Sodium-induced hyperhydration decreases urine output and improves fluid balance compared with glycerol- and water-induced hyperhydration.

Before 2010, which is the year the World Anti-Doping Agency banned its use, glycerol was commonly used by athletes for hyperhydration purposes. Through its effect on osmoreceptors, we believe that sodium could prove a viable alternative to glycerol as a hyperhydrating agent. Therefore, this study compared the effects of sodium-induced hyperhydration (SIH), glycerol-induced hyperhydration (GIH) and water-induced hyperhydration (WIH) on fluid balance responses. Using a randomized, double-blind and counterbalanced protocol, 17 men (21 ± 3 years, 64 ± 6 kg fat-free mass (FFM)) underwent three 3-h hyperhydration protocols during which they ingested, over the first 60-min period, 30 mL/kg FFM of water with (i) an artificial sweetener (WIH); (ii) an artificial sweetener + 7.45 g/L of table salt (SIH); or (iii) an artificial sweetener + 1.4 g glycerol/kg FFM (GIH). Changes in body weight (BW), urine production, fluid retention, hemoglobin, hematocrit, plasma volume, and perceptual variables were monitored throughout the 3-h trials. After 3 h, SIH was associated with significantly (p < 0.05) lower hemoglobin, hematocrit (SIH: 43.1% ± 2.8%; GIH: 44.9% ± 2.4%), and urine production, as well as greater BW, fluid retention (SIH: 1144 ± 294 mL; GIH: 795 ± 337 mL), and plasma volume (SIH: 11.9% ± 12.0%; GIH: 4.0% ± 6.0%) gains, compared with GIH and WIH. No significant differences in heart rate or abdominal discomfort were observed between treatments. In conclusion, our results indicate that SIH is a superior hyperhydrating technique than, and proves to be a worthwhile alternative to, GIH.

Urinary excretion half life of trichloroacetic acid as a biomarker of exposure to chlorinated drinking water disinfection by-products.

AIMS: To measure accurately urinary elimination half life of trichloroacetic acid (TCAA). METHODS: A longitudinal pilot exposure/intervention study measured the elimination half life of TCAA in urine. Beverage consumption was limited to a public water supply and bottled water of known TCAA concentration, and ingestion volume was managed. The five participants limited fluid consumption to only the water provided. Consumption journals were kept by each participant and their daily first morning urine (FMU) samples were analysed for TCAA and creatinine. TCAA elimination half life curves were generated from a two week washout period using TCAA-free bottled water. RESULTS: Individual elimination half lives ranged from 2.1 to 6.3 days, for single compartment exponential decay, the model which fit the data. CONCLUSION: Urinary TCAA is persistent enough to be viable as a biomarker of medium term (days) exposure to drinking water TCAA ingestion within a range of realistic concentrations.

Effects of clonidine in schizophrenic patients with primary polydipsia: three single case studies.

A pilot study was conducted in schizophrenic patients with primary polydipsia to determine the tolerability of adding clonidine to an existing antipsychotic drug regimen and to seek evidence of an antidipsic effect. Three patients with chronic schizophrenia and primary polydipsia underwent open controlled prospective trials of treatment with clonidine in doses of up to 800 microg/day. The trials lasted from 2 to 5 months each, and analysis of variance was used to test for changes in dependent variables on a case-by-case basis. Blood pressure and pulse declined significantly in a dose-dependent manner, but fluid intake, as assessed by measurements of weight and 24-h urine volume, was not affected. Hypotension and bradycardia limited the extent to which the dose of clonidine could be increased. The lack of evident effect of clonidine on polydipsia in this small sample and the inconsistent results of two other recent studies of clonidine in patients with schizophrenia and primary polydipsia provide little overall support for the effectiveness of clonidine treatment in primary polydipsia associated with schizophrenia.

The urine/plasma electrolyte ratio: a predictive guide to water restriction.

Patients with hypotonic hyponatremia are encountered commonly in the general practice of medicine. Nearly all strategies for the management of subacute or chronic hyponatremia call for some amount of water restriction. The considerations for such a prescription have not been addressed in the literature. We describe therefore a simple approach grounded in the physiology of electrolyte-free water clearance that can be used at the bedside.

Absence of changes in antidiuretic hormone, angiotensin II, and atrial natriuretic peptide with clozapine treatment of polydipsia-hyponatremia: 2 case reports.

