Table 1

 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 = 269Work disabled, n = 31Employed, n = 238Total, n = 364Work disabled, n = 86Employed, 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 education12 (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 work130 (48.3)10 (32.3)120 (50.4)130 (35.7)16 (18.6)114 (41.0)0.001
Disease characteristics
    Positive rheumatoid factor177 (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