Risk factors for symptomatic hyponatraemia: the role of pre‐existing asymptomatic hyponatraemia

Internal Medicine Journal - Tập 37 Số 3 - Trang 149-155 - 2007
Melisha Bissram1, Fraser Scott1, Lei Liu1, Mitchell H. Rosner1
11 Department of Internal Medicine, Division of Nephrology and 2Department of Health, Evaluation Sciences, University of Virginia Health System, Charlottesville, Virginia, USA

Tóm tắt

AbstractBackground: Hyponatraemia is associated with substantial morbidity and mortality. Identification of the risk factors associated with the development of symptomatic hyponatraemia is important in determining preventive strategies.Methods: A retrospective analysis of the risks factors associated with the development of severe, symptomatic hyponatraemia requiring hospital admission over the past 3 years at our institution was carried out.Results: Forty‐seven patients (26 women, 21 men) with a hospital admission serum sodium <134 mmol/L were identified. Of these patients, 31 (65.9%) had associated changes in the mental status that improved with the treatment of the hyponatraemia suggesting causality. The average admission sodium level of this cohort was 118.8 mmol/L. Symptomatic hyponatraemia was associated with volume depletion (32.6%), congestive heart failure (26%), syndrome of inappropriate antidiuretic hormone (26%), thiazide diuretic use (26%) and selective serotonin re‐uptake inhibitor use (26%). In 21.7% of cases, the cause was multifactorial (congestive heart failure, syndrome of inappropriate antidiuretic hormone or medication use with volume depletion). In 11% of cases, patients were taking both thiazide diuretics and serotonin re‐uptake inhibitors. Most importantly, 70.9% of all patients admitted with symptomatic hyponatraemia had pre‐existing hyponatraemia that was untreated and believed to be asymptomatic (P < 0.05). This was the most common risk factor identified. We next investigated the prevalence of presumed asymptomatic hyponatraemia in the outpatient setting. Out of 27 496 patients analysed, 14% had serum sodium levels less than or equal to 134 mEq/L and 4% had values less than 130 mEq/L.Conclusion: Pre‐existing asymptomatic hyponatraemia is a common finding and is associated with a high risk for the development of worsening hyponatraemia with altered mental status.

Từ khóa


Tài liệu tham khảo

10.1177/000456329903600204

10.1056/NEJM200005253422107

10.1345/aph.1D105

10.1111/j.1532-5415.1996.tb06410.x

10.1111/j.1532-5415.1995.tb06623.x

10.1046/j.1532-5415.2001.49157.x

Misra SC, 1989, Hyponatremia in elderly hospital in‐patients, Br J Clin Pract, 43, 295, 10.1111/j.1742-1241.1989.tb08751.x

10.1111/j.1532-5415.1979.tb06439.x

10.1093/ageing/12.1.77

10.1016/0920-9964(93)90047-M

Ellis SJ, 1995, Severe hyponatremia: complications and treatment, QJM, 85, 905

10.1038/ki.1976.82

1998, Hyponatremia: age‐related risk factors and therapy decisions, Geriatrics, 53, 32

10.1016/S0889-8529(18)30192-0

10.1681/ASN.V781106

10.1111/j.1532-5415.1989.tb02244.x

10.1345/aph.19140

10.1002/gps.591

10.1016/0002-9343(81)90822-6

Clark BA, 1994, Increased susceptibility to thiazide‐induced hyponatremia in the elderly, J Am Soc Nephrol, 5, 1106, 10.1681/ASN.V541106

10.7326/0003-4819-102-2-164

10.1097/00000441-200402000-00012

Rose BD, 2001, Clinical Physiology of Acid‐Base and Electrolyte Disorders