Inclusion Criteria:

• All patients with PsA diagnosed after 2005.
  • Diagnosis defined as a clinical diagnosis by a rheumatologist.
• Ability to consent.

A multifaceted approach will be utilized for recruitment of PsA patients for the study:

• Recruitment letters will be sent to the PsA patients identified in the Rochester Epidemiology Project (REP) cohort.
• PsA patients seen in the Division of Rheumatology that are not in REP will also be actively recruited.
• New patients referred to our Division would also be eligible for recruitment.

Exclusion Criteria:

• Individuals who do not comprehend English (i.e., participants must be able to read and sign a consent form without the assistance of an interpreter.)
• Individuals who are unable to sign consent (e.g., mentally challenged, those declared legally incompetent).
• Individuals regarded as belonging to a vulnerable population (e.g., prisoners).
• Antibiotic exposure within two weeks of stool microbiome collection.
• Patients who have a history of malignancy, exception: documented history of cured non-metastatic squamous or basal cell skin carcinoma will be allowed.

Eligibility last updated 3/29/2023. Questions regarding updates should be directed to the study team contact.