Endocrine Abstracts

Introduction

Clinical guidelines for the prevention and treatment of vitamin D deficiency in adults were formulated and implemented into clinical practice by the Russian association of endocrinologists in 2014. While having multiple health benefits, in some cases, prescribing vitamin D supplements may be accompanied by its toxicity, which has various manifestations and exert potentially dangerous health consequences.

Aim

To study the frequency and key features of vitamin D toxicity in ’real-life’ clinical practice settings.

Materials and methods

710 healthcare professionals took part in an online survey in January 2021. Endocrinologists accounted for 79% of respondents while 21% of survey participants were doctors of other specialties, 94% were women, all age groups from 20 to 65 + years old were presented nearly equally.

Results

16.2% of interviewed doctors had met with a toxicity of vitamin D: once – 42%, twice – 25.2%, three times – 21% and 11.8% reported 4 or more cases over the course of their clinical practice. The most common reasons for toxicity of vitamin D were the intake of an increased doses of colecalciferol initiated by the patient (58.3%) or by the doctor (36%), as well as the intake of active metabolites of vitamin D (24%). Somewhat less often, doctors observed an overdose due to an inaccuracy in the drug concentration indicated by the manufacturer (the actual was higher than stated) – in 22.3%. Least often, doctors met with an overdose due to a genetic defect of CYP24А1 (11.4%), granulomatous (sarcoidosis, histiocytosis, tuberculosis, etc.) (8%) or lymphoproliferative diseases (4.6%). About 70% of doctors always refer for a blood calcium evaluation along with 25(OH)D, 77.2% also check parathyroid hormone levels and 24% – calcium levels in 24 h urine.

Conclusions

Endocrinologists are often faced with an overdose of vitamin D. Particular care should be taken when prescribing high doses of colecalciferol or active metabolites/analogues of vitamin D without regular monitoring of the parameters of calcium-phosphorus metabolism, as well as when patients take them on their own.