Glucosamine and chondroitin sulphate (CS) are often used as over-the-counter medications to treat osteoarthritis. But how effective are these two chemicals really, or do patients just imagine that they feel better when they use them?
To answer this question, we need to look at a few aspects of this subject, for example: what osteoarthritis is, what studies have been done on glucosamine and CS, and what the results revealed.
What are glyconutrients?
Glucosamine and chondroitin sulphate are so-called glyconutrients that form part of healthy cartilage in the human body. These glyconutrients are also manufactured from shellfish shells and animal cartilage and are sold as nutritional supplements for the treatment of osteoarthritis.
What is osteoarthritis?
Osteoarthritis is a chronic condition that is characterised by a breakdown of cartilage tissue in the joints. In patients who suffer from osteoarthritis, the once-smooth cartilage tissue which cushioned the joints becomes rough, brittle and weak. Painful bone-to-bone friction usually occurs in the joints that are affected.
Patients with osteoarthritis suffer from joint pain, stiffness, thickening and inflammation. Osteoarthritis usually occurs in older people and is more prevalent in women. It is estimated that up to 20 million people in the USA, and 8 million in the UK, suffer from this often painful and debilitating disease.
How is osteoarthritis treated?
The standard medical treatment for osteoarthritis is the prescription of anti-inflammatories, particularly the group of medications called non-steroidal anti-inflammatory drugs (NSAIDS).
These drugs are, however, associated with a wide variety of side effects. Just in the past week, most South African newspapers featured articles with headings like "Painkillers raise risk of heart failure", which appeared in the Pretoria News on Wednesday.
Articles reported on the findings of a study which showed that 14% of patients admitted to hospital for heart failure for the first time were taking painkillers (usually for conditions like osteoarthritis), compared with 10% of healthy people.
In view of this most recent study on NSAIDs, alternative medications such as glucosamine and CS seem to be attractive options. But the crux of the matter is whether glucosamine and CS actually do the job of relieving the symptoms of osteoarthritis or not.
Quite a few studies have been carried out to verify if glucosamine and CS (individually and in combination) can alleviate osteoarthritis.
Some studies showed positive results, with patients experiencing less pain and greater mobility when using these medications. Other studies could not show that glucosamine and CS produce any improvements when compared to placebo (dummy treatment).
Recently, the US National Institutes of Health sponsored a large study called GAIT, using 1583 patients with osteoarthritis of the knee to compare the effects of glucosamine (1,5 g/day) alone, CS (1,2 g/day) alone, a combination of glucosamine and CS, orthodox medication (celecoxib) or placebo for 24 weeks.
The results of this study, which were published in the New England Journal of Medicine in February 2006, found that glucosamine and CS did not help to reduce pain any more than placebo and that only the orthodox medication (celecoxib) had true benefits.
Such results are of course disappointing to the public who were hoping that glucosamine and CS were the answer to their search for an osteoarthritis cure.
However, the latest edition of the Arbor Nutrition Updates, interpret the results of the above mentioned GAIT study in a much more positive light.
They point out "that in a sub-group of 354 patients with moderate to severe initial pain, those on glyconutrient combination scored better than those on celecoxib and were significantly more likely than placebo to have a positive response.." (Arbor, 2006).
The Arbor team, who are also highly respected scientists, concluded that "the weight of evidence is that these two glyconutrients are an effective and safe option for osteoarthritis, particularly for cases of at least moderate severity, and probably more so if the nutrients are taken together".
So, depending on how the latest research is interpreted, there does seem to be a role for the glyconutrients, glucosamine and CS, in the alleviation of the symptoms of osteoarthritis.
Do glyconutrients have side effects?
Because animal studies have found that glucosamine and CS may affect glucose metabolism and theoretically cause insulin resistance, there is some concern about their use as anti-arthritis medications.
However, there is no human evidence that their use affects glucose metabolism negatively. Nevertheless, it may be prudent for patients with diabetes to avoid the use of glyconutrients.
The authorities also caution that because glyconutrients have not been tested in elderly or pregnant women, these patients should not use them.
CS is also chemically related to drugs that thin the blood such as coumarin (warfarin), heparin and aspirin, and patients taking these drugs should not combine their use with intake of CS.
It is evident that some patients with osteoarthritis do respond positively to the use of glucosamine and CS.
If you suffer from osteoarthritis and do not have any other contraindications (pregnancy, diabetes or use of blood thinners), you can probably try using glyconutrients to alleviate the symptoms of your disease.
Experts agree that patients with osteoarthritis can do a number of things to reduce their symptoms:
- do resistance exercises to strengthen the muscles surrounding the painful joints;
- reduce your body weight to reduce the load on your joints;
- ask your doctor about medical or surgical options;
- use heat or ice treatment and physiotherapy to relieve pain;
- use topical creams to relieve painful joints;
- and remember, that prevention is better than cure, so keep your body weight as low as possible and do as much exercise as possible before you ever develop osteoarthritis.
- (Dr Ingrid van Heerden, DietDoc, updated June 2008)
(Arbor (2006). Arbor Clinical Nutrition Updates: Glyconutrients & osteoarthritis. 253; Robb-Nicholson C (2006). What can I do about osteoarthritis of the knee? Harvard Women's Health Watch. Pretoria News (2006) Painkillers raise risk of hear failure. Wednesday 24 May 2006 ).
Pain pills may harm heart
Joint Pain/Arthritis Centre