Should i take my blood pressure in the morning or at night

One of the ways to diagnose high blood pressure is with a 24-hour blood pressure monitor.

In healthy people, nocturnal blood pressure dips by about 15% compared with daytime values.

Patients who don't have this blood pressure drop at night, often called non-dippers, are at increased risk for cardiovascular mortality, heart failure, and stroke.

This has led many researchers to consider the issue of chronotherapy — the idea that when you take a pill is as important as or possibly more important than which pill you take.

Most patients take their blood pressure medications in the morning. But blood pressure is supposed to decrease at night, and switching some blood pressure medication to bedtime rather than morning makes intuitive sense.

The Hygia Chronotherapy trial reported very large decreases in stroke, MI, and death with nighttime dosing of antihypertensives.

The results got a lot of media attention.

But commentators quickly pointed out problems with this study.

First, the magnitude of the benefit was extremely large for a very small change in blood pressure.

Even nighttime blood pressure measurements showed only small differences between both groups.

Meta-regression studies have suggested that even with a 10-point reduction in blood pressure, one should expect around 20% relative risk reduction in cardiovascular disease, stroke, and all-cause mortality.

But the Hygia trial suggested that cardiovascular disease was nearly cut in half for a much smaller decrease in BP.

Second, switching blood pressure medication from morning to nighttime administration reduced not just CVD death but also total death, ie, all-cause mortality.

Why the timing of blood pressure medications should affect non-cardiovascular mortality to such a large degree is unclear — and somewhat implausible.

Finally, important questions about medical therapy really need to be decided by well-conducted randomized trials. But critics have questioned whether the Hygia Chronotherapy trial was actually randomized.

They point out that the word "randomized" was used only three times in the entire manuscript: once to define the acronym PROBE and twice to refer to a previous study on the same subject by the same authors.

These critiques and subsequent inquiries led the editors of the European Heart Journal to publish an "expression of concern" about the study, and the issue seems to be under investigation.

For now, it's not clear whether the timing of blood pressure medication really affects clinical endpoints to any significant degree.

In studies such as HOPE and EUROPA, in which medications were given at night, researchers did observe a reduction in cardiovascular events, but they were testing a medication vs placebo, not evening vs morning doses.

In the CONVINCE trial, nighttime verapamil, a calcium channel blocker, did not improve outcomes compared with morning doses of hydrochlorothiazide or atenolol. But again, researchers were not comparing evening vs daytime doses of the same medication.

For now, there is insufficient evidence to be certain that nighttime dosing of medication has much benefit.

But given that 1 in 5 Americans with high blood pressure is unaware that they have it and is not receiving any treatment for this very modifiable risk factor, chronotherapy might be less important than whether patients get any therapy at all.

Christopher Labos is a cardiologist with a degree in epidemiology. He spends most of his time doing things that he doesn't get paid for, like research, teaching, podcasting, and writing for the newspaper. Occasionally he finds time to practice as a cardiologist so that he can pay his rent. He realizes that half of his research findings will be disproved in 5 years; he just doesn't know which half. He is a regular contributor to the Montreal Gazette, CJAD radio, and CTV television in Montreal. To date, no one has recognized him on the street or asked for his autograph.

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ANKARA, TURKEY - NOVEMBER 14: A woman takes a pill on November 14, 2018 in Ankara, Turkey. (Photo ... [+] by Dogukan Keskinkilic/Anadolu Agency/Getty Images)

If you have high blood pressure, remembering to take your medication is so important.

In fact, the time of day when you take your medicine could influence your risk for complications such as heart attack and stroke, which is ultimately related to how well you manage your blood pressure.

The body’s natural rhythm, known as the “circadian rhythm” also affects how we respond to specific medications, the result of a complex interplay between your medication and cortisol, the chief hormone responsible for this rhythm.

Now, a new study recommends that you take your blood pressure medicine at bedtime—to lower your blood pressure during the night and early morning—helping to prevent elevation of blood pressure that normally occurs as you awaken.

The research was published earlier this week in the European Heart Journal.

There is a growing body of evidence which indicates that not only genetics, but the time of day you take a medicine may influence how effective it is for treating a particular condition.

The current study looking at this phenomenon represents the largest study to date of patients with high blood pressure, and included more than 19,000 persons (from 40 ambulatory blood pressure monitoring clinics in Spain) on medications to treat high blood pressure.

