Cost effectiveness of home ultraviolet B phototherapy for psoriasis: economic evaluation of a randomised controlled trial (PLUTO study)
Abstract
Objective
To assess the costs and cost effectiveness of phototherapy with
ultraviolet B light provided at home compared with outpatient
ultraviolet B phototherapy for psoriasis.
Design
Cost utility, cost effectiveness, and cost minimisation analyses
performed alongside a pragmatic randomised clinical trial (the PLUTO
study) at the end of phototherapy (mean 17.6 weeks) and at one year
after the end of phototherapy (mean 68.4 weeks).
Setting Secondary care, provided by a dermatologist in the Netherlands.
Participants
196 adults with psoriasis who were clinically eligible for narrowband
(TL-01) ultraviolet B phototherapy were recruited from the dermatology
departments of 14 hospitals and were followed until the end of
phototherapy. From the end of phototherapy onwards, follow-up was
continued for an unselected, consecutive group of 105 patients for one
year after end of phototherapy.
Interventions
Ultraviolet B phototherapy provided at home (intervention) and
conventional outpatient ultraviolet B phototherapy (control) in a
setting reflecting routine practice in the Netherlands. Both treatments
used narrowband ultraviolet B lamps (TL-01).
Main outcome measures
Total costs to society, quality adjusted life years (QALYs) as
calculated using utilities measured by the EQ-5D questionnaire, and the
number of days with a relevant treatment effect (≥50% improvement of the
baseline self administered psoriasis area and severity index (SAPASI)).
Results
Home phototherapy is at least as effective and safe as outpatient
phototherapy, therefore allowing cost minimisation analyses (simply
comparing costs). The average total costs by the end of phototherapy
were €800 for home treatment and €752 for outpatient treatment, showing
an incremental cost per patient of €48 (95% CI €−77 to €174). The
average total costs by one year after the end of phototherapy were €1272
and €1148 respectively (difference €124, 95% CI €−155 to €403). Cost
utility analyses revealed that patients experienced equal health
benefits—that is, a gain of 0.296 versus 0.291 QALY (home v
outpatient) by the end of phototherapy (difference 0.0052, −0.0244 to
0.0348) and 1.153 versus 1.126 QALY by one year after the end of
phototherapy (difference 0.0267, −0.024 to 0.078). Incremental costs per
QALY gained were €9276 and €4646 respectively, both amounts well below
the normally accepted standard of €20 000 per QALY. Cost effectiveness
analyses indicated that the mean number of days with a relevant
treatment effect was 42.4 versus 55.3 by the end of phototherapy
(difference −12.9, −23.4 to −2.4). By one year after the end of
phototherapy the number of days with a relevant treatment effect were
216.5 and 210.4 respectively (6.1, −41.1 to 53.2), yielding an
incremental cost of €20 per additional day with a relevant treatment
effect.
Conclusions Home ultraviolet B
phototherapy for psoriasis is not more expensive than phototherapy in an
outpatient setting and proved to be cost effective. As both treatments
are at least equally effective and patients express a preference for
home treatment, the authors conclude that home phototherapy should be
the primary treatment option for patients who are eligible for
phototherapy with ultraviolet B light.
Trial registration Current Controlled Trials ISRCTN83025173 and Clinicaltrials.gov NCT00150930
Edited from bmj.com
Picture from dermclinic.co.uk
#psoriasis #ultraviolet
