Scientists who study Parkinson's disease work not only to understand how the condition disables nerve cells but also how it impacts the daily lives of those who suffer from it. They are cautiously optimistic about a new study, published in the Archives of Neurology, which suggests that the dietary supplement coenzyme Q10 might help newly diagnosed Parkinson's patients preserve the nerve control they need to perform daily activities.

Testing a dietary supplement

Researchers from 10 US health facilities randomly assigned 80 men and women with early signs of Parkinson's disease (none were yet taking medication) to one of four treatment groups: coenzyme Q10 at a dose of 300 milligrams (mg), 600 mg, or 1200 mg a day, or an inactive pill (placebo). This was a double-blind study - neither the patient nor the physician knew which treatment group the patient was in. Physical and mental assessments were performed every 4 months during the 16-month study.

The researchers found that those who took coenzyme Q10 at a dose of 1200 mg daily fared better when compared with others in the study. These benefits were primary seen in a greater ability to perform 'activities of daily living', such as eating and getting dressed.

How it might work

Coenzyme Q is a naturally occurring substance in the mitochondria, the units within each cell responsible for producing energy. It seems to have two functions - it assists the energy-producing process within the cells, and it acts as an antioxidant, protecting the cells from free radical molecules (the potentially damaging by-products of normal cell functions).

Earlier studies have shown abnormally low levels of coenzyme Q10 in the blood cells of some Parkinson's patients and impaired cellular energy production in others. Those observations have led researchers to speculate that there might be a connection between low levels of coenzyme Q10, disrupted energy production within the cells, and the development of Parkinson's disease.

Advice to consumers

The authors of the study are encouraged by their results, but they warn both patients and healthcare providers not to read too much into these preliminary findings. This was a small study and all participants were in the early stages of Parkinson's; none yet required medication to manage the disease. And, say the authors, while the supplement appeared to have an effect on physical functioning, it is not yet clear if it actually helped prevent damage to nerve cells.

Plans are currently underway to expand the study to include a greater number of patients; this will give researchers a better picture of the circumstances in which coenzyme Q10 supplements might help people with Parkinson's.

Note: In the USA, coenzyme Q10 is marketed a dietary supplement. This means that coenzyme Q10-containing products do not come under the same level of scrutiny by governmental regulators as medications do. US consumers currently have no way to ensure that the dietary supplement they buy actually contains what its label says it contains, a particularly troubling problem when the supplement is being used as medication. As is always the case, patients should consult with their own healthcare provider before taking any dietary supplement.