Women with systemic lupus erythematosus (SLE) who experience hypertensive disorders of pregnancy may have a higher rate of cardiovascular outcomes after pregnancy, as well as a higher rate of hypertension later in life, than do those without maternal hypertension, according to findings from a Swedish population-based, longitudinal cohort study.
“Premature CVD [cardiovascular disease] 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. Our data confirm that women who experience a hypertensive disorder in pregnancy [HDP] are at greater risk of developing hypertension after pregnancy, and that this association is also evident for women with SLE. Women with SLE and HDP were also at increased risk of CVD, particularly stroke, at young ages and should be monitored closely and consider treatment to attenuate risk,” wrote first author Julia F. Simard, ScD, of Stanford (Calif.) University and colleagues in Arthritis Care & Research.
To reach those conclusions, the researchers identified 3,340 women in the Swedish Medical Birth Register with their first singleton delivery during 1987-2012. They matched each of the 450 women with prevalent SLE from the Medical Birth Register to 5 women without SLE in the National Patient Register based on sex, birth year, calendar time, and county of residence.
During a median follow-up period of nearly 11 years, women with SLE had an unadjusted incidence rate of incident cardiovascular outcomes of 50 cases per 10,000 person-years versus 7.2 for women without SLE. Cardiovascular outcomes included fatal and nonfatal acute MI, fatal and nonfatal stroke, transient ischemic attacks, unstable angina, and heart failure. A history of HDP in women with SLE, including preeclampsia, was linked with about a twofold higher rate of cardiovascular outcomes regardless of multiple sensitivity analyses, both before and after adjusting for maternal age at delivery, county of birth, education, body mass index, and first-trimester smoking.
The researchers found that the hazard ratio for cardiovascular outcomes in women with SLE and HDP was about eight times higher than the hazard ratio for women without SLE but with HDP, but the relative rarity of cardiovascular events seen during the follow-up period, particularly among women without SLE, made it so that they “could not confirm established associations between HDP and CVD, possibly due to the relatively short follow-up time given that premenopausal CVD is rare among women free of SLE.”
HDP was associated with a threefold higher risk for incident hypertension later in life regardless of SLE status, even though the unadjusted incidence rate was 524 cases per 10,000 person-years among women with both SLE and HDP, compared with 177 per 10,000 person-years among women with HDP in the general population, which sensitivity analyses suggested “was not due to misclassification of antihypertensive use for renal disease in women with SLE nor antihypertensive use for possible HDP in subsequent pregnancies,” the researchers wrote.
Several authors reported research grants from the National Institutes of Health, the Karolinska Institute, the Swedish Research Council, Swedish Heart-Lung Foundation, Stockholm County Council, the King Gustaf V 80th Birthday Fund, the Swedish Rheumatism Association, and Ingegerd Johansson’s Foundation that helped to fund the study. All authors reported having no competing interests.
SOURCE: Simard JF et al. Arthritis Care Res. 2020 Jan 31. doi: 10.1002/acr.24160.