Friday 21 August 2015

What are natural treatments for strokes?


Introduction


Strokes occur when part of the brain suddenly loses its
blood supply and dies. The underlying cause is generally atherosclerosis, a condition in which the walls of blood
vessels become thickened and irregular. As atherosclerosis progresses, blood flow
through important arteries becomes restricted to a much smaller passage than is
normal. This narrow passage can then suddenly become blocked, often by a blood
clot. When this happens, brain cells downstream of the blockage are suddenly
deprived of oxygen (cerebral ischemia). Brain cells require a constant supply of
oxygen to survive. Within seconds, they begin to malfunction, and within minutes
they die.




In what are called transient ischemic attacks (TIAs), the
blockage to blood flow is temporary, and symptoms rapidly disappear. However, in a
true stroke, called a cerebral vascular accident (CVA), the blockage lasts long
enough to cause cell death in a significant section of the brain. Less commonly,
strokes are caused by bleeding into the brain, which is known as a hemorrhagic
stroke.


The symptoms of a stroke depend on the area of the brain affected. Paralysis of
one limb or one side of the face is common. Loss of speech or sensation may also
occur. Much of the loss that occurs in a stroke is permanent, but some recovery
usually does occur in time. There are two main causes of this recovery. The first
involves the body’s ability to grow new blood vessels. Nerve cells on the margins
of the dead area may cling to survival, functioning imperfectly on whatever oxygen
drifts to them. Eventually, new blood vessel growth enables the nerve cells to
recover perfectly.


The second cause of recovery involves the brain’s remarkable ability to adapt to
difficult circumstances: To a lesser or greater extent, surviving parts of the
brain can take over tasks once performed by brain cells that have died.


Conventional treatment for a stroke has several phases, but the most important is
prevention. Stopping smoking, losing weight, reducing cholesterol levels, and
controlling blood pressure prevent atherosclerosis and thereby reduce the risk of
stroke. Also, physicians may recommend the use of blood-thinning drugs, such as
aspirin, to prevent the blood clots that so frequently are the final step to a
stroke. Furthermore, if there is evidence that the main blood vessels leading to
the brain are seriously narrowed, surgery or angioplasty
may be considered to widen those vessels.


Treatment of a stroke that has just occurred involves maintaining life during the
immediate recovery period and limiting the spread of brain damage (if possible).
Finally, physical and occupational therapists help the stroke survivor to
adapt.




Principal Proposed Natural Treatments

There are a number of alternative options that may be useful for preventing or even possibly treating strokes. The best documented are those that fight atherosclerosis.



Stroke prevention. Meaningful evidence indicates that numerous herbs and supplements are helpful for improving the cholesterol profile, which in turn should decrease atherosclerosis and help prevent strokes. Weaker evidence supports the use of other herbs and supplements for lowering blood pressure or for treating atherosclerosis in general.



Policosanol. Various herbs and supplements with blood-thinning
properties have been suggested for use instead of or with aspirin to prevent blood
clots. The best evidence regards the supplement policosanol.


Several double-blind, placebo-controlled trials indicate policosanol significantly reduces the blood’s tendency to clot. In one such study of forty-three people, the use of policosanol at 20 milligrams (mg) per day proved approximately as effective as 100 mg of aspirin; in addition, when the two treatments were taken in combination, the effect was greater than with either treatment alone. Furthermore, this supplement appears to reduce cholesterol levels, making it potentially an all-around stroke-preventing treatment. However, while the long-term use of aspirin has been shown to reduce stroke risk, no equivalent studies of policosanol have been done. In addition, combined treatment with policosanol and aspirin (or related drugs) could conceivably thin the blood too much, resulting in dangerous bleeding events.



Stroke treatment. Cells at the margin of a stroke may cling to
life until new blood vessels form to supply them with full circulation. Certain
herbs and supplements might facilitate this by increasing blood flow or,
alternatively, by reducing brain-cell oxygen requirements. Although the evidence
remains preliminary, two supplements have shown some promise for this purpose:
vinpocetine and glycine.



Vinpocetine. In a single-blind, placebo-controlled trial, thirty
persons who had just experienced a stroke received either placebo or
vinpocetine with conventional treatment for thirty days.
Three months later, evaluation showed that participants in the vinpocetine group
were significantly less disabled.


A few other studies, some of poor design, also provide suggestive evidence that vinpocetine may be helpful for strokes. However, this body of evidence remains far from conclusive. A review combining two relatively high-quality studies involving sixty-three persons could not determine whether or not vinpocetine provided any benefit for persons who had a stroke. Also, there are concerns that vinpocetine could interact harmfully with standard drugs used to thin the blood.



Glycine. The supplement glycine also
has been proposed as a treatment for limiting permanent stroke damage. However,
the supporting evidence is largely limited to one moderate-sized Russian trial. In
this double-blind, placebo-controlled study, two hundred people received glycine
within six hours of an acute stroke. The results indicate that the use of glycine
at 1 gram daily for five days led to less long-term disability than placebo
treatment.


However, paradoxically, there are potential concerns that high-dose glycine could actually increase harm caused by strokes, and drugs that block glycine have been investigated as treatments to limit stroke damage. The authors of the Russian study on strokes made an argument that the overall effect of supplemental glycine is protective; nonetheless, until this controversy is settled, one should not take glycine following a stroke except on a physician’s advice.




Other Proposed Natural Treatments

Evidence suggests that high consumption of fish or fish oil
reduces stroke incidence. This is believed to occur as a result of a number of
effects, including impairment of blood clots, improvement of cholesterol profile,
and other unidentified means.


