A comparative study of different treatment frequencies of psoralen and ultraviolet A in psoriatic patients with darker skin types (randomized-controlled study)

Frequency of phototherapy for treating psoriasis: a systematic review

INTRODUCTION

Narrow band ultraviolet B (NB-UVB) and psoralen-ultraviolet A (PUVA) remain inexpensive and effective anti-psoriatic therapies adopted worldwide with different frequency protocols. We aimed to systematically assess the evidence on the effects of different frequency protocols of phototherapy in treating psoriasis.

EVIDENCE ACQUISITION

We used the following terms, namely "photochemotherapy", "phototherapy", "psoriasis", "UVB", "UVA" and "ultraviolet therapy", to search the Cochrane Controlled Register of Trials, MEDLINE and Embase databases on August 1, 2019. We organized results using a PRISM diagram and analyzed bias risks with RoB-2 tool.

EVIDENCE SYNTHESIS

We included five randomized controlled trials (RCTs) on oral PUVA and three RCTs on NB-UVB. The five studies on PUVA included a total of 1452 patients with plaque psoriasis and did not find any significant difference in efficacy comparing two- vs. three- vs. four times weekly protocols. The three studies on NB-UVB included a total of 248 patients with plaque psoriasis. No differences in efficacy were reported in comparing different frequencies in delivering NB-UVB, namely twice vs. thrice weekly, twice vs. four times weekly, and thrice- vs. five times weekly protocols. Although protocols with higher treatments frequency per week achieved clearance faster than lower frequency ones, but they did not differ in terms of efficacy.

CONCLUSIONS

PUVA and NB-UVB remain an effective anti-psoriatic treatment; however further studies are needed to elucidate which protocol may be more effective in different skin phototypes.

Systematic review of UV-based therapy for psoriasis

BACKGROUND

UV-based therapies, which include narrow-band (NB) UVB, broad-band (BB) UVB, and psoralen and UVA (PUVA), are well known treatment options for moderate to severe plaque psoriasis. However, there are limited evidence-based reviews on their efficacy, short-term safety, and tolerability.

AIM

The aim of the study was to evaluate the efficacy, short-term safety, and tolerability of UV-based therapy in the treatment of adults with moderate to severe plaque psoriasis.

METHODS

We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) evaluating NB-UVB, BB-UVB, and PUVA in adults with moderate to severe plaque-type psoriasis. Our efficacy outcomes were ≥ Psoriasis Area and Severity Index (PASI)-75 and clearance. We evaluated the short-term safety and tolerability from the percentage of adverse effects and withdrawal due to adverse effects, respectively.

RESULTS

Forty-one RCTs, with a total of 2,416 patients, met the eligibility criteria and were included in the analysis. In regard to PASI-75 in monotherapy trials, PUVA (mean: 73 %, 95 % CI 56-88) was the most effective modality. Trials with BB-UVB also showed a high PASI-75 (73 %) but with a wide CI (18-98) due to heterogeneity of the total available three studies. This was followed by NB-UVB (mean: 62 %, 95 % CI 45-79) then bath PUVA (mean: 47 %, 95 % CI 30-65). In regard to clearance in the monotherapy trials, PUVA (mean: 79 %, 95 % CI 69-88) was superior to NB-UVB (mean: 68 %, 95 % CI 57-78), BB-UVB (mean: 59 %, 95 % CI 44-72), and bath PUVA (mean: 58 %, 95 % CI 44-72). The percentages of asymptomatic erythema development in monotherapy trials were 64 % for BB-UVB, 57 % for NB-UVB, 45 % for PUVA, and 34 % for bath PUVA. Symptomatic erythema or blistering percentages for the monotherapy trials were as follows: 7.8 % for NB-UVB, 2 % for BB-UVB, 17 % for PUVA, and 21 % for bath PUVA. The percentages of withdrawal due to adverse effects were 2 % for NB-UVB, 4.6 % for BB-UVB, 5 % for PUVA, and 0.7 % for bath PUVA monotherapy trials.

CONCLUSIONS

As a monotherapy, PUVA was more effective than NB-UVB, and NB-UVB was more effective than BB-UVB and bath PUVA in the treatment of adults with moderate to severe plaque-type psoriasis, based on clearance as an end point. Based on PASI-75, the results were similar except for BB-UVB, which showed a high mean PASI-75 (73 %) that was similar to PUVA, but with a wide CI (18-98). The short-term adverse effects were mild as shown by the low rate of withdrawal due to adverse effects.

A review of phototherapy protocols for psoriasis treatment

Phototherapy is a mainstay in the treatment of psoriasis and is available as psoralen plus UVA (PUVA), broadband UVB (BB-UVB), and narrowband UVB (NB-UVB). Phototherapy can be administered in the hospital, outpatient clinic, or in the patient's home. The purpose of this review is to provide some practical guidance to general dermatologists and residents on the specifics of using phototherapy, which, despite its decreasing use, remains one of our most safe and effective treatment strategies for psoriasis care. We conducted a literature review of home phototherapy, BB-UVB, NB-UVB, and PUVA phototherapy using PubMed, MD Consult, and reference lists. A variety of protocols for BB-UVB, NB-UVB, and PUVA have been used in clinical trials. NB-UVB is more effective than BB-UVB and safer than PUVA. Typical regimens for NB-UVB involve dosing 3 times per week for at least 3 months. Treatment must be independently developed to suit each participant's needs. Ultraviolet light is an effective, relatively safe modality that is a valuable tool in the treatment of psoriasis. NB-UVB phototherapy is considered the first-line treatment for extensive plaque type psoriasis.

Comparison of turbo-PUVA and conventional American-style PUVA in the treatment of psoriatic patients

BACKGROUND

Ultraviolet (UV)A protective properties of dihydroxyacetone (DHA) have been used as a topical UV-resisting barrier to optimize psoralens and UVA (turbo-PUVA). Starting doses and increments were based on the DHA diffuse reflectance spectroscopy-derived protection factor.

OBJECTIVE

To evaluate the efficacy of turbo-PUVA in psoriatic patients using a simpler method for determining starting doses and increments, in comparison to the conventional American-style PUVA photochemotherapy.

METHODS

Thirty psoriasis patients (15 on American-style PUVA and 15 on turbo-PUVA) were evaluated, each receiving PUVA twice weekly. Starting UVA dose was determined according to skin phototype for the American-style PUVA group and according to the patient's skin phototype x DHA SPF 3 in turbo-PUVA group. UVA increments used were 0.5-1.5 J/cm(2) per treatment in American-style PUVA and 25% of the previous dose in turbo-PUVA.

RESULTS

Turbo-PUVA group showed a significantly lower mean cumulative dose, a significantly higher psoriasis area and severity index score reduction, lesser mean number of treatment sessions, and less duration of treatment till remission (188.44+/-106.2 J/cm(2), 92.164+/-1.975%, 11.2+/-3.52 session, and 1.4+/-0.44 months, respectively) than conventional American-style PUVA group (255.13+/-18.304 J/cm(2), 74.725+/-10.976%, 30+/-0.00 sessions, and 3.75+/-0.00 months, respectively).

CONCLUSION

Turbo-PUVA is more effective and time convenient for the treatment of psoriasis with less cumulative dose than the conventional American-style PUVA.