OBJECTIVES: To assess the association of disease flares with clinical outcomes, health status, and work productivity loss among patients with RA. METHODS: Data were collected from individuals aged ≥18 and reporting an RA diagnosis through a cross-sectional, self-administered, Internet-based questionnaire.  Frequency of disease flares were categorized as: no flares (reference group), <1 per month, 1 per month, 2-3 per month, 1 per week, 2-3 per week, 4-6 per week, and daily. Clinical outcomes included the Health Assessment Questionnaire (HAQ) and severity of morning stiffness, fatigue, and pain, measured as 1=none experienced to 10=severe. Health status was assessed using the SF-36, and work productivity loss (employed individuals only) and activity impairment were assessed using the Work Productivity and Activity Impairment questionnaire.  Patient demographics and comorbidities were adjusted using linear regression and negative binomial regression as appropriate.  RESULTS: Of 2,135 patients, 47.4% (n=1,011) experienced a disease flare in the past six months and 52.7% (n=1,124) experienced no flares.  Greater frequency of flares was significantly associated with greater functional disability; greater severity of morning stiffness, fatigue, and pain; poorer physical and mental health status; greater lost work productivity and activity impairment.  Specifically, daily flares were associated with greater functional disability (HAQ: regression coefficient b=0.56, p<0.001); greater severity of morning stiffness (b=2.27, p<0.001), fatigue (b=2.20, p<0.001), and pain (b=2.51, p<0.001); poorer health status (SF-36 physical component summary: b=-8.76, p<0.001 and mental component summary: b=-7.48, p=0.005); and greater work impairment (event ratio=2.20, p<0.001) and activity impairment (event ratio=1.68, p<0.001). CONCLUSIONS: RA disease flares are associated with worse clinical outcomes, poorer health status, and greater lost work productivity.  However, due to the cross-sectional nature of the study, the direction of these associations cannot be determined.  Treatments that minimize disease flares may provide additional benefit in clinical outcomes, health status, and work productivity.