Retrospective Cohort Study Of Hyponatremic Patients In Internal Medicine

Hyponatremia is the most common electrolyte abnormality in clinical medicine.Because of different etiologies, non-specific clinical manifestations, and often beingcovered by primary disease, it is easy to cause misdiagnosis. Severe acutehyponatremia has high fatality rate, chronic hyponatremia is associated with mortalityand longer hospital stays. If the treatment of hyponatremia is inappropriate orexcessive, it may result in increased mortality associated with abnormal nervoussystem. Therefore, systemic analysis of pathogenesis and clinical characteristics ininternal medicine patients with hyponatremia, has an important significance forguiding the clinical decision-making. Thus, in order to further improve the cure rateand survival rate in patients who have hyponatramia, We medical workers should paymore attention to it.Objective：As a familiar electrolyte disorder in clinic, it has been confirmed thathyponatremia can affect curative effect and increased mortality. This research mainlyobserved the reason of disease, the situation of first symptom and prognosis, anddiscussed the pathogenesis of hyponatremia, there by guiding the clinical preventionand treatment of the disease.Materials and methods: A retrospective hospital record study, which enrolled692patients with hyponatremia, was performed at the internal medicine department ofthe Bethune First Hospital of Jilin University from November2011to April2012.Allpatients were divided into mild, moderate and severe group according to preliminarysurvey of blood sodium levels.We ask for details and record the history of theinductees, including sex, age, length of stay, initial symptoms, causes andbiochemical indicators, such as serum sodium, potassium, chlorine, calcium, ureanitrogen, creatinine, albumin, and blood sugar. Correcting blood sodium level forthose who were diagnosed as hyperlipidemia and diabetes, diabetic ketosis anddiabetic ketoacidosis definitely, so that we could estimate whether the patients hadtrue hyponatremia or not. For each group analyse risk factors, clinical characteristicsand outcomes of these patients. Statistical method: Use SPSS17.0statistics software for data analysis.Results：(1)There is a total number of20534people who were hospitalized in thedepartment of internal medicine system, among whom692cases were diagnosed ashyponatremia, the morbidity was3.37%. The number of mild hyponatremia was morethan half (67.34%), followed by moderate hyponatremia (26.01%), severehyponatremia was fewer than both of the above(6.65%).(2)The average valueincreased gradually of patients’ length of stay in each group, but the difference wasnot statistically significant (P>0.05). Patients with hyponatremia were likely tocombine with other electrolyte disturbances, such as hypochloraemia andhypocalcemia, especially in patients with moderate or severe hyponatremia (P<0.05).(3) The top ten pathogenic factors of all patients reseached in this study: the mostcommon cause was pneumonia (1.6%), the rest followed by other causes leading tohyponatremia (10.55), aute exacerbation of chronic obstructive pulmonary disease(8.96%), hepatocirrhosis (6.07%), loss of gastrointestinal digestive juice and digestivesystem tumors (5.64%), heart failure (5.20%), inadequate intake (4.62%), chronicbronchitis (3.76%), hemorrhage (3.47%).(4)Patients with low serum osmotality werethe most common (84.68%). Pneumonia was the most common cause in mild andmoderate hyponatremia. Inadequate intake of sodium and liver cirrhosis were themajor causes of severe hyponatremia.(5)Over half of the patients with low serumosmolality were euvolemic hypotonic hyponatremia (59.00%), followed byhypovolemic hypernatremia (21.00%), hypervolemic hyponatremia had a lowestpercentage of20.00%. Euvolemic hypernatremia was caused most frequently bySIADH. Loss of gastrointestinal digestive juice was the dominant reason ofhypovolemic hyponatremia, and in hypervolemic hyponatremia, hepatocirrhosis waseasily to be seen.(6)In this study, the reseach objects’ expression of primary diseasesymptoms as the first symptom appeared to have the highest proportion (40.75%).Gastrointestinal symptom come next (36.71%).(7)Pulmonary diseases accounted forthe highest percentage of all336cases with SIADH. Tumors were the second mostcommon cause of SIADH, and then central nervous system diseases.(8)The mortalityof moderate and severe hyponatremia were obviously greater than mild of thehospitalized patients in internal medicine.(9)Of all692cases, there were29patientsconsidered as hyponatremia associated with endocrine and metabolic diseases exceptfor SIADH, among which hyperglycemia was the most common. Conclusions：(1)Hypotonic hyponatremia is the major cause of hyponatremia ininternal medicine;(2)Other electrolyte disturbances may accompany hyponatremia,particularly when blood sodium is low;(3)In patients with hypotonic hyponatremia,euvolemic hyponatremia is the most common classification, and SIADH is thedominant pathogenic factors;(4)There is a correlation between age and the reductionof serum sodium, and the prognosis in elderly patients with hyponatremia is poor;(5)Clinical manifestations of hyponatremia are lack of specificity, it is usual to see theprimary disease expressions as the first symptom;(6)DKA was the most commonetiology of hyponatremia associated with endocrine diseases;(7)Clinicians should paymore attention to this disorder, and further improve the relevant diagnostic tests.