Parkinson's Disease (PD) is a devastating disease that renders its victims unable to control their movement. Recent research has shed two important factors that can both help understand the onset and perhaps even stop the progression of the disease entirely.

A period known as the preclinical period - where the damage of the disease may be occurring but motor symptoms have not manifested yet - was always understood to occur around 6 years prior.  What was learned during a study performed by Rodolfo Savica and colleagues shows that the preclinical period may be as great as 20 years in advance of onset of motor symptoms. The indicators are not what one would look for or attribute to PD either,

Conditions such as constipation, anxiety disorders, rapid eye movement sleep behavior disorder (RBD) and anemia may be associated with the pre-clincal period of PD and may begin to occur as far out as 20 years prior to the onset of neuro-motor symptoms. Olfactory impairment and depression may also precede the onset of motor manifestations, but the lag time may be much shorter.

Recognition of non-motor symptoms may give clinicians better preclinical biomarkers when identifying the risk factors of PD.

What is more exciting however is that a study published in the Archives of Neurology has discovered  a link between vitamin D levels and the onset of PD. Paul Knekt and colleagues at the National Institute for Health and Welfare, Helsinki, Finland performed a longitudinal study over the course of 13 years with 3,373 men and women who were PD free at the onset of the study. Blood samples were drawn from 1978 through 1980 and frozen.

Over the 13 years 50 participants developed PD. The blood samples from all the participants was examined and a direct link between the lowest Vitamin D levels and the onset of PD was established. At the same time the individuals with the highest Vitamin D levels had a significantly reduced risk of developing the disease.

The results are consistent with the suggestion that high Vitamin D status provides protection against PD. The mechanism of action is unclear, however, we do know that there is a concentration of Vitamin D receptors in the Sunstantia Nigra and thus it may be that the activity and protection of dopamine producing neurons is some how linked to the availability of Vitamin D. More research is needed to better understand how Vitamin D influences the onset of PD.

In the mean time, if you believe that you have a risk of PD, it would be prudent to have your blood levels of Vitamin D tested regularly and supplement with Vitamin D to keep levels high.