Acute-phase reactants and the risk of relapse/recurrence in polymyalgia rheumatica: a prospective followup study.
OBJECTIVE
To determine laboratory parameters that may be useful in identifying polymyalgia rheumatica (PMR) patients who require long-term corticosteroid therapy.


METHODS
A prospective followup study of 94 consecutive untreated patients with PMR were assessed for relapse/recurrence for a mean of 39 months. This cohort represented all the patients diagnosed over a 4-year period in 2 Italian secondary referral centers. Patients were monitored for clinical signs and symptoms, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and serum interleukin-6 (IL-6). IL-6 levels were also measured in 43 controls matched to the patients for age and sex.


RESULTS
The ESR was elevated in 91.5% of the patients prior to therapy initiation, as were CRP in 98.9% and serum IL-6 in 92.6%. Forty-seven (50.0%) patients had at least 1 relapse/recurrence during the followup period and 24 (25.5%) had at least 2. After 4 weeks of prednisone therapy, ESR was elevated in 13.2% patients, CRP in 41.9%, and serum IL-6 in 37.2%. IL-6 levels remained persistently elevated in 9.9% and CRP in 8.7% of patients during the first year of followup, whereas no patient had persistently elevated ESR. Persistently elevated CRP and IL-6 levels were significantly associated with an increased risk of relapse/recurrence. In particular, patients with persistently elevated levels of IL-6 during the first year of therapy had the highest relative risk.


CONCLUSIONS
Despite the control of clinical symptoms, corticosteroids do not adequately control the inflammatory process in a subset of patients with PMR who have persistently elevated levels of CRP and IL-6 and who have a higher risk of relapsing.
Salvarani
Carlo
C
Arcispedale S. Maria Nuova, Reggio Emilia, Italy. carlo@asmn.re.it
Cantini
Fabrizio
F
Niccoli
Laura
L
Macchioni
Pierluigi
P
Consonni
Dario
D
Bajocchi
Gianluigi
G
Vinceti
Marco
M
Catanoso
Maria Grazia
MG
Pulsatelli
Lia
L
Meliconi
Riccardo
R
Boiardi
Luigi
L
D000209:Acute-Phase Proteins / Q000276:immunology / Q000378:metabolism*; D000368:Aged; D000369:Aged, 80 and over; D018501:Antirheumatic Agents / Q000008:administration & dosage; D001799:Blood Sedimentation; D002097:C-Reactive Protein / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D005938:Glucocorticoids / Q000008:administration & dosage*; D006801:Humans; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D008875:Middle Aged; D011111:Polymyalgia Rheumatica / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology / Q000276:immunology*; D011237:Predictive Value of Tests; D011239:Prednisolone / Q000008:administration & dosage*; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors
D000209:Acute-Phase Proteins; D018501:Antirheumatic Agents; D005938:Glucocorticoids; D015850:Interleukin-6; D002097:C-Reactive Protein; D011239:Prednisolone