Table 2.
Associations between weight change from baseline and age 18 with RA
| Categories of time-updated weight change from 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 | 48/197 984 | 51/450 712 | 193/974 788 | 131/453 192 | 69/201 566 |
| RR (95% CI) Unadjusted | 2.10 (1.42, 3.12) | Ref | 1.71 (1.26, 2.33) | 2.46 (1.78, 3.40) | 2.88 (2.01, 4.14) |
| RR (95% CI) MSMa | 2.05 (1.28, 3.28) | Ref | 1.98 (1.38, 2.85) | 3.28 (2.20, 4.89) | 3.81 (2.39, 6.07) |
| Seropositive RA | |||||
| # of cases/person-years | 35/197 778 | 38/450 190 | 116/973 710 | 91/452 792 | 48/201 404 |
| RR (95% CI) Unadjusted | 2.06 (1.30, 3.26) | Ref | 1.38 (0.96, 1.99) | 2.29 (1.57, 3.35) | 2.69 (1.76, 4.12) |
| RR (95% CI) MSMa | 2.08 (1.21, 3.58) | Ref | 1.66 (1.08, 2.56) | 3.17 (1.98, 5.08) | 3.54 (2.04, 6.12) |
| Seronegative RA | |||||
| # of cases/person-years | 13/197 425 | 13/449 678 | 77/972 561 | 40/452 145 | 21/201 117 |
| RR (95% CI) Unadjusted | 2.24 (1.04, 4.82) | Ref | 2.68 (1.49, 4.82) | 2.95 (1.58, 5.51) | 3.44 (1.72, 6.87) |
| RR (95% CI) MSMa | 1.95 (0.76, 5.05) | Ref | 2.94 (1.49, 5.80) | 3.62 (1.71, 7.67) | 4.64 (1.92, 11.21) |
| 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 | 32/174 225 | 27/210 913 | 111/801 307 | 168/676 627 | 201/698 871 |
| RR (95% CI) Unadjusted | 1.43 (0.85, 2.38) | Reference | 1.08 (0.71, 1.65) | 1.94 (1.29, 2.91) | 2.23 (1.49, 3.33) |
| RR (95% CI) MSMa | 1.23 (0.72, 2.11) | Reference | 1.16 (0.74, 1.81) | 2.12 (1.37, 3.27) | 2.31 (1.50, 3.56) |
| Seropositive RA | |||||
| # of cases/person-years | 26/174 065 | 19/210 693 | 68/800 407 | 104/675 826 | 140/698 123 |
| RR (95% CI) Unadjusted | 1.65 (0.91, 2.98) | Reference | 0.94 (0.57, 1.57) | 1.70 (1.05, 2.78) | 2.21 (1.37, 3.56) |
| RR (95% CI) MSMa | 1.30 (0.70, 2.42) | Reference | 0.95 (0.56, 1.62) | 1.84 (1.09, 3.10) | 2.16 (1.29, 3.61) |
| Seronegative RA | |||||
| # of cases/person-years | 6/173 867 | 8/210 494 | 43/799 612 | 64/674 884 | 61/696 922 |
| RR (95% CI) Unadjusted | 0.90 (0.31, 2.60) | Reference | 1.41 (0.66, 3.01) | 2.49 (1.19, 5.20) | 2.29 (1.09, 4.78) |
| RR (95% CI) MSMa | 1.03 (0.34, 3.06) | Reference | 1.77 (0.79, 3.99) | 2.93 (1.34, 6.40) | 2.77 (1.26, 6.08) |
Study conducted in the Nurses’ Health Study II between 1989 and 2015.
Adjusted for previous questionnaire cycle weight change, baseline weight in 1989, 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.