Blood pressure effects in frail older adults

Jane Masoli is an NIHR clinical doctoral fellow and Specialist Registrar in Geriatric Medicine at the College of Medicine and Health. She is currently working towards her PhD on blood pressure, co-morbidities and outcomes in older populations and, in this blog, she talks about her research into the link between low blood pressure and higher mortality rates and the publication of her paper in Age and Ageing Journal.

You can read the full paper here.

Blood pressure control

Tight blood pressure control clearly improves overall mortality in younger people. But does this apply to older people who may have several health conditions, frailty, dementia or nursing needs that would have excluded them from participation in the studies comprising the evidence base? Our data suggests that tight blood pressure control is not enough to alter their overall mortality.  

As a clinical doctor specialising in the care of older adults, I was aware of the discrepancy between patients recruited to randomised controlled trials, on which guidelines are based, and the majority of patients who we see clinically. Representative older adults are often excluded from participation in studies. Traditionally this was by age cut-offs, but this barrier has now been recognised and, more recently, relaxed or omitted from protocols. However, clinical trials often focus on single disease or risk factor management and exclude those with co-morbidity, frailty or cognitive or mobility limitations.  

There is clinical uncertainty regarding the prognosis of blood pressure in frail older adults. In this study we sought to test associations between baseline blood pressure and cardiovascular and mortality outcomes in a representative population of 415,980 older adults with primary and secondary care linked data from the Clinical Practice Research Datalink according to frailty status. We found that blood pressure (median over 3 previous years to reduce effect of acute illness) below 130/80 was associated with excess mortality in all adults over 75 whether frail or not. . Blood pressures over 150mmHg systolic were associated with increased cardiovascular outcomes with compared to 130-140, but without increased mortality in frail adults over 75 or all adults over 85. These findings are important as internationally there has been a move towards tight blood pressure targets, but we have shown that this may not be appropriate in frail older adults.   

Publishing a research study

The study described forms part of my PhD on blood pressure, co-morbidities and outcomes in older populations and is my third first-author publication from my thesis, with previous work on prognosis according to blood pressure in adults over 80 with hypertension[1] and older adults with Chronic Kidney Disease[2], building on our work on blood pressure trajectories[3] and multimorbidity[4]. I have been funded by the NIHR to take time out from my clinical training as a geriatrician to complete this PhD as a clinical doctoral fellow and prior to that worked as an Academic Clinical Fellow, combining clinical medicine with research training.  

Identifying the key journal for the research message is a key part of the publication process. Age and Ageing is the leading journal on ageing in the UK and is the International Journal of the British Geriatrics Society. I originally submitted the paper 3 months prior to publication, with a reviewers’ comments available 3 weeks later. This then required revisions in order to be suitable for publication, and the integration of reviewers’ comments was a useful addition to the paper, with the revised submission accepted for publication.

Having output from my PhD published in a peer-reviewed paper to an appropriate target audience aids dissemination of the scientific findings. More research is required in this area to ascertain whether aggressive blood pressure control is safe in older adults, and then for which patient groups there may be benefit, in order to move towards more personalised blood pressure management in older adults.  

1.          Delgado J,MasoliJAH, Bowman K et al. Outcomes of Treated Hypertension at Age 80 and Older: Cohort Analysis of 79,376 Individuals. J Am Geriatr Soc 2017; 65: 995–1003. 

2.          Masoli JAH, Delgado J, Bowman K, Strain WD, Henley W, Melzer D. Association of blood pressure with clinical outcomes in older adults with chronic kidney disease. Age Ageing 2019; 48: 380–387.

3.          Delgado J, Bowman K,BleA et al. Blood Pressure Trajectories in the 20 Years Before Death. JAMA Intern Med 2018; 178: 93. 

4.          Melzer D,TavakolyB, Winder RE et al. Much more medicine for the oldest old: trends in UK electronic clinical records. Age Ageing 2015; 44: 46–53.