Current guidance for first line treatment of hypertension – which differs depending on patient age and ethnicity – could be simplified in line with international recommendations, according to a study in The BMJ.
Research by the London School of Hygiene and Tropical Medicine found similar reductions in blood pressure for three major drug types in people of all ages and ethnicity.
They suggest that other factors might be considered to guide the choice of drug.
Excluding people with diabetes, current guidelines from the National Institute for Health and Care Excellence recommend:
Calcium channel blockers (CCB) for those aged 55 and older, and for people of Black African or African-Caribbean family ethnicity
Angiotensin converting enzyme inhibitors or angiotensin receptor blockers (ACEI/ARB) for non-Black people younger than 55
Age based recommendations are unique among major international guidelines for hypertension treatment, based on differences in the activity of the renin-angiotensin system with age.
However, the evidence base has moved on since the guidelines were developed in the early 2000s.
Review of Patient Records
To investigate further, the researchers reviewed UK primary care records of more than 150,000 new users of hypertension drugs between 1 January 2007 and 31 December 2017.
After adjusting for confounding factors, the researchers found similar reductions in blood pressure associated with both CCBs and ACEIs/ARBs in people aged above and below 55.
Further analysis suggested that CCBs were associated with greater reductions in blood pressure than ACEIs and ARBs, but only in people aged 75 and older.
Reductions in blood pressure appeared to be numerically greater for Black people without diabetes taking CCBs versus ACEIs and ARBs than those blood pressure reductions in non-Black people without diabetes, the study found. However, one limitation of the study was the relatively small number of Black people included.
The researchers said they were also unable to verify whether individual patients had adhered to treatment or not.
Nevertheless, the authors conclude: “Our results suggest that the current UK algorithmic approach to first line treatment for hypertension might not lead to greater reductions in blood pressure and could be simplified.
“Moving towards a choice of any of the three major hypertension drug classes with suggested compelling indications for their use would align the UK with international guidance, in particular with regard to age,” they add.
Commenting on the results, Prof Graham MacGregor, chair of Blood Pressure UK, said: “Most individuals require two drugs to get good control of their blood pressure and it makes sense to follow NICE guidelines on the right combinations. In these patients, it doesn’t matter which drug you start with, but the right combinations must be used.
“It is disappointing to see no discussion in the paper about the different mechanisms whereby these drugs work and the importance of salt intake. Furthermore, there is no reference to judging how much of the fall in blood pressure is due to the drug and the effect of repeated measurement.”
BMJ 2020; 371 doi: https://doi.org/10.1136/bmj.m4080 (Published 18 November 2020)