Clinical characteristics and outcomes of hyponatraemia associated with oral water intake in adults: a systematic review

Abstract

IntroductionExcessive water intake is rarely associated with life-threatening hyponatraemia. The aim of this study was to determine the clinical characteristics and outcomes of hyponatraemia associated with excess water intake.MethodsThis review was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. All studies (case reports, observational or interventional studies) reporting excess water intake and hyponatraemia in adults (1946–2019) were included.ResultsA total of 2970 articles were identified and 177 were included (88.7% case reports), consisting of 590 patients. The mean age was 46±16 years (95% CI 44 to 48 years), 47% female, 52% had a chronic psychiatric disorder and 31% had no underlying condition. The median volume of water consumed and serum sodium at presentation was 8 L/day (95% CI 8.9 to 12.2 L/day) and 118 mmol/L (95% CI 116 to 118 mmol/L), respectively. The motivator for increased water consumption was psychogenic polydipsia (55%); iatrogenic (13%); exercise (12%); habitual/dipsogenic polydipsia (7%) and other reasons (13%). The clinical features on presentation were severe in 53% (seizures, coma); moderate in 35% (confusion, vomiting, agitation) and mild in 5% (dizziness, lethargy, cognitive deficit) and not reported in 5% of studies. Treatment was supportive in 41% of studies (fluid restriction, treatment of the underlying cause, emergency care), and isotonic and hypertonic saline was used in 18% and 28% of cases, respectively. Treatment-related complications included osmotic demyelination (3%) and rhabdomyolysis (7%), and death occurred in 13% of cases.ConclusionWater intoxication is associated with significant morbidity and mortality and requires daily intake to substantially exceed population-based recommendations. The limitations of this analysis are the low quality and high risk of bias of the included studies.PROSPERO registration numberA pre-existing protocol in the international prospective register of systematic reviews was updated to incorporate any new amendments and reregistered at http://www.crd.york.ac.uk/PROSPERO (registration no. CRD42019129809).

Observational Study of the Association between Hyponatremia and Rhabdomyolysis in Patients Presenting to Hospital

“…Profiling of patients with hyponatremia indicated that patients with psychotic disorders, the use of psychotropic (antipsychotic or antidepressant) medications, and excessive alcohol intake were over-represented. This finding is consistent with a systematic review of hyponatremia and excessive water intake, which noted that 52% of patients had schizophrenia-spectrum disorders and 42% were on psychotropic medications associated with hyponatremia [ 18 ].…”

High Urinary Sodium Concentrations in Severe SIADH: Case Reports of 2 Patients and Literature Review

“…It is likely that the water intake of 2–3L/day caused further dilutional hyponatremia in the setting of marked ADH activation, as reflected by the high urine osmolality and urine sodium concentration. While the fall in serum osmolality would have usually suppressed thirst, the patient continued to drink as self-remedy for his abdominal symptoms, thus resulting in a vicious cycle of worsening hyponatremia ( 34 ).…”

Severe hyponatremia due to water intoxication in a child with sickle cell disease: A case report

“…In adults, several cases of voluntary water intoxication have been reported in schizophrenic and anorectic patients. 2 Other papers describe symptomatic hyponatremia due to water intoxication in marathon runners; 3 iatrogenic polydipsia because of misinterpretation of medical advice has been also described. 2,4 Some cases of voluntary overconsumption of water occurred as consequence of water-drinking games, 5 but only one was reported in a child.…”

“…2 Other papers describe symptomatic hyponatremia due to water intoxication in marathon runners; 3 iatrogenic polydipsia because of misinterpretation of medical advice has been also described. 2,4 Some cases of voluntary overconsumption of water occurred as consequence of water-drinking games, 5 but only one was reported in a child. 6 In childhood, water intoxication affects more frequently infants and toddlers.…”

“…15,16 On the contrary, the management of hyponatremia relies on cautious hydration with isotonic fluids (0.9% saline solution), free water restrictions, diuretics, or a combination of them. 1,2 The goal is slow and cautious correction of [Na+], in order to avoid complications such as pontine myelinolysis. Faster correction with hypertonic 3% saline solution is reserved to patients with status epilepticus or with severe neurological symptoms due to hyponatremia.…”