Blood pressure: downward trajectory shown in decade before death

By Nicole MacKee
Older people experience a downward trajectory in blood pressure in the 10 to 14 years before death, researchers have reported in JAMA Internal Medicine.

In their population-based study of 46,634 UK participants who died at age 60 years or older, the researchers determined that systolic and diastolic blood pressure peaked at 18 to 14 years before death, and then progressively declined. They found that mean changes in systolic blood pressure (SBP) from peak values ranged from -8.5 mmHg for those dying aged 60 to 69 years, to -22.0 mmHg for those dying at 90 years or older. Overall, they found that SBP dropped by more than 10 mmHg in 64% of study participants. 

A downward trend in SBP was identified in participants not taking antihypertensive medications, but the steepest falls were in those with treated hypertension, dementia, heart failure and late-life weight loss. 

The researchers said these findings may have implications for treatment monitoring, and decreases in blood pressure may also bias risk estimation and complicate trial design. 

Professor Mark Nelson, Chair of the Discipline of General Practice at the University of Tasmania, said the downward trajectory identified in the study was an interesting new finding. 

‘We have noted that blood pressure variability tends to increase as we get older and closer to death, and we know that diastolic blood pressure tends to peak at around age 55 and drop away. But the natural thing we [usually] see in population studies is a gradual rise in systolic blood pressure,’ said Professor Nelson, who is also Clinical Liaison at the High Blood Pressure Research Council of Australia. 

He noted that the trajectories to death did not seem to be influenced by age. ‘The [downward trend] is linked to whatever your trajectory is to death, and this is not only from cardiovascular causes, it will be cancer, Parkinson’s [disease] and all the diseases associated with ageing,’ he said. ‘But what you do notice from the study is that in the older cohorts the starting blood pressures are higher, which is consistent with the general trend of blood pressures increasing as you get older.’

Professor Nelson said the findings reinforced the importance of taking a holistic approach to healthy ageing. 

‘We need to look at environmental factors that may be causing these people’s vital signs to deteriorate, their blood pressure to go down, their weight to go down, their muscle volume to decrease,’ Professor Nelson said. 

‘It may be inevitable [that these patients are on a trajectory to death]. It may be a sign that that particular person with their genetics and their environmental exposure is reaching their use-by date. But I am not a fatalist, I think these findings prompt us to look at more holistic approaches to healthy ageing.’ 
JAMA Intern Med 2017; doi: 10.1001/jamainternmed.2017.7023.

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