title: 25-Hydroxyvitamin D, cholesterol, and ultraviolet irradiation.
abstract: Vitamin D deficiency may have implications for cardiovascular health. The purpose of this study was to determine the relationship of 25-hydroxyvitamin D (25[OH]D) to cholesterol and lipoprotein particles and to determine whether increasing 25(OH)D through ultraviolet (UV) irradiation impacted on these parameters in healthy young men and women. This was a randomized trial of 51 adults exposed to suberythemal doses of whole-body irradiation using UV lamps that emitted UV-A and UV-B radiation, compared with a control group, twice weekly for 12 weeks. 25-Hydroxyvitamin D, cholesterol, and lipoprotein subfractions were measured at baseline and after 12 weeks. There was a significant (P < .03) positive association between 25(OH)D and apolipoprotein A-I (Apo A-I) and lipoprotein A-I (Lp A-I). The ratio of low-density lipoprotein to high-density lipoprotein was significantly (P < or = .044) negatively correlated with 25(OH)D levels. The levels of 25(OH)D increased significantly in the treated compared with control group (P < .05). Overall, there were no significant differences between the treated and control groups in any lipoproteins or apolipoproteins after administration of UV irradiation. Subgroup analysis for Apo A-II confined to those with 25(OH)D insufficiency (25[OH]D <75 nmol/L [30 ng/mL]) revealed decreases in Apo A-II in the treated group and increases in the control group that were statistically significantly different between the groups (P = .026). We found a significant positive correlation between 25(OH)D and Apo A-I and Lp A-I and a significant negative correlation between 25(OH)D and the ratio of low-density lipoprotein to high-density lipoprotein. In those with vitamin D insufficiency, we found small decreases in Apo A-II in the treated relative to the control group. Overall, though, twice weekly exposure to UV radiation resulting in an increase in serum 25(OH)D had no significant impact on lipoprotein composition.
authors.affiliation: Department of Veterans Affairs Medical Center, Memphis, TN 38104, USA. lcarbone@utmem.edu
authors.forename: Laura D
authors.initials: LD
authors.lastname: Carbone
authors.forename: E William
authors.initials: EW
authors.lastname: Rosenberg
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Tolley
authors.forename: Michael F
authors.initials: MF
authors.lastname: Holick
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Hughes
authors.forename: Mitchell A
authors.initials: MA
authors.lastname: Watsky
authors.forename: Karen D
authors.initials: KD
authors.lastname: Barrow
authors.forename: Tai C
authors.initials: TC
authors.lastname: Chen
authors.forename: Nathaniel K
authors.initials: NK
authors.lastname: Wilkin
authors.forename: Syamal K
authors.initials: SK
authors.lastname: Bhattacharya
authors.forename: John C
authors.initials: JC
authors.lastname: Dowdy
authors.forename: Robert M
authors.initials: RM
authors.lastname: Sayre
authors.forename: Karl T
authors.initials: KT
authors.lastname: Weber
mesh_terms: D000328:Adult; D016632:Apolipoprotein A-I / Q000097:blood; D002784:Cholesterol / Q000097:blood*; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D005260:Female; D006801:Humans; D017270:Lipoprotein(a) / Q000097:blood; D008297:Male; D014466:Ultraviolet Rays; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D016632:Apolipoprotein A-I; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D017270:Lipoprotein(a); D014807:Vitamin D; C078260:lipoprotein A-I; D002784:Cholesterol; C104450:25-hydroxyvitamin D