| Characteristic | Gout cases (n = 164) |
| Age (years), mean (SD) | 63.4 (11.2) |
| Male gender, n (%) | 133 (81) |
| BMI (kg/m2), mean (SD) | 27.8 (4.0) |
| Age at first attack (years), mean (SD) | 50.5 (13.7) |
| Disease duration (years), median (range) | 10 (0–50) |
| Tophus, n (%) | |
| Total | 10 (6) |
| Definite | 5 (3) |
| Possible | 5 (3) |
| Fulfilled ARA preliminary criteria for primary gout (%) | 150 (92%) |
| Serum urate (μmol/l), mean (SD)* | 399 (107) |
| Serum creatinine (μmol/l), median (range)† | 94 (63 to 180) |
| GFR (ml/min), median (range) | 78 (19 to 170) |
| GFR (<60 ml/min), n (%) | 39 (24%) |
| Medication use, n (%) | |
| Taken diuretics prior to first attack | 25 (15) |
| Low-dose aspirin | 51 (31) |
| Allopurinol | 44 (30) |
| Uricosuric agents | 0 |
| Possible secondary gout, n (%)‡ | 50 (30) |
ARA, American Rheumatism Association; BMI, body mass index; GFR, glomerular filtration rate.
*Normal range 100–400 μmol/l; †normal range 60–120 μmol/l; ‡GFR<60 ml/min or taking diuretics prior to first attack.