MRI changes during water loading in patients with polydipsia and intermittent hyponatremia.

OBJECTIVE: Patients with polydipsia and intermittent hyponatremia have greater ventricle-brain ratios (VBRs) than matched patients without polydipsia and intermittent hyponatremia and normal subjects. Unlike previous studies, this study controlled for the impact of water loading when examining the volume of intracranial structures. METHOD: Under controlled conditions, eight male schizophrenic patients with polydipsia and intermittent hyponatremia were first assigned to either normal fluid intake or oral water loading and then the alternative condition the following day. Magnetic resonance imaging (MRI) volumetric measurements were made with the use of a standardized protocol. RESULTS: During water loading, total VBR and lateral ventricle volume significantly decreased by 13.1% and 12.6%, respectively. A strong association between change in serum sodium concentration and change in VBR was noted across conditions. CONCLUSIONS: These findings indicate that 1) water loading does not account for the diminished brain volume observed in patients with polydipsia and intermittent hyponatremia in previous studies, and 2) hyponatremia can significantly alter brain morphology on MRI.

Polydipsia-hyponatraemia syndrome : epidemiology, clinical features and treatment.

The polydipsia-hyponatraemia syndrome (PHS) occurs in about 5 to 10% of institutionalised, chronically psychotic patients, 80% of whom have schizophrenia. Major clinical features are polydipsia and dilutional hyponatraemia. Complications of PHS include delirium, generalised seizures, coma and death.Nonpharmacological interventions are fluid restriction, diurnal bodyweight monitoring, behavioural approaches, and supplemental oral sodium chloride administration. These interventions require an experienced and dedicated multidisciplinary staff.A number of pharmacological treatments have been assessed for PHS including the combination of lithium and phenytoin, demeclocycline, propranolol, ACE inhibitors, selective serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitors, typical antipsychotic drugs, clozapine and risperidone. Of these agents, the most promising are the combination of lithium and phenytoin, and clozapine.Integrated treatment requires a highly informed multidisciplinary staff, meticulous monitoring of diurnal weight gain and serum sodium level, and careful record keeping. Acute interventions of observation by trained staff, fluid restriction, water-free areas and supplemental sodium chloride administration are based on diurnal weight gain employing a monthly weight chart and a base weight method. Intravenous hypertonic saline is used briefly and administered in a highly controlled manner when patients with PHS present with generalised seizures and coma. Long term strategies include behavioural interventions and the combination of lithium and phenytoin, and clozapine.

Clozapine treatment in polydipsia and intermittent hyponatremia.

BACKGROUND: Recent case reports indicate that clozapine treatment diminishes excessive diurnal weight gain and alleviates hyponatremia observed in some chronically psychotic patients. We examined the influence of clozapine on sodium metabolism and water regulation across a group of patients with the syndrome of polydipsia and intermittent hyponatremia. METHOD: Eleven patients with treatment-resistant DSM-III-R schizophrenia or schizoaffective disorder were studied. Each had a history of repeated diurnal weight gains of greater than 10% with at least one documented bout of hyponatremia in the 6 months before clozapine treatment. We utilized a target weight protocol and serial laboratory measures to compare changes in sodium metabolism and water regulation during 26 weeks of standard antipsychotic medication and 26 weeks of clozapine treatment. RESULTS: Across patients, we found significant improvement in routinely monitored 6 a.m. and 4 p.m. serum sodium, reflecting normalization of sodium metabolism. We also found that the frequency (as reflected by diurnal weight gain), severity (lowest serum sodium), and estimated quantity (calculated urine volume) of polydipsia improved across patients. Improvement in polydipsia and hyponatremia was associated with decreased necessity for monitoring and restrictive interventions, and tended to be associated with psychiatric improvement. CONCLUSION: We found a corrective and stabilizing effect of clozapine on polydipsia and intermittent hyponatremia. Future studies need to examine the relationship of psychiatric improvement and alterations in the regulation of sodium and water physiology to our findings.