BACKGROUND: Polydipsia-hyponatremia is a poorly understood disorder that causes considerable mortality and morbidity. Hyponatremia in polydipsia-hyponatremia has been attributed to disturbances in antidiuretic hormone (ADH) function. Improvements in polydipsia-hyponatremia during clozapine treatment offered the chance to see if levels of ADH and other hormones associated with osmoregulation changed with improvement in biochemical and clinical measures of polydipsia-hyponatremia. METHOD: In this preliminary, longitudinal study, we studied 2 male schizophrenic patients (DSM-III-R) who had polydipsia-hyponatremia. Measures were (1) biochemical and clinical: serum sodium and osmolality, urine osmolality and specific gravity, normalized diurnal weight gain, and estimated urine volume and (2) endocrine: ADH, angiotensin II, atrial natriuretic peptide, and prolactin. Measures were collected during 2 months of baseline (typical neuroleptic) and 6 months of clozapine treatment. RESULTS: Single-case statistical procedures showed significant changes in sodium levels (a.m. and p.m.), estimated urine volume, and a.m. urine specific gravity in both patients and significantly decreased diurnal weight gain in 1 patient. Both serum and urine osmolality showed improvement, but values did not reach statistical significance. Low baseline ADH levels persisted through 6 months of clozapine treatment and showed no changes in the context of improvements in serum sodium and osmolality. No significant changes were seen in levels of angiotensin II and atrial natriuretic peptide. CONCLUSION: Given the limitations of this study, there is some evidence to suggest that the improvements in serum sodium and osmolality during clozapine treatment of polydipsia-hyponatremia may not be related to serum levels of ADH, although altered ADH receptor function cannot be ruled out. These data need to be extended in larger samples.

Polydipsia and water intoxication in psychiatric patients: a review of the epidemiological literature.

Polydipsia among chronic psychiatric patients is poorly understood and underdiagnosed. It may have three stages: simple polydipsia, polydipsia with water intoxication, and physical complications. Epidemiological surveys have used staff reports and polyuria measures to identify polydipsic patients. Water intoxication has been screened by chart review, weight, or serum sodium data. According to these surveys, polydipsia, not explained by medically induced polyuria, may be present in more than 20% of chronic inpatients. Up to 5% of chronic inpatients had episodes of water intoxication although mild cases may have been missed. Single time point surveys show that 29% of polydipsic patients had presented water intoxication. Methodologically limited clinical studies suggest that polydipsia with water intoxication rather than simple polydipsia may be associated with poor prognosis in schizophrenia. Epidemiological surveys found polydipsia with water intoxication to be associated with chronicity, schizophrenia, smoking, some medications, male gender, and white race. New pathophysiological models need to elucidate these findings.

Urinary arginine vasopressin (AVP) measurement in children: water deprivation test incorporating urinary AVP.

The value of a water deprivation test incorporating urinary arginine vasopressin (AVP) measurement was investigated in 13 patients with polydipsia and/or polyuria (complete central diabetes insipidus [CCDI] in four; incomplete central diabetes insipidus [ICDI] in five; secondary nephrogenic diabetes insipidus [NDI] in three; compulsive water drinking [CWD] in one) and a group of 25 control subjects (C). Urine samples were collected after water deprivation during sleep and the urinary osmolalities and AVP concentrations were measured. Analysis of the results of 104 urine samples from the 25 control subjects demonstrated a close correlation between urinary osmolality and AVP (r = 0.89, P < 0.001). After water deprivation during sleep, the respective mean maximal urinary osmolalities and AVP concentrations were: 127.4 +/- 34.4 mOsm/kg and 1.1 +/- 0.5 pg/mL in the patients with CCDI (14 samples, four children); 410.3 +/- 101.8 and 6.1 +/- 3.5 in those with ICDI (16 samples, five children); 348.7 +/- 71.2 and 100 +/- 45.1 in those with NDI (nine samples, three children); 541.5 +/- 143.5 and 43.6 +/- 33.2 in the patient with CWD (two samples, one child) and 898.8 +/- 186.3 and 97.4 +/- 50.4 in group C (54 samples, 18 children). Furthermore, the urinary AVP level relative to the osmolality in each patient varied depending on the AVP secretion status and renal concentrating ability. Each patient, except the one with CWD, could be discriminated from the normal subjects using this test. It seems that this test is easy to perform and useful for diagnosis and follow-up of patients with partial/complete posterior pituitary function defects and those with renal concentration impairment.

A program for water-intoxicated patients at a state hospital.

