Psoriasis Plus Joint Pain Doesn't Always Equal PsA : Only 55% of a small series of patients with psoriasis and musculoskeletal pain had psoriatic arthritis.

STOCKHOLM — It may be wrong to assume that patients with psoriasis and joint pain have psoriatic arthritis, according to data presented at an international conference on psoriasis and psoriatic arthritis by Dr. Elinor Mody.

“Joint pain in patients with psoriasis does not necessarily equal psoriatic arthritis,” said Dr. Mody, a rheumatologist at Brigham and Women's Hospital in Boston.

She and her colleagues assessed 71 consecutive patients with psoriasis and musculoskeletal pain who presented to a combined dermatology/rheumatology clinic. Average patient age was 53 years and 52% of the studied patients were women. All were evaluated by both a dermatologist and a rheumatologist.

Based on the Moll and Wright criteria (Semin. Arthritis Rheum. 1973;3:55–78), 41% were diagnosed with psoriatic arthritis alone. Based on the American College of Rheumatology criteria for osteoarthritis of the hand, and knee and hip radiographs, 27% were diagnosed with osteoarthritis alone. In addition, 3% were diagnosed with gout and 14% had no specific diagnosis. Fourteen percent were diagnosed with both psoriatic arthritis and osteoarthritis.

“These findings highlight that patients with psoriasis and musculoskeletal pain can have a variety of conditions causing this pain and cannot be assumed to have psoriatic arthritis,” said Dr. Mody.

Differentiating between psoriatic arthritis and other arthropathies can be difficult but is “extremely important as psoriatic arthritis is deforming and crippling and requires aggressive early therapy,” said Dr. Mody. “Better methods are needed for screening for psoriatic arthritis in a patient with psoriasis.”

To address this need, Dr. Mody and her colleagues developed the psoriatic arthritis screening and evaluation (PASE) questionnaire intended for physicians to use to screen patients with psoriasis for evidence of psoriatic arthritis. The self-administered questionnaire includes 15 five-choice questions, separated into symptom and function subscales.

Forty-five consecutive patients (24 women) answered the questionnaire prior to systemic therapy. A rheumatologist and a dermatologist working together diagnosed 27 patients with psoriasis alone and 18 with psoriatic arthritis.

Patients with psoriatic arthritis had a median total PASE score of 53, compared with a median score of 40 for patients with psoriasis alone—a difference that was statistically significant. With a total score cutoff of 47—a score of 47 or greater indicates psoriatic arthritis—sensitivity of PASE was 83% and specificity was 70%.

“These patients need to be reevaluated periodically,” said Dr. Mody. She and here colleagues recommend repeating the PASE every 6–12 months in patients with psoriasis and joint pain.

The median function score for patients with psoriatic arthritis was 27, compared with 19 for those with psoriasis alone. The median symptom score for patients with psoriatic arthritis was 24, compared with 21 for those with psoriasis alone.

The researchers are planning to assess retest reliability of the PASE, as well as to investigate changes in PASE scores following the initiation of therapy.

STOCKHOLM — It may be wrong to assume that patients with psoriasis and joint pain have psoriatic arthritis, according to data presented at an international conference on psoriasis and psoriatic arthritis by Dr. Elinor Mody.

“Joint pain in patients with psoriasis does not necessarily equal psoriatic arthritis,” said Dr. Mody, a rheumatologist at Brigham and Women's Hospital in Boston.

She and her colleagues assessed 71 consecutive patients with psoriasis and musculoskeletal pain who presented to a combined dermatology/rheumatology clinic. Average patient age was 53 years and 52% of the studied patients were women. All were evaluated by both a dermatologist and a rheumatologist.

Based on the Moll and Wright criteria (Semin. Arthritis Rheum. 1973;3:55–78), 41% were diagnosed with psoriatic arthritis alone. Based on the American College of Rheumatology criteria for osteoarthritis of the hand, and knee and hip radiographs, 27% were diagnosed with osteoarthritis alone. In addition, 3% were diagnosed with gout and 14% had no specific diagnosis. Fourteen percent were diagnosed with both psoriatic arthritis and osteoarthritis.

“These findings highlight that patients with psoriasis and musculoskeletal pain can have a variety of conditions causing this pain and cannot be assumed to have psoriatic arthritis,” said Dr. Mody.

