Table 3.
Factors associated with persistent inflammatory arthritis among people classified as having CPPD disease
| Persistent inflammatory arthritis | Odds ratio (95% CI) | ||||
|---|---|---|---|---|---|
| No (n = 460) | Yes (n = 158) | Unadjusted | Model 1 a | Model 2 b | |
| Current age, mean (SD) | 74.2 (12.5) | 73.6 (9.9) | 0.99 (0.98–1.01) | 0.99 (0.98–1.01) | 0.98 (0.97–1.00) |
| Sex, n (%) | |||||
| Female (ref) | 256 (55.6) | 90 (57.0) | 1 | 1 | 1 |
| Male | 204 (44.3) | 68 (43.0) | 0.95 (0.66–1.36) | 0.94 (0.65–1.35) | 1.00 (0.67–1.50) |
| Symptom duration, n (%) | |||||
| ≤2 y (ref) | 181 (39.3) | 53 (33.5) | 1 | 1 | 1 |
| >2 y | 279 (60.6) | 105 (66.5) | 1.28 (0.88–1.88) | 1.28 (0.88–1.88) | 1.37 (0.89–2.08) |
| Acute arthritis | |||||
| Knee, n (%) | |||||
| No (ref) | 139 (30.2) | 64 (40.5) | 1 | 1 | 1 |
| Yes | 321 (69.8) | 94 (59.5) | 0.64 (0.44–0.93) | 0.63 (0.43–0.92) | 1.04 (0.66–1.63) |
| Wrist, n (%) | |||||
| No (ref) | 260 (56.5) | 43 (27.2) | 1 | 1 | 1 |
| Yes | 200 (43.5) | 115 (72.8) | 3.48 (2.34–5.17) | 3.51 (2.36–5.22) | 2.92 (1.81–4.73) |
| No. of acute inflammatory arthritis episodes, n (%) | |||||
| 0 (ref) | 12 (2.6) | 4 (2.5) | 1 | 1 | 1 |
| 1 | 199 (43.3) | 71 (44.9) | 1.07 (0.33–3.43) | 1.08 (0.34–3.48) | 0.70 (0.19–2.54) |
| >1 | 249 (54.1) | 83 (52.5) | 1.00 (0.31–3.19) | 1.01 (0.32–83.23) | 0.48 (0.13–1.81) |
| CDS, n (%) | |||||
| No (ref) | 432 (93.9) | 141 (89.2) | 1 | 1 | 1 |
| Yes | 28 (6.1) | 17 (10.8) | 1.86 (0.99–3.50) | 1.89 (1.00–3.57) | 1.97 (0.98–3.97) |
| Metabolic or familial predisposition, n (%) | |||||
| No (ref) | 325 (70.6) | 125 (79.1) | 1 | 1 | 1 |
| Yes | 135 (29.3) | 33 (20.9) | 0.64 (0.41–0.98) | 0.63 (0.41–0.97) | 0.60 (0.37–0.96) |
| 2/3 MCPJ OA, n (%) | |||||
| No (ref) | 363 (78.9) | 90 (57.0) | 1 | 1 | 1 |
| Yes | 97 (21.1) | 68 (43.0) | 2.83 (1.92–4.16) | 2.93 (1.98–4.33) | 1.87 (1.17–2.97) |
| Any STTJ OA, n (%) | |||||
| No (ref) | 370 (80.4) | 90 (57.0) | 1 | 1 | 1 |
| Yes | 90 (19.6) | 68 (43.0) | 3.11 (2.10–4.59) | 3.27 (2.20–4.87) | 1.83 (1.15–2.91) |
| Any wrist OA, n (%) | |||||
| No (ref) | 340 (73.9) | 89 (56.3) | 1 | 1 | 1 |
| Yes | 120 (26.1) | 69 (43.7) | 2.20 (1.51–3.20) | 2.29 (1.56–3.37) | 1.21 (0.75–1.94) |
| Any SLAC wrist, n (%) | |||||
| No (ref) | 432 (93.9) | 140 (88.6) | 1 | 1 | 1 |
| Yes | 28 (6.1) | 18 (11.4) | 1.98 (1.06–3.70) | 2.02 (1.08–3.78) | 1.07 (0.53–2.14) |
| Number of joints with CC, median (IQR) | 2 (1–4) | 2 (2–4) | 1.05 (0.93–1.19) | 1.05 (0.93–1.20) | 0.91 (0.79–1.05) |
Statistically significant associations are shown in bold typeface. CC, chondrocalcinosis; CDS, crowned dens syndrome; CI, confidence interval; CPPD, calcium pyrophosphate deposition; IQR, interquartile range; MCPJ, meta‐carpo‐phalangeal joint; OA, osteoarthritis; ref, reference; SLAC, scapho‐lunate advanced collapse; STTJ, scapho‐trapezo‐trapezoid joint.
Adjustment for age and sex.
Adjustment for all covariates: current age (years), gender, symptom duration (>2 or ≤2 years), acute knee arthritis (yes/no), acute wrist arthritis (yes/no), only one or recurrent acute episodes, CDS (yes/no), metabolic or familial predisposition (yes/no), MCPJ OA (yes/no), STTJ OA (yes/no), wrist OA (yes/no), SLAC wrist (yes/no), and number of joints with CC.