A Study to Learn About the Study Medicine (Called Tofacitinib) in People With Psoriatic Arthritis

The purpose of this study is to learn about the safety and effects of the study medicine for the potential treatment of Psoriatic Arthritis (PsA). Psoriatic Arthritis is a joint swelling disease that can also affect the skin, nails and eyes. The study medicine is called Tofacitinib. This study is seeking participants who: * Started taking tofacitinib alone or with other approved medicines (eg. methotrexate, leflunomide, sulfasalazine, apremilast) for PsA disease. We will only look at participants' who started tofacitinib after December 14, 2017. * Have a 6-month follow-up visit (with a 3-month window) This is an observational study. Participants receiving Tofacitinib will be included to assess how well tofacitinib works. We will look at participants' demographic information and therapy history. We will also monitor participants' disease progression before and 6 months after treatment. We will examine the experiences of people receiving the study medicine. This will help us determine if the study medicine is safe and effective.

Tofacitinib is an oral Janus kinase (JAK) inhibitor approved in 2017 by the US Food and Drug Administration (FDA) for the treatment of adult patients with active PsA who have had an inadequate response or intolerance to methotrexate or other disease modifying antirheumatic drugs (DMARDs). As of December 3, 2021, Tofacitinib is approved for use in patients who have had an inadequate response or intolerance to one or more TNF blockers. This is an observational retrospective cohort study that will be conducted using patients enrolled in the CorEvitas PsA/SpA Registry, initiating tofacitinib on or after December 14th, 2017. Patients receiving tofacitinib will be included to assess the effectiveness of tofacitinib overall and when stratified by key variables of interest. More specifically, the overall aim will be to describe baseline demographic, therapy history, and disease activity characteristics and assess change in disease activity measures six months after initiation of tofacitinib. There are two primary objectives for this study: 1. To describe the effectiveness of all tofacitinib initiators at 6 months in PsA patients 2. To describe the effectiveness of all tofacitinib initiators at 6 months stratified by monotherapy and combination therapy of PsA