Should we be advising patients to take their antihypertensives at night?

I have read with great interest a research paper entitled ‘Bedtime hypertension treatment improves cardiovascular risk reduction: the Hygia Chronotherapy Trial’ published in the European Heart Journal by Hermida et al.¹

The trial randomly assigned 19 084 patients to either take their antihypertensives upon waking in the morning or at bedtime. The patients were subsequently followed up over a median period of 6.3 years with ambulatory 48-hour blood pressure monitoring done at inclusion and at least annually.

After adjusting for significant confounding variables such as sex, age, smoking history, type 2 diabetes, chronic kidney disease, previous and cardiovascular events, among others, the risk of cardiovascular death, myocardial infarction, coronary revascularisation, heart failure, or stroke nearly halved (6.5% vs. 11.9%).

National Institute for Health and Care Excellence advice on starting antihypertensive drug treatment was last updated prior to the publication of this research and does not recommend a time of day to give the medication.²

With the results seeming almost too good to be true — the New England Journal of Medicine (NEJM) Journal Watch, a sibling publication to the NEJM, reviewed the article. They made the point that ideally the trial would be replicated; however, given the significant difference in adverse outcome with morning dosing, they questioned whether it would be ethically sound to randomise patients to the morning dosing arm. Ultimately, they felt recommending that patients take once-daily antihypertensive drugs in the evening was reasonable.³

Nature Reviews Cardiology has also acknowledged that, while the mechanism is unclear, the time of dosing is important for blood pressure control and protection against cardiovascular disease.⁴

Given these findings, I’d encourage fellow clinicians to consider recommending patients to take their antihypertensives at night. The question is now whether future guidelines will take note of this trial and recommend night dosing of antihypertensives.

• © British Journal of General Practice 2022