Table 2

 Unadjusted HRs (95% CI) for work disability in patients with early rheumatoid arthritis by cohort (Nashville, Tennessee USA, and Jyväskylä, Finland)

Demographic variablesNashville* (n = 269)Jyväskylä† (n = 364)
DMARD, disease-modifying antirheumatic drug; MHAQ, multidimensional health assessment questionnaire.
    Age (years)
        36–45 v ⩽350.3 (0.1 to 1.1)1.7 (0.6 to 4.8)
        46–55 v ⩽350.8 (0.3 to 1.9)6.2 (2.5 to 15.4)
        >55 v ⩽350.2 (0.1 to 1.1)19.4 (7.5 to 49.9)
    Male v female0.8 (0.3 to 2.1)0.8 (0.5 to 1.4)
    Years of education
        12 v <120.6 (0.2 to 1.7)0.5 (0.3 to 1.1)
        >12 v <120.3 (0.1 to 0.9)0.2 (0.1 to 0.4)
    Non-Caucasian v Caucasian3.6 (1.5 to 8.6)NA
    Non-sedentary/sedentary work2.0 (0.9 to 4.5)2.5 (1.4 to 4.3)
Disease and drugs characteristics
    Positive/negative rheumatoid factor2.2 (0.7 to 6.3)1.5 (0.9 to 2.3)
    Disease duration 5–8 months v ⩽ 4 months0.6 (0.2 to 2.1)1.1 (0.6 to 1.9)
        9–24 months v⩽4 months0.3 (1.0 to 0.9)0.8 (0.4 to 1.4)
        >24 months v ⩽4 months0.4 (0.1 to 1.2)0.3 (0.1 to 0.7)
    Ever/never methotrexate use1.2 (0.3 to 5.2)1.7 (1.0 to 2.9)
    Ever/never biological use2.1 (0.9 to 5.4)1.8 (0.9 to 3.5)
    Ever/never prednisone use5.1 (0.7 to 37.8)2.2 (1.4 to 3.7)
    Any/none extra-articular disease1.9 (0.5 to 8.1)1.3 (0.4 to 4.2)
Patient questionnaires
    Pain at first assessment
        21–40 v ⩽204.1 (0.4 to 39.7)22.9 (3.1 to 169.2)
        41–60 v ⩽2012.6 (1.6 to 99.5)16.2 (2.2 to 122.7)
        ⩾61 v ⩽2015.9 (2.1 to 121.9)36.4 (5.0 to 267.9)
    Patient global assessment at first assessment
        21–35 v ⩽204.8 (0.5 to 46.4)2.4 (1.0 to 5.7)
        36–50 v ⩽208.0 (1.0 to 66.2)4.0 (1.8 to 9.0)
        ⩾51 v ⩽2020.0 (2.6 to 150.8)4.2 (1.9 to 9.4)
    MHAQ at first assessment
        0.1–0.6 v 02.3 (0.5 to 11.0)1.3 (0.6 to 2.7)
        ⩾0.6 v 03.2 (0.7 to 14.3)1.5 (0.7 to3.2)
    Pain at last observation
        11–25 v ⩽101.1 (0.2 to 6.5)2.5 (1.2 to 5.3)
        26–50 v ⩽102.5 (0.5 to 11.8)3.9 (2.0 to 7.9)
        ⩾51 v ⩽102.4 (0.5 to 10.8)3.7 (1.8 to 7.7)
    Fatigue at last observation
        11–30 v ⩽101.0 (0.2 to 4.7)2.6 (1.2 to 5.5)
        31–60 v ⩽101.0 (0.2 to 4.0)3.3 (1.6 to 6.7)
        ⩾60 v ⩽102.0 (0.6 to 7.2)4.4 (2.0 to 9.6)
    Global at last observation
        11–30 v ⩽100.9 (0.2 to 3.9)4.5 (1.6 to 13.0)
        31–50 v ⩽101.0 (0.2 to 3.9)6.9 (2.4 to 19.8)
        ⩾51 v ⩽102.8 (0.9 to 8.7)6.8 (2.3 to 19.7)
    MHAQ at last observation
        0.1–0.6 v 01.0 (0.3 to 3.3)3.7 (2.1 to 6.8)
        ⩾0.6 v 02.4 (0.8 to 6.7)7.3 (3.6 to 14.7)
    Time to first DMARD (months)
        3.1–6.0 v ⩽30.5 (0.2 to 1.4)1.5 (0.7 to 2.9)
        6.1–12.0 v ⩽30.5 (0.2 to 1.3)1.1 (0.5 to 2.4)
        ⩾12.1 v ⩽30.2 (0.1 to 0.7)0.7 (0.3 to 1.4)