Differentiating between psoriatic arthritis and other arthropathies can be difficult but is “extremely important as psoriatic arthritis is deforming and crippling and requires aggressive early therapy,” said Dr. Mody. “Better methods are needed for screening for psoriatic arthritis in a patient with psoriasis.”

To address this need, Dr. Mody and her colleagues developed the psoriatic arthritis screening and evaluation (PASE) questionnaire intended for physicians to use to screen patients with psoriasis for evidence of psoriatic arthritis. The self-administered questionnaire includes 15 five-choice questions, separated into symptom and function subscales.

Forty-five consecutive patients (24 women) answered the questionnaire prior to systemic therapy. A rheumatologist and a dermatologist working together diagnosed 27 patients with psoriasis alone and 18 with psoriatic arthritis.

Patients with psoriatic arthritis had a median total PASE score of 53, compared with a median score of 40 for patients with psoriasis alone—a difference that was statistically significant. With a total score cutoff of 47—a score of 47 or greater indicates psoriatic arthritis—sensitivity of PASE was 83% and specificity was 70%.

“These patients need to be reevaluated periodically,” said Dr. Mody. She and here colleagues recommend repeating the PASE every 6–12 months in patients with psoriasis and joint pain.

The median function score for patients with psoriatic arthritis was 27, compared with 19 for those with psoriasis alone. The median symptom score for patients with psoriatic arthritis was 24, compared with 21 for those with psoriasis alone.

The researchers are planning to assess retest reliability of the PASE, as well as to investigate changes in PASE scores following the initiation of therapy.

STOCKHOLM — It may be wrong to assume that patients with psoriasis and joint pain have psoriatic arthritis, according to data presented at an international conference on psoriasis and psoriatic arthritis by Dr. Elinor Mody.

“Joint pain in patients with psoriasis does not necessarily equal psoriatic arthritis,” said Dr. Mody, a rheumatologist at Brigham and Women's Hospital in Boston.

She and her colleagues assessed 71 consecutive patients with psoriasis and musculoskeletal pain who presented to a combined dermatology/rheumatology clinic. Average patient age was 53 years and 52% of the studied patients were women. All were evaluated by both a dermatologist and a rheumatologist.

Based on the Moll and Wright criteria (Semin. Arthritis Rheum. 1973;3:55–78), 41% were diagnosed with psoriatic arthritis alone. Based on the American College of Rheumatology criteria for osteoarthritis of the hand, and knee and hip radiographs, 27% were diagnosed with osteoarthritis alone. In addition, 3% were diagnosed with gout and 14% had no specific diagnosis. Fourteen percent were diagnosed with both psoriatic arthritis and osteoarthritis.

“These findings highlight that patients with psoriasis and musculoskeletal pain can have a variety of conditions causing this pain and cannot be assumed to have psoriatic arthritis,” said Dr. Mody.

Differentiating between psoriatic arthritis and other arthropathies can be difficult but is “extremely important as psoriatic arthritis is deforming and crippling and requires aggressive early therapy,” said Dr. Mody. “Better methods are needed for screening for psoriatic arthritis in a patient with psoriasis.”

To address this need, Dr. Mody and her colleagues developed the psoriatic arthritis screening and evaluation (PASE) questionnaire intended for physicians to use to screen patients with psoriasis for evidence of psoriatic arthritis. The self-administered questionnaire includes 15 five-choice questions, separated into symptom and function subscales.

Forty-five consecutive patients (24 women) answered the questionnaire prior to systemic therapy. A rheumatologist and a dermatologist working together diagnosed 27 patients with psoriasis alone and 18 with psoriatic arthritis.

Patients with psoriatic arthritis had a median total PASE score of 53, compared with a median score of 40 for patients with psoriasis alone—a difference that was statistically significant. With a total score cutoff of 47—a score of 47 or greater indicates psoriatic arthritis—sensitivity of PASE was 83% and specificity was 70%.

“These patients need to be reevaluated periodically,” said Dr. Mody. She and here colleagues recommend repeating the PASE every 6–12 months in patients with psoriasis and joint pain.

The median function score for patients with psoriatic arthritis was 27, compared with 19 for those with psoriasis alone. The median symptom score for patients with psoriatic arthritis was 24, compared with 21 for those with psoriasis alone.

The researchers are planning to assess retest reliability of the PASE, as well as to investigate changes in PASE scores following the initiation of therapy.