POLYDIPSIA AND WATER-INTOXICATION IN PSYCHIATRIC-PATIENTS - A REVIEW OF THE EPIDEMIOLOGIC LITERATURE

Polydipsia among chronic psychiatric patients is poorly understood and underdiagnosed. it may have three stages: simple polydipsia, polydips ia with water intoxication, and physical complications. Epidemiologica l surveys have used staff reports and polyuria measures to identify po lydipsic patients. Water intoxication has been screened by chart revie w, weight, or serum sodium data. According to these surveys, polydipsi a, not explained by medically induced polyuria, may be present in more than 20% of chronic inpatients. Up to 5% of chronic inpatients had ep isodes of water intoxication although mild cases may have been missed. Single time point surveys show that 29% of polydipsic patients had pr esented water intoxication. Methodologically limited clinical studies suggest that polydipsia with water intoxication rather than simple pol ydipsia may be associated with poor prognosis in schizophrenia. Epidem iological surveys found polydipsia with water intoxication to be assoc iated with chronicity, schizophrenia, smoking, some medications, male gender, and white race. New pathophysiological models need to elucidat e these findings.