used to assess polydipsia in these studies. Ten well-experienced clinicians-5 psychiatrists and 5 nurses-participated in the Delphi method. They evaluated 39 items extracted based on the results of the systematic review regarding (1) their necessity in diagnosing and assessing the severity of polydipsia, and (2) their relative importance rated on 7-point scale among the items included in the severity scale. The Polydipsia Diagnostic Criteria (PDC) included 4 essential items-excessive drinking, low serum sodium level or low serum osmolality, abnormal normalized diurnal weight gain, and low urine specific gravity-based on consensus reached using the Delphi method. The Polydipsia Severity Scale (PSS) included 13 items with a maximum score of 59. The first diagnostic criteria and symptom scale for polydipsia were developed based on the findings of a systematic review and well-experienced clinicians' consensus.

Association analysis between the C-1291G polymorphism in the promoter region of the adrenergic alpha2A receptor gene and polydipsia in schizophrenia

Several lines of studies have shown the existence of an important inhibitory mechanism for the control of water intake involving adrenergic alpha2A receptors (ADRA2A). A human study using patients with schizophrenia demonstrated an exacerbation of polydipsia by the administration of clonidine, an ADRA2A-agonist, and a relief of polydipsia by mianserin, an ADRA2A-antagonist, suggesting the involvement of the central adrenergic system in the drinking behavior of patients with schizophrenia. Based on these findings we examined a possible association between the C-1291G polymorphism in the promoter region of the ADRA2A gene and polydipsia in schizophrenia using a Japanese case-control sample. Our sample includes 348 patients with schizophrenia (DSM-IV) (84 with polydipsia and 264 without polydipsia). No significant association between the ADRA2A C-1291G polymorphism and polydipsia was found. Our result suggests that the ADRA2A C-1291G polymorphism may not confer susceptibility to polydipsia in schizophrenia in our sample. Further studies with larger samples are warranted.

The orexin 1 receptor (HCRTR1) gene as a susceptibility gene contributing to polydipsia-hyponatremia in schizophrenia

The underlying pathophysiology of primary polydipsia in schizophrenia (SCZ) is poorly understood. Our previous study, however, suggested that this condition may have a genetic component [Shinkai et al 2003 Am J Med Genet 119B 7-12]. Orexins, also called hypocretins, play an important role in feeding and drinking behavior. Administration of orexin in rats has been shown to induce increased water intake with a longer-lasting effect than angiotensin II, which is also known as a potent dipsogen. Meerabux et al. [2005 Biol Psychiatry 58 401-407] reported an association between the 408Val allele of the orexin 1 receptor (HCRTR1) gene and polydipsia-hyponatremia in a sample of Japanese patients with SCZ. In the present study, we attempted to replicate the findings of Meerabux et al. in an independent Japanese case-control sample. Our sample included 312 patients with SCZ (DSM-IV) (65 with polydipsia and 247 without polydipsia). We also observed an association between the HCRTR1 Ile408Val polymorphism and polydipsia (genotype distribution: chi2 = 9.85, df = 2, P = 0.007). Meerabux et al. (2005) previously demonstrated an association between the 408Val allele of the HCRTR1 gene and polydipsia. In contrast with Meerabux et al. study, we found that the 408Ile allele was associated with polydipsia in our sample (chi2 = 8.00, df = 1, P = 0.0047; OR = 0.53; 95%CI = 0.34-0.83). How either allele contributes to the development of polydipsia in SCZ is unclear at this stage. It is possible that Ile408Val polymorphism is a non-functional marker that lies in linkage disequilibrium with an as-yet undetected functional variant. In any case, our results support the hypothesis that the HCRTR1 Ile408Val polymorphism may confer susceptibility to polydipsia in SCZ. Further studies examining the association between the orexin system and polydipsia in SCZ are warranted.

Autopsy case report of a rare acute iatrogenic water intoxication with a review of the literature

This paper reports a rare autopsy case, a 21-years old healthy female worker, who died of acute iatrogenic water intoxication after she had swallowed powder scraped off 17 matches in an apparent suicide attempt. Gastric lavage was performed as she was wrongly considered to have taken poison containing phosphorus. She was given 7.8 1 water within 2 h. The pathological findings and 16 cases from the literature between 1978-1994 are reviewed.

