Blood Pressure Dipping May Be a Marker of Cardiovascular Function in Pediatric-Onset SLE

The loss of normal nocturnal decrease in blood pressure (BP) may be a marker of endothelial dysfunction and subclinical atherosclerosis in patients with pediatric-onset systemic lupus erythematosus (pSLE), according to study results published in Arthritis Research & Therapy.

Blood pressure nondipping is often used as a measure of cardiovascular risk in clinical practice, but its prognostic capacity for vascular function and subclinical atherosclerosis remains unclear.

Investigators conducted a cross-sectional study with data of children and adolescents with pSLE who received comprehensive noninvasive cardiovascular testing at a tertiary rheumatology clinic. Patients had both standard BP assessment at a clinic visit and 24-hour ambulatory BP monitoring (ABPM), during which systolic and diastolic BP were measured every 20 minutes while patients were awake and every 30 minutes while they were asleep. The primary outcome was the presence of BP nondipping, defined as a <10% decrease from mean daytime to mean night time systolic or diastolic BP. Secondary outcomes included hypertension and average 24-hour systolic or diastolic BP load, or the proportion of BP values elevated above the 95th percentile. Patients also received peripheral endothelial function testing, aortic stiffness testing, and carotid intima-media thickness testing that was considered a structural measure of subclinical atherosclerosis. Pearson and Spearman rank correlation coefficients were used to assess the relationship between nocturnal BP nondipping and vascular outcomes. Analyses were adjusted for the typical cardiovascular risk factors.

The study cohort included 20 patients with pSLE, among whom 17 (85%) were girls. Mean age and disease duration were 16.5±2.7 and 3.2±2.1 years, respectively. Most patients (75%) had inactive disease. The prevalence of BP nondipping was 50%, which occurred in the absence of hypertension. Patients with nondipping vs adequate dipping BP had higher mean body mass index (P =.05) and high-density lipoprotein levels (P <.05). Reduced diastolic BP dipping was associated with poorer endothelial function (r=0.5; P =.04), and greater intima-media thickness was seen in patients with BP nondipping vs dipping (mean deviation score, 3.0 vs 1.6; P =.02). Higher systolic and diastolic BP load were associated with increased aortic stiffness (P =.01 and P <.01, respectively), but not with endothelial function or intima-media thickness.  

These data suggest that BP nondipping may be a prognostic indicator of endothelial dysfunction and atherosclerotic changes in patients with pSLE with low disease activity.

“ABPM has a promising role in risk stratification and understanding heterogeneous mechanisms of cardiovascular disease in pSLE,” the investigators concluded.

Reference

Chang JC, Xiao R, Meyers KE, et al. Nocturnal blood pressure dipping as a marker of endothelial function and subclinical atherosclerosis in pediatric-onset systemic lupus erythematosus [published online June 3, 2020]. Arthritis Res Ther. doi:10.1186/s13075-020-02224-w