Losartanın Yeni Tanı Hipertansiyon Hastalarının Hematolojik Parametrelerine ve Trombosit Agregasyonuna Etkisi

Year 2015, Volume: 16 Issue: 3, 91 - 96, 01.12.2015

Mustafa Ünübol İrfan Yavaşoğlu Bilal Acar Gürhan Kadıköylü Zahit Bolaman

Abstract

Amaç: Hipertansiyon artmış trombosit fonksiyonu ile ilişkilidir. Bazı antihipertansif ilaçların anti-trombosit aktiviteleri vardır. Biz bu çalışmada, losartanın adenozin difosfat (ADP), kollajen, epinefrin, ristosetin ile trombosit agregasyonuna, diğer hematolojik ve enflamatuvar parametreler üzerine etkilerinin araştırılmasını amaçladık Gereç ve Yöntem: Çalışmaya yeni tanı hipertansiyonlu ortalama yaşı 54±8 yıl olan 19’u kadın, 6’sı erkek 25 hasta alındı. Yüksek
kan basıncını önleme, saptama, değerlendirme ve tedavi üzerine Birleşik Komite’nin yedinci raporuna göre tüm hastaların, evre 1-2
esansiyel hipertansiyon tanısı mevcuttu. Başlangıç kan basınçları ölçüldü ve her bir hastaya diyet, egzersiz gibi yaşam tarzı değişikliği
ile birlikte losartan 100 mg/gün tedavisi başlandı. Tedavi öncesi ristosetin, epinefrin, kollagen ve ADP ile trombosit agregasyonu
değerlendirildi. Ayrıca tam kan sayımları ölçüldü. Trombosit agregasyon testleri ve kan basıncı ölçümleri tedaviden 8 hafta sonra
tekrar değerlendirildi.
Bulgular: Losartan ile 8 haftanın sonunda sistolik ve diyastolik kan basıncında anlamlı düşüş saptandı (p<0,001). Tedavi sonrası, ADP,
kollajen ve epinefrin seviyeleri ile trombosit agregasyonunda anlamlı farklılık saptanmadı (p>0,05). Ristosetin ile agregasyon önemli
ölçüde azaldı (p=0,027). Aynı zamanda, önemli ölçüde düşük hemoglobin ve hematokrit seviyeleri gözlemlendi (p=0,034 ve 0,039,
sırasıyla).
Sonuç: Losartan, hemoglobin ile hematokrit seviyelerinde ve ristosetinle trombosit agregasyonunda önemli ölçüde düşüş sağlayarak
antihipertansif etkisinden bağımsız aktiviteler ortaya koyabilir. Bu sayede aterosklerozun ve trombozun önlenmesinde faydalı olabilir.

Keywords

Losartan, trombosit agregasyon, hemoglobin, hipertansiyon

The Effect of Losartan on Platelet Aggregation and Hematological Parameters in Patients with Newly Diagnosed Hypertension

Abstract

Objective: Hypertension is associated with increased platelet function. Some antihypertensive drugs have antiplatelet activity. In this study, we aimed to investigate the effects of losartan on platelet aggregation induced by adenosine diphosphate (ADP), collagen, epinephrine, ristocetin, other hematological and, inflammatory parameters. Materials and Methods: Twenty-five patients (19 female, 6 male; mean age: 54±8 years) with newly diagnosed hypertension were included in the study. All patients were with stage 1-2 essential hypertension according to the seventh report of the Joint National Committee on prevention, detection, evaluation, and treatment of high blood pressure. Initial blood pressure measurement was performed in all patients and losartan 100 mg/daily together with life style changes, such as diet and exercise was started. Platelet aggregation was evaluated with the use of ristocetin, epinephrine, collagen, and ADP. Complete blood count was also done. Platelet aggregation tests and blood pressure measurements were repeated after 8 weeks of therapy. Results: Systolic and diastolic blood pressure significantly decreased with losartan after 8 weeks (p<0.001). After treatment, there was no significant difference in platelet aggregation with ADP, collagen, and epinephrine (p>0.05). The aggregation with ristocetin significantly decreased (p=0.027). Besides, significantly lower hemoglobin and hematocrit levels were observed (p=0.034, p=0.039, respectively). Conclusion: Losartan may produce independent activities apart from its antihypertensive effects by providing significant reductions in platelet aggregation with ristocetin, and in hematocrit levels with hemoglobin. Therefore, it may be beneficial in the prevention of atherosclerosis and thrombosis.

Keywords

Losartan, platelet aggregation, hemoglobin, hypertension

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