Comparative Effect of Dual-Combination Antihypertensive Regimens on Reducing 24-Hour Systolic Blood Pressure Variability and Modifying Nocturnal Dipping Shifts: A Retrospective Cohort Study.

OBJECTIVES: This retrospective cohort study evaluated the real-world clinical effects of four dual-combination antihypertensive regimens on 24-hour ambulatory blood pressure variability (BPV) and circadian rhythm modifications over a 24-week period. METHODS: A total of 302 adults with primary hypertension were evaluated across parallel cohorts: an angiotensin-converting enzyme inhibitor plus calcium channel blocker group (ACEi+CCB, n = 76), an angiotensin II receptor blocker plus thiazide diuretic group (ARB+Thiazide, n = 75), a beta-blocker plus thiazide group (BB+Thiazide, n = 74), and a calcium channel blocker plus beta-blocker group (CCB+BB, n = 77). 24-hour systolic blood pressure (SBP) standard deviation (SD), Coefficient of Variation (CV), and night-to-day SBP ratios were analyzed to assess hemodynamic variations independent of absolute blood pressure lowering. RESULTS: While all regimens significantly reduced mean office and 24-hour ambulatory blood pressure, the ACEi+CCB combination demonstrated a significantly greater reduction in the 24-hour systolic CV from baseline to week 24 (from 10.35% ± 1.25% to 7.45% ± 0.92%, a relative drop of -28.0%) compared to the ARB+Thiazide (-15.1%), CCB+BB (-14.4%), and BB+Thiazide (-4.8%) cohorts (p < 0.001 after adjusting for absolute BP reduction). Additionally, the ACEi+CCB group achieved a significant downward shift in the continuous night-to-day SBP ratio from 0.96±0.04 to 0.91 ± 0.03 (p < 0.001), outperforming the ARB+Thiazide and BB+Thiazide arms. Treatment compliance (92%-95%) and overall adverse event rates (7.1%-9.7%) remained comparable across all groups. CONCLUSIONS: Dual therapies show class-dependent effects on BPV and circadian rhythm; ACEi+CCB most effectively reduces 24-hour systolic fluctuations.odifications, with the ACEi+CCB combination yielding the most pronounced reductions in 24-hour systolic fluctuations.