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Low blood pressure linked to depression
GALVESTON, TEXAS. Excessively low blood pressure has long been
considered a disorder in continental Europe and has been treated with
many remedies and medications ranging from coffee and cold showers to
ephedrine and amphetamine. In the United States and the United Kingdom,
on the other hand, the prevailing wisdom is that the lower the blood
pressure the better.
This assumption may now be about to change following a ground-breaking
study carried out by researchers at the University of Texas Medical
Branch. The researchers studied 2723 Mexican Americans aged 65 years or
older. Participants were interviewed to determine their level of
depression and fatigue as well as their self-reported health status and
degree of self-esteem. They also had their blood pressure measured at
two separate occasions. Seven hundred and seventy-eight (29.7 per cent)
of the study participants had a low diastolic pressure (i.e. below 75 mm
Hg), 428 (15.9 per cent) had a low systolic pressure (i.e. below 120 mm
Hg, and 265 (9.9 per cent) had both diastolic and systolic hypotension.
The researchers found that participants with hypotension were more
likely to be depressed, had lower self-esteem and global self-reported
health, and were more likely to wake up tired in the morning than were
participants with blood pressures in the normal range (systolic pressure
between 120 and 139 mm Hg and diastolic pressure between 75 and 84 mm
Hg). The low blood pressure correlation with depression, etc. was
independent of whether the low blood pressure was inherent or caused by
the use of blood pressure lowering medications (antihypertensives).
Participants with both low diastolic and low systolic pressures were
almost 2.5 times more likely to be significantly depressed than were
participants with normal blood pressures.
The researchers conclude that there is a definite association between
low blood pressure and depression and warn that over-treatment of high
blood pressure (hypertension) could conceivably result in
depression.
Stroup-Benham, Christine A., et al. Relationship between low blood
pressure and depressive symptomatology in older people. Journal of the
American Geriatrics Society, Vol. 48, March 2000, pp. 250-55
Robbins, Michael A., et al. Low blood pressure and depression:
comorbidity and competing outcomes. Journal of the American Geriatrics
Society, Vol. 48, March 2000, pp. 336-37 (editorial)
Not all sodium salts cause increased blood pressure
SAN FRANCISCO, CALIFORNIA. An experiment was carried out to determine
if administration by ingestion of extra sodium chloride (240 mmol of
sodium per day) would increase blood pressure in 5 males who suffered
from hypertension. The blood pressure of the participants had been kept
in the normal range prior to the experiment through restriction of
dietary sodium intake to 10 mmol/day (0.23 g of sodium). The average
systolic pressure went from 126+-4 mm Hg to 142+-4 mm Hg and the average
diastolic pressure went from 76+-2 mm Hg to 84+-4 mm Hg after about 3
days of consuming the extra salt (5.5 g/day) in the form of capsules.
Changing the content of the capsules to dextrose (placebo) or sodium
citrate (240 mmol of sodium/day) reversed the increase caused by the
sodium chloride. Thus it would appear, from this limited experiment,
that not all sodium salts cause an increase in blood pressure and that
the chloride ion may play an important role. Administration of extra
sodium chloride increased plasma volume and calcium excretion whereas
extra intake of sodium citrate did not. Both salts induced comparable
sodium retention, weight gain, and suppression of plasma renin activity
and plasma aldosterone.
Kurtz, Theodore W., et al. "Salt-sensitive" essential hypertension in
men. The New England Journal of Medicine, Vol. 317, No. 17, October 29,
1988, pp. 1043-48
Smokeless tobacco (oral snuff or chewing tobacco) can lead to high
blood pressure in regular users
SAN FRANCISCO, CALIFORNIA. A study of eight healthy men showed that
sodium absorption (measured by urinary excretion) from smokeless tobacco
was substantial, averaging 137 and 152 mmol/day for snuff and chewing
tobacco respectively as opposed to 107 mmol/day from regular cigarettes.
An extra sodium load of this magnitude could increase blood pressure by
5 to 10 mm Hg.
Benowtiz, Neal L. Sodium intake from smokeless tobacco. The New
England Journal of Medicine, Vol. 319, No. 13, September 29, 1988, pp.
873-74
Obesity and alcohol may cause hypertension
OAKLAND, CALIFORNIA. A study of 1031 subjects who developed
hypertension over a six year period was carried out to determine the
possible effects of obesity, weight gain, alcohol usage, and salt
consumption on the development of "essential" hypertension. The results
from this group were compared with the results from a matched group of
1031 normotensive subjects. Obesity and weight gain were shown to be
clear precursors of hypertension. Excessive alcohol consumption also
related to the development of hypertension, most significantly on a
short-term basis. A family history of hypertension was found to be
significant on a mother-daughter basis, but not on a paternal basis.
