Patients with primary Sjogren’s syndrome were at increased risk of various types of cardiovascular morbidity, a meta-analysis determined.
In an analysis that included more than 65,000 patients, the risk for coronary morbidity among Sjogren’s syndrome patients was more than 30% higher than for the general population, with a relative risk (RR) of 1.34 (95% CI 1.06-1.68, P=0.01), according to Jacques Morel, MD, PhD, of the University of Montpellier in France, and colleagues.
In addition, the risk for cerebrovascular morbidity was increased to an even greater extent (RR 1.46, 95% CI 1.43-1.49, P<0.00001), the researchers reported online in Arthritis Care & Research.
“Primary Sjogren’s syndrome is characterized by lymphocytic infiltration of the exocrine glands (mainly salivary and lacrimal) and is responsible for oral and eye dryness and by B-cell hyperactivity,” they wrote.
It primarily afflicts women at about age 50.
Patients with other chronic autoimmune diseases such as lupus and rheumatoid arthritis have a well recognized risk for cardiovascular disease, which is credited largely to systemic inflammation, but risk estimates for Sjogren’s syndrome have been conflicting.
Therefore, to provide a clearer picture of the risks, Morel and colleagues conducted a systematic literature review, identifying 14 studies that had sufficient data for a meta-analysis.
The studies included mostly women whose mean age was 55 and whose disease duration was 7 years.
In five studies that included 24,133 patients with Sjogren’s syndrome and 460,266 controls, the number of coronary events were 7,799 and 84,772, respectively. In four studies that included 25,242 patients with Sjogren’s syndrome and 570,183 controls, the number of cerebrovascular events were 605 and 11,367, respectively.
For thromboembolic events, two studies included 16,090 Sjogren’s syndrome patients and 548,218 controls. In these groups, there were 100 and 15,607 events, respectively, with an RR in the Sjogren’s group of 1.78 (95% CI 1.41-2.25, P<0.00001).
For heart failure, three studies included 5,920 Sjogren’s syndrome patients and 9,911 controls who had 609 and 358 events, respectively, with an odds ratio of 2.54 (95% CI 1.30-4.97, P<0.007) for the Sjogren's syndrome patients.
Cardiovascular mortality, however, did not appear to be elevated. In two studies that included 745 patients, there were 25 cardiac-related deaths (RR 1.48, 95% CI 0.77-2.85, P=0.24).
Possible explanations for the lack of significant risk of cardiovascular mortality were lower rates of smoking and less use of corticosteroids among patients with Sjogren’s syndrome compared with patients with rheumatoid arthritis and systemic lupus erythematosus, conditions in which cardiovascular mortality is clearly elevated.
While chronic systemic inflammation increases cardiovascular risk in immune-mediated inflammatory diseases such as Sjogren’s syndrome, other factors also may be in play. Some researchers have identified a high prevalence of atherosclerosis detected by endothelial dysfunction, abnormalities of the ankle brachial index, or carotid intima-media thickening, particularly among patients with long disease duration.
In the studies that reported on cardiovascular risk factors, patients with Sjogren’s syndrome had high rates of hyperlipidemia and hypertension, which also could contribute to atherosclerosis.
The presence of circulating autoantibodies could further raise risks. In particular, anti-SSA/Ro and anti-SSB/La antibodies have often been detected in patients with Sjogren’s syndrome who have cardiovascular comorbidities and systemic involvement.
“Prospective studies are needed to further study the association between cardiovascular events and primary Sjogren’s syndrome,” including the potential contributions of steroids and other medications.
“However, rheumatologists should be aware of this increased risk in order to propose screening for cardiovascular comorbidities and specific preventive interventions for patients with primary Sjogren’s syndrome,” the authors concluded.
A major limitation of the study was high heterogeneity among the studies included in the meta-analysis. For instance, heterogeneity assessed using the I2 statistic was 94% in the studies of thromboembolic events and 85% in the heart failure studies.
The authors reported no financial disclosures.