Many other herbs and supplements may also reduce the blood’s tendency to clot and, thereby, help prevent strokes. These herbs and supplements include bilberry, feverfew, garlic, ginger, ginkgo, quercetin, vitamin E, and white willow. However, the supporting evidence for these supplements remains weak at best, and the mere fact that they thin the blood does not prove that they will reduce stroke risk. For example, while vitamin E is known to reduce blood clotting and is also a strong antioxidant, several large studies have failed to find vitamin E helpful for stroke prevention.


Similarly, the herb white willow has been advocated as a
substitute for aspirin because it contains salicin, a substance very much like
aspirin. However, willow, taken in usual doses, does not appear to impair blood
coagulation to the same extent as aspirin, and for that reason, it is probably not
equally effective. The supplement folate has shown some promise for
preventing strokes. Also, besides vitamin E, other antioxidants, such as
beta-carotene, have been proposed for stroke prevention, but there is no evidence
that they are effective.



Acupuncture is widely used in China for enhancing recovery
from strokes. However, while some studies have suggested benefits, the
best-designed and largest studies have not been promising. For example, in a
single-blind, placebo-controlled trial of 104 people who had just experienced
strokes, ten weeks of twice-weekly acupuncture did not prove more effective than
fake acupuncture. Similarly negative results were seen in a single-blind,
controlled study of 150 people recovering from stroke, which compared acupuncture
(including electro-acupuncture), high-intensity muscle stimulation, and sham
treatment. All participants received twenty treatments in a ten-week period.
Neither acupuncture nor muscle stimulation produced any benefits. In addition, a
ten-week study of 106 people, which provided a total of thirty-five traditional
acupuncture sessions to each participant, also failed to find benefit. Finally,
ninety-two persons who randomly received either twelve acupuncture treatments or
comparable sham treatment for four weeks demonstrated the same level of
improvement up to one year later. The few studies that did report improvements
from acupuncture were small, and some did not use a placebo group. In a review of
fifty-six trials (mostly written in Chinese), researchers found that 80 percent
showed positive results. However, the small size and variable quality of these
studies make it difficult to draw reliable conclusions about the benefits of
acupuncture in the setting of a stroke. In one study, acupressure combined with
lavender, rosemary, and peppermint aromatherapy was more effective than
acupressure alone for treating the shoulder pain caused by hemiplegic strokes.
However, this study lacked a proper placebo group and therefore means little. A
review of nine trials found limited evidence in support of moxibustion (the
application of heat to acupuncture points) in addition to standard care for stroke
rehabilitation. Also, the semisynthetic substance citicholine (closely related to
the nutrient choline) has shown some promise for aiding recovery from strokes.


In a study investigating the effects of music therapy, stroke patients who
listened to music of their own choosing in the early stages of their recovery
demonstrated more improvement in memory and attention than those patients who
listened to language (that is, books on tape). Music listeners were also less
depressed and confused than subjects who listened neither to music nor to
language.




Herbs and Supplements to Use with Caution

If one is at risk for a stroke, it might be advisable to avoid excessive intake of iron. Some evidence suggests that high iron levels may increase stroke risk and worsen strokes that do occur.


People susceptible to stroke should exercise great caution regarding the herb
ephedra. Ephedra contains ephedrine, a
drug that raises blood pressure and stimulates the heart, and it has caused heart
attacks and strokes. Certain preparations of ephedra may present an additional
risk beyond ephedrine’s effects on the circulatory system: direct toxicity to
nerves.


Finally, numerous herbs and supplements may interact adversely with drugs used to prevent or treat strokes, so persons should be cautious when considering the use of herbs and supplements.




Bibliography


Bereczki, D., and I. Fekete. “Vinpocetine for Acute Ischaemic Stroke.” Cochrane Database of Systematic Reviews (2008): CD000480. Available through EBSCO DynaMed Systematic Literature Surveillance at http://www.ebscohost.com/dynamed.



Hopwood, V., et al. “Evaluating the Efficacy of Acupuncture in Defined Aspects of Stroke Recovery.” Journal of Neurology 255 (2008): 858-866.



Iso, H., et al. “Intake of Fish and Omega-3 Fatty Acids and Risk of Stroke in Women.” Journal of the American Medical Association 285 (2001): 304-312.



Lee, M. S., B. C. Shin, and J. I. Kim. “Moxibustion for Stroke Rehabilitation.” Stroke 41 (2010): 817-820.



Sarkamo, T., et al. “Music Listening Enhances Cognitive Recovery and Mood After Middle Cerebral Artery Stroke.” Brain 131 (2008): 866-876.



Shin, B. C., and M. S. Lee. “Effects of Aromatherapy Acupressure on Hemiplegic Shoulder Pain and Motor Power in Stroke Patients.” Journal of Alternative and Complementary Medicine 13 (2007): 247-252.



Wang, X., et al. “Efficacy of Folic Acid Supplementation in Stroke Prevention.” The Lancet 369 (2007): 1876-1882.



Wayne, P. M., et al. “Acupuncture for Upper-Extremity Rehabilitation in Chronic Stroke.” Archives of Physical Medicine and Rehabilitation 86 (2005): 2248-2255.



Wu, P., et al. “Acupuncture in Poststroke Rehabilitation.” Stroke 41 (2010): e171-179.

1 comment:

How can a 0.5 molal solution be less concentrated than a 0.5 molar solution?

The answer lies in the units being used. "Molar" refers to molarity, a unit of measurement that describes how many moles of a solu...