Cost utility analysis of sildenafil compared with papaverine-phentolamine injections

Objective To compare the cost effectiveness of sildenafil and papaverine-ph entolamine injections for treating erectile dysfunction. Design Cost utility analysis comparing treatment with sildenafil (allowing a switch to injection therapy) and treatment with papaverine-phentolamine ( no switch allowed). Costs and effects were estimated from the societal pers pective, Using time trade-off, a sample of the general public (n = 169) val ued health states relating to erectile dysfunction. These values were used to estimated health related quality of life by converting the clinical outc omes of a trial into quality adjusted life years (QALYSs). Participants 169 residents of Rotterdam. Main outcome measures Cost per quality adjusted life year. Results Participants thought that erectile dysfunction limits quality of li fe considerably: the mean utility gain attributable to sildenafil is 0.11. Overall, treatment with sildenafil gained more QALYs, but the total costs w ere higher. The incremental cost effectiveness ratio for the introduction o f sildenafil was pound 3639 in the first year and fell in following years. Doubling the frequency of use of sildenafil almost doubled the cost per add itional QALY: Conclusions Treatment with sildenafil is cost effective. When considering f unding sildenafil, healthcare systems should take into account that the fre quency of use affects cost effectiveness.