Gout
Conditions
Keywords
Hyperuricemia, Tophi, Tophus, Drug Therapy
Brief summary
The purpose of this study is to determine the inter- and intra-rater reproducibility of direct physical measurement of tophus nodules in subjects with gout.
Detailed description
Gout is a chronic urate crystal deposition disorder. Left untreated, gout may result in progressive disease characterized by joint and bone destruction from tophaceous deposits and renal impairment due to gouty nephropathy. Hyperuricemia, defined as a serum urate concentration greater than 7.0 milligrams per deciliter (mg/dL), is the underlying metabolic aberration leading to urate crystal deposition in gout. Gout has several clinical presentations, including: recurrent acute attacks of inflammatory arthritis; deposition of monosodium urate monohydrate crystals in joints, bones and even parenchymal organs (tophaceous gout); renal impairment; and uric acid nephrolithiasis.1 As serum urate levels increase beyond greater than 7.0 mg/dL, the risks for gouty arthritis or for renal calculi increase. Febuxostat is a 2-aryl-thiazole derivative chemically engineered as a novel xanthine oxidase/dehydrogenase inhibitor. Febuxostat is being developed as an orally administered agent for the management of hyperuricemia in patients with gout. Subjects with palpable tophi \>10 millimeters (mm) in length and width and as round as possible will have the tophus measured on two separate visits by two different raters to assess the inter- and intra-rater reproducibility of direct physical measurement.
Interventions
OTHERMeasurement of Tophi to validate procedure
Intra- and Inter-rater Reproducibility measurements of the area (in mm2) of each tophus nodule.
Sponsors
Takeda
Study design
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
* Must have at least 1 palpable gouty tophus nodule in the foot/ankle, hand/wrist, or elbow, confirmed as gouty by prior diagnosis according to ACR criteria. * The tophus must be solid, round, non-tender, intact, and larger than 10mm in both length and width. * Joints nearest and immediately adjacent to the selected tophus must not be acutely inflamed. * Must be on stable treatment for gout with no medication changes in the past 30 days.
Exclusion criteria
* Must be able to return to the clinical site within 10 days. * Must not have allergy to ink.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Average Percent Difference in Area Between Visits | Visit 1 (Day 1) and Visit 2 (Days 6-11) | The rater measured length and width (mm) of the tophus at 2 visits separated by no more than 10 days. Area of the tophus was summarized using average percent difference, calculated as absolute difference of Visits 1 and 2 divided by the average of Visits 1 and 2 for the same tophus, pooled across raters. |
| Average Percent Difference in Area Between Raters | Visit 1 (Day 1 ) and Visit 2 (Day 6-11) | Each rater measured length and width (mm) of the tophus at 2 visits separated by no more than 10 days. Area of the tophus was summarized using the average percent difference, calculated as the absolute difference of Raters 1 and 2 divided by the average of Raters 1 and 2 for the same tophus, pooled across visits. |
Participant flow
Recruitment details
Subjects were enrolled at 2 study sites in the United States from 19 November 2002 to 09 January 2003.
Participants by arm
| Arm | Count |
|---|---|
| Tophi Participants Participants with palpable tophi \>10 millimeters (mm) in length and width and as round as possible measured on two separate visits by two different raters. | 13 |
| Total | 13 |
Baseline characteristics
| Characteristic | Tophi Participants |
|---|---|
| Age Continuous | 60.5 years STANDARD_DEVIATION 14.1 |
| Age, Customized 18 years to 35 years | 0 participants |
| Age, Customized 36 years to 50 years | 2 participants |
| Age, Customized 51 years to 65 years | 6 participants |
| Age, Customized 66 years to 85 years | 5 participants |
| Race/Ethnicity, Customized Asian | 1 participants |
| Race/Ethnicity, Customized Black or African American | 7 participants |
| Race/Ethnicity, Customized White | 5 participants |
| Sex: Female, Male Female | 2 Participants |
| Sex: Female, Male Male | 11 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 0 / 13 |
| serious Total, serious adverse events | 0 / 13 |
Outcome results
Primary
Average Percent Difference in Area Between Raters
Each rater measured length and width (mm) of the tophus at 2 visits separated by no more than 10 days. Area of the tophus was summarized using the average percent difference, calculated as the absolute difference of Raters 1 and 2 divided by the average of Raters 1 and 2 for the same tophus, pooled across visits.
Time frame: Visit 1 (Day 1 ) and Visit 2 (Day 6-11)
Population: Measurements of 52 tophi were obtained at 2 separate visits separated by no more than 10 days from the 13 subjects enrolled.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Tophi Participants | Average Percent Difference in Area Between Raters | Average Percent Difference | 32 mm² | Standard Deviation 27 |
Primary
Average Percent Difference in Area Between Visits
The rater measured length and width (mm) of the tophus at 2 visits separated by no more than 10 days. Area of the tophus was summarized using average percent difference, calculated as absolute difference of Visits 1 and 2 divided by the average of Visits 1 and 2 for the same tophus, pooled across raters.
Time frame: Visit 1 (Day 1) and Visit 2 (Days 6-11)
Population: Measurements of 52 tophi were obtained at 2 separate visits separated by no more than 10 days from the 13 subjects enrolled. Change in tophus size over 10 days was not expected.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Tophi Participants | Average Percent Difference in Area Between Visits | Average Percent Difference | 29 mm² | Standard Deviation 33 |