low Blood Pressure
Low blood pressure is the medical term for low blood pressure (less than 90/60).
Blood pressure reading appears as double digits. The first and highest of the two is the measurement of systolic pressure, or pressure in the arteries when the heart beats and fills with blood. The second figure measures diastolic pressure, or pressure in the arteries when the heart settles between the blows.
Optimal blood pressure is less than 120/80 (systolic/diastolic). In healthy people, low blood pressure without any symptoms is not usually a concern and does not require treatment. But low blood pressure can be a sign of an underlying problem – especially in the elderly – as it can cause insufficient blood flow to the heart, brain and other vital organs.
Chronic, symptomatic hypotension is never serious. But health problems can occur when blood pressure suddenly drops and deprives the brain of adequate blood supply. This can lead to dizziness. Sudden reductions in blood pressure occur commonly in a person who rises from lying down or sitting down to stand up. This type of low blood pressure is known as positional hypotension or erectile hypotension. Another type of low blood pressure can occur when someone stands for a long period of time. This is called low blood pressure. When it leads to fainting, if it is called Vasovagal syncope .
Positive hypotension is a failure of the heart, blood vessels or nervous system to respond appropriately to sudden changes. Usually, when standing, blood gathers in the lower extremities which lowers blood pressure. But your body is usually compensated by sending messages to your heart to pulse faster and to blood vessels to narrow them down. This compensates for low blood pressure. If this does not happen, or occurs very slowly, it results in low positive blood pressure and can lead to fainting.
The risk of low and high blood pressure usually increases with age due in part to natural changes during aging. In addition, blood flow to the heart muscle and brain decreases with age, often as a result of plaque buildup in blood vessels. It is estimated that 10% to 20% of people over the age of 65 suffer from positive blood pressure.
What causes low blood pressure?
The cause of low blood pressure is not always clear. It may be associated with:
- Pregnancy
- Hormonal problems such as hypothyroidism, diabetes or low blood sugar
- Some over-the-counter medications
- Some prescribed medications such as high blood pressure, depression or Parkinson’s disease
- Heart Attacks
- Arrhythmia (abnormal heart rhythms)
- Dilation or aneurysm
- Heat exhaustion or sunstroke
- Liver disease
What causes a sudden drop in blood pressure?
Sudden reductions in blood pressure can be life-threatening. The causes of this type of low blood pressure include:
- Blood loss from bleeding
- Low body temperature
- Overheating body
- Heart muscle diseases that cause heart failure
- Sepsis (severe blood infection)
- Severe dehydration caused by vomiting, diarrhea or fever
- Reaction to medication or alcohol
- Severe allergic reaction called anaphylaxis that causes arrhythmias
Who has positive hypotension?
Positive hypotension, which is low blood pressure when standing suddenly, can occur to anyone for a variety of reasons, such as dehydration, food shortages or excessive fatigue. It can also be affected by genetic formation, aging, medications, dietary and psychological factors and acute stimuli, such as infection and allergies.
Positive blood pressure drops occur most often in people taking medications to control high blood pressure. It can also be associated with pregnancy, strong emotions, atherosclerosis or diabetes. Older people are particularly affected, especially those with high blood pressure or an imbalance in the autonomic nervous system.
Low blood pressure is a common cause of dizziness, especially after eating. This is more common after large meals that contain a lot of carbohydrates. It is believed to be caused by blood aggregation in the stomach and intestines.
Many medications are usually associated with positive hypotension. These drugs can be divided into two main categories:
- Medications used to treat hypertension, such as diuretics, beta blockers, calcium channel blockers and angiotensin-converting enzyme inhibitors (ACE).
- Medications that contain low blood pressure as a side effect, including nitrates, erectile dysfunction medications, Parkinson’s disease medications, antipsychotics, anti-anxiety agents, sedative hypnotics, and tricyclic antidepressants
Common causes of normal postural hypotension include:
- Dehydration that may result from diarrhea, vomiting and excessive blood loss during menstruation or other conditions
- Age-related decrease in blood pressure regulation, which may be exacerbated by certain health conditions or medications
Some diseases can also cause positive blood pressure. These include:
- Central nervous system disorders, such as Shy-Drager syndrome or multiple system atrophy
- Nerve problems, such as peripheral neuropathy or autonomic neuropathy
- Heart and vascular disorders
- Alcoholism
- Nutritional Diseases