Differential effects of neuroleptic and clozapine on polydipsia and intermittent hyponatremia.

Recent reports indicate that clozapine may dramatically decrease both polydipsia and intermittent hyponatremia associated with chronic psychosis. In contrast, there are conflicting reports regarding the impact of standard neuroleptic treatment in this syndrome. We review the relevant literature examining the effects of antipsychotics on the excessive thirst drive and inordinate arginine vasopressin activity observed in patients with water intoxication. Confounding interpretation of the current literature are inconsistent use of diagnostic criteria and treatment outcome measures. If results of preliminary trials is substantiated, clozapine treatment may provide an opportunity to correct methodological problems and provide greater insight into the syndrome of polydipsia and intermittent hyponatremia.

Multidisciplinary approach to psychosis, intermittent hyponatremia, and polydipsia.

The syndrome of psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome), seen in the seriously mentally ill, can result in severe biopsychosocial impairment, including an excessive death rate if not identified early. Because of its impact on the health, functioning, and quality of life of the seriously mentally ill patient, all mental health care providers must be aware of the signs and symptoms of PIP syndrome. Physiological, psychological, behavioral, self-care, and social factors all play a role in the manifestation of the syndrome; it follows that a multidisciplinary approach is crucial to ensure early detection, monitoring, and treatment of this problem both in the hospital and in the community. This article explains how we have incorporated the strengths of various disciplinary strategies into a unified treatment model for managing PIP syndrome and its sequelae.

Neuropsychological manifestations of hyponatremia in chronic schizophrenic patients with the syndrome of psychosis, intermittent hyponatremia and polydipsia (PIP).

We examined the neuropsychological sequelae of water intoxication in nine schizophrenic patients with the syndrome of psychosis, intermittent hyponatremia and polydipsia (PIP). Patients were assessed using a standardized test battery on two occasions following laboratory blood work: once during hyponatremia (serum sodium < 130 mmol/l) and once during normonatremia (serum sodium > 136 mmol/l). Results revealed significant deficits during hyponatremia involving complex information processing skills such as mental flexibility and verbal fluency. In contrast, short-term memory was intact and no deficits in sustained attention or visual-motor scanning were observed. Our results underscore the dramatic fluctuations in neuropsychological functioning due to metabolic and osmotic changes during water loading in PIP syndrome patients. In addition, we found that the neuropsychological effects of hyponatremia are remarkably consistent across patients. These complications, if not recognized, are likely to contribute to worsening of psychosis despite appropriate pharmacological treatment while severely limiting patient ability to actively participate in behavioral interventions.

Case report: recurrent pseudocyesis in a male patient with psychosis, intermittent hyponatremia, and polydipsia.

This report describes a case of recurrent pseudocyesis in a man with psychosis, intermittent hyponatremia, and polydipsia. The pseudocyesis was documented on three separate occasions coinciding with bouts of acute hyponatremia and rapid weight gain stemming from ingestion of large amounts of water. In contrast, no pseudocyesis was elicited during intervening normonatremic states. Abdominal distention, neuropsychological deterioration, and worsening of psychosis during acute hyponatremia are considered as contributing factors to the pseudocyesis.

Development and validation of a behavioral observation measure for the syndrome of psychosis, intermittent hyponatremia, and polydipsia.

A behavioral observation scale (Virginia Polydipsia Scale; VPS) for monitoring drinking patterns was developed and its reliability tested during 25 hours of tandem ratings among six patients with the syndrome of psychosis, intermittent hyponatremia, and polydipsia (PIPS). These ratings were compared to those collected from a control group of six psychiatric inpatients who were similarly observed for 25 hours. The scale was subsequently used to assess day-long drinking in a single PIPS patient. Results demonstrated that the VPS can be reliably administered by trained raters and that it clearly differentiates the drinking patterns of PIPS patients from controls. In addition, our findings highlight associations among drinking behaviors, psychiatric functioning and low serum sodium concentration. On balance, these results support using observational measures of drinking behaviors in future studies of PIPS patients.