Renin inhibitors versus angiotensin converting enzyme (ACE) inhibitors: what is the effect on reducing blood pressure?

This study investigated renin inhibitors (RI) and angiotensin-converting enzyme inhibitors (ACEI) in hypertension. They found that RI may reduce blood pressure (BP) more than ACEI, but mortality and heart attack risk was similar for both drug types.

Hypertension or high blood pressure (BP) is a common condition. It can be controlled in a number of ways. Lifestyle adjustments can improve BP control. Anti-hypertensive drugs can also be used. There are many types of drugs used to lower BP. 

Renin-inhibitors (RI) reduce BP by blocking the enzyme renin. Renin is produced in the kidneys and stimulates the production of a protein called angiotensin II (AGII). This causes blood vessels to narrow and increases BP. Angiotensin-converting enzyme inhibitors (ACEIs) block ACE which converts angiotensin I to AGII. Blocking ACE also reduces BP.  Both RI and ACEI reduce BP. RIs include drugs such as aliskiren (Tekturna) and ACEIs include drugs such as captopril (Capoten), enalapril (Vasotec), ramipril (Altace), and others. It is unclear if RI or ACEI are more effective at reducing BP and the risks of complications from high BP such as heart attacks, strokes, or death.  

This study included 11 clinical trials evaluating RI and ACEI for hypertension. Overall, these included 13,627 patients. The average follow-up time was 4 weeks to 36.6 months.

The mortality risk and the risk of having a heart attack was not significantly different in patients treated with RI or ACEI. Also, there was no difference in side effects between the 2 drugs. RI reduced both systolic (BP during a heartbeat; by 1.72 mmHg) and diastolic (BP when the heart relaxes between beats; by 1.18 mmHg) BP more than ACEI.

The authors concluded that RI may decrease BP more than ACEIs, while the risk of complications from high BP was similar between both drugs.

The evidence analyzed was considered medium to low. More controlled studies are needed.

If you have any concerns regarding hypertension management please consult with your doctor.