Original Research

Narrowband UVB Treatment Increases Serum 25-Hydroxyvitamin D Levels in Patients With Chronic Plaque Psoriasis

Cutis. 2017 June;99(6):431-435

References

Şavk E. Immunology of Photo(chemo)therapy. Turkderm. 2010;44(suppl 2):62-66.
Ferahbaş A. Phototherapy modalities and protocols. Turkderm. 2010;44(suppl 2):67-72.
Ibbotson SH, Bilsland D, Cox NH, et al. An update and guidance on narrowband ultraviolet B phototherapy: a British Photodermatology Group Workshop report. Br J Dermatol. 2004;151:283-297.
Norval M, Björn LO, de Gruijl FR. Is the action spectrum for the UV-induced production of previtamin D₃ in human skin correct? Photochem Photobiol Sci. 2010;9:11-17.
Holick MF. Vitamin D deficiency. N Engl J Med. 2007;357:266-281.
McKenzie RL, Liley JB, Björn LO. UV radiation: balancing risks and benefits. Photochem Photobiol. 2009;85:88-98.
Holick MF. High prevalence of vitamin D inadequacy and implications for health. Mayo Clin Proc. 2006;81:353-373.
May E, Asadullah K, Zügel U. Immunoregulation through 1,25-dihydroxyvitamin D₃ and its analogs. Curr Drug Targets Inflamm Allergy. 2004;3:377-393.
Reichrath J. Vitamin D and the skin: an ancient friend, revisited. Exp Dermatol. 2007;16:618-625.
Fu LW, Vender R. Systemic role for vitamin D in the treatment of psoriasis and metabolic syndrome. Dermatol Res Pract. 2011;2011:276079.
Gisondi P, Rossini M, Di Cesare A, et al. Vitamin D status in patients with chronic plaque psoriasis. Br J Dermatol. 2012;166:505-510.
Orgaz-Molina J, Buendía-Eisman A, Arrabal-Polo MA, et al. Deficiency of serum concentration of 25-hydroxyvitamin D in psoriatic patients: a case-control study. J Am Acad Dermatol. 2012;67:931-938.
Osmancevic A, Landin-Wilhelmsen K, Larkö O, et al. UVB therapy increases 25 (OH) vitamin D syntheses in postmenopausal women with psoriasis. Photodermatol Photoimmunol Photomed. 2007;23:172-178.
Ryan C, Moran B, McKenna MJ, et al. The effect of narrowband UV-B treatment for psoriasis on vitamin D status during wintertime in Ireland. Arch Dermatol. 2010;146:836-842.
Vahavihu K, Ala-Houhala M, Peric M, et al. Narrowband ultraviolet B treatment improves vitamin D balance and alters antimicrobial peptide expression in skin lesions of psoriasis and atopic dermatitis. Br J Dermatol. 2010;163:321-328.
Lesiak A, Narbutt J, Pawlaczyk M, et al. Vitamin D serum level changes in psoriatic patients treated with narrowband ultraviolet B phototherapy are related to the season of the irradiation. Photodermatol Photoimmunol Photomed. 2011;27:304-310.
Osmancevic A, Landin-Wilhelmsen K, Larko O, et al.Vitamin D production in psoriasis patients increases less with narrowband than with broadband ultraviolet B phototherapy. Photodermatol Photoimmunol Photomed. 2009;25:119-123.
Romaní J, Caixàs A, Carrascosa JM, et al. Effect of narrowband ultraviolet B therapy on inflammatory markers and body fat composition in moderate to severe psoriasis. Br J Dermatol. 2012;166:1237-1244.
Diehl JW, Chiu MW. Effects of ambient sunlight and photoprotection on vitamin D status. Dermatol Ther. 2010;23:48-60.
Armas LA, Dowell S, Akhter M, et al. Ultraviolet-B radiation increases serum 25-hydroxyvitamin D levels: the effect of UVB dose and skin color. J Am Acad Dermatol. 2007;57:588-593.
Olds WJ, McKinley AR, Moore MR, et al. In vitro model of vitamin D₃ (cholecalciferol) synthesis by UV radiation: dose-response relationships. J Photochem Photobiol B. 2008;93:88-93.