During normal circumstances, individuals have a delicate balance of water requirement and water intake. If the balance of water is altered, electrolyte imbalance can occur. If fluid intake continues uncurbed, an extreme condition may result known as self-induced water intoxication and psychoses. If untreated, complications may develop, including dilated and hypotonic bowel and bladder, hydronephrosis, renal failure, congestive heart failure, mild confusion, acute delirium, seizures, coma, and death. The ongoing problem of water intoxication presents a modern day nursing challenge to psychiatric nurses. The present study monitors nine chronically ill patients in a special program for water intoxication involving control and monitoring and a psychoeducational group approach in a closed unit of a state hospital. At the end of 3 months serum electrolytes, serum osmolality, and urine specific gravity were within normal limits since the start of the program. Anxiety, as evidenced by restlessness, pacing, increased talking, demanding behavior, hyperactivity, yelling, and irritability, had lessened. This improvement was accompanied by a stabilization of psychotic behavior. The use of restraints dropped from 1303 hr in the 3 months before the program to 20 hr and 55 min for the nine patients in the first 3 months of the program. Progress in relation to the study hypothesis will be evaluated every 3 months.

Schizophrenia and fatal self-induced water intoxication with appropriately-diluted urine.

A 31-year-old woman with untreated chronic schizophrenia developed extreme polydipsia which rapidly led to coma and death due to cerebral edema. Hyponatremia (120 mEq/liter) and serum hypo-osmolality (260 mOsm/kg) were associated with marked polyuria (up to 1850 ml/hour) and appropriately low urinary osmolality (90 mOsm/kg) which responded to treatment. This case and few qualifying previous reports which are reviewed support the possibility that pure self-induced water intoxication with no major contribution of inadequate release of antidiuretic hormone may occur, and that extreme polydipsia can sometimes overwhelm normal renal diluting capacity in psychotic patients.

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

Parameters of water metabolism were measured serially in nine patients with the syndrome of self-induced water intoxication and psychosis (SIWIP). Clinical and laboratory findings indicated that SIWIP patients are type A of the syndrome of inappropriate antidiuresis. Estimated 24-hour urinary excretion of creatinine and early morning urinary creatinine concentration measurements were used to calculate 24-hour urine volumes. Polyuria was considered present for male patients when excretion was estimated to be greater than 2,600 ml of urine/24 hours or early morning urinary specific gravity was less than or equal to 1.003. Male patients with a specific gravity of less than or equal to 1.003 predictably excreted 28,000 ml of urine/day. Severe hyposthenuria may be a biological marker for a population at risk to develop complications of SIWIP, including seizures, coma, and death.

Water intoxication in a psychotic patient with normal renal water excretion.

A psychotic patient with hyponatremia and obtundation following short-term ingestion of large amounts of water was found to have maximally dilute urine, and underwent brisk diuresis until the serum osmolality returned to normal. This is the first report of normal renal diluting capacity as documented by measurement of urine osmolality in a water-intoxicated, schizophrenic patient, and demonstrates that normal renal diluting mechanisms may on occasion be overwhelmed by massive water ingestion.

Hyposthenuria as a marker for self-induced water intoxication and schizophrenic disorders.

Four patients with the syndrome of self-induced water intoxication and schizophrenic disorders, as well as inappropriate antidiuresis, are described. In each case, severe hyposthenuria preceded the clinical symptoms by 1 to 7 years. Hyposthenuria may be a marker for this syndrome.

Evaluation of patients with self-induced water intoxication and schizophrenic disorders (SIWIS).

The complications of water intoxication are well documented in the medical literature. Less well appreciated is the frequent appearance of self-induced water intoxication in patients with schizophrenic disorders. Six such patients are described and compared with the findings in the literature. Nonedematous, nonhypovolemic hyponatremia is the invariable biochemical abnormality in this syndrome and its multiple causes are discussed, including the syndrome of inappropriate antidiuresis. Severe hyposthenuria (urinary specific gravity 1.003 or less) is the silent biological marker that always antedates the complications of self-induced water intoxication and schizophrenic disorders (SIWIS). While recognizing that all patients with polydipsia do not go on to develop water intoxication, this biological marker provides the means to detect patients who may be destined to develop SIWIS; early recognition may prevent the major complications of this syndrome.

Water intoxication secondary to feeding mismanagement. A preventable form of familial seizure disorder in infants.

Water intoxication with seizures secondary to excessive fluid ingestion occurred in four apparently healthy infants in two families; we also review five previously reported cases.

The effect of water diuresis on electrolyte excretion in unanaesthetized dogs.

1. The relation between water loading and electrolyte excretion in dogs fed on a meat diet proved impossible to evaluate owing to the large variability in electrolyte excretion rates in control experiments.2. In animals fed a synthetic diet of constant and known composition the administration of a water load of 2.5% of body weight caused significant increases in the rate of excretion of sodium (P < 0.01) and potassium (P < 0.05). The chloride excretion rate also increased in the one animal tested.3. The significance of these results is discussed.