National survey of doctors on hypo-and hypernatremia in the context of real clinical practice

BACKGROUND: The prevalence of dysnatremia varies widely (from 1 to 63%), and depends on comorbidities, the effects of more than 18 hormones and hormone-like substances, which confirms the importance of maintaining blood sodium levels in the tight physiologic range and makes it possible to consider its deviations as an endocrine pathology. Both hypo- and hypernatraemia are associated with a multiple increase in mortality, risk of fractures, and gross balance disturbances. At the same time, the clinical manifestations of dysnatremia are not specific, reflect an osmotically mediated decrease in brain function, which potentially may be missed in clinical practice.

AIMS: to study the specifics of diagnosis, differential diagnosis and treatment of dysnatremia states by specialist doctors using a sociological survey method.

MATERIALS AND METHODS: A cross-sectional sociological uncontrolled study was conducted by questioning doctors about hypo- and hypernatremia using the online questionnaire “Questionnaire on hypo-and hypernatremia in clinical practice” created on the Google forms platform. The invitation to fill in the questionnaire was sent to the email addresses included in the database of the Russian Association of Endocrinologists. A total of 353 completed questionnaires were received.

RESULTS: The poll demonstrated a low frequency of determining blood sodium levels - less than 38% of specialists prescribe sodium in more than half of the cases, including the cases of diseases associated with dysnatremia, which correlates with less practical experience of doctors. The overwhelming majority of endocrinologists (82%) in their clinical practice encounters deviations of the sodium levels in patients, but only 6% recognize the possession of the competence of managing patients with dysnatremia. The discrepancy between the lower limit of normal range to 135-136 mmol/l was observed in 22% (62/278), the inconsistency of the upper normal limit to 145-146 mmol/l - in 47% (131/278) of laboratories, and in 33% (41/278) laboratories, which are used by doctors, there was a discrepancy along both limits of the reference interval. The presence of a hypertonic solution (3%) of sodium chloride in a hospital was noted only by 38% of respondents.

Conclusions: There is an unphysiological variation in reference intervals for blood sodium concentration in 55% of laboratories, a low frequency of sodium levels evaluation in the blood (in more than half of clinical situations only 38.2% of doctors prescribe the estimation of blood sodium level) and the lack of educational competence in managing patients with syndromes of hypo- and hypernatremia in 94% of endocrinologists.

sodium, hyponatremia, hypernatremia, dysnatremia, central diabetes insipidus, syndrome of inadequate secretion of antidiuretic hormone, sociological survey, endocrinologist

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