A five-year model to assess the early cost-effectiveness of new diagnostic tests in the early diagnosis of rheumatoid arthritis.
Arthritis Res Ther
; 18(1): 135, 2016 06 10.
Article
in En
| MEDLINE
| ID: mdl-27287375
BACKGROUND: There is a lack of information about the sensitivity, specificity and costs new diagnostic tests should have to improve early diagnosis of rheumatoid arthritis (RA). Our objective was to explore the early cost-effectiveness of various new diagnostic test strategies in the workup of patients with inflammatory arthritis (IA) at risk of having RA. METHODS: A decision tree followed by a patient-level state transition model, using data from published literature, cohorts and trials, was used to evaluate diagnostic test strategies. Alternative tests were assessed as add-on to or replacement of the ACR/EULAR 2010 RA classification criteria for all patients and for intermediate-risk patients. Tests included B-cell gene expression (sensitivity 0.60, specificity 0.90, costs 150), MRI (sensitivity 0.90, specificity 0.60, costs 756), IL-6 serum level (sensitivity 0.70, specificity 0.53, costs 50) and genetic assay (sensitivity 0.40, specificity 0.85, costs 750). Patients with IA at risk of RA were followed for 5 years using a societal perspective. Guideline treatment was assumed using tight controlled treatment based on DAS28; if patients had a DAS28 >3.2 at 12 months or later patients could be eligible for starting biological drugs. The outcome was expressed in incremental cost-effectiveness ratios (2014 per quality-adjusted life year (QALY) gained) and headroom. RESULTS: The B-cell test was the least expensive strategy when used as an add-on and as replacement in intermediate-risk patients, making it the dominant strategy, as it has better health outcomes and lower costs. As add-on for all patients, the B-cell test was also the most cost-effective test strategy. When using a willingness-to-pay threshold of 20,000 per QALY gained, the IL-6 and MRI strategies were not cost-effective, except as replacement. A genetic assay was not cost-effective in any strategy. Probabilistic sensitivity analysis revealed that the B-cell test was consistently superior in all strategies. When performing univariate sensitivity analysis for intermediate-risk patients, specificity and DAS28 in the B-cell add-on strategy, and DAS28 and sensitivity in the MRI add-on strategy had the largest impact on the cost-effectiveness. CONCLUSIONS: This early cost-effectiveness analysis indicated that new tests to diagnose RA are most likely to be cost-effective when the tests are used as an add-on in intermediate-risk patients, and have high specificity, and the test costs should not be higher than 200-300.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Arthritis, Rheumatoid
/
Cost-Benefit Analysis
/
Early Diagnosis
Type of study:
Diagnostic_studies
/
Guideline
/
Health_economic_evaluation
/
Prognostic_studies
/
Screening_studies
Aspects:
Patient_preference
Limits:
Humans
Language:
En
Journal:
Arthritis Res Ther
Journal subject:
REUMATOLOGIA
Year:
2016
Document type:
Article
Affiliation country:
Netherlands
Country of publication:
United kingdom