Comparison of characteristics of patients who were working at the time of their first symptoms of rheumatoid arthritis in Nashville, Tennessee, USA and Jyväskylä, Finland
| Nashville* | Jyväskylä† | p Value‡ | |||||
|---|---|---|---|---|---|---|---|
| Total, n = 269 | Work disabled, n = 31 | Employed, n = 238 | Total, n = 364 | Work disabled, n = 86 | Employed, n = 278 | ||
| DMARD, disease-modifying antirheumatic drug. | |||||||
| *Missing data from Nashville: time to first DMARD (n = 3), modified health assessment questionnaire at baseline (n = 5), pain on Visual Analogue Scale at baseline (n = 4), patient global assessment at baseline (n = 5), pain on Visual Analogue Scale at last observation (n = 31), fatigue at last observation (n = 32), patient global assessment at last observation (n = 29), morning stiffness at last observation (n = 45), modified health assessment questionnaire (n = 45), extra-articular disease (n = 2). | |||||||
| †Missing data from Jyväskylä: time to first DMARD (n = 11), modified health assessment questionnaire at diagnosis (n = 35), pain on Visual Analogue Scale at diagnosis (n = 43), patient global assessment at diagnosis (n = 43), fatigue at last observation (n = 19), patient global assessment at last observation (n = 16), morning stiffness (n = 59), modified health assessment questionnaire (n = 21). | |||||||
| ‡p Value for comparison of Nashville (total) with Jyväskylä (total). | |||||||
| §Values are median (interquartile range). | |||||||
| ¶ Values are frequency (%). | |||||||
| **Wilcoxon rank sum test for continuous and χ2 for categorical variables. | |||||||
| Demographic variables | |||||||
| Age at first symptom§ | 46.1 (38.5–53.3) | 44.2 (34.5–48.6) | 46.3 (38.7–53.7) | 47.1 (36.6–53.0) | 51.9 (47.7–56.2) | 45.0 (33.9–51.6) | 0.99 |
| Female¶ | 195 (72.5) | 22 (71.0) | 173 (72.7) | 258 (70.9) | 64 (74.4) | 194 (69.8) | 0.66 |
| Years of education | 12 (12–15) | 12 (12–14) | 12 (12–16) | 11 (9–14) | 10 (9–11) | 12 (9–15) | <0.001 |
| Caucasians¶ | 240 (89.2) | 23 (74.2) | 215 (91.1) | 357 (100) | 86 (100) | 271 (100) | <0.001 |
| Sedentary work | 130 (48.3) | 10 (32.3) | 120 (50.4) | 130 (35.7) | 16 (18.6) | 114 (41.0) | 0.001 |
| Disease characteristics | |||||||
| Positive rheumatoid factor | 177 (68.6) | 24 (85.7) | 153 (66.5) | 175 (48.3) | 48 (56.5) | 127 (45.9) | <0.001 |
| Disease duration (months) | 17 (9–29) | 22 (6–31) | 17 (9–29) | 6 (3–13) | 6 (3–12) | 7 (3–13) | <0.001 |
| Time to first DMARD (months)§ | 6.7 (3.3–14.1) | 3.9 (2.0–10.8) | 7.0 (3.9–15.2) | 6.1 (3.1–12.2) | 6.1 (3.1–12.2) | 6.3 (3.1–12.2) | 0.94 |
| Methotrexate ever¶ | 241 (89.6) | 28 (90.3) | 213 (89.5) | 259 (71.2) | 69 (80.2) | 190 (68.4) | <0.001 |
| Biological ever¶ | 31 (11.5) | 7 (22.6) | 24 (10.1) | 24 (6.6) | 10 (11.6) | 14 (5.0) | 0.03 |
| Prednisone ever¶ | 227 (84.4) | 30 (96.8) | 197 (82.8) | 209 (57.4) | 61 (70.9) | 148 (53.2) | <0.001 |
| Extra-articular disease ever¶ | 13 (4.9) | 3 (9.7) | 10 (4.2) | 11 (3.0) | 4 (4.7) | 7 (2.5) | 0.23 |
| Patient questionnaire measures | |||||||
| Pain on the Visual Analogue Scale at baseline (0–100)§ | 41.0 (19.0–63.0) | 70.0 (45.0–80.0) | 37.5 (16.0–62.0) | 40.0 (23.0–61.0) | 51.5 (36.0–71.0) | 36.0 (18.0–53.5) | 0.84 |
| Patient global assessment at baseline(0–100)§ | 40.5 (17.5–53.5) | 56.0 (45.0–78.0) | 35.0 (15.0–51.0) | 34.0 (20.0–52.0) | 45.0 (33.0–61.0) | 32.0 (16.0–49.0) | 0.42 |
| Modified health assessment questionnaire at baseline (0–3)§ | 0.4 (0.0–0.9) | 0.9 (0.6–1.4) | 0.3 (0.0–0.8) | 0.4 (0.1–0.6) | 0.6 (0.3–0.9) | 0.3 (0.0–0.6) | 0.35 |
| Pain on the Visual Analogue Scale at last observation (0–100)§ | 38.0 (16.0–63.0) | 48.0 (36.0–69.0) | 36.0 (15.0–62.0) | 21.0 (6.0–41.0) | 35.0 (20.0–51.0) | 15.0 (4.0–35.0) | <0.001 |
| Fatigue at last observation (0–100)§ | 46.0 (17.0–70.0) | 65.0 (35.0–80.0) | 43.0 (16.0–66.0) | 24.0 (7.0–48.0) | 40.0 (21.5–59.5) | 18.0 (6.0–45.0) | <0.001 |
| Patient global assessment at last observation (0–100)§ | 36.0 (11.0–56.0) | 53.0 (30.0–71.0) | 34.0 (10.0–51.0) | 25.5 (11.0–46.0) | 38.5 (25.0–54.0) | 22.0 (8.0–40.0) | 0.002 |
| Morning stiffness at last observation(0–301)§ | 30.0 (5.0–120.0) | 60.0 (22.5–120.0) | 30.0 (3.0–120.0) | 30.0 (0.0–60.0) | 60.0 (30.0–120.0) | 15.0 (0.0–60.0) | 0.004 |
| Modified health assessment questionnaire at last observation (0–3)§ | 0.4 (0.0–0.9) | 0.9 (0.5–1.3) | 0.3 (0.0–0.9) | 0.1 (0.0–0.4) | 0.4 (0.1–0.6) | 0.0 (0.0–0.3) | <0.001 |
| Follow-up (months)§ | 38.9 (19.3–52.7) | 4.4 (1.0–12.7) | 40.7 (25.9–56.6) | 48.4 (23.7–74.5) | 17.5 (6.5–53.3) | 58.1 (31.6–77.3) | <0.001 |