FIGURE 1.

HRs for incident seropositive rheumatoid arthritis according to sugar-sweetened soda consumption in the Nurses’ Health Study (1980–2008) stratified by age at diagnosis of rheumatoid arthritis. HRs were calculated by using time-varying Cox proportional hazards models. Results were adjusted for age, census tract median family income (quartiles), cigarette smoking status (never; past; current, 1–14 cigarettes/d; or current, ≥15 cigarettes/d), alcohol consumption (<5.0, 5.0–15.0, or ≥15 g/d), age at menarche (<12, 12, or >12 y), parity and breastfeeding (nulliparous, parous/no breastfeeding, parous/1–12 mo breastfeeding, or parous/>12 mo breastfeeding), hormone use (premenopausal, postmenopausal with never use, current use, or past use), physical activity (0–2.9, 3–8.9, 9–17.9, 18–26.9, or ≥27 metabolic equivalent task hours/wk), BMI (in kg/m²; <20, 20–22.9, 23–24.9, 25–29.9, or ≥30), multivitamin use, Alternate Healthy Eating Index (quintiles), diabetes history, and total energy (kcal, quintiles). Reference category, <1 serving/mo.