Primary Sjögren's syndrome independently promotes premature subclinical atherosclerosis

Cardiovascular comorbidities are common in patients with autoimmune diseases. This study investigates the extent of subclinical atherosclerosis in patients with primary Sjögren's syndrome (pSS). Correlations with clinical factors such as organ involvement (OI) or disease activity were analysed and oxLDL antibodies (oxLDL ab) were measured as potential biomarkers of vascular damage.

Patients with pSS were consecutively included from the rheumatology outpatient clinic. Age- and sex-matched controls were recruited (2:1 ratio). Data collection was performed by a standardised questionnaire and Doppler ultrasound to evaluate the plaque extent and carotid intima-media thickness (cIMT). Propensity score matching included all cardiovascular risk (CVR) factors and corresponding laboratory markers.

Data were available for 299 participants (199 pSS/100 controls), aged 59.4 years (50.6-65.0), 19.1% male. After matching, the pSS cohort had greater cIMT (p<0.001) and plaque extent (OR=1.82; 95% CI 1.14 to 2.95). Subgroup analyses of patients with pSS revealed that OI was associated with increased cIMT (p=0.025) and increased plaque occurrence compared with patients without OI (OR=1.74; 95% CI 1.02 to 3.01). OxLDL ab tended to be lower in patients with plaque (p=0.052). Correlations of higher Oxidized Low Density Lipoprotein (oxLDL) ab with EULAR Sjögren's Syndrome Disease Activity Index (p<0.001) and anti-Sjögren's-syndrome-related antigen A autoantibodies (SSA/Ro antibodies) (p=0.026) were observed.

Subclinical atherosclerosis occurs earlier and more severely in patients with pSS. The difference in cIMT between pSS and controls seems mainly driven by patients with OI, suggesting that this subgroup is particularly at risk. OxLDL ab might protect against atherosclerotic progression in patients with pSS. CVR stratification and preventive medications such as Hydroxymethylglutaryl-CoA (HMG-CoA) reductase inhibitors should be discussed and further longitudinal studies are needed.