Home versus outpatient ultraviolet B phototherapy for mild to severe psoriasis: pragmatic multicentre randomised controlled non-inferiority trial (PLUTO study)

Abstract

Objective: To determine whether ultraviolet B phototherapy at home is equally safe and equally effective as ultraviolet B phototherapy in an outpatient setting for patients with psoriasis.

Design: Pragmatic multicentre single blind randomised clinical trial (PLUTO study).

Setting: Dermatology departments of 14 hospitals in the Netherlands.

Participants: 196 patients with psoriasis who were clinically eligible for narrowband (TL-01) ultraviolet B phototherapy. The first 105 consecutive patients were also followed for one year after therapy.

Intervention: Ultraviolet B phototherapy at home using a TL-01 home phototherapy unit compared with standard narrowband ultraviolet B phototherapy in an outpatient setting. Both therapies were done in a setting reflecting routine daily practice in the Netherlands.

Main outcome measures: The main outcome measure was effectiveness as measured by the proportion of patients with a 50% or more reduction of the baseline psoriasis area and severity index (PASI) or self administered psoriasis area and severity index (SAPASI), called the PASI 50 and SAPASI 50 (relevant treatment effect). Another outcome of effectiveness was the percentage reduction in median scores on the PASI as well as SAPASI. Also the proportions of patients reaching the PASI 75 and SAPASI 75 (successful treatment effect), and the PASI 90 and SAPASI 90 (almost complete clearance) were calculated. Other secondary outcomes were quality of life (SF-36, psoriasis disability index), burden of treatment (questionnaire), patients' preferences and satisfaction (questionnaire), and dosimetry and short term side effects (diary).

Results: 82% of the patients treated at home compared with 79% of the patients treated in an outpatient setting reached the SAPASI 50 (difference 2.8%, 95% confidence interval -8.6% to 14.2%), and 70% compared with 73% reached the PASI 50 (-2.3%, -15.7% to 11.1%). For patients treated at home the median SAPASI score decreased 82% (from 6.7 to 1.2) and the median PASI score decreased 74% (from 8.4 to 2.2), compared with 79% (from 7.0 to 1.4) and 70% (from 7.0 to 2.1) for patients treated in an outpatient setting. Treatment effect as defined by the mean decline in PASI and SAPASI scores was significant (P<0.001) and similar across groups (P>0.3). Total cumulative doses of ultraviolet B light were similar (51.5 v 46.1 J/cm(2), difference 5.4, 95% confidence interval -5.2 to 16.0), and the occurrence of short term side effects did not differ. The burden of undergoing ultraviolet B phototherapy was significantly lower for patients treated at home (differences 1.23 to 3.01, all P</=0.001). Quality of life increased equally regardless of treatment, but patients treated at home more often rated their experience with the therapy as "excellent" (42%, 38/90) compared with patients treated in the outpatient department (23%, 20/88; P=0.001).

Conclusion: Ultraviolet B phototherapy administered at home is equally safe and equally effective, both clinically and for quality of life, as ultraviolet B phototherapy administered in an outpatient setting. Furthermore, ultraviolet B phototherapy at home resulted in a lower burden of treatment and led to greater patients' satisfaction. Trial registration Current Controlled Trials ISRCTN83025173 and Clinicaltrials.gov NCT00150930.

Fig 1 Schematic representation of planned measurements. PASI=psoriasis area and severity index; SAPASI=self administered psoriasis area and severity index

Fig 2 Flow of patients through trial

Fig 3 Median self administered psoriasis area and severity index (SAPASI) scores against time. 0=baseline (98 home patients v 98 outpatients); 1=start of therapy (93 v 94), 2=23 irradiations (90 v 74), 3=end of therapy (when ultraviolet B treatment exceeded 46 irradiations, the 46th irradiation was defined as end of therapy; 94 v 91), 4=2 months after therapy (51 v 43), 5=4 months after therapy (52 v 44), 6=6 months after therapy (50 v 44), 7=8 months after therapy (50 v 43), 8=10 months after therapy (49 v 42), 9=12 months after therapy (47 v 40). From measurement 0-3 all 196 participants were followed. From measurement 4-9 only a consecutive sample of 105 participants was followed

Fig 4 Mean burden of treatment values on a 0-10 visual analogue scale for 92 patients randomised to receive ultraviolet B phototherapy at home and 89 to receive ultraviolet B phototherapy in an outpatient setting. Error bars are 95% confidence intervals. *For example, location of treatment (home v hospital), positioning for irradiation, actions for patient to perform. †Includes use of creams and ointments or taking drugs for psoriasis (87 home patients v 83 outpatients)

Fig 5 Patients’ self rated global experience of ultraviolet B phototherapy