Patterns And Clinical Correlates Of Hyponatraemia Among Medical Admissions In A Tertiary Hospital In North-Western Nigeria

Abstract

Hyponatraemia is the most common electrolyte disorder among hospitalized patients and is associated with adverse clinical outcomes. However, data on its prevalence and clinical characteristics among general medical admissions in Nigeria remain limited. The objective was to determine the prevalence, severity, biochemical patterns, and associated clinical conditions of hyponatraemia among patients admitted into the medical wards of Ahmadu Bello University Teaching Hospital (ABUTH), Zaria. This was a hospital-based cross-sectional study involving 199 adult patients admitted into the medical wards of ABUTH, Zaria. Demographic, clinical, and laboratory data were extracted from medical records. Hyponatraemia was defined as serum sodium concentration <135 mmol/L and classified by severity, serum osmolality, and volume status. Binary logistic regression analysis was used to assess associations between selected variables and hyponatraemia. Statistical significance was set at p<0.05. Hyponatraemia was identified in 12 patients, giving a prevalence of 6.0%. The mean age of the study population was 52.03 ± 17.35 years, with females accounting for 58.8%. Most cases of hyponatraemia were mild (75.0%), while moderate and severe forms accounted for 8.3% and 16.7% respectively. Isotonic hyponatraemia was the most common biochemical subtype (58.3%), and the majority of affected patients were euvolaemic (58.3%). Sepsis (25.0%), tuberculosis (16.7%), and chronic kidney disease (16.7%) were the most frequent diagnoses among hyponatraemic patients. Age ≥65 years, sepsis, and chronic kidney disease were not independently associated with hyponatraemia. In conclusion, Hyponatraemia occurred in a small but clinically relevant proportion of medical admissions at ABUTH, Zaria. It was predominantly mild, euvolaemic, and commonly associated with infectious and chronic systemic illnesses. Routine electrolyte monitoring remains essential for early detection and appropriate management.