As 2023 closes, we want to highlight an important paper published in early 2022. This work quantified the increase in risk of having an aortic dissection due to high blood pressure.
Doctors and people with aortic disease have long known that high blood pressure increases the risk of an AD, but to date there has been limited hard data. Current national guidelines variously recommend 130/80 for Thoracic Aortic Aneurysms (ACC/AHA – ref (1) – this also states that 120/80 may be of benefit) and 120/80 in long-term follow-up (ESC – ref (2)).
The new data is specifically oriented to aortic dissection and indicates that the risk of AD increases from as low as 110/75. It shows that existing hypertension guidelines (such as NICE – ref (3)) based on primary prevention of heart attack or stroke using 135/85 to 140/90 (stage 1 hypertension) or 160/100 (stage 2 hypertension) confer a considerably elevated risk of dissection.
Makoto Hibino and team (involving institutions in Toronto, Japan, London, Oslo and Stockholm) performed a very large study on over ½ million individuals from the Japanese Health Check-up Study, another more than 500,000 individuals from the UK Biobank, plus a meta-analysis involving a total of 4.5 million individuals.
The results show that the risk of dissection:
- increases by a factor of around 3 for “hypertensive individuals” in general
- increases by around 30 to 40% for each 20 mm Hg* increase in systolic BP (the upper figure)
- increases by around 65 to 80% for each 10 mm Hg increase in diastolic pressure (the lower figure).
It is now clear that the blood pressure of those with aortic disease must be managed differently from standard guidance based on heart attack or stroke prevention and that the target blood pressure should be in the region of ‘low normal’.
The Circulation Editorial, commenting on Hibino’s paper states: “…the key message is a wake-up call for the medical community not only to understand the exponential relationship between intravascular tension and the risk of dissection but also to adjust blood pressure probably to the lowest tolerated level.“
For the Circulation Editorial see Taming Hypertension to Prevent Aortic Dissection: Universal Recognition of a “New Normal” Blood Pressure?, Neinaber & Yuan, Circulation. 2022;145:645–647. DOI: 10.1161/CIRCULATIONAHA.121.058133
For the full paper see Blood Pressure, Hypertension, and the Risk of Aortic Dissection Incidence and Mortality, Hibino et al, Circulation. 2022;145:633–644. DOI: 10.1161/CIRCULATIONAHA.121.056546
(1) 2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease, JACC 2022, https://doi.org/10.1016/j.jacc.2022.08.004
(2) Acute aortic syndromes: diagnosis and management, an update – European Heart Journal (2018) 39, 739–749. doi:10.1093/eurheartj/ehx319
(3) Hypertension in adults: diagnosis and management NICE guideline NG136, 18th March 2022 https://www.nice.org.uk/guidance/NG136
* mm Hg – the standard ‘millimetres of mercury’ unit used for BP