Cost-effectiveness of advising the use of topical or oral ibuprofen for knee pain; the TOIB study [ISRCTN: 79353052].

OBJECTIVE: Advice to use topical or oral NSAIDs is equally effective for the treatment of knee pain in older people. The ingredient cost of topical preparations is typically more than oral preparations, but could save costs because they have fewer adverse effects. A cost-utility study is needed to decide on their comparative cost effectiveness.

METHODS: We recruited 585 people aged >or=50 yrs with knee pain; 282 participated in a randomized controlled trial and 303 in a patient preference study from 26 MRC General Practice Research Framework practices in the UK. They received advice to preferentially use topical or oral NSAIDs for knee pain. We calculated the comparative cost per quality-adjusted life year (QALY) from both a National Health Service (NHS) and a societal perspective over 12 and 24 months.

RESULTS: Compared with the topical route, oral NSAIDs cost the NHS pound191 and pound72 more over 1 yr in the randomized trial and preference study, respectively. The cost per QALY, from an NHS perspective, was in the range of pound9000- pound12000 in the randomized trial. In the preference study, it was pound2564 over 1 yr, but over 2 yrs the oral route was dominant.

CONCLUSIONS: Our cost-effectiveness analysis supports the use of oral NSAIDs in selected patients. Nevertheless, deciding to recommend oral NSAIDs in preference to topical NSAIDs could have a substantial impact on NHS costs because of the uncertainty in the cost-effectiveness estimate.