Why Does My Blood Pressure Go Up at Night?

Blood pressure varies in accordance with the circadian rhythm, with healthy individuals experiencing up to a 10-20% decrease in blood pressure at night. However, if your blood pressure goes up at night instead of decreasing, that can be alarming.

A medical expert of the American Heart Association says, “When you’re asleep at night, it’s the purest time for blood pressure. It’s a window into how that person’s system is working.” 

If you experience hypertension at night, there may be multiple reasons why it happens. High night-time blood pressure may be a sign of underlying medical conditions like diabetes or kidney diseases, but it may also be due to a high salt intake in your daily diet. 

We’ll get into more detail on the causes, but first, let’s cover the basics.

What Is High Blood Pressure (Hypertension)?

High blood pressure is a condition medically defined as hypertension, which is diagnosed when your blood pressure continuously remains too high. In a nutshell, when blood pressure is consistently too high, your heart has to work harder than usual. As a result, your arteries may lose their flexibility and may get damaged and clogged.

Before jumping to any assumptions, though, you need to know how to measure blood pressure.

How to Measure Blood Pressure

There is more than one way to measure blood pressure, but the gold standard method is known as ambulatory blood pressure monitoring.

In ambulatory blood pressure monitoring, your BP is recorded over 24 hours – even when you are asleep!

The blood pressure reading has two numbers and is measured in millimeters of mercury (mm Hg). The two numbers are as follows:

  • Systolic pressure (top number) denotes the pressure in your arteries as your heart beats.
  • Diastolic pressure (bottom number), on the other hand, is the pressure in your arteries between heartbeats.

According to the American Heart Association, American College of Cardiology, and several other prominent health organizations, normal blood pressure measurements should be at 120/80 mm Hg. Furthermore, blood pressure that’s considered elevated is at 120 mm Hg systolic and 80 mm Hg diastolic BP; stage 1 hypertension is in the range of 130-139/80-89 mm Hg; stage 2 hypertension is higher or equal to 140/90 mm Hg.

The Importance of Night-Time Monitoring

A third of adults in the United States have hypertension, as per the Center for Disease Control and Prevention

According to a recent study held at Jichi Medical University in Tochigi, Japan, “Night-time systolic blood pressure was a significant, independent risk factor for cardiovascular events.” While daily readings may come up as normal, abnormal night-time readings are just as telling when it comes to cardiovascular hazards.

Overall, nearly 20% of Americans don’t know that they have elevated BP or hypertension since they don’t monitor night-time blood pressure, so the risks of heart disease, heart attacks, strokes, heart failure, and more are that more prevalent. 

Causes of Elevated Night-Time Blood Pressure and Nocturnal Hypertension

Night-time blood pressure spikes are most frequently associated with underlying diseases. The three most commonly occurring ones are:

  • Diabetes mellitus
  • Chronic kidney disease (CKD)
  • Obstructive sleep apnea (OSA)

  However, there are other potential causes as well.

  • Hot temperature.
  • Sedentary lifestyle and/or lack of physical activity.
  • High salt intake (in relation to salt sensitivity).
  • Poor sleep quality and/or working shifts.
  • Obesity.
  • Stress.
  • Advancing age.
  • Family history of high blood pressure.
  • Excessive caffeine intake.

Furthermore, there are certain medications and supplements that can cause surges in blood pressure. Here are the most contentious ones, as per MayoClinic.org:

  • Pain and anti-inflammatory medications that may cause you to retain water, namely:
    • Indomethacin
    • Piroxicam
    • Ibuprofen, aspirin, and naproxen sodium
  • Decongestants such as:
    • Pseudoephedrine
    • Phenylephrine
  • Antidepressants like:
    • Monoamine oxidase inhibitors
    • Fluoxetine (Prozac)
    • Tricyclic antidepressants
  • Herbal supplements:
    • Arnica
    • Ephedra
    • Ginseng
    • Guarana
    • Licorice
  • Illegal drugs:
    • Amphetamines
    • Anabolic steroids
    • Cocaine
    • MDMA

How Do I Know if I Have Night-Time Hypertension?

You can determine having nighttime hypertension by monitoring your blood pressure levels at home. There are several types of BP monitors available. You can talk to your pharmacist or physician for suggestions for a blood pressure monitor that will suit your needs best. Having said that, here are two things to keep in mind when measuring your BP:

  • Make sure you are seated comfortably and your feet are flat on the floor when you check your BP;
  • You shouldn’t measure your blood pressure readings with a full bladder.   

How to Manage High Blood Pressure (Hypertension)?

Hypertension, including isolated nocturnal hypertension, is no joke. As always, you should consult your physician for accurate medical advice on how to treat any and all ailments, let alone diseases and conditions such as hypertension. Having said that, we could give you some general tips and sleep-related info that may help you with elevated night-time blood pressure.

Tips for Getting High BP in Control 

  • Be mindful of your salt intake.
  • Maintain a consistent sleeping pattern and improve your sleep quality by going to sleep and getting up at the same time every day.
  • Avoid consuming alcohol and caffeine before bedtime.
  • Sleep in a room with a regulated temperature.
  • Build an exercise routine.
  • Avoid stressful activities whenever possible and manage stressful events through therapy.
  • Use diuretics (if approved by a medical professional).

The Connection Between Sleep Quality and High Blood Pressure 

The average amount of sleep required for an adult is 7-8 hours. If you overlook your regular sleeping schedule and don’t get enough sleep, you’re at a higher risk of cardiovascular diseases. 

Sleep-related disorders such as insomnia, restless legs syndrome, obstructive sleep apnea, and such have been directly related to nocturnal blood pressure spikes. Furthermore, over the past 50 years, sleep duration has decreased by 2 hours a day, resulting in more than a third of Americans sleeping less than 6 hours a night. Consequently, consistently short sleep duration has been associated with a 60% increased risk of hypertension in adults under 60.

Longer sleep duration, on the other hand, has been associated with morning BP spikes.

Overall, since sleep duration is directly linked to sleep quality and sleep schedules (or lack thereof), we can safely surmise that having good sleep hygiene is imperative to maintaining cardiovascular health and mitigating hypertension.

The Best Sleeping Positions for High Blood Pressure 

The best sleeping position for people suffering from hypertensive conditions is on the left side. Sleeping on the left side relieves pressure on the blood vessels that bring blood back to the heart (the arteries).

FAQs:

Why Does My Blood Pressure Go Up When I Lay Down?

If your blood pressure goes up when you lay down, you may be suffering from a condition known as supine hypertension. Hypertension in the prone position affects your nervous system, which controls involuntary movements such as blood pressure. Drugs used for the treatment of orthostatic hypotension may worsen supine hypertension.

Is It Better to Take Your Blood Pressure Medications in the Morning or at Night?

Night-time blood pressure medications work better for patients who have non-dipping blood pressure, characterized by a reduction in night-time BP of less than 10%. However, your blood pressure medication regimens should be personalized.

Conclusion

Hypertension is called a silent killer because it often shows no symptoms. Preventing and even managing night-time high blood pressure is challenging, but it’s definitely doable. You can keep your blood pressure under control at night with some tweaks in your lifestyle, diet, and proper medications.

Do note that the information we provided is not professional medical advice. Please consult a medical professional for a proper diagnosis or therapy.