Ambulatory Blood Pressure in Patients With Rheumatoid Arthritis: Association With Immune Activation

Abstract

Objective. The prevalence of hypertension, a major cardiovascular risk factor, is increased in patients with rheumatoid arthritis (RA) and may be driven by immune activation. The purpose of this study was to determine if ambulatory 24-hour blood pressure (BP) is elevated in RA vs control participants and whether it is associated with immune activation. Methods. We conducted a cross-sectional study of 46 patients with RA and 23 control participants. Participants wore an ambulatory BP monitor that obtained diurnal BP every 15-30 minutes and nocturnal BP every 30 minutes. Inflammatory mediators in plasma were measured using an inflammation proteomics panel. Differences in BP measurements were assessed by Mann-Whitney U test, and association with inflammatory mediators was assessed by Spearman correlation. Results. Patients with RA and control participants had similar office BP, but median ambulatory systolic BP (SBP) measurements (24-hour [RA 121 mmHg vs control 116 mmHg; P = 0.01], diurnal [RA 128 mmHg vs control 120 mmHg; P = 0.003], and nocturnal [RA 112 mmHg vs control 103 mmHg; P = 0.002]) were higher in patients with RA. Patients with RA also had higher nocturnal diastolic BP (DBP; RA 63 mmHg vs control 57 mmHg; P = 0.02), but other DBP measurements were similar. Nocturnal BP dipping was less in patients with RA (12%) compared to control participants (16%; P = 0.02). In patients with RA, higher 24-hour and nocturnal SBPs and less nocturnal dipping were strongly correlated with a wide range of inflammatory mediators. Conclusion. Despite similar office measurements, 24-hour and nocturnal SBP measurements were higher in patients with RA than in control participants and were strongly associated with inflammation.