Abstract
Byline: Anirudh Palicherla, Internal Medicine, Creighton Univ Sch of Medicine, Omaha, NE; Mahmoud Ismayl, Creighton Univ, Omaha, NE; Khalid M Bashir, Internal Medicine, Creighton Univ Sch of Medicine, Omaha, NE; Tammy Burns, Mary Lanning Healthcare Hastings, Hastings, NE; Samuel J Pirruccello, Univ of Nebraska Med Cntr, Omaha, NE; Sarah Aurit, Creighton Univ, Omaha, NE; Daniel E Hilleman, Creighton Univ Sch of Pharmacy and Health Professions, Omaha, NE Introduction: The ACC/AHA hypertension guidelines recommended chlorthalidone (CTD) over hydrochlorothiazide (HCTZ) due to its longer half-life and proven reduction in major adverse cardiovascular events. The mechanism of the potential benefit of CTD compared to HCTZ has not been established. Unlike other thiazide diuretics, studies suggest that CTD may affect platelet aggregation, gene transcription, angiogenesis, and vascular permeability. We aimed to compare the antiplatelet effects of CTD versus HCTZ. Methods: We conducted a prospective, double-blind, randomized, three-way crossover study comparing the antiplatelet effects of CTD, HCTZ, and aspirin (ASA) in healthy volunteers [greater than or equal] 19 years of age. ASA was included in the study as a known control for inhibition of platelet aggregation. Whole blood aggregometry was used to assess the impact of treatments on platelet activation and aggregation. Results: Of the 40 subjects, 34 (85%) completed the 3-way crossover comparison. Six subjects were excluded due to non-compliance and adverse effects. Compared to ASA, both CTD and HCTZ had no antiplatelet effects (Table 1). There was no statistically significant difference between CTD and HCTZ in terms of platelet function. Conclusions: Although recent studies showed increased cardiovascular benefit with CTD compared to HCTZ, CTD and HCTZ do not have antiplatelet effects. Larger studies are needed to confirm our findings.