| Literature DB >> 35072722 |
Daniel I Rhon1,2, Minchul Kim3, Carl V Asche3, Stephen C Allison1, Chris S Allen4, Gail D Deyle1.
Abstract
Importance: Physical therapy and glucocorticoid injections are initial treatment options for knee osteoarthritis, but available data indicate that most patients receive one or the other, suggesting they may be competing interventions. The initial cost difference for treatment can be substantial, with physical therapy often being more expensive at the outset, and cost-effectiveness analysis can aid patients and clinicians in making decisions. Objective: To investigate the incremental cost-effectiveness between physical therapy and intra-articular glucocorticoid injection as initial treatment strategies for knee osteoarthritis. Design, Setting, and Participants: This economic evaluation is a secondary analysis of a randomized clinical trial performed from October 1, 2012, to May 4, 2017. Health economists were blinded to study outcomes and treatment allocation. A randomized sample of patients seen in primary care and physical therapy clinics with a radiographically confirmed diagnosis of knee osteoarthritis were evaluated from the clinical trial with 96.2% follow-up at 1 year. Interventions: Physical therapy or glucocorticoid injection. Main Outcomes and Measures: The main outcome was incremental cost-effectiveness between 2 alternative treatments. Acceptability curves of bootstrapped incremental cost-effectiveness ratios (ICERs) were used to identify the proportion of ICERs under the specific willingness-to-pay level ($50 000-$100 000). Health care system costs (total and knee related) and health-related quality-of-life based on quality-adjusted life-years (QALYs) were obtained.Entities:
Mesh:
Substances:
Year: 2022 PMID: 35072722 PMCID: PMC8787617 DOI: 10.1001/jamanetworkopen.2021.42709
Source DB: PubMed Journal: JAMA Netw Open ISSN: 2574-3805
Descriptive and Demographic Variables of the 2 Groups at Baseline
| Variable | All (n = 156) | Physical therapy (n = 78) | Glucocorticoid injection (n = 78) |
|---|---|---|---|
| Continuous variables, mean (SD) | |||
| Age, y | 56.1 (8.7) | 56.3 (9.2) | 56.0 (8.2) |
| BMI | 31.5 (5.6) | 31.4 (5.1) | 31.6 (6.1) |
| Baseline WOMAC score (total score) | 108.0 (44.7) | 108.8 (47.1) | 107.1 (42.4) |
| Duration of symptoms, mo | 92.5 (107.2) | 100.0 (122.7) | 85.0 (89.2) |
| Categorical variables, No. (%) | |||
| Sex | |||
| Male | 81 (51.9) | 41 (52.6) | 40 (51.3) |
| Female | 75 (48.1) | 37 (47.4) | 38 (48.7) |
| Smoker | 8 (5.1) | 5 (6.4) | 3 (3.8) |
| Beneficiary category | |||
| Active duty | 41 (26.2) | 20 (25.6) | 21 (26.9) |
| Retired service member | 54 (34.6) | 28 (35.9) | 26 (33.3) |
| Family member or dependent | 61 (39.1) | 29 (37.2) | 32 (41.0) |
| Kellgren-Lawrence grade | |||
| 1 | 6 (3.8) | 5 (6.4) | 1 (1.3) |
| 2 | 68 (43.6) | 26 (33.3) | 42 (53.8) |
| 3 | 59 (37.8) | 34 (43.6) | 25 (32.1) |
| 4 | 23 (14.7) | 13 (16.7) | 10 (12.8) |
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); WOMAC, Western Ontario and McMaster Universities Arthritis Index.
Includes reserve or national guard on active duty.
Radiographic measures of severity are as follows: grade 1, doubtful joint space narrowing and possible osteophytic lipping; grade 2, definite osteophytes and possible joint space narrowing; grade 3, moderate multiple osteophytes, definite narrowing of joint space, and some sclerosis and possible deformity of bone ends; and grade 4, large osteophytes, marked narrowing of joint space, severe sclerosis, and definite deformity of bone ends.
Cost-effectiveness Analysis
| Variable | Physical therapy (n = 78) | Corticosteroid injection (n = 78) | Difference | Base case ICER, $ | Bootstrapped ICER, | Acceptability, % | INMB (WTP threshold of $100 000), $ | |||
|---|---|---|---|---|---|---|---|---|---|---|
| WTP threshold of $0 | WTP threshold of $50 000 | WTP threshold of $100 000 | ||||||||
| QALYs (95% CI) | 0.76 (0.73 to 0.80) | 0.69 (0.65 to 0.72) | 0.08 (0.02 to 0.13) | .003 | NA | NA | NA | NA | NA | NA |
| Knee-related cost (95% CI) | 2449 (1893 to 3004) | 1834 (1454 to 2213) | 615 (–34 to 1263) | .06 | 8103 | 8782 (1540 to 34 975) | 0.3 | 98.5 | 99.2 | 6955 |
| Total medical cost (95% CI) | 8921 (7208 to 10 634) | 6776 (5476 to 8074) | 2145 (12 to 4279) | .049 | 28 271 | 35 527 (1318 to 206 319) | 2.0 | 82.7 | 97.2 | 5535 |
Abbreviations: ICER, incremental cost-effectiveness ratio; NA, not applicable; INMB, incremental net monetary benefit; QALYs, quality-adjusted life-years; WTP, willingness to pay.
The bootstrapping method with 1000 replications.
Generalized linear model controlling for age, body mass index, female sex, smoking status, and Kellgren-Lawrence radiographic severity score.
Generalized linear model with log link and γ distribution controlling for age, body mass index, female sex, smoking status, and Kellgren-Lawrence radiographic severity score.
Figure 1. Cost-effectiveness Planes and Acceptability Curves for Knee-Related Costs
Filled circles indicate the incremental cost-effectiveness ratios, with the solid blue line showing the mean incremental cost-effectiveness ratio. Dotted lines indicate 95% CIs. WTP indicates willingness to pay; QALY, quality-adjusted life-year.
Figure 2. Cost-effectiveness Planes and Acceptability Curves for Total Medical Costs (Medical Care for Any Reason)
Filled circles indicate the incremental cost-effectiveness ratios, with the solid blue line showing the mean incremental cost-effectiveness ratio. Dotted lines indicate 95% CIs. WTP indicates willingness to pay; QALY, quality-adjusted life-year.
Figure 3. Monetary Net Benefit (MNB) Threshold
Dotted lines indicate 95% CIs. WTP indicates willingness to pay.