CRP and cardiovascular disorder: For example, fourteen cross-over RCTs (18 publications) found that individuals with cardiovascular diseases who used HEPA air purifiers at home experienced a -2.28 mmHg [95% CI, -3.92 to -0.64] reduction in systolic blood pressure, indications of improvements in reactive hyperemia index (RHI) (0.10 [-0.04 to 0.24]), diastolic blood pressure (-0.35 [-1.52 to 0.83] mmHg), pulse pressure (PP) (-0.86 [-2.07 to 0.34] mmHg), and C-reactive protein (-0.23 [-0.63 to 0.18] mg/L) following indoor air purification compared to those who did not use air purifiers [126].