Introduction
Sickle cell
disease is an inherited blood disorder. Normally, red blood
cells are disc-shaped and flexible. In sickle cell disease, however,
hemoglobin (the chemical within red blood cells that carries
oxygen around the body) is abnormal. This defect causes red blood cells to
collapse into a crescent, or sickle, shape.
These abnormal blood cells are destroyed at an unusually high rate, causing a
shortage of red blood cells (anemia). In addition, they can suddenly
clump together and clog up small blood vessels throughout the body. This clumping
causes what is called a sickle cell crisis. When blood vessels are blocked by
sickle-shaped red blood cells, parts of the body are deprived of oxygen. This can
cause severe pain and damage to the organs and tissues that are deprived.
Sickle Cell Disease
The red blood cells are sickle-shaped rather than round, which causes blockage of
capillaries.
The common triggers of sickle cell crisis include smoking, exercise, exposure to
high altitudes, fever, infection, dehydration, and the drop in oxygen and changes
in air pressure that can occur during air travel. Diagnosis of sickle cell disease
and sickle cell trait (a condition in which a person has one of the two genes
necessary to develop sickle cell disease) can be done through blood testing, using
a technique called hemoglobin electrophoresis.
Treatment involves managing the anemia, chronic pain, and organ damage caused by
sickle cell disease. In addition, the drug hydroxyurea can reduce occurrences of
sickle cell crisis. It is also important to minimize exposure to conditions or
situations that can trigger sickle cell crisis.
Principal Proposed Natural Treatments
Children with sickle cell disease often do not grow normally. Zinc deficiency can
also cause growth retardation, and there is some evidence that people with sickle
cell disease are more likely than others to be deficient in the mineral zinc. For
this reason, zinc supplementation at nutritional doses has been suggested
for children with sickle cell disease.
In a placebo-controlled study, forty-two children (aged four to ten years) with sickle cell disease were given either zinc supplements (10 milligrams [mg] of zinc daily) or placebo for one year. Results showed that by the end of the study, the participants given zinc showed enhanced growth compared to those given placebo. Curiously, researchers did not find any solid connection between the severity of zinc deficiency and the extent of response to treatment.
Zinc is thought to have a stabilizing effect on the cell membrane of red blood cells in people with sickle cell disease. For this reason, it has been tried as an aid for preventing sickle cell crisis. In a double-blind, placebo-controlled study of 145 people with sickle cell disease conducted in India, participants received either placebo or about 50 mg of zinc three times daily. During eighteen months of treatment, the zinc-treated subjects had an average of 2.5 crises, compared to 5.3 crises for the placebo group. However, zinc did not seem to reduce the severity of a crisis, as measured by the number of days spent in the hospital for each crisis.
Sickle cell disease can also cause skin ulcers (nonhealing sores). In a twelve-week, placebo-controlled trial, the use of zinc at 88 mg three times per day enhanced the rate of ulcer healing. In another placebo-controlled trial, 25 mg of zinc three times per day for three months reduced the frequency of infections in children with sickle cell disease.
The high dosages of zinc used in the last two studies can cause dangerous toxicity and should be taken only under the supervision of a doctor. The nutritional dose described in the first study, however, is safe.
Other Proposed Natural Treatments
A year-long, double-blind, placebo-controlled, crossover study of eighty-two
people with sickle cell disease tested a combination herbal treatment made from
plants indigenous to Nigeria. The results indicate that the use of the herbal
mixture reduced the incidence of sickle cell crisis. A small, double-blind,
placebo-controlled trial found intriguing evidence that fish oil may
reduce the frequency of painful sickle cell episodes, possibly by reducing the
tendency of the blood to clot.
Also suggested for people with sickle cell disease are numerous other herbs and supplements, including alpha-linolenic acid, beta-carotene, coenzyme Q10, folate, garlic, green tea, lipoic acid, magnesium, oligomeric proanthocyanidins, suma, and vitamins B2, B6, B12, C, and E, but the supporting evidence for these treatments remains far too preliminary to be relied upon.
Bibliography
Ballas, S. K. “Hydration of Sickle Erythrocytes Using a Herbal Extract (Pfaffia paniculata) In Vitro.” British Journal of Haematology 111 (2000): 359-362.
Bao, B., et al. “Zinc Supplementation Decreases Oxidative Stress, Incidence of Infection, and Generation of Inflammatory Cytokines in Sickle Cell Disease Patients.” Transl Res. 152 (2008): 67-80.
Ohnishi, S. T., T. Ohnishi, and G. B. Ogunmola. “Sickle Cell Anemia: A Potential Nutritional Approach for a Molecular Disease.” Nutrition 16 (2000): 330-338.
Tomer, A., et al. “Reduction of Pain Episodes and Prothrombotic Activity in Sickle Cell Disease by Dietary N-3 Fatty Acids.” Thrombosis and Haemostasis 85 (2001): 966-974.
Zemel, B. S., et al. “Effect of Zinc Supplementation on Growth and Body Composition in Children with Sickle Cell Disease.” American Journal of Clinical Nutrition 75 (2002): 300-307.
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