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A Pilot Study on the Effect of Angiotensin Receptor Blockers on Platelet Aggregation in Hypertensive Patients- A
Arun Suresh1, Narendranath Sanji2, Pallavi Mahadeva Kamath1
1Post Graduate, Department of Pharmacology, JJM Medical College , Davanagere, Karnataka, India .
Insights
Angiotensin II type 1 Receptor Blockers (ARBs) demonstrate antiplatelet activity, as evidenced by a significant increase in bleeding time in hypertensive patients. This finding suggests ARBs may play a role in reducing thrombosis risk in cardiovascular disease.
Area of Science:
- Cardiovascular Medicine
- Pharmacology
- Hematology
Background:
- Thrombosis is a key factor in cardiovascular events, particularly in hypertensive patients.
- Increased platelet activity is a significant risk factor for cardiovascular disease.
- Angiotensin II type 1 Receptor Blockers (ARBs) are common antihypertensive agents, but their antithrombotic effects require further characterization.
Purpose of the Study:
- To investigate the in-vivo anti-aggregatory effects of Angiotensin II type 1 Receptor Blockers (ARBs) on platelets.
- To evaluate the potential antithrombotic properties of ARBs in patients with essential hypertension.
Main Methods:
- An observational pilot study involving 60 subjects: 30 patients with essential hypertension on ARBs and 30 normotensive controls.
- Bleeding Time (BT) was measured using the Duke method for both groups.
- Statistical analysis was performed using SPSS, comparing the groups with an unpaired t-test.
Main Results:
- The mean Bleeding Time (BT) in the ARB group was significantly higher (2.488 min ± 0.0361 SEM) compared to the control group (1.998 min ± 0.0362 SEM).
- The observed difference in BT was statistically significant (p<0.001).
- The average duration of ARB treatment in the study group was 2.933 years.
Conclusions:
- Angiotensin II type 1 Receptor Blockers (ARBs) possess antiplatelet activity.
- The increased Bleeding Time (BT) in the ARB-treated group indicates a reduction in platelet aggregation, suggesting an antithrombotic effect.
Introduction:
Thrombosis is an invariable component contributing to cardiovascular events in patients with hypertension. One of the risk factors of cardiovascular disease is increased platelet activity. One among the widely used antihypertensive agents are Angiotensin II type 1 Receptor Blockers (ARBs). Even though there are many studies involving antihypertensive agents, their antithrombotic properties remain elusive and not fully characterized.
Aim:
To evaluate the anti-aggregatory effect of ARBs on platelets in-vivo.
Materials And Methods:
A total of 60 subjects were included in this observational pilot study conducted in the medicine out patient department of JJM Hospital, Davanagere, Karnataka, India. Among them, 30 patients with essential hypertension attending Medicine OPD of a tertiary care hospital, who were on ARB for at least one month, were enrolled into study group. The control group consisted of 30 normotensive subjects who were not on any drug affecting platelet function. The Bleeding Time (BT) was evaluated for both the groups using Duke method of BT estimation. Data was analysed using SPSS software version 20. The test group was compared with control group using student's unpaired t-test.
Results:
The mean BT of study group was 2.488 minutes ± 0.0361 Standard Error of Mean (SEM) and that of control group was 1.998 minutes ± 0.0362 SEM. The result was statistically significant (p<0.001). The average duration of treatment was 2.933 years.
Conclusion:
ARB have antiplatelet activity. Increase in BT in ARB group when compared with that of control group is a reflection of antiplatelet activity.
