Cost-Effectiveness of Tramadol and Oxycodone in the Treatment of Knee Osteoarthritis.
OBJECTIVE
To evaluate the cost-effectiveness of incorporating tramadol or oxycodone into knee osteoarthritis (OA) treatment.


METHODS
We used the Osteoarthritis Policy Model to evaluate long-term clinical and economic outcomes of knee OA patients with a mean age of 60 years with persistent pain despite conservative treatment. We evaluated 3 strategies: opioid-sparing (OS), tramadol (T), and tramadol followed by oxycodone (T+O). We obtained estimates of pain reduction and toxicity from published literature and annual costs for tramadol ($600) and oxycodone ($2,300) from Red Book Online. Based on published data, in the base case, we assumed a 10% reduction in total knee arthroplasty (TKA) effectiveness in opioid-based strategies. Outcomes included quality-adjusted life years (QALYs), lifetime cost, and incremental cost-effectiveness ratios (ICERs) and were discounted at 3% per year.


RESULTS
In the base case, T and T+O strategies delayed TKA by 7 and 9 years, respectively, and led to reduction in TKA utilization by 4% and 10%, respectively. Both opioid-based strategies increased cost and decreased QALYs compared to the OS strategy. Tramadol's ICER was highly sensitive to its effect on TKA outcomes. Reduction in TKA effectiveness by 5% (compared to base case 10%) resulted in an ICER for the T strategy of $110,600 per QALY; with no reduction in TKA effectiveness, the ICER was $26,900 per QALY. When TKA was not considered a treatment option, the ICER for T was $39,600 per QALY.


CONCLUSIONS
Opioids do not appear to be cost-effective in OA patients without comorbidities, principally because of their negative impact on pain relief after TKA. The influence of opioids on TKA outcomes should be a research priority.
Orthopaedic and Arthritis Center for Outcomes Research and Brigham and Women's Hospital, Boston, Massachusetts.
Savannah R
SR
Smith
Orthopaedic and Arthritis Center for Outcomes Research, Brigham and Women's Hospital, and Harvard Medical School, Boston, Massachusetts.
Jeffrey N
JN
Katz
Orthopaedic and Arthritis Center for Outcomes Research, Brigham and Women's Hospital, and Harvard Medical School, Boston, Massachusetts.
Jamie E
JE
Collins
Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts.
Daniel H
DH
Solomon
University of North Carolina, Chapel Hill.
Joanne M
JM
Jordan
Yale University, New Haven, and Veterans Affairs Medical Center, West Haven, Connecticut.
Lisa G
LG
Suter
University of California, San Francisco.
Edward H
EH
Yelin
Yale University, New Haven, Connecticut.
A
A
David Paltiel
Orthopaedic and Arthritis Center for Outcomes Research, Brigham and Women's Hospital, and Harvard Medical School, Boston, Massachusetts.
Elena
E
Losina
D000368:Aged; D000369:Aged, 80 and over; D000701:Analgesics, Opioid / Q000191:economics* / Q000627:therapeutic use*; D003198:Computer Simulation; D003362:Cost-Benefit Analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000188:drug therapy* / Q000191:economics*; D010098:Oxycodone / Q000191:economics / Q000627:therapeutic use*; D014147:Tramadol / Q000191:economics / Q000627:therapeutic use*
D000701:Analgesics, Opioid; D014147:Tramadol; D010098:Oxycodone