Ukrainian Consensus on Diagnosis and Management of Vitamin D Deficiency in Adults.

Vitamin D deficiency (VDD) is a global problem, however, there were no Ukrainian guidelines devoted to its screening, prevention, and treatment, which became the reason for the Consensus creation. This article aimed to present the Consensus of Ukrainian experts devoted to VDD management. Following the creation of the multidisciplinary Consensus group, consent on the formation process, drafting and fine-tuning of key recommendations, and two rounds of voting, 14 final recommendations were successfully voted upon. Despite a recent decrease in VDD prevalence in Ukraine, we recommend raising awareness regarding VDD's importance and improving the strategies for its decline. We recommend screening the serum 25-hydroxyvitamin D (25(OH)D) level in risk groups while maintaining a target concentration of 75-125 nmol/L (30-50 ng/mL). We recommend prophylactic cholecalciferol supplementation (800-2000 IU/d for youthful healthy subjects, and 3000-5000 IU/d for subjects from the risk groups). For a VDD treatment, we recommend a short-term administration of increased doses of cholecalciferol (4000-10,000 IU/d) with 25(OH)D levels monitored after 4-12 weeks of treatment, followed by the use of maintenance doses. Additionally, we recommend assessing serum 25(OH)D levels before antiosteoporotic treatment and providing vitamin D and calcium supplementation throughout the full course of the antiosteoporotic therapy.

VITAMIN D LEVEL AND ITS LINK WITH VISUAL ACUITY AND CONTRAST SENSITIVITY IN PATIENTS WITH AGE-RELATED MACULAR DEGENERATION.

OBJECTIVE: The aim: Determination of vitamin D level and its connection with visual functions in patients with age-related macular degeneration, dry form. PATIENTS AND METHODS: Materials and methods: We analyzed the data of studies (25(OH)D3 levels (nmol/l), LogMAR visual acuity and Logarithmic contrast sensitivity) of 2 groups of women of postmenopausal age: 1 group (58 people - 58 eyes) - patients with age-related macular degeneration (dry form) - study group; 2 group (29 people - 29 eyes) - people without ophthalmic pathology - control group. RESULTS: Results: In the study group, 37 patients (63,8%) had vitamin D deficiency, 21 people (36,2%) had vitamin D insufficiency. In the control group, these figures were 69% and 31%, respectively. These indicators were defined as low (the normal supply of vitamin D is considered to be 100 nmol/l and more). Visual acuity due to ETDRS chart in the study group was 0,22±0,04 (in patients with vitamin D deficiency) and 0,12±0,03 (in patients with vitamin D insuffi¬ciency), in the control group - 0,13±0,04 and 0,05±0,04 respectively. In the control group, the logarithmic values of contrast sensitivity (log CS) were 1,58±0,04 log CS (in patients with vitamin D deficiency) and 1,62±0,02 log CS (in patients with vitamin D insufficiency). For patients from the study group, these figures were reduced to 0,98±0,1 log CS and 1,10±0,06 log CS respectively. CONCLUSION: Conclusions: Patients with age-related macular degeneration, dry form, have low levels of vitamin D, with a predominance of its deficiency. It has been determined that with age-related macular degeneration, functional losses are observed when perceiving objects of low contrast.

Effects of Cholecalciferol on Key Components of Vitamin D-Endo/Para/Autocrine System in Experimental Type 1 Diabetes.

OBJECTIVES: Recent prospective studies have found the associations between type 1 diabetes (T1D) and vitamin D deficiency. We investigated the role of vitamin D in the regulation of 25OHD-1α-hydroxylase (CYP27B1) and VDR expression in different tissues of T1D rats. DESIGN: T1D was induced in male Wistar rats by streptozotocin (55 mg/k b.w.). After 2 weeks of T1D, the animals were treated orally with or without vitamin D3 (cholecalciferol; 100 IU/rat, 30 days). METHODS: Serum 25-hydroxyvitamin D (25OHD) was detected by ELISA. CYP27A1, CYP2R1, CYP27B1, and VDR were assayed by RT-qPCR and Western blotting or visualized by immunofluorescence staining. RESULTS: We demonstrated that T1D led to a decrease in blood 25OHD, which is probably due to the established downregulation of CYP27A1 and CYP2R1 expression. Vitamin D deficiency was accompanied by elevated synthesis of renal CYP27B1 and VDR. Conversely, CYP27B1 and VDR expression decreased in the liver, bone tissue, and bone marrow. Cholecalciferol administration countered the impairments of the vitamin D-endo/para/autocrine system in the kidneys and extrarenal tissues of diabetic rats. CONCLUSIONS: T1D-induced vitamin D deficiency is associated with impairments of renal and extrarenal CYP27B1 and VDR expression. Cholecalciferol can be effective in the amelioration of diabetes-associated abnormalities in the vitamin D-endo/para/autocrine system.