Relationship between hyponatremia and diabetes mellitus
A Duran, M Cuesta, I Runkle, P de Miguel, G Sotres & J Marco
Aims: Our aim is to retrospectively analyze the diagnosis of hyponatremia in the discharge sheets of a tertiary hospital during 5 years and its relationship with type 1 and 2 diabetes mellitus.
Methods: Data from the MBDS (Minimum Basic Data Set) of the discharged patients from the Hospital Clínico San Carlos (Madrid) between the years 2005 to 2009 was analysed. The 5th Edition of the ICD-9-CM was used for the codification of the diagnoses and procedures. The system of patient classification of Diagnosis Related Groups AP-DRG (version 21.0) was used for the grouping of discharge processes. The Charlson index was use as a measure of comorbidity. Patients with a main or secondary diagnosis of hyponatremia suffering also from type 1 or type 2 diabetes were selected and analyzed. Age, sex, length of stay, comorbidity, procedures and mortality were taken into account.
Results: Reported hyponatremia was 1.7% in type 1 diabetes and 2.3% in type 2. Mean age was 33.6 years for type 1 and 68.3 years for type 2. In type 1 diabetes, 48.7% were males vs 43.1% in type 2 diabetes. Mean stay was 7.2 days for type 1 vs 9.9 days for type 2. A Charlson index >2 was present in 17% of type 1 diabetic patients and in 22% of those with type 2. Mortality reached 14% in type 1 and 7% in type 2.
Discussion: The low prevalence of the notification of hyponatremia, very far from the real prevalence of this disturbance is our first observation. In our series, two populations are distinguished: patients with type 1 diabetes are younger, with a shorter stay, less comorbidity and higher mortality. On the other side, type diabetics are older, predominantly female, with higher comorbidity and longer hospitalizations but lower mortality.
Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.
Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.