Table 3.
Associations between weight change from baseline and age 18 with rheumatoid arthritis (2-year lag)
| Categories of time-updated weight change since baseline |
|||||
|---|---|---|---|---|---|
| Loss (>2 kg) | Stable (−2 to <2 kg) | Gain (2 to <10 kg) | Gain (10 to <20 kg) | Gain (≥20 kg) | |
| All RA | |||||
| # of cases/person-years | 45/177 960 | 66/411 716 | 188/891 110 | 119/396 235 | 52/170 106 |
| RR (95% CI) Unadjusted | 1.58 (1.08, 2.31) | Ref | 1.32 (1.00, 1.75) | 1.86 (1.38, 2.52) | 1.88 (1.31, 2.71) |
| RR (95% CI) by MSMa | 1.25 (0.77, 2.02) | Ref | 1.57 (1.12, 2.22) | 2.11 (1.45, 3.07) | 2.24 (1.37, 3.65) |
| Seropositive RA | |||||
| # of cases/person-years | 28/177 779 | 40/411 264 | 123/890 186 | 85/395 914 | 36/169 981 |
| RR (95% CI) Unadjusted | 1.62 (1.00, 2.63) | Ref | 1.43 (1.00, 2.04) | 2.20 (1.51, 3.20) | 2.15 (1.37, 3.38) |
| RR (95% CI) by MSMa | 1.18 (0.65, 2.16) | Ref | 1.54 (1.00, 2.37) | 2.19 (1.36, 3.51) | 2.28 (1.28, 4.06) |
| Seronegative RA | |||||
| # of cases/person-years | 17/177 482 | 26/410 809 | 65/889 135 | 34/395 381 | 16/169 768 |
| RR (95% CI) Unadjusted | 1.52 (0.82, 2.79) | Ref | 1.16 (0.74, 1.83) | 1.35 (0.81, 2.25) | 1.47 (0.79, 2.74) |
| RR (95% CI) by MSMa | 1.38 (0.63, 3.05) | Ref | 1.65 (0.95, 2.86) | 1.94 (1.07, 3.53) | 2.15 (0.86, 5.39) |
| Categories of time-updated weight change since age 18 |
|||||
|---|---|---|---|---|---|
| Loss (>2 kg) | Stable (−2 to <2 kg) | Gain (2 to <10 kg) | Gain (10 to <20 kg) | Gain (≥20 kg) | |
| All RA | |||||
| # of cases/person-years | 26/165 325 | 31/200 139 | 112/757 758 | 167/618 377 | 181/620 722 |
| RR (95% CI) Unadjusted | 1.02 (0.60, 1.71) | Ref | 0.95 (0.64, 1.42) | 1.73 (1.18, 2.54) | 1.86 (1.27, 2.72) |
| RR (95% CI) by MSMa | 0.80 (0.45, 1.42) | Ref | 0.96 (0.62, 1.50) | 1.81 (1.17, 2.78) | 1.72 (1.12, 2.65) |
| Seropositive RA | |||||
| # of cases/person-years | 19/165 176 | 21/199 929 | 68/756 943 | 112/617 692 | 123/620 086 |
| RR (95% CI) Unadjusted | 1.10 (0.59, 2.04) | Ref | 0.85 (0.52, 1.39) | 1.71 (1.07, 2.73) | 1.86 (1.17, 2.96) |
| RR (95% CI) by MSMa | 0.77 (0.39, 1.53) | Ref | 0.76 (0.44, 1.30) | 1.65 (0.98, 2.79) | 1.53 (0.90, 2.59) |
| Seronegative RA | |||||
| No. of cases/person-yrs | 7/164 997 | 10/199 758 | 44/756 177 | 55/616 809 | 58/619 081 |
| RR (95% CI) Unadjusted | 0.85 (0.32, 2.23) | Ref | 1.16 (0.58, 2.31) | 1.77 (0.90, 3.47) | 1.85 (0.94, 3.61) |
| RR (95% CI) MSMa | 0.89 (0.32, 2.46) | Ref | 1.62 (0.77, 3.41) | 2.29 (1.11, 4.74) | 2.32 (1.13, 4.79) |
Study conducted in the Nurses’ Health Study II between 1989 and 2015.
Adjusted for previous questionnaire cycle weight change, baseline weight, age (years, continuous), smoking (never smoker, <20 pack years of smoking, 20+ pack years of smoking), parity and breastfeeding status (nulliparous, parous/no breastfeeding, parous/1–12 months breastfeeding, parous/>12 months breastfeeding), menopausal status and hormone use (pre-menopausal, post-menopausal with never use, current use and past use), census tract median family income (quartiles), physical activity (0–2.9, 3–8.9, 9–17.9, ≥18 METs/week), Alternative Healthy Eating Index (quartiles).
kg, kilograms; MSM, marginal structural model.