Assessment of enthesitis in psoriatic arthritis

Philip Helliwell

University of Leeds

Assessment of enthesitis in psoriatic arthritis – why bother?

• Enthesis suggested as hallmark patho-anatomical feature

• Clinical and radiological enthesopathy one of distinguishing clinical features for spondyloarthropathy and psoriatic arthritis

• Active clinical involvement may reflect general disease activity

What instruments already exist?

• Mander enthesitis index (MEI)– Mander M, Simpson JM, McLellan A, Walker D, Goodacre JA, Dick WC. Studies with an enthesis index as a

method of clinical assessment in ankylosing spondylitis. Ann rheum Dis 1987; 46:197-202.

• MASES– Heuft-Dorenbosch L, Spoorenberg A, van Tubergen A, Landewe R, van der Tempel H, Mielants H et al.

Assessment of enthesitis in ankylosing spondylitis. Annals of the Rheumatic Diseases 2003; 62:127-132.

• SPARCC– Gladman DD, Cook RJ, Schentag C, Feletar M, Inman RI, Hitchon C et al. The clinical assessment of

patients with psoriatic arthritis: results of a reliability study of the spondyloarthritis research consortium of Canada. J Rheum 2004; 31(6):1126-1131.

• MAJOR– Braun J, Brandt J, Listing J, Zink A, Alten R, Golder W et al. Treatment of active ankylosing

spondylitis with infliximab: a randomised controlled multicentre trial. Lancet 359(9313):1187-93, 2002.

Mander (MEI) enthesitis index•Nuchal crests

•Manubriosternal joints

•Costochondral joints

•Greater tuberosity of humerus

•Lateral and medial epicondyles of humerus

•Iliac crests

•Ant sup iliac spines

•Greater trochanter of femur

•Medial and lateral condyles of femur

•Insertion of Achilles tendons

•Insertion of plantar fascia

•Cervical, thoracic and lumbar spinous processes

•Ischial tuberosities

•Post sup iliac spines

Basic score uses graded response with score range 0-90

Modified score uses binary response with score range 0-30

MASES enthesis index

•Reduced number of sites (13)

•Removed grading of tenderness (binary response)

•Avoided joint margins

•Better reliability

• 1st Costochondral joints

•7th costochondral joints

•Iliac crests

•Ant sup iliac spines

•Insertion of Achilles tendons

•lumbar spinous processes

•Post sup iliac spines

SPARCC enthesis index•8 sites

•Not graded

•Reliability shown in SPARCC study (Gladman et al. J Rheum 2004; 31(6):1126-1131)

•Greater tuberosity of humerus

•Insertion of Achilles tendons

•Insertion of plantar fascia

•Tibial tuberosity

MAJOR enthesis index

•Iliac crests

•Greater trochanter of femur

•Medial and lateral condyles of femur

•Insertion of Achilles tendons

•Insertion of plantar fascia

Graded as present/absence of tenderness

Reliability of enthesitis indicesResults from INSPIRE study

Psoriatic arthritis Ankylosing spondylitis

MAJOR 0.70 (0.5 – 0.89)

MASES 0.56 (0.34 – 0.82)

SPARCC 0.81 (0.64 – 0.93)

Figures are ICC (95% CI)

A new index for psoriatic arthritis

• 28 Ss with ‘active’ psoriatic arthritis starting treatment with new DMARDs

• All had enthesitis assessed at each of 5 visits over 6 months

• MEI (x2), MASES, SPARCC, MAJOR

• On final dataset performed data reduction using method of Heuft-Dorenbosch

Heuft-Dorenbosch L, Spoorenberg A, van Tubergen A, Landewe R, van der Tempel H, Mielants H et al. Assessment of enthesitis in ankylosing spondylitis. Annals of the Rheumatic Diseases 2003; 62:127-132.

A new index for psoriatic arthritis

• All MEI entheseal points graded to binary

• Frequency tables – entheseal point found to be most frequently tender, noted, and these patients not included in next ‘round’

• Process repeated until 80% assessments included

• 80% of assessments included after just 3 ‘rounds’– 1st round: right lateral epicondyle (49%)– 2nd round: right medial femoral condyle (70%)– 3rd round: right PSIS, Cx spinous process and

left Achilles insertion were equal (80%)

• LENIN: right and left lateral epicondyle humerus, right and left medial femoral condyle, right and left AT insertion (max 6)

A new index for psoriatic arthritis

Change in enthesis scores following treatment change

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11.5

22.5

33.5

Basel

ine

One

mon

th

Three

month

s

Six m

onths

MEI (0.40)MEI mod (1.03)MASES (0.76)MAJOR (1.19)SPARCC (1.05)LENIN (1.19)

MEI scores are divided by 10

Relationship between enthesis indices and other measures of disease activity

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-0.4

-0.2

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0.6

Sp

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CRP

VASphys

VASpt

Tender

Swollen

LDI

MEItotal

MASES

SPARCC

MAJOR

LENIN

Values >±0.2 are significant

Assessment of enthesitis in psoriatic arthritis

• Indices developed in patients with ankylosing spondylitis seem to function well in psoriatic arthritis – Repeatability– Responsiveness– Relation to other measures of disease activity

• New index derived from psoriatic arthritis population also functions well, although possibly not as well, has good effect size, and is quick and simple to perform

The OMERACT filter

• Truth– Poor relationship between clinical and U/S detected enthesitis– Juxta-articular position of entheses may lead to confounding with

articular pain

• Discrimination – All indices able to discriminate between states of low and high

disease activity (data not shown)– All indices show good responsiveness and effect sizes

• Feasability– LENIN is quickest and easiest but all others, excepting MEI, are

also simple to perform

Acknowledgements

• Rose Hellaby Trust supported Paul Healy

• Sanofi-Aventis provided funding for the study and the MRI scans (dactylitis)