The syndrome of inappropriate antidiuretic hormone secretion in the elderly.
OBJECTIVE
To determine clinical characteristics of elderly patients presenting with the syndrome of inappropriate antidiuretic hormone secretion (SIADH), their outcome, and the extent of evaluation that is warranted.


METHODS
A retrospective study.


METHODS
An 800-bed primary and tertiary care center in Jerusalem, Israel.


METHODS
Fifty elderly patients, hospitalized with serum sodium levels below 130 mmol/L consistent with a diagnosis of SIADH.


METHODS
Data collection of the medical history, functional status, physical examination, laboratory evaluation, length of hospital stay, treatment, and outcome.


RESULTS
The neurological clinical presentation on admission ranged widely: 48% were fully alert, 42% were stuporotic, and 10% had seizures. Sensorial impairment was significantly associated only with sodium values of less than 110 mmol/L. The majority of patients underwent a comprehensive work-up including chest x-ray, computerized tomography (CT) scans, and thyroid and adrenal function tests. The cause of SIADH in most of the patients remained obscure (60% of cases were idiopathic). The 2 main causes identified were pneumonia in 9 cases (18%) and medication in 6 cases (12%). Most of the patients survived the event; only two patients died, both because of sepsis and not due to hyponatremia. The average hospital stay was 12.8 +/- 9 days.


CONCLUSIONS
Elderly patients with SIADH usually have an idiopathic form of this condition and a benign course. Extensive routine diagnostic procedures are not warranted. Simple measures like medical history taking with special emphasis on medications, physical examination, and chest x-rays can lead to a treatable diagnosis in most patients who do not have the idiopathic form of SIADH.
Hirshberg
B
B
Division of Medicine, Hadassah University Hospital, Hebrew University-Hadassah Medical School, Jerusalem, Israel.
Ben-Yehuda
A
A
D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007177:Inappropriate ADH Syndrome / Q000175:diagnosis* / Q000378:metabolism; D008297:Male; D012189:Retrospective Studies