How low should you go? Lower blood pressure targets and cardiovascular risk

This study examined the most beneficial blood pressure targets for patients with hypertension and increased cardiovascular risk.

Hypertension (high blood pressure) affects roughly one billion people worldwide, particularly people over the age of 50. High blood pressure increases the risk of cardiovascular events, such as heart attack or stroke. Increased systolic blood pressure (the pressure when the heart is contracting) is especially associated with increased cardiovascular risk.

Treatment of high blood pressure can reduce the risk of heart attack by 15-25%, the risk of stroke by 35-40%, and the risk of heart failure (a weakened heart that can no longer pump blood effectively) by up to 64%. Current guidelines suggest a systolic blood pressure target of less than 140 mmHg to reduce risks. It is unclear whether a lower target (less than 120 mmHg) could further decrease cardiovascular risk.

The current study examined whether patients with high blood pressure experienced fewer cardiovascular events with a lower blood pressure target.

This study included 9361 patients with high blood pressure and an increased risk of cardiovascular events (due to kidney disease, cardiovascular disease, or those over the age of 75). Patients were randomly assigned to one of two groups. The intensive group had a treatment target of 120 mmHg. The standard group had a treatment target of 140 mmHg. Patients were seen once a month for 3 months, then every 3 months for an average of 3.26 years. Patients in both groups received similar blood pressure-lowering medications. Medications were adjusted as needed to maintain the blood pressure targets. Patients in the intensive group needed an average of 2.8 medications. Patients in the standard group needed 1.8.

Over the 3.26 years of follow-up, 5.2% of the intensive group and 6.8% of the standard group experienced a cardiovascular event. Intensive treatment led to a 25% lower risk of a cardiovascular event. The risk of death from cardiovascular events was 43% lower for those in the intensive group compared to the standard group. The risk of death from any cause was 27% lower in the intensive group.

Adverse (negative) events occurred in 38.3% of the intensive group and 37.1% of the standard group. Adverse events included low blood pressure, fainting, and acute kidney injury (sudden decrease in kidney function).

This study concluded that a target systolic blood pressure of 120 mmHg led to lower rates of cardiovascular events and death compared to the standard target of 140 mmHg.

This study did not include patients who had had a previous stroke or with diabetes mellitus, both important cardiovascular risk factors. It is not clear from these results if intensive blood pressure management would decrease risks in these patients.

Discuss appropriate blood pressure targets with your physician.