European Journal of Cardiovascular Medicine

Background: The most frequent electrolyte imbalance seen in clinical practise is hyponatremia, which is characterised by a serum sodium concentration ([Na+]) 135 mEq/L. Mild hyponatremia—serum [Na+] 130–135 mEq/L—occurs in up to 30% of hospitalised patients. [1,2] Acute severe hyponatremia is known to produce cerebral oedema, which can have serious neurological effects. If it is not properly detected and treated, it can be fatal. [3]

Objectives:

1. To study the incidence of hyponatremia in hospitalized adult patients in medical wards.

2. To determine the etiology of clinically significant hyponatremia in 100 patients in medical wards.

3. To determine the clinical presentation of hyponatremia in these patients.

Material & Methods: Study Design:  Hospital based prospective observational study. Study area: Bapuji Hospital & Chigateri Hospital. Study Period: April 2022 to March 2023. Study population:  Patients admitted in  Hospital medical wards with serum sodium less than 130 mmol/L. Sample size: Study consisted a total of 100 subjects. In the hospital, all the patients, as routine, blood samples were taken and serum electrolytes were done in central biochemistry laboratory. The records were followed up for patients with hyponatremia and values repeated once for confirmation. A standard proforma was used to record to detailed history of present complaints, past history including diabetes mellitus, systemic hypertension, Ischemic heart disease, dyslipidemia, neurological, chronic kidney disease / renal disease, regulatory and endocrine problems. A detailed drug history was also recorded.

Results: 67 patients had some neurological symptoms of hyponatremia due to cerebral edema like nausea, vomiting, giddiness and altered sensorium. 14 patients presented with seizures. The lower the sodium value, the higher the incidence of symptomatic hyponatremia. The incidence of symptomatic hyponatremia is more with lowering sodium levels which is statistically significant. All patients with severe hyponatremia had symptoms.

Conclusion: Symptomatic hyponatremia is common among the hospitalized patients. Neurological symptoms are common in hyponatremia patients. SIADH and euvolemic hyponatremia formed the largest subgroup in the study. Drugs, especially diuretics, are a common cause of hyponatremia. A relatively large number of patients had endocrine abnormalities (thyroid, adrenal and pituitary). The mortality was about 10%. It was mainly due to underlying primary diseases. Older age groups had more incidence of hyponatremia. Symptoms of hyponatremia increased with severity of hyponatremia.