A discrete-choice experiment of United Kingdom patients' willingness to risk adverse events for improved function and pain control in osteoarthritis

Summary

Objective

To assess patient preferences for treatment-related benefits and risks associated with the use of nonsteroidal anti-inflammatory drugs (NSAIDs) in the management of osteoarthritis (OA).

Design

Using a chronic-illness panel in the United Kingdom, patients 45 years or older with a self-reported diagnosis of OA were eligible to participate in the study. Patient preferences were assessed using a discrete-choice experiment that compared hypothetical treatment profiles of benefits and risks consistent with NSAID use. Benefit outcomes (ambulatory pain, resting pain, stiffness, and difficulty doing daily activities) were presented on a 0-to-100 mm scale. Risk outcomes (bleeding ulcer, stroke, and myocardial infarction [MI]) were expressed as probabilities over a fixed time period. Each patient answered 10 choice tasks comparing different treatment profiles. Preference weights were estimated using a random-parameters logit model.

Results

Final sample included 294 patients. Patients ranked reductions in ambulatory pain and difficulty doing daily activities (both: 6.32; 95% confidence interval [CI]: 5.0–7.6) as the most important benefit outcomes, followed by reductions in resting pain (2.80; 95% CI: 1.8–3.8) and stiffness (2.65; 95% CI: 0.9–4.4). Incremental changes (3%) in the risk of MI or stroke were assessed as the most important risk outcomes (10.00; 95% CI: 8.2–11.8; and 8.90; 95% CI: 7.3–10.5, respectively).

Conclusion

Patients ranked ambulatory pain as a more important benefit than resting pain; likely due to its impact on ability to do daily activities. For a 25-mm reduction, patients were willing to accept four times the risk of MI in ambulatory pain vs resting pain.