Serum sodium stabilizing effect of enalapril after standard water load in a patient with a history of self-induced water intoxication

1. A 21 day prospective placebo controlled double blind cross over trial of enalapril was studied in a normonatremic patient with a known history of SIWI. 2. At the end of each prophylactic treatment, the patient was challenged with a water load of 20 ml/kg. 3. The mean serum sodium of 140.111 mmol/L on prophylactic enalapril was significantly higher than the 137.6 mmol/L on placebo (p = 0.0015). 4. After a water load, the mean serum sodium on enalapril was 137.6 mmol/L, compared to 133.833 mmol/L (p = 0.0015) on placebo.

Abuse-related posttraumatic stress disorder: evidence for chronic neuroendocrine activation in women

The following study tested the hypothesis that women with post-traumatic stress disorder (PTSD) related to childhood sexual abuse would display elevated norepinephrine-to-cortisol ratios similar to that found in male combat veterans diagnosed with PTSD. Twenty-four-hour urine samples were collected from 28 women: 11 women with PTSD who experienced childhood sexual abuse (PTSD+), 8 women who experienced childhood sexual abuse without PTSD (PTSD-), and 9 nonabused controls. All urine samples were tested for creatinine, total catecholamines, free-cortisol, and 17-ketosteroid levels. Psychological testing validated that the PTSD+ group was significantly elevated on all three subscales of the Impact of Events Scale. Both abused groups (PTSD+ and PTSD-) showed a tendency for polyuria, and the PTSD+ group showed a tendency towards obesity. Thus, neuroendocrine values (micrograms/day) were adjusted by creatinine clearance rates (creatinine mg/day/kg body weight). The corrected values indicated that the PTSD+ group had significantly elevated daily levels of norepinephrine, epinephrine, dopamine, and cortisol. However, because of the parallel elevation in cortisol, the norepinephrine-to-cortisol ratio was not significantly elevated in the PTSD+ diagnosed women in contrast to the findings reported for male PTSD patients. This discrepancy may reflect an important gender difference, an interaction between gender and age at onset of the traumatic experience (childhood abuse in females vs. combat experience in young adult males), or physiological variation related to phase of the disorder.

Hyper- and hyponatremia among geropsychiatric inpatients

We report our experience treating 14 elderly psychiatric patients with altered sodium states. Hypernatremia occurs more commonly among elderly psychiatric patients than among their younger counterparts, and elderly hypernatremic psychiatric patients suffer most commonly from dementia. Dilutional hyponatremia is less common and less severe among elderly schizophrenic patients compared with younger patients with schizophrenia. Central nervous system changes induced by altered sodium states among elderly psychiatric patients are sufficiently similar whether hyper- or hyponatremia is present; therefore, the clinician must not wait for specific features to develop, but must quickly measure serum sodium concentration in elderly psychiatric patients with altered mental states. Treatment of hypernatremia involves rehydration with normal saline or hypotonic solutions, and treatment of dilutional hyponatremia largely involves fluid restriction.

An epidemiological study on hyponatremia in psychiatric patients in mental hospitals in Nara Prefecture

Hyponatremia occurs often in mental illness. The frequency was not noticed because of the uncharacteristic symptoms of mild hyponatremia. Of the 1,114 psychiatric inpatients retrospectively surveyed, 10.5% had hyponatremia. Not only patients with schizophrenia, but also patients with other mental illness, especially with epilepsy, having hyponatremia were confirmed. An early onset, a long duration of psychiatric disorder and a prolonged admission were statistically significant factors. Nicotine abuse was not a significant factor. It was suggested that the pathogenesis of hyponatremia in psychiatric patients might be involved in a chronic course of psychiatric disorders and poor response to psychopharmacotherapy.

Functional obstructive uropathy: a significant factor in the hyponatremia of psychogenic polydipsia?

A case is presented of psychogenic polydipsia with hyponatremia. Prolonged observation of the patient revealed that episodes of hyponatremia correlated best with bladder failure and were promptly corrected by bladder catheterization. Bladder catheterization for underlying functional obstructive uropathy should be considered early in the treatment of patients with psychogenic polydipsia and hyponatremia.

