Low blood pressure - a forgotten disease?

In many countries low blood pressure is regarded as a sign of excellent health, and it is certainly true that it is associated with a good outlook from the point of view of risks of strokes an heart attacks. In others, such as Germany, It is regarded as a disease responsible for symptoms of weakness and fatigue. A survey of 254 healthy Irish bank workers has now looked to see how common it is in the general population. All the subjects wore a 24- hour blood pressure recorder, which obtained readings every 30 minutes throughout the day and night. It was decided to define low blood pressure as the lowest 5 per cent of all the blood pressure readings. This gave levels of 115/70 mm Hg for daytime readings in men, and 105/65 in women (women generally have lower pressures than men). Corresponding nighttime values were 97/56 in men and 92/52 in women.
In both genders, episodes of at least two consecutive readings of low blood pressure (that is below the limits described above) during the day were common, occurring in 59% of women and 43% of men. By definition, 5% of each gender had average levels below the limits. Women with low blood pressure tended to be shorter and to weight less than women with higher pressures, but there was no connection between body size and low blood pressure in then men.
Doctor’s comments
The purpose of this study was not to see if people with low blood pressure have symptoms, but merely to learn how common episodes of low pressure are in the general population. The main finding is that approximately 50% of healthy people have episodes lasting one hour at least where the pressure may be considered “low”, and that the phenomenon is commoner in women than in men. Obviously, the definition of what is meant by “low” is arbitrary, and this result emphasizes the normal variability of blood pressure that occurs in all of us.
Other studies have suggested that low blood pressure may be associated with fatigue, weakness, and depression. There may be overlap with the “chronic fatigue syndrome”, which remains poorly defined, and we do not know if it is the low pressure that is actually responsible for any of these symptoms.
Where it was published
Posted by Naz Blood Donors & Public Welfare Organization