Platelet hyperactivity in hypertensive older patients is controlled by lowering blood pressure

OBJECTIVE: Patients with hypertension tend to have a high prevalence of ath erothrombotic accidents. Platelet hyperactivity is frequently associated wi th hypertension. Because the vascular disease associated with hypertension evolves over the years, we investigated platelet activity parameters in a p opulation of older hypertensive patients with no other risk factors for car diovascular disease. PARTICIPANTS: We studied 34 older, nonsmoking patients (mean age 74 +/- 5 y ears) with uncomplicated hypertension before and after the normalization of blood pressure (BP) was achieved with the angiotensin-converting enzyme in hibitor quinapril alone or in combination with the Ca2+ antagonist nifedipi ne. MEASUREMENTS: Platelet aggregation, P-selectin (CD62) expression on the pla telet surface, serum levels of Interleukin-1 beta (IL-1 beta) and of Interl eukin-6 (IL-6), as well as plasma levels of soluble P-selectin and Endothel in-1 (ET-1), were analyzed. RESULTS: All platelet hyperactivity parameters were reduced significantly w ith the normalization of BP at the end of antihypertensive drug treatment ( systolic/diastolic: 186.2 +/- 2.7/103.4 +/- 1.1 mm Hg vs 135.0 +/- 1.3/85.9 +/- 1.9 mm Hg; P < .001). Those factors more strictly associated with endo thelium injury, such as ET-1 and IL-6, did not show variations. A significa nt correlation (Spearman Rank test) was observed among all platelet functio n parameters and blood pressure values. CONCLUSIONS: This study demonstrated that even in a population of older hyp ertensive patients with no other risk factor for atherogenic disease, norma lization of blood pressure induces a significant reduction of the parameter s of enhanced platelet hyperactivity independent of the action exerted, at the platelet level, by the antihypertensive drugs.