Disease activity prior to and after 12 months of disease-modifying antirheumatic drug treatment. Disease activity scores and functional measures ( Disease Activity Score based on 28-joint count erythrocyte sedimentation rate (DAS28-ESR), ESR, Clinical Disease Activity Index (CDAI), and Health Assessment Questionnaire (HAQ)) are shown according to Porphyromonas gingivalis (Pg) antibody status at the time of study entry, prior to disease-modifying antirheumatic drug therapy and after 12 months of treatment. Data were available at the time of study entry for all 17 Pg-positive and all 33 Pg-negative patients. At the 12-month follow-up visits, data for DAS28-ESR, ESR and CDAI were available from 16 Pg-positive and 22 Pg-negative patients. For the HAQ, data were available from 12 Pg-positive and 22 Pg-negative patients. Median values and interquartile ranges are shown, and the shaded regions represent normal or negative values. Although disease activity measures declined in both groups during the 12-month period, patients with Pg antibodies tended to have higher values, primarily for ESR and DAS28-ESR.