Cost-effectiveness of licensed treatment options for restless legs syndrome in the UK and Sweden

ABSTRACT

Objective: To estimate the cost-effectiveness of pramipexole versus no treatment and ropinirole in moderate to very severe idiopathic restless legs syndrome (RLS) in the UK and Sweden.

Methods: A Markov model was developed using clinical trial data for pramipexole and ropinirole. Model health states were based on the International RLS Study Group Rating Scale (IRLS) scores. Health states were: no (IRLS 0), mild (IRLS 1–14), moderate (IRLS 15–24), severe (IRLS 25–34), very severe RLS (IRLS 35–40) and death. Patients entered the model with an IRLS score > 15 matching the trial inclusion criteria of the pramipexole trials. Resource use and utilities were based on trial data, literature, a patient survey and a panel of physicians from the UK and Sweden in the absence of published information. A healthcare sector perspective was taken for the UK and a societal perspective for Sweden using 2004–2005 unit costs. The base case analysis took a 1-year timeframe.

Results: In the UK the incremental cost per quality-adjusted life year (QALY) for pramipexole was £3349 versus no treatment and a cost-saving of £92 against ropinirole. In Sweden, pramipexole produced cost-savings of Swedish Krona (SEK) 2381 (£176) versus no treatment and SEK 3564 (£264) against ropinirole. QALY gains in both countries were 0.095 versus no treatment and 0.007 versus ropinirole. Results compare well with UK cost–effectiveness thresholds of £20 000/£30 000 per QALY and are cost-saving for Sweden. One-way and probabilistic sensitivity analyses showed results to be robust.

Conclusions: Pramipexole is cost-effective compared to no treatment and ropinirole for patients with moderate to very severe RLS.

Key words: :

• Cost-utility
• Dopamine agonists
• Pramipexole
• Restless legs syndrome (RLS)
• Ropinirole

Acknowledgements

Declaration of interest: This study was sponsored by Boehringer Ingelheim GmbH, Germany.

The RLS Health Economic Study Group participants are Dr Ray Chaudhuri (Department of Neurology, King's College Hospital, London, UK); Dr Donald Grossett and Dr Graeme MacPhee (Southern General Hospital, Glasgow, UK); Mr Martin King (Papworth Sleep Laboratory, Cambridge, UK); Dr Julian Spinks (general practitioner, Kent, UK); Dr Adrian Williams (Guy's and Thomas Hospital, London, UK); Professor Anthony Schapira (University Department of Clinical Neurosciences, Institute of Neurology, UCL, London, UK) and Associate Professor Jan Ulfberg (Inland Hospital, Tynset, Norway previously at Avesta Hospital Sweden).

The authors wish to thank Prof. Paul Kind from the Centre for Health Economics, University of York for his assistance with estimating the utilities for the baseline model. In addition, the authors thank Prof. Andrew Briggs, Section of Public Health and Health Policy, University of Glasgow for his advice on the model and Eugena Stamuli of Oxford Outcomes for her assistance in statistical analyses of the trial data.

We thank the reviewers for their helpful comments to improve this article.

Appendix 1.  Questions 14 and 16–18 of the Johns Hopkins Restless Legs Syndrome Quality of Life Questionnaire (RLSQoL)48