Comment

The most effective UV wavelength for vitamin D synthesis is 295 to 300 nm, and therefore broadband UVB is frequently studied when determining the relationship between phototherapy and serum vitamin D levels.⁴ The current study demonstrated a statistically significant increase in serum 25(OH)D levels following NB-UVB treatment in patients with moderate to severe chronic plaque psoriasis (P<.001). This result supports other studies reporting that NB-UVB treatment in psoriasis patients increases serum 25(OH)D levels.^13-18

The main factor in the effective UVB level for vitamin D synthesis is the angle at which solar radiation reaches the earth, which is affected by the longitude, latitude, and time of day.¹⁹ For this reason, we planned to perform our study at a single center. Patients who stayed in open areas for more than 2 hours per day during the summer months (May through September) were excluded from the study to decrease the effect of seasonal changes on vitamin D levels. We evaluated the seasonal variation of vitamin D levels and found no relationship between seasonal changes and serum 25(OH)D levels. Therefore, the potential effect of seasonal changes on the vitamin D levels of study participants was excluded from the study.

The response to UV radiation changes according to age and Fitzpatrick skin type because 7-dehydrocholesterol levels decrease with age and melanin prevents the access of UVB photons to 7-dehydrocholesterol.²⁰ The basal serum 25(OH)D levels were deficient in 81.63% of participants and inadequate in 18.37%. In this study, we also observed that the basal serum 25(OH)D levels were significantly lower in patients with Fitzpatrick skin type II than in Fitzpatrick skin type I (P=.039). The mean (SD) serum 25(OH)D level at baseline was 14.14 (6.70) ng/mL and posttreatment was 46.42 (15.51) ng/mL in the 32 patients who completed the study. Serum 25(OH)D levels showed a statistically significant increase after NB-UVB treatment (P<.001). The increased serum 25(OH)D levels after NB-UVB phototherapy were not associated with Fitzpatrick skin type, which was consistent with the results of Osmancevic et al.¹⁷ The adjusted NB-UVB doses according to the different skin types might be responsible for this result in our study.

Participant age did not have a significant effect on serum 25(OH)D levels, similar to other studies in the literature.^13,17 We believe that artificial UVB radiation at high doses can compensate for the 7-dehydrocholesterol that decreases in the skin with aging.

We observed no significant change in the serum calcium and phosphorus levels with NB-UVB treatment in our study. None of the participants had a metabolic disorder related to increased 25(OH)D levels. The serum ALP and PTH levels decreased significantly following treatment (P=.001 and P=.019, respectively), which may have been secondary to increased serum 25(OH)D levels.

Posttreatment serum 25(OH)D levels were compared with the number of NB-UVB phototherapy sessions and maximum dose values. The posttreatment serum 25(OH)D levels were found to be related to the number of sessions received, but this value was not correlated with the maximum dose received. The MED and maximum dose were determined according to the Fitzpatrick skin type of the participants. Therefore, increased serum 25(OH)D levels with an increased number of sessions was an expected result. Our observation is in accordance with the finding described by Ryan et al.¹⁴ On the other hand, an in vitro study conducted by Olds et al²¹ reported that the relationship between UV light and cholecalciferol synthesis was not linear.

We found that increased serum 25(OH)D levels after treatment were not correlated with the decrease in PASI score, similar to studies by Romaní et al¹⁸ and Ryan et al.¹⁴ These results suggest that the clinical improvement following NB-UVB treatment is independent of the increased serum 25(OH)D levels in psoriasis patients.

Conclusion

In conclusion, we found that the serum 25(OH)D levels that increase as a result of NB-UVB therapy for the treatment of chronic plaque psoriasis has no statistically significant relationship with the age, Fitzpatrick skin type, baseline PASI score, changes in PASI, or maximum dose, while a positive relationship is present between the serum 25(OH)D levels and the number of sessions of NB-UVB.

