Abstract
A high prevalence of vitamin D insufficiency has been found in the general population, in patients with chronic kidney disease and in kidney transplant patients. During winter there is a higher prevalence of vitamin D insufficiency due to the lack of solar ultraviolet B (UVB) exposure. Kidney transplant patients are advised to avoid sun exposure because of their high risk of skin cancer. This is considered to be one of the main reasons for the very high prevalence of vitamin D insufficiency in these patients. Whether circannual rhythm of vitamin D is totally reversed in kidney transplant patients is not known. In this single centre prospective observational study, 50 kidney transplant patients visiting our outpatient clinic in January and February 2011 were included. Serum concentration of 25-hydroxvitamin D (25[OH]D), 1-25-hydroxvitamin D (1-25[OH]D) and intact parathormone (iPTH) were measured at study entry and 6 months later in summer. A total of 90% (45/50) of the study population had vitamin D deficiency 25(OH)D (<50 nmol/l) during winter. There was a rise of 25(OH)D in 94% (47/50) of patients from winter to summer (p <0.0001) leading to a decline of 25(OH)D deficiency from 90 to 60%, to a rise of 25(OH)D insufficiency from 6 to 26% and normal 25(OH)D from 4 to 14%, respectively (p = 0.0024). Vitamin D insufficiency during winter is very common in kidney transplant patients at our centre. Despite avoidance of exposure to UVB there is a preserved circannual rhythm of vitamin D in kidney transplant patients.
Highlights
Vitamin D is essential for calcium, phosphorus and bone metabolism
A high prevalence of vitamin D insufficiency has been found in the general population, in patients with chronic kidney disease and in kidney transplant patients
During winter there is a higher prevalence of vitamin D insufficiency due to the lack of solar ultraviolet B (UVB) exposure
Summary
Vitamin D is essential for calcium, phosphorus and bone metabolism. In addition there are links between vitamin D deficiency and infectious diseases, cardiovascular diseases and cancer [1]. Vitamin D deficiency is very common in the general population especially during winter with an even higher prevalence in patients with chronic kidney diseases and kidney transplant patients [2–7]. The major source of vitamin D is the cutaneous production by exposure to solar ultraviolet B (UVB). Inadequate exposure to UVB is the major cause of vitamin D deficiency [8]. Factors that influence the cutaneous vitamin D production are time of day, season of the year, latitude, age, skin pigmentation and sunscreen use [8–14]. The high prevalence of vitamin D deficiency in kidney transplant patients is thought to be due the general recommendation of sun protection and sun avoidance in these patients because of their high risk of skin cancer [15]. We measured vitamin D during winter and summer in kidney transplant patients with steroid free immunosuppressive maintenance therapy
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
