Why “low blood pressure,” a dangerous and life-threatening condition, is on the rise in Japan: Fainting, myocardial ischemia, and impaired renal function.

The misconception that low blood pressure is better

During a live broadcast of the noon information program “Miyaneya” (NTV), attorney Masataka Kamei, who appeared as a regular commentator, became slurring his words and was unable to respond to the MC’s calls for help, so he left the show. Tension ran high in the studio. The cause, it was later revealed, was “low blood pressure.

Low blood pressure is often taken lightly as a physical ailment that can be cured with a little rest, but the medical community sees it quite differently.

Dr. Yoshimasa Gotoh, director of the Gorakai Clinic Shirokane-Takanawa, says, “Low blood pressure is a dangerous condition that causes insufficient blood flow to the brain, heart, and kidneys. It can lead to fainting, falls, and in the worst case, even death,” he warns (hereafter, “” denotes Dr. Gotoh).

In general, people tend to think that high blood pressure is dangerous and low blood pressure is good. In recent years, from the viewpoint of preventive medicine, there has been a growing trend toward stricter control of blood pressure. In clinical practice, however, it is not uncommon for blood pressure to drop too low, necessitating emergency treatment.

If it is transient,” says Dr. Kohara, “the patient may only feel dizzy or fatigued. However, if hypotension persists, it can lead to serious consequences such as fainting spells, bone fractures, myocardial ischemia, and impaired renal function. Especially in the elderly, fractures can lead to bedridden conditions.”

Blood pressure is the pressure that delivers blood to organs throughout the body. If it drops too low, it can affect life support itself. Why are more and more people suffering from low blood pressure nowadays?　There are three major factors.

(1) Multiple use of antihypertensive drugs

In recent years, the target for hypertension treatment has been increasingly set at less than 130/80 mmHg. Although effective in preventing stroke and myocardial infarction, the drugs may be too effective for the elderly, thin people, and those with impaired renal function.

Dr. Goto continued.

Elderly people have less supple blood vessels and less ability to pump blood to the organs. Therefore, even with an upper blood pressure of 110 mmHg or 100 mmHg, some people may not receive enough oxygen and nutrients to the brain, kidneys, and muscles. Just looking at the numbers does not mean that you can rest easy.”

Chronic dehydration

In older people, it is harder to feel thirst. When this is combined with dryness in the room, sweating, loss of appetite, and diuretics, the amount of body fluid decreases without the person being aware of it. This reduces the amount of blood circulating and makes it easier for blood pressure to drop. Dehydration occurs not only in summer, but also in spring and winter. It is too late to drink water after becoming thirsty.

(iii) Decreased function of the autonomic nervous system

People with a long history of diabetes, Parkinson’s disease, and long-term bedridden patients (long-term bedridden patients, for example, who are hospitalized for a long period of time) are more likely to suffer from autonomic nervous system dysfunction. People with Parkinson’s disease and those who have been lying in bed for a long period of time (e.g., hospitalization) have a weakened regulatory function to maintain blood pressure at the moment of standing up. As a result, orthostatic hypotension is more likely to occur.

The accidental falls that occur immediately after waking up in the morning or at the moment of standing up to use the toilet are not uncommon.

It is not uncommon for elderly people to suffer from postprandial hypotension, in which blood flows to the gastrointestinal tract after eating, causing a drop in blood pressure throughout the body. Strong drowsiness or lightheadedness after eating is a sign to watch out for.

A Dangerous Combination

In recent years, hypertension treatment has focused on suppressing the “morning surge,” a rapid rise in blood pressure in the early morning. The sympathetic nervous system becomes active before and after waking up, a time when cerebral and myocardial infarctions are more likely to occur.

It is important to suppress early morning blood pressure surges. However, if the blood pressure drops too low during the day or at night, this can be a problem.

As a result of blood pressure falling too low, patients experience lightheadedness during the day, drowsiness after eating, falls during the night when using the restroom, and dizziness at dawn.

Modern hypertension treatment is a tightrope walk between wanting to lower blood pressure in the morning and not wanting to lower it too much at night.

The mainstream treatment is a combination of ARBs (drugs that lower blood pressure by suppressing the action of hormones that constrict blood vessels), Ca channel blockers (drugs that lower blood pressure by widening blood vessels), diuretics (drugs that lower blood pressure by producing excess water and salt), and other medications.

For patients with heart failure or chronic kidney disease, an SGLT2 inhibitor (a drug that releases sugar and water into the urine to protect the heart and kidneys) and an MRA (a drug that suppresses the action of hormones that cause the body to store salt and water to reduce the burden on the heart and blood vessels) may be added to this combination.

The risk is that the multiple effects of these medications may cause blood pressure to drop all at once. In particular, diuretics plus SGLT2 inhibitors plus sweating on extremely hot days should be treated with caution.”

Do not assume that the following symptoms are simply fatigue

Dizziness on standing up
Cold sweats
White or narrowed vision
Strong drowsiness after eating
Feeling like you are going to collapse the moment you wake up in the morning
Feeling of consciousness fading away.

It is sometimes difficult to distinguish it from hypoglycemia or arrhythmia. If you have experienced even one near-fainting episode, please see a doctor as soon as possible.”

Dr. Goto recommends the following basic preventive measures.

Measure blood pressure within an hour after waking and before going to bed.
If the upper blood pressure stays below 100 mmHg for a long period of time, consult a doctor.
Drink water frequently (1.2 to 1.5 liters per day).
Do not stand up suddenly.
Do not move for 30 minutes to 1 hour after eating.
Avoid extreme low-sodium and low-nutritional intake.

Many people blame their age for their poor health, such as being tired easily, having a hard time in the morning, or feeling sleepy after eating. However, dangerous low blood pressure may be lurking in the background.

Dr. Goto concludes by saying, “People are concerned only about high blood pressure.

People are concerned only about high blood pressure, but too low blood pressure is also dangerous. I would like you to take a look at your blood pressure, especially if you are taking medication or if you are elderly.

Blood pressure is not only too high, but also too low. This common sense is likely to become more and more important in Japan in the future.