Background/Purpose: SLE is considered a coronary heart disease equivalent and aggressive management of all traditional risk factors is recommended. Hypertension is a major problem in SLE. Seventy-five percent of patients in our cohort are hypertensive. The presence of hypertension in SLE increases the risk of cardiovascular events 2.66-fold, as well as the risk of stroke and poor renal outcomes. Guidelines for diagnosis and treatment of hypertension focus only on mean systolic blood pressure (SBP). Our objective was to evaluate the prognostic significance of visit-to-visit variability in blood pressure, maximum blood pressure reached, and episodic hypertension on cardiovascular events in SLE.

Methods: The analysis was based on 1340 different patients with an average duration of follow-up of 74 months. For each month of follow-up for a patient in the cohort, the previous 8 blood pressure measurements were included in the analysis. The following variables were calculated: mean prior SBP and diastolic blood pressure (DBP), standard deviation of prior SBP and DBP, coefficient of variation of prior SBP and DBP, maximum prior SBP and DBP, and minimum prior SBP and DBP. Based on the maximum and minimum blood pressure values, the following categories were created: stable normotension (maximum always <= 140mmHg), episodic moderate hypertension (minimum <= 140mmHg, maximum 140-179mmHg) episodic severe hypertension (minimum <=140, maximum 180+) and stable hypertension (minimum > 140). This information was then linked with whether the patient had a cardiovascular event (CVE) in that month. Person-months were aggregated, and the risks of a CVE by monthly characteristics were calculated. Person-months after a previous CVE were excluded. CV events were defined as either stroke, myocardial infarction, incident angina, a coronary procedure (CABG or PCI), or claudication.

Results:

There were 105 CV events with a rate of 12.6 per thousand person-years. Visit-to-visit SBP variability of ≥14mmHg (RR=1.9 (1.0, 3.3), p<0.05) and DBP variability of ≥9mmHg (RR=2.5 (1.3, 4.9), p<0.01) was predictive of future CVE. A single, maximum value of SBP≥150mmHg or DBP ≥ 92mmHg were strong predictors of CVE (RR=3.7 (1.7, 8.0), p<0.01). Episodic moderate (RR=2.0 (1.3, 3.2), p<0.01) and episodic severe hypertension (RR=3.1 (1.5, 6.5), p<0.01) were both highly associated with future CVE. Mean systolic blood pressure of >130mmHg was a strong, independent predictor of CVE (rate ratio 3.3 (0.6, 6.8), p<0.01). When data were controlled for mean systolic blood pressure, no other variable was statistically associated with CVE.

Conclusion:

Mean systolic blood pressure is the dominant predictor of cardiovascular events in our cohort. However, visit-to-visit variability in SBP ≥14mmHg and DBP ≥9mmHg, episodic hypertension, and single, isolated maximum values of SBP≥150mmHg and DBP ≥ 92mmHg were all highly associated with cardiovascular events, drawing attention to the false reassurance of a few normal blood-pressure readings and the need for aggressive blood pressure management in SLE patients.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/prognostic-significance-of-visit-to-visit-variability-maximum-systolic-blood-pressure-and-episodic-hypertension-in-sytemic-lupus-erythematosus/