PREVALENCE OF SUBCLINICAL GIANT CELL ARTERITIS IN PATIENTS WITH POLYMYALGIA RHEUMATICA
Authors: De Miguel E. et al.
Whether a subclinical Giant Cell Arteritis (GCA) is hidden behind a Polymyalgia Rheumatica (PMR) is of high clinical interest.
296 patients of a county in Southern Norway were prospectively followed over 35 years to determine the mortality associated with PMR. Diagnosis was established using the criteria of Bird between 1987 and 1997. Patients were follo
Eight European centers studied newly diagnosed patients with PMR who fulfilled the 2012 EULAR/ACR Provisional Classification Criteria, without symptoms or signs suggestive for GCA. All patients underwent ultrasound (US) examination of arterial territories (i.e. temporal, common carotid, subclavian and axillary arteries). Patients with positive halo signs or with an intima-media thickness ≥0.34mm for frontal and parietal TA, 0.42mm for common TA, and ≥1mm for common carotid, axillary and subclavian arteries were considered to have subclinical GCA.
Of a total of 258 patients, 137 (53.1%) were female with a mean age of 73±8.4 years. A halo sign was found on at least one of the examined arteries in 56/258 patients (21.7%). Data compatible with the diagnosis of GCA was found in 41 cases (19%): 10 (24.3%) had only temporal artery involvement (“cranial” GCA), 27 (65.8%) had an extra-cranial artery involvement and 4 (9.8%) a mixed form with both cranial and extra-cranial artery involvement.
Collectively, one fifth of PMR patients without symptoms or signs of GCA showed ultrasound findings consistent with the diagnosis of GCA, with a predilection for extra-cranial artery involvement. The data highlight the need to carefully search for GCA and to inform the patient about a potential vascular involvement. However, the %-age of positive results and the characteristics of the findings (mainly extra-cranial GCA) do not oblige to systematically perform imaging examinations in case of classical PMR.