Study outcomes
| 12 months outcomes | 24 months outcomes | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Categorical study outcomes | ||||||||||||
| 2-monthly urate(n = 40) | Annual urate(n = 27) | RD(95% CI) | RR(95% CI) | p value | 2-monthly urate(n = 40) | Annual urate(n = 27) | RD(95% CI) | RR(95% CI) | p value | |||
| Urate ≤ 0.36 mmol/L | 35/40 (87.50%) | 22/27 (81.48%) | 0.06(–0.12 to 0.24) | 1.07(0.87 to 1.33) | 0.51 | 38/40 (95.00%) | 17/27 (62.96%) | 0.32(0.13 to 0.52) | 1.51(1.12 to 2.03) | 0.0021 | ||
| Tophaceous disease | 8/38 (21.05%)Tophus number 2.62 (2.67)Max size 10.87 (9.09) mm | 7/24 (29.16%)Tophus number 1.57 (1.13)Max size 9.00 (6.40) mm | –0.08(–0.30 to 0.14) | 0.72(0.30 to 1.73) | 0.55 | 7/39 (17.95%)Tophus number 1.71 (0.76)Max size 6.29 (7.27) mm | 4/21 (19.05%)Tophus number 2.00 (1.15)Max size 13.00 (9.09) mm | –0.01(–0.22 to 0.20) | 0.94(0.31 to 2.85) | > 0.99 | ||
| Any flares in past 12 months | 18/38 (47.37%) | 14/24 (58.33%) | –0.11(–0.36 to 0.14) | 0.81(0.50 to 1.30) | 0.44 | 3/39 (7.69%) | 7/21 (33.33%) | –0.26(–0.47 to –0.04) | 0.23(0.067 to 0.80) | 0.025 | ||
| Remission | 16/38 (42.11%) | 7/24 (29.17%) | 0.13(–0.11 to 0.37) | 1.44(0.70 to 2.99) | 0.42 | 29/39 (74.36%) | 13/21 (61.90%) | 0.12(–0.12 to 0.37) | 1.20(0.82 to 1.76) | 0.38 | ||
| Continuous study outcomes | ||||||||||||
| 2-monthly urate(n = 38) | Annual urate(n = 24) | Mean difference(95% CI) | p value | 2-monthly urate(n = 39) | Annual urate(n = 21) | Mean difference(95% CI) | p value | |||||
| Urate (mmol/L) | 0.29 (0.07) | 0.28 (0.07) | 0.010 (–0.026 to 0.046) | 0.59 | 0.25 (0.07) | 0.28 (0.08) | –0.03 (–0.070 to 0.010) | 0.14 | ||||
| Allopurinol dose (mg/day) | 429.73 (192.74) | 466.67 (127.40) | –36.94 (–125.96 to 52.08) | 0.41 | 405.41 (163.21) | 419.05 (169.17) | –13.64 (–103.19 to 75.91) | 0.76 | ||||
| Prescriptions issued (days/yr) | 336.81 (62.47)* | 299.70 (85.04)* | 37.11 (–1.11 to 73.10) | 0.044 | 348.97 (91.75)* | 274.43 (101.63)* | 74.54 (26.87 to 122.26) | 0.0033 | ||||
| Discrete study outcomes | ||||||||||||
| 2-monthly urate(n = 38) | Annual urate(n = 24) | Rate difference(95% CI) | p value | 2-monthly urate(n = 39) | Annual urate(n = 21) | Rate difference(95% CI) | p value | |||||
| GP appointments | 0.079 (0.36) | 0.042 (0.20) | 0.037 (–0.09 to 0.17) | 0.57 | 0.026 (0.16) | 0.048 (0.22) | –0.022 (–0.11 to 0.075) | 0.66 | ||||
| Flares | 0.79 (1.26) | 1.63 (1.81) | –0.84 (–1.37 to –0.30) | 0.0024 | 0.077 (0.27) | 0.62 (1.02) | –0.54 (–0.82 to –0.27) | 0.0001 | ||||
| Doses missed in last week | 0.45 (1.25) | 0.08 (0.28) | 0.36 (0.08 to 0.65) | 0.01 | 0.33 (0.93) | 1.29 (2.51) | –0.95 (–1.39 to –0.52) | < 0.0001 | ||||
Categorical study outcomes at the 12 month and 24 month study visits include the primary study outcome of proportion of participants achieving a urate target of ≤ 0.36 mmol/L at month 24. Results are reported as total number (percentage) then risk difference (RD) or relative risk (RR) with 95% confidence intervals (CI). An intention-to-treat analysis was performed with dropouts from the study assumed to have failed to meet urate target. Significance determined by Fishers exact test. Continuous outcomes for participants continuing in the study are given as the mean (standard deviation) with the mean difference (95% CI) and significance calculated using a two sample T test. Community prescribing data was available for all participants hence the number of participants for this analysis is n = 40 (2-monthly monitoring) and n = 27 (annual monitoring) with this difference indicated by (*). Discrete outcomes are given as mean (standard deviation) with the rate difference (95% CI) and significance calculated using a 2 sample Poisson rate test