References

Şavk E. Immunology of Photo(chemo)therapy. Turkderm. 2010;44(suppl 2):62-66.
Ferahbaş A. Phototherapy modalities and protocols. Turkderm. 2010;44(suppl 2):67-72.
Ibbotson SH, Bilsland D, Cox NH, et al. An update and guidance on narrowband ultraviolet B phototherapy: a British Photodermatology Group Workshop report. Br J Dermatol. 2004;151:283-297.
Norval M, Björn LO, de Gruijl FR. Is the action spectrum for the UV-induced production of previtamin D₃ in human skin correct? Photochem Photobiol Sci. 2010;9:11-17.
Holick MF. Vitamin D deficiency. N Engl J Med. 2007;357:266-281.
McKenzie RL, Liley JB, Björn LO. UV radiation: balancing risks and benefits. Photochem Photobiol. 2009;85:88-98.
Holick MF. High prevalence of vitamin D inadequacy and implications for health. Mayo Clin Proc. 2006;81:353-373.
May E, Asadullah K, Zügel U. Immunoregulation through 1,25-dihydroxyvitamin D₃ and its analogs. Curr Drug Targets Inflamm Allergy. 2004;3:377-393.
Reichrath J. Vitamin D and the skin: an ancient friend, revisited. Exp Dermatol. 2007;16:618-625.
Fu LW, Vender R. Systemic role for vitamin D in the treatment of psoriasis and metabolic syndrome. Dermatol Res Pract. 2011;2011:276079.
Gisondi P, Rossini M, Di Cesare A, et al. Vitamin D status in patients with chronic plaque psoriasis. Br J Dermatol. 2012;166:505-510.
Orgaz-Molina J, Buendía-Eisman A, Arrabal-Polo MA, et al. Deficiency of serum concentration of 25-hydroxyvitamin D in psoriatic patients: a case-control study. J Am Acad Dermatol. 2012;67:931-938.
Osmancevic A, Landin-Wilhelmsen K, Larkö O, et al. UVB therapy increases 25 (OH) vitamin D syntheses in postmenopausal women with psoriasis. Photodermatol Photoimmunol Photomed. 2007;23:172-178.
Ryan C, Moran B, McKenna MJ, et al. The effect of narrowband UV-B treatment for psoriasis on vitamin D status during wintertime in Ireland. Arch Dermatol. 2010;146:836-842.
Vahavihu K, Ala-Houhala M, Peric M, et al. Narrowband ultraviolet B treatment improves vitamin D balance and alters antimicrobial peptide expression in skin lesions of psoriasis and atopic dermatitis. Br J Dermatol. 2010;163:321-328.
Lesiak A, Narbutt J, Pawlaczyk M, et al. Vitamin D serum level changes in psoriatic patients treated with narrowband ultraviolet B phototherapy are related to the season of the irradiation. Photodermatol Photoimmunol Photomed. 2011;27:304-310.
Osmancevic A, Landin-Wilhelmsen K, Larko O, et al.Vitamin D production in psoriasis patients increases less with narrowband than with broadband ultraviolet B phototherapy. Photodermatol Photoimmunol Photomed. 2009;25:119-123.
Romaní J, Caixàs A, Carrascosa JM, et al. Effect of narrowband ultraviolet B therapy on inflammatory markers and body fat composition in moderate to severe psoriasis. Br J Dermatol. 2012;166:1237-1244.
Diehl JW, Chiu MW. Effects of ambient sunlight and photoprotection on vitamin D status. Dermatol Ther. 2010;23:48-60.
Armas LA, Dowell S, Akhter M, et al. Ultraviolet-B radiation increases serum 25-hydroxyvitamin D levels: the effect of UVB dose and skin color. J Am Acad Dermatol. 2007;57:588-593.
Olds WJ, McKinley AR, Moore MR, et al. In vitro model of vitamin D₃ (cholecalciferol) synthesis by UV radiation: dose-response relationships. J Photochem Photobiol B. 2008;93:88-93.