A review of disorders of water homeostasis in psychiatric patients

Disorders of water homeostasis are common in psychiatric patients and include compulsive water drinking, the syndrome of inappropriate antidiuretic hormone secretion (SIADH), and the syndrome of self-induced water intoxication (SIWI). Although water intoxication was recognized nearly 70 years ago, the physiological basis of these disorders of water metabolism still remains elusive. This review will provide a historical overview, critique current studies on compulsive water drinking and SIWI, discuss possible etiologies, and present current approaches to treatment of these disorders. Because of the complexity of the subject, a review of normal water homeostasis and the SIADH will be included.

Polydipsia in the chronically mentally ill: a review

Polydipsia, or excessive intake of water, is reviewed in the chronically mentally ill from a nursing perspective. The purpose of this article is to review research related to excessive water ingestion, the magnitude and types of problems that these patients experience, and the treatment interventions reported. Future research and practice should focus on understanding the patient's experience of polydipsia and how it relates to the patient's level of functioning, testing assessment tools, and determining appropriate interventions.

Failure of antipsychotic drug dose to explain abnormal diurnal weight gain among 129 chronically psychotic inpatients

1. The diurnal weight gain was found to be abnormal among 129 chronically psychotic inpatients. 2. The patients were weighed at 7 a.m. and 4 p.m. weekly for three weeks. We normalized the diurnal weight gain (NDWG) as a percentage by subtracting the 7 a.m. weight from the 4 p.m. weight, multiplying the difference by 100, and then dividing the result by the 7 a.m. weight. 3. NDWG was 2.2 +/- 1.5 percent for 87 male patients compared (p less than .0001) with .53 +/- .41 for 14 male controls. 4. NDWG was 1.8 +/- 1.0 percent for 42 female patients compared (p less than .0001) with .49 +/- .30 for 15 female controls. 5. Seventy percent of male and female patients had NDWG values greater than two standard deviations above the mean values of controls. 6. Differences in age, sex, morning weight, antipsychotic drugs, lithium, carbamazepine, phenytoin, blood pressure, and pulse did not explain these findings.

Diurnal weight gain as a predictor of serum sodium concentration in patients with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome)

Ten male patients (mean age 37.3 +/- 6.4 years) with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome) underwent measurement of weight, sitting and standing blood pressure, and serum sodium concentration at 7 a.m. and 4 p.m. weekly for 8 consecutive weeks. Blood pressure was higher in the afternoon than in the morning. The diurnal decrease in serum sodium (141.4 +/- 2.8 to 134.2 +/- 4.8 mEq/l) was associated with a diurnal increase in weight (78.4 +/- 9.7 to 80.0 +/- 10.3 kg). When the weight increase was normalized by dividing by 7 a.m. weight (NDWG), the following relationship evolved: diurnal serum sodium decrease = 3.060 + [201.728 x NDWG]. Therefore, NDWG accounted for 63.1% of the variability of serum sodium. Using the known relationship of plasma water, total body water, and total body weight, we calculated that antidiuresis (afternoon weight gain) accounted for 62.5% of afternoon hyponatremia. Thus, two separate methods of calculating the relationship between antidiuresis and hyponatremia provided remarkably similar findings. We derived a table to predict 4 p.m. serum sodium values based on 7 a.m. weight, 7 a.m. serum sodium, and 4 p.m. weight.

Diurnal variation in water homeostasis among schizophrenic patients subject to water intoxication

Among seven schizophrenic patients subject to water intoxication (six men and one woman, mean age 39.1 +/- 6.9 years), we measured serum sodium, plasma arginine vasopressin, and urine osmolality at 7 a.m. and 4 p.m. on eight consecutive Thursdays. On the days of greatest diurnal change in serum sodium, the 7 a.m. serum sodium was 141.1 +/- 1.8 mEq/l and the 4 p.m. value was 129.9 +/- 3.2 mEq/l. Plasma vasopressin also tended to be lower at 4 p.m. but, in many cases, was inadequately suppressed for the level of hyponatremia. The urine was dilute at both 7 a.m. and 4 p.m. and mean urine osmolality did not differ at the two times. In three patients, urine osmolality was consistently subnormal relative to plasma vasopressin at both 7 a.m. and 4 p.m. This abnormality was consistent with nephrogenic diabetes insipidus secondary to lithium and, possibly, phenytoin which the patients received to protect them against hyponatremia. We conclude that the combination of polydipsia and abnormal osmoregulation of vasopressin secretion contributes importantly to the afternoon hyponatremia found in schizophrenic patients subject to water intoxication.

