Cardiovascular risk double in SLE with hypertensive disorders of pregnancy
Among patients with systemic lupus erythematosus, those with hypertensive disorders of pregnancy are at twice the risk for cardiovascular outcomes as those without such disorders, according to data published in Arthritis Care & Research.
“[Hypertensive disorders of pregnancy] broadly appears to increase cardiovascular disease (CVD) incidence in women, and preeclampsia, specifically, has been associated with a higher incidence of cardiovascular events, including stroke later in life,” Julia F. Simard, ScD, SM, of the Stanford School of Medicine, and colleagues wrote. “Whether pregnancy is a stress test that unmasks endothelial vulnerability which manifests as [hypertensive disorders of pregnancy] or whether the maternal hypertensive disorder itself causes damage leading to CVD is unknown.”
“Women with systemic lupus erythematosus are at increased risk of CVD, including stroke,” they added. “Hypertension and systemic inflammatory disease, such as SLE, are well established risk factors for preeclampsia. The relationship between [hypertensive disorders of pregnancy] and future CVD is complex and may differ between women with and without SLE.”
To analyze the role of SLE in the relationship between hypertensive disorders of pregnancy and cardiovascular outcomes, Simard and colleagues studied data from the Swedish Birth Register and the National Patient Register. The researchers identified 450 singleton first deliveries among patients with prevalent SLE between 1987 and 2012. As a comparison group, 2,890 singleton first deliveries among nulliparous women without SLE were also identified, who were then matched to the SLE group based on sex, birth year, calendar time and county of residence.
Discharge diagnoses for hypertensive disorders of pregnancy, cardiovascular outcomes and hypertension were identified using ICD codes in the National Patient Register. The researchers calculated adjusted HRs for the link between hypertensive disorders of pregnancy and cardiovascular outcomes in separate models among patients with and without SLE. They then studied the additive and multiplicative impact modification, using relative excess risk from interaction and Cox models, accounting for SLE and hypertensive disorders of pregnancy.
According to the researchers, hypertensive disorders of pregnancy were reported among 20% of patients with SLE, compared with 7% among those without. Among patients with SLE, hypertensive disorders of pregnancy were linked with a twofold higher rate of cardiovascular outcomes, and a threefold higher rate of hypertension. Among those without SLE, hypertensive disorders of pregnancy were linked to higher hypertension incidence later in life.
“Premature CVD is a well-documented complication in women with SLE which is likely, at least in part, due to renal disease, prothrombotic [antiphospholipid antibodies] and systemic inflammation,” Simard and colleagues wrote. “Our data confirm that women who experience a hypertensive disorder in pregnancy are at greater risk of developing hypertension after pregnancy, and that this association is also evident for women with SLE. Women with SLE and [hypertensive disorders of pregnancy] were also at increased risk of CVD, particularly stroke, at young ages and should be monitored closely and consider treatment to attenuate risk.” – by Jason Laday
Disclosure: The researchers report no relevant financial disclosures.