To determine the prevalence of Raynaud's phenomenon (RP) in a large series of patients with primary Sjögren's syndrome (SS) and to identify the clinical and immunological features related to its presence.
In a cross sectional study, we investigated 320 consecutive patients with primary SS (294 women, 26 men; mean age at onset 60 yrs, range 16-87 yrs). All patients fulfilled 4 or more of the diagnostic criteria for SS proposed by the European Community Study Group in 1993. Diagnosis of RP in patients with SS was defined as intermittent attacks of digital pallor and/or cyanosis in the absence of any other associated disease or anatomical abnormalities.
RP was present in 40 (13%) patients. All were women, with a mean age of 57 yrs (range 18-78). RP preceded onset of sicca symptomatology in 18 (45%) patients. The main triggering factor was exposure to cold, which induced RP in all patients, while emotional stress was a factor in 12 patients, as was job related predisposition in 2. Fifteen (38%) patients required pharmacological treatment with calcium channel blockers (12 patients) or angiotensin converting enzyme inhibitors (2 patients) during colder months, and one patient required treatment with intravenous prostacyclin for ischemic complications. Compared with SS patients without RP, those with RP showed a higher prevalence of articular involvement (50 vs 31%; p = 0.031), cutaneous vasculitis (30 vs 11%; p = 0.003), antinuclear antibodies (95 vs 65%; p < 0.001), anti-Ro/SSA (59 vs 31%; p < 0.001) and anti-La/SSB antibodies (44 vs 20%, p = 0.003).
We found RP in 13% of patients with primary SS, in almost half of whom RP was the first autoimmune symptomatology. These patients constituted a subset of SS with a higher frequency of some extraglandular features and positive immunological markers. The clinical course of RP seems to be milder in patients with primary SS than in those with other systemic autoimmune diseases such as systemic sclerosis, with no vascular complications and pharmacological treatment needed in only 40% of patients.