This World Health Day on April 7,a slew of programmes will seek to raise awareness about hypertension. But in the din over the travails of high blood pressure and concomitant diseases such as diabetes,chronic low blood pressure has gone out of focus.
Low blood pressure without any symptoms,experts say,is not a cause for concern; it may,in fact,be a sign of health. Since there is a close link between a persons build and blood pressure,small people tend to have lower blood pressure. Indeed,pressure as low as 90/60 can be normal provided the person is able to go about her routine without problem.
Theories that linked low blood pressure with chronic malnutrition have been effectively junked,but the diagnosis continues to be a money spinner for physicians in small towns and major cities.
Low blood pressure is a myth created by doctors. Blood pressure as low as 90/60 can be considered normal provided there are no other related symptoms, says Dr D Prabhakaran,executive director of Centre for Chronic Disease Control.
The definition of normal blood pressure has seen a continuous downward revision over the years. In 1960s,160/95 was the upper limit of normal pressure in an adult but now even 115/75 is considered undesirable high blood pressure. This has effectively narrowed the low blood pressure band to a wafer,that too only if it is accompanied by other complaints.
It is only a sudden fall in blood pressure that may cause a person to lose consciousness or experience severe dizziness that can indicate an inherent pathological condition. There is a known phenomenon called orthostatic hypotension,where sudden postural changes are associated with a feeling of giddiness that may sometimes be a cause for concern. However,low pressure in most cases is no more than one of the symptoms of a range of conditions,from pregnancy to heart failure,erroneous heart beat rate to heat stroke. Besides,prescription medicines for high blood pressure,depression or Parkinsons can precipitate a bout of hypotension,as can hormonal conditions such as thyroid imbalance.
Fludrocortisone and such drugs are often used to raise blood volume and,therefore,blood pressure but mild or occasional dizziness is not considered serious enough to be treated,unless it recurs frequently. On the other hand,administering medicines that conserve salt or water in an otherwise normal individual can lead to stroke when the person is lying down because of a sudden spurt in blood pressure.
The concept of low blood pressure originated from the impression that there is a certain optimum level of BP
required to ensure blood flow to the brain. A frail person can function perfectly well with a lower than average blood pressure. However doctors in some cases continue to prescribe steroids or other drugs to raise blood volume which is a dangerous practice. We need to spread consciousness from medical colleges onwards on this, says Dr K S Reddy,president of the Public Health Foundation of India.