Background Young women with SLE are at greater risk for cardiovascular events (CVE) even in the relative absence of cardiovascular risk factors.1 They also have more pregnancy complications.2 We have previously demonstrated that pregnancy complications related to maternal-placental syndrome (MPS) are associated with an increased risk and accelerated development of CVE in parous women with SLE.3
However, it is still unknown if pregnancy and its complications – in the form of MPS - accelerate CVE in women with SLE or if SLE-related morbidity plays a more significant role.
Objectives To determine if parity and pregnancy complications were associated with accelerated development of CV events in women with SLE.
Methods Utilizing linked Swedish population registries, women with SLE born between 1951-71 were included. MPS was defined as hypertensive disorders of pregnancy, small-for-gestational-age, stillbirth and placental abruption. SLE-related morbidity was defined as inpatient admissions, renal disease, malignancies and infections. Outcome was any CVE, this included coronary artery disease, stroke, peripheral vascular disease and death from these causes. Hazard was determined using Cox proportional-hazards adjusting for cardiovascular risk factors and SLE-related morbidity. Survival was assessed using Kaplan-Meier's methods.
Results Of 3232 women with SLE identified, 2317 (72%) were parous. Median age was 49 years. Compared to the parous women, the non-parous women had more SLE-related morbidity [LM1], cardiovascular risk factors and CVE (15.1 vs. 8.5 [LM2] %). Amongst the parous women 23.3% (n=539) had a history of MPS. The incidence of CV events was highest amongst the non-parous group at 3.4 per 1,000 person-years (95%CI 2.91-4.07) followed by those who had pregnancies complicated by MPS (2.8 per 1,000 person-years (95% CI 2.2-3.6)). Hazard of a CVE was 2.2-fold higher in the non-parous group (HR 2.2; 95%CI 1.7-2.8) compared to 1.8-fold increase in those with MPS (HR 1.8; 95%CI 1.3-2.4). This hazard persisted after adjustment. The probability of a CVE-free survival was lowest in the non-parous group even when compared to those with MPS (p<0.001). (Figure 1)
Conclusions Pregnancy and its complications do not accelerate CVE to the same extent as SLE-related morbidity – which is more prevalent in the non-parous group. Non-parous women with SLE had the highest incidence and hazard of CVE; they developed accelerated CVE even when compared with women who have had a history of MPS complicating their pregnancies. It is possible that the more severe SLE that accelerates the development of CVE may also reduce fertility and the chances of successful pregnancy.
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Chakravarty EF, et al. Arth Rheum 2006;54:899-907.
Soh MC, et al. Ann Rheum Dis 2014;73:137.
Acknowledgements We would like to thank the Rose-Hellaby Medical Scholarship, BMFMS Bursary and APLAR Research Grant for the support of Dr. MC Soh.
Disclosure of Interest None declared