For the study, the patients were randomly assigned to one of 2 groups: one group took their pills in the morning, and the other group took them at bedtime. The investigators monitored the patients for over 6 years tracking their blood pressure.

Blood pressure normally drops as we fall asleep, reaching its lowest between midnight and 3-4 am. It gradually rises as we awaken thanks to release of cortisol from the adrenal glands. Those who do not experience a drop in blood pressure during sleep may, in fact, be at higher risk for heart attack and stroke.

The study found that those who took their medication at bedtime had a significantly lower average blood pressure both at night and during the day, dipping more at night compared to those who took their medication during the morning or daytime.

Study participants who took their medicine at night were 43% less likely to experience any cardiovascular event (heart attack, stroke, heart failure) compared with those who took it in the morning. Those who took their medicine in the nighttime also had a 49% lower risk for stroke, 34% lower risk for heart attack, and 42% lower risk for developing heart failure.

Overall, there was a 45% reduction in cardiovascular risk from any cause (composite score of risk of heart attack, stroke, coronary artery bypass grafting [CABG] or cardiac stent placement, heart failure) in those who took blood pressure medication at bedtime. There was also a 56 % reduction in risk from cardiovascular disease overall.

The results of the study, demonstrating an impressive reduction in risk for heart attacks and strokes, argue for taking blood pressure medicine at bedtime. While previous research has also shown reduction in cardiovascular effects with night time administration of blood pressure medication, this is the largest study to date.

That said, more research is still necessary to better understand if the effect seen in patients taking a specific class of medication in this study also applies to different classes of blood pressure medications. (Study participants took a variety of blood pressure medications including ACE inhibitors, ARBs, ACEI- ARB combination, diuretics, calcium channel blockers, beta-blockers.)

Additional research is also necessary for different ethnicities, as well as those who work various late or overnight shifts to see if taking blood pressure medications in the late evening before bed has the same effect on reducing stroke and heart attacks

While blood pressure has multiple genetic determinants, lifestyle choices also have a significant impact. To reduce blood pressure, it’s best to reduce alcohol intake, quit smoking, lose weight, reduce stress, exercise more, reduce salt intake, practice yoga or Tai chi, and embrace deep abdominal or diaphragmatic breathing and meditation.

Health care providers recommend that patients try to adhere to a schedule and take their medications at the same time every day. Interestingly, current guidelines don’t provide any specific recommendation regarding timing for blood pressure medications, with many people choosing to take them in the morning.

If you take blood pressure medicine, your health care provider has indicated on your prescription when to take it. It’s best to consult with your provider and inquire why they have prescribed to take in the morning or before going to bed.

One issue is whether taking blood pressure medicine at night time is the best clinical approach for all patients. Age is certainly one determinant as well as fall risk, since a lower blood pressure at night and early morning can place patients at higher risk for falls, especially in a dark room when attempting to use the bathroom.

“Timing of blood pressure medicine is very patient-specific,” said Satjit Bhusri, M.D., FACC, Assistant Professor of Cardiology, Lenox Hill Hospital, Northwell Health. “There are many factors, including compliance, labile blood pressure, and other medications being administered at the same time.”

In conjunction with your healthcare provider, the desire to change the timing of blood pressure medication ultimately involves the ability to lower cardiovascular risk. To achieve lower blood pressure while asleep, it’s vital that patients take their medicine at the same time every night.

“The key here is routines,” said Bhusri. “An even routine has shown that patients are more compliant with taking their medications more regularly and not forgetting.”

While a nighttime approach may achieve a lower mean blood pressure while asleep, helping to reduce cardiovascular risk, is compliance or consistency also playing a role?

“The key play here is compliance of medication,” offered Bhusri. “Not missing a dose—we know one thing worse than an elevated blood pressure is swings in blood pressure due to periodic non-compliance.”

If further trials continue to demonstrate reductions in cardiovascular risk with the night time approach, the issue is whether all patients should take their meds at bedtime.

“This recommendation is a personalized one that should involve a joint physician-patient interchange,” concluded Bhusri.

The Skinny on Blood Pressure

It turns out that your blood pressure begins to rise as you wake up in the morning, elevates through midday, but then actually reaches its lowest point of the day between midnight and 3-4 am.

That said, persons with

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