Valuable Tool Identified for Assessing Psoriatic Arthritis Activity

A measuring tool typically used to assess the activity of rheumatoid arthritis (RA) has proven to be valuable for analyzing disease activity in psoriatic arthritis (PsA) as well.

The Rheumatoid Arthritis Disease Activity Index-5 (RADAI-5) assessment questionnaire was modified into the Stockerau Activity Score for Psoriatic Arthritis (SASPA) to evaluate joint impairment caused by the disease. Lead author Burkhard F. Leeb, MD, PhD, and his Austrian team distributed the questionnaire to 97 PsA patients made up of 49 males and 48 females with an average age of 49.78.

“Peripheral joint damage is significantly greater in RA than in PsA,” the study, documented in BMC Musculoskeletal Disorders, explained. “However, joint function and quality of life scores frequently indicate the same amount of impairment for both diseases, which may be due to the additional burden of skin disease in PsA.”

The questionnaire includes 6 questions and the patients answered using the 0 to 10 Likert scale:

• How active was your arthritis in the last 6 months?
• How active is your arthritis today with respect to joint tenderness and swelling?
• How severe is your arthritis pain today?
• How would you describe your general health today?
• Did you experience joint (hand) stiffness on awaking yesterday morning? If yes, how long was this stiffness?
• How active do you regard your skin disease? (would only be used if the patient has PsA)

Using a visual analog scale (VAS), the participants’ tender joint count (TJC) and swollen joint count (SJC), including dactylitis and enthesiopathy, were recorded as well.

Cronbach’s alpha was used to examine the accuracy of the questionnaire and proved to have internal consistency.

“Factorial analysis showed a mono-component structure (Eigenvalue 3.628) as well as an item loading between 0.558 (Question 6) and 0.892 (Question 3), indicating that every question contributed significantly to the aggregated results,” the study noted.

Although there are multiple activity measuring systems, there is not one in particular has been accepted widespread.As of now SASPA is only approved for RA, however, it showed promising results and has been used during clinical trials for PsA.

The findings may become a useful tool for physicians to make better treatment decisions for patients in the future.

“The SASPA questionnaire constitutes a fully patient-administered tool to monitor PsA activity,” the researchers concluded. “Its reliability, convergent validity, and sensitivity to change were demonstrated.”