The results concerning the effect of salt intake were
inconclusive.
Friedman, Gary D., et al. Precursors of essential hypertension: body
weight, alcohol and salt use, and parental history of hypertension.
Preventive Medicine, Vol. 17, No. 4, July 1988, pp. 387-400
Hold the licorice
SAN FRANCISCO, CALIFORNIA. The regular consumption of licorice candies
(based on licorice root extract) can result in high blood pressure,
sodium and water retention, and excessive loss of potassium. A 70-year
old man was admitted to the San Francisco General Hospital because of
weakness, mental slowness, and significant weight loss. It was found
that he had been eating 25-40 licorice candies a day for four to five
years. Some of his symptoms persisted for four months after he stopped
eating licorice. Other studies confirm the detrimental effects of
continuous licorice consumption.
Farese, Robert V., et al. Licorice-induced hypermineralocorticoidism.
The New England Journal of Medicine, Vol. 325, No. 17, October 24, 1991,
pp. 1223-27
Anxiety may cause hypertension
BIRMINGHAM, ALABAMA. Many people believe that anxiety and repression of
anger can lead to hypertension (high blood pressure). Now medical
doctors involved in the Framingham Heart Study have confirmed that a
high level of anxiety can indeed cause future hypertension. Their 20-
year study involved 497 men and 626 women with normal blood pressure
(average 130/78) at the start of the study. The participants were
divided according to age, one group being between 45 and 59 and one
group between 60 and 77 years of age at the beginning of the study. The
men in the 45-59 year age group were found to have twice the risk of
developing hypertension (blood pressure >160/95) over the next 20 years
if they had a high baseline measure of anxiety compared to men with a
low anxiety level. This was independent of their age, initial systolic
blood pressure, heart rate, weight, alcohol consumption, glucose
tolerance, smoking status, and educational level. Feelings of anger,
whether expressed or suppressed, were not significantly correlated with
the later development of hypertension. The researchers did not find any
correlation between tension level and later hypertension in women or men
over 60 years. This is surprising as another recent study did find a
relationship between anxiety level and later hypertension in middle-aged
women working outside the home.
Markovitz, Jerome H., et al. Psychological predictors of hypertension
in the Framingham Study. Journal of the American Medical Association,
Vol. 270, No. 20, November 24, 1993, pp. 2439-43
Uric acid implicated in heart disease
NEW ORLEANS, LOUISIANA. Excessive uric acid concentrations in the blood
may result in gout and arthritis. Now evidence is mounting that uric
acid may also be implicated in hypertension, heart disease, obesity,
diabetes, and high cholesterol levels. Uric acid is the end product of
purine metabolism and earlier studies have shown that its concentration
in the blood is inversely related to blood flow through the kidneys.
There is also evidence that uric acid concentration in the blood tends
to increase with age and that the accompanying decrease in blood flow
through the kidneys is a definite risk factor for coronary heart
disease. NOTE: Coffee, tea, meat, and chocolate all contain purine-
forming compounds.
Frohlich, Edward D. Uric acid - a risk factor for coronary heart
disease. Journal of the American Medical Association, Vol. 270, No. 3,
July 21, 1993, pp. 378-79
Blood pressure may predict heart attacks
SAN FRANCISCO, CALIFORNIA. At a recent meeting of the American Heart
Association Dr. Sverre E. Kjeldsen from the University of Oslo presented
data to the effect that blood pressure during exercise is a potent
indicator of the risk of heart attack. The study involved 1999 healthy
men between 40 and 59 years of age at time of enrollment. Dr. Kjeldsen
found the men who had a systolic blood pressure of 200 mm Hg or greater
during exercise (on a stationary bicycle) had almost twice the risk of
experiencing a heart attack than did men with a resting systolic
pressure of less than 140 and an exercise pressure of less than 200.
The seriousness of the heart attacks among the men with high blood
pressures was also greater with 58 per cent of them being fatal as
compared to 33 per cent for the other men. Dr. Kjeldsen speculates that
a bicycle ergometer or treadmill test can be used to determine the risk
of heart attack for mildly hypertensive patients.
BP rise during exercise: a simple predictor of heart attack?
Geriatrics, Vol. 48, No. 11, November 1993, p. 26
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