Duloxetine is an FDA‐approved treatment for both osteoarthritis (OA) pain and depression, but uptake of duloxetine in knee OA management varies. We examined the cost‐effectiveness of adding duloxetine to knee OA care with or without depression screening. We used the Osteoarthritis Policy Model, a validated computer microsimulation of knee OA, to examine the value of duloxetine for knee OA patients with moderate pain by comparing three strategies:
- Usual care (UC)
- Duloxetine for those who screen positive for depression on the Patient Health Questionnaire 9 (PHQ‐9) + UC
- Universal duloxetine + UC
Outcomes included quality‐adjusted life years (QALYs), lifetime direct medical costs, and incremental cost‐effectiveness ratios (ICERs), discounted at 3% annually. Model inputs, drawn from published literature and national databases, included: annual cost of duloxetine, $721‐$937; average pain reduction for duloxetine, 17.5 points on the WOMAC pain scale (0‐100); likelihood of depression remission with duloxetine, 27.4%. The screening strategy led to an additional 17 QALYs per 1,000 subjects and increased costs by $289/subject (ICER=$17,000/QALY). Universal duloxetine led to an additional 31 QALYs per 1,000 subjects and $1,205/subject (ICER=$39,300/QALY).
In conclusion, adding duloxetine to usual care for knee OA patients with moderate pain, regardless of depressive symptoms, is cost‐effective at frequently‐used WTP thresholds.