title: The effect of narrowband UV-B treatment for psoriasis on vitamin D status during wintertime in Ireland.
abstract: OBJECTIVE
  To determine whether narrowband UV-B (NB-UV-B) may mediate its beneficial effect on psoriasis by increasing vitamin D levels, and to assess the effect of NB-UV-B on vitamin D status in patients with psoriasis in wintertime.
  
  
  METHODS
  A prospective controlled study from October 2008 to February 2009.
  
  
  METHODS
  A dermatology outpatient department at a university teaching hospital.
  
  
  METHODS
  Thirty consecutive patients with psoriasis treated with NB-UV-B and 30 control patients with psoriasis were recruited. Control patients were recruited within 1 week of treated patients to control for seasonal variation of serum 25-hydroxyvitamin D [25(OH)D] levels. One patient with photo aggravated psoriasis was withdrawn from the study.
  
  
  METHODS
  Narrowband UV-B was administered 3 times per week.
  
  
  METHODS
  Serum 25(OH)D was measured at baseline, after 4 weeks and at completion of treatment.
  
  
  RESULTS
  Levels of serum 25(OH)D increased significantly(P< .001) from a median (range) of 23 (9-46)ng/mL at baseline to 51 [rather than 59, as given in the originally published article] (32-112) ng/mL at the end of NB–UV-B treatment compared with no change in the control group [corrected]. The change in serum 25(OH)D level correlated with the number of exposures of NB-UV-B (r = 0.61; P < .001) and cumulative UV-B dose (r = 0.47; P = .01) but not with treatment response. At the end of the study, all patients in the treatment group were vitamin D sufficient, but 75% of the control group had vitamin D insufficiency [serum 25(OH)D level <20 ng/mL]. In a multiple regression model, prior phototherapy was the sole predictor of baseline serum 25(OH)D level (r(2) = 0.13; P = .006), whereas the number of exposures of NB-UV-B predicted change in serum 25(OH)D level (r(2) = 0.38; P = .001).
  
  
  CONCLUSIONS
  Narrowband UV-B effectively increases serum 25(OH)D level while clearing psoriasis. Up to 75% of Irish patients with psoriasis were shown to be vitamin D insufficient during wintertime.
authors: Baylor Research Institute, 3900 Junius Street, Dallas, TX 75246, USA. Caitriona.ryan@baylorhealth.edu
authors: Caitriona
authors: C
authors: Ryan
authors: Benvon
authors: B
authors: Moran
authors: Malachi J
authors: MJ
authors: McKenna
authors: Barbara F
authors: BF
authors: Murray
authors: Jennifer
authors: J
authors: Brady
authors: Paul
authors: P
authors: Collins
authors: Sarah
authors: S
authors: Rogers
authors: Brian
authors: B
authors: Kirby
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006785:Hospitals, University; D006801:Humans; D007494:Ireland / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011565:Psoriasis / Q000532:radiotherapy*; D012044:Regression Analysis; D012621:Seasons; D016896:Treatment Outcome; D014467:Ultraviolet Therapy / Q000379:methods*; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood / Q000528:radiation effects; D014808:Vitamin D Deficiency / Q000453:epidemiology / Q000532:radiotherapy*; D055815:Young Adult
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D