Table 3. Risk factors for chikungunya virus-associated long-term polyarthralgia (n = 160).
| Pain duration | |||||||
|---|---|---|---|---|---|---|---|
| < 6 weeks (n = 90) | > 6 weeks (n = 70) | > 1 year (n = 42) | |||||
| n = 90 (100%) |
n = 70 (100%) |
OR [95%-CI] | n = 42 (100%) |
OR [95%-CI] | |||
| Risk factors | Univariate | Multivariate | Univariate | Multivariate | |||
| Age, yrs (IQR) |
50 (35–63) |
50 (37–56) |
49 (37–54) |
||||
| ≤ 40 | 25 (27.8) |
20 (4.3) |
- | 13 (31.0) |
- | ||
| > 40 | 65 (71.4) |
50 (24.3) |
1.0 [0.5–2.0] | 29 (69.0) |
1.1 [0.5–2.5] | ||
| Female gender | 52 (57.8) |
57 (81.4) |
3.2 [1.6–6.9] | 3.4 [1.6–8.0] | 36 (85.7) |
4.4 [1.8–12.5] | 5.9 [2.1–19.6] |
| Obesity | 6 (6.6) |
17 (24.3) |
4.5 [1.8–13.1] | 4.8 [1.8–14.7] | 10 (23.8) |
4.4 [1.5–13.8] | |
| Diabetes | 8 (8.8) |
4 (5.7) |
0.6 [0.2–2.1] | 2 (4.8) |
0.5 [0.1–2.2] | ||
| Rheumatol. condition | 3 (3.3) |
1 (1.4) |
0.4 [0.0–3.4] | 1 (2.4) |
0.7 [0.0–5.7] | ||
| Osteoporosis | 5 (5.5) |
0 | 0 | ||||
| Osteo-arthritis | 5 (5.5) |
4 (5.7) |
1.0 [0.3–4.1] | 3 (7.1) |
1.3 [0.3–5.7] | ||
| Sleep * | 25 (27.4) |
32 (45.7) |
2.2 [1.1–4.3] | 22 (52.4) |
2.9 [1.3–6.2] | ||
| Concentration * | 12 (13.2) |
26 (37.1) |
3.8 [1.8–8.6] | 4.7 [2.1–11.1] | 17 (40.5) |
4.4 [1.9–10.7] | |
| Redness | 17 (18.7) |
17 (24.3) |
1.4 [0.7–3.0] | 9 (21.4) |
1.2 [0.5–2.9] | ||
| Edema | 26 (28.9) |
36 (51.4) |
2.5 [1.3–4.9] | 25 (59.5) |
3.6 [1.7–7.9] | ||
| Stiffness | 58 (64.4) |
56 (80.0) |
2.2 [1.1–4.6] | 34 (81.0) |
2.3 [1.0–5.9] | ||
| Finger | 39 (43.3) |
44 (62.9) |
2.2 [1.2–4.1] | 31 (73.8) |
3.7 [1.7–8.5] | ||
| High ACR-score | 37 (41.1) |
45 (64.3) |
2.6 [1.4–5.0] | 2.9 [1.4–6.1] | 33 (78.6) |
5.3 [2.3–12.9] | 7.4 [2.7–23.3] |
| RT-PCR positive > 7 DPSO¶ |
4/20 (20.0) |
11/22 (50.0) |
4.0 [1.1–17.6] | 8/13 (61.5) |
6.4 [1.4–34.1] | ||
To control for confounding we performed Stepwise Logistic Regression, using backward elimination for any variable (including age) whose univariate test p-value < 0.10.
* Sleep and concentration disorder were identified as risk factors for arthralgia; however, in our study it was not possible to distinguish whether these were predictors or consequences.
DPSO denotes days post symptom onset.
¶ The Odds Ratios were calculated for 42 of 160 patients, whose sera were collected after 7 DPSO.