I suspect that high cholesterol levels can cause/accelerate some sorts of PD (vascular PD), but protect/slow other sorts of PD (IPD).

Unfortunately, the rate of misdiagnosis/non-diagnosis is probably such that many of us have insufficient data to be able to make an informed decision.

A Medical News Today article [1], reporting the work of Pinteaux et al., states:

"Neurodegeneration was also identified in the substantia nigra six days after the mild stroke - dopaminergic neurons had been destroyed."

Huang et. al. write [2]:

"Recent studies have suggested that higher serum cholesterol may be associated with lower occurrence of Parkinson's disease (PD). ... This secondary analysis of the DATATOP trial provides preliminary evidence that higher total serum cholesterol concentrations may be associated with a modest slower clinical progression of PD."

Finally, the decision of whether to take statins has got to take into account the wider health risks, e.g, strokes.

[1] http://www.medicalnewstoday.com/articles/254301.php

[2] Huang X, Auinger P, Eberly S, Oakes D, Schwarzschild M, et al. (2011) Serum Cholesterol and the Progression of Parkinson's Disease: Results from DATATOP. PLoS ONE 6(8): e22854. doi:10.1371/journal.pone.0022854
http://www.plosone.org/article/info%...l.pone.0022854

John