Polydipsia in chronic psychiatric patients. Body weight and plasma sodium

Eight chronic psychiatric in-patients with polydipsia, and polyuria, up to 22 litres per 24 hours, were studied by frequent timed body weight and urine volume measurements, and episodic plasma electrolyte estimations. During the day they all showed irregular water retention, with hyponatremia in proportion to the weight gain. During the night they always lost water and weight, returning to their individual lowest weights and to normal plasma sodium. Measurement of weight in chronic psychiatric patients can be used to identify patients with significant polydipsia, to monitor those with the disorder and permit targeted fluid restriction, and to assess the efficacy of treatment procedures such as medication.

The use of demeclocycline in the treatment of patients with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome)

Eight patients (7 men and 1 woman, mean age 43.1 +/- 8.9 years) with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome) underwent treatment with demeclocycline in an effort to normalize serum sodium levels and thereby protect the PIP patients against complications including hyponatremic seizures and coma. There tended to be an improvement (p = .080) in early morning serum sodium following treatment with demeclocycline (baseline 132.6 +/- SD 3.3 and treatment serum sodium 134.8 +/- SD 3.3 mEq/1). At the same time, there was an increase (p = .043) in urinary specific gravity following treatment with demeclocycline (baseline 1.0047 +/- SD .0029 and treatment urinary specific gravity 1.0063 +/- SD .0026). Clinical indications for and potential mechanisms of action of demeclocycline treatment in the PIP syndrome are discussed.

Diurnal variation of urinary excretion for patients with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome)

Ten patients [8 men and 2 women, mean age (SD) 37.6 +/- 6.5 years] with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome) underwent serial determinations at 6:00 AM, 12 noon, 6:00 PM, and 12 midnight of levels of urinary creatinine concentration (UCR), urinary specific gravity (SPGR), and urinary osmolality (UOSM) on 8 consecutive Thursdays. Diurnal variation (p less than 0.015) was present in the case of each parameter of urinary excretion (UCR, SPGR, and UOSM). These three parameters remained very low throughout the day (mean UCR 19.0 mg/dl, mean SPGR 1.0033, and mean UOSM 112.6 mosmol/kg), which is consistent with severe and persistent hyposthenuria, and each parameter correlated well with the other two parameters (r between 0.78 and 0.93, p less than 0.001). The 6:00 PM (UC6PM) value for UCR correlated best with the daily mean UCR (UCM), providing the simple linear regression UCM = 0.7615 X UC6PM + 6.1503 (r = 0.912, p = 0.0005) for the 10 PIP patients. Twenty-four-hour urinary volume (24UV) could then be estimated using UCM and values of 17.5 and 12.5 mg creatinine/kg body weight for male and female PIP patients, respectively, to calculate the daily urinary excretion of urinary creatinine. The group mean 24UV was 6963 ml, with a range of 4934-9884 ml. We hope that information about the diurnal variation of urinary excretion (21.6%, 20.5%, 27.4%, and 30.4% of 24UV excreted in consecutive quartiles commencing with the 12 midnight to 6:00 AM quartile), coupled with the utilization of the equation UCM = 0.7615 X UC6PM + 6.1503 (r = 0.912, p = 0.0005) to estimate UCM as an index of 24UV in the PIP syndrome, will provide tools to better elucidate the relationship between psychosis and water dysregulation.

Psychogenic polydipsia and water intoxication--concepts that have failed

Ten patients (8 men, 2 women; mean age 38.7 +/- 8.1 years), 7 of whom had schizophrenic disorders and 3 of whom had bipolar disorder (manic-depressive illness), manifested psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome). The relationship between serum sodium and urinary water excretion among the 10 PIP patients is described in detail. The success of lithium in improving serum sodium levels and in decreasing urinary water excretion among the three PIP patients with bipolar disorder and the failure of changes in urinary water excretion to explain changes in serum sodium levels among the 10 PIP patients argue against "psychogenesis" as the explanation for the polydipsia and excessive water intake as the sole explanation for hyponatremia or complications ascribed to water intoxication.