Comparison of low dose weekly with high dose weekly incremental protocols of narrow band ultraviolet B treatment in psoriasis

Narrow band UVB therapy has been widely used in psoriasis recent years. Although there are various protocols for the treatment, there is no agreement on a certain protocol.The aim of this study is to compare low dose weekly increment with high dose weekly increment of narrow band UVB treatment in psoriasis patients.In the study, 22 psoriasis patients, taking narrow band UVB therapy 3 times weekly were randomly selected in 2 groups. Low dose weekly increment was applied to one group (11 patients) and high dose weekly increment was applied to the second group (11 patients). Assessments were made weekly by using PASI scores (psoriasis area severity index) for 12 weeks.The mean PASI scores of the groups were compared before the treatment and at the end of each week through the treatment protocol. There was not a statistically significant difference in the number of the patients who recovered, in the number of the patients that reached PASI 50 and PASI 75, and also in the time necessary to reach the PASI 50 and PASI 75 between the two groups at the end of the 12 weeks? therapy (p>0.05). The two groups were also compared for mean cumulative doses. The mean cumulative dose was greater in the high dose increment group, and the difference between the two groups was statistically significant (P = 0.016).As a conclusion, low dose weekly increment protocol was as efficacious as high dose weekly increment protocol in the psoriasis treatment with narrow band UVB. However, there was less cumulative dose UVB. The lower increment doses can diminish acute and chronic side effects; thus, it could be a reason for preference in the psoriasis therapy. But our results should be confirmed by studies including large number of cases.