Frail older people may not benefit from the same tight blood pressure control that has been shown to benefit relatively younger, healthier groups in existing trials.
The medical records of more than 400,000 patients in primary care were reviewed. The researchers found that lower than normal blood pressures were associated with a higher death rate among older people, particularly those over the age of 85 or those who were very frail.
These findings are in line with the most recent 2019 NICE guidelines which recommend a higher blood pressure target, of 150mmHg, in people aged 80 years or more. However, there are no clear targets for the blood pressure management in frail older people.
This research in itself will not change practice. But it highlights the difficulty of managing blood pressure in elderly frail patients. It is an important basis for further research that could improve healthcare providers' ability to provide more personalised treatment plans for older patients.
What’s the issue?
High blood pressure is the most common disease among the over 75s. But there is a lack of research into the impact of treatment in frail older people. They are often under-represented in clinical trials because of other illnesses they have, treatments they are taking, limited life expectancy or dementia.
Healthcare professionals aim to control high blood pressure in older people to reduce the risk of heart attack and stroke. Recent NICE guidelines suggest a systolic blood pressure target of under 140mmHg for those under 80 years, with a higher target of 150mmHg for those aged 80+. But existing evidence does not support clear targets for those aged 75 years and older. Some international guidelines have suggested lower blood pressure targets for all.
More than 400,000 electronic health care records were analysed to find a link between blood pressure and incidences of heart attacks, heart failure, strokes or death in people over 75. The analysis considered different levels of frailty in older people.
In line with previous research, this study found that higher blood pressure (systolic blood pressure over 150mmHg) was associated with a higher risk of experiencing heart attack, heart failure, or stroke. However, the researchers also found that:
- systolic blood pressure over 140mmHg was associated with a lower risk of death, particularly among the frail or those over 85
- systolic blood pressure below 130mmHg and diastolic blood pressure below 80mmHg was associated with an increased risk of death
These results suggest that higher blood pressure does not necessarily mean a higher risk of death in older, frail people.
Why is this important?
Many healthcare professionals prioritise the reduction of blood pressure in older people with hypertension. An influential trial found that in older adults, a target of 120 mmHg reduced heart attacks, heart failure, stroke and deaths compared with the higher target of 140mmHg. But, like most blood pressure trials, it did not include people with dementia or frailty.
The new results suggest frailty and age should be considered when deciding on the aim of blood pressure treatment. They suggest that reducing blood pressure to less than 130mmHg may not be appropriate for frail people or those over 75.
These findings are an important consideration in the move towards more personalised medicine as the number of older people in our population continues to grow.
The results go against received wisdom on the treatment of the most common disease in older people and the implications are significant. Therefore further research needs to be done to back up these findings.
The study did not look at cause of death or at the impact other common diseases such as type 2 diabetes and kidney disease could have on mortality rates. Trials on the benefits and risks of changing the target blood pressure in this group are essential before the findings can inform practice.
Blood pressure in older people is complex, as is researching frailty, and any further study needs to account for this.
You may be interested to read
The full paper: Masoli J, and others. Blood pressure in frail older adults: associations with cardiovascular outcomes and all-cause mortality. Age and Ageing 2020;00:1-7
National Institute for Clinical Excellence (NICE) guidelines 2019: Hypertension in adults: diagnosis and management.
Delgado J, and others. Blood Pressure Trajectories in the 20 Years Before Death. JAMA Internal Medicine 2018;178: 93-99.
Masoli J, and others. Association of blood pressure with clinical outcomes in older adults with chronic kidney disease. Age and Ageing 2019. 48: 380-387.
Study author Jane Masoli is funded by an NIHR Doctoral Research Fellowship.