The Parkinson’s/Statin Paradox: New Analysis Raises Questions About Previous Findings

In 2013, a paper published in Neurology advocated a clinical opinion that statin use was protective against Parkinson’s disease (PD).¹ However, Xuemei Huang, MD, PhD, professor and vice chair for research, Penn State Neurology, led a team in a prospective analysis of the connection between statins and PD in the Atherosclerosis Risk in Communities (ARIC) study, which strongly suggests the opposite finding.²

While the analysis was based on just 106 cases of the more than 15,000 patients enrolled in ARIC, Huang says, “The length of the study, measurement of cholesterol, and recording of patients’ statin history all combine to make top-notch data collection.” One especially interesting feature of the ARIC patient cohort is that the study began before statins were widely used, but continued for twenty years, marking a unique opportunity to analyze pre- and post-statin disease correlates. In addition, not only did Huang’s study find that statins may not confer a protective effect against the development of PD, but they may actually increase the risk of developing PD with long-term use.²

It is not yet fully understood why this inverse association exists. One theory is that the neuroprotective effect of the coenzyme Q10 is negatively affected by the use of statins, as statins reduce the biosynthesis of coenzyme Q10, as well as cholesterol.² To further extrapolate from this theory, it is possible that elevated cholesterol levels, which drive statin use, may be associated with a lower risk of PD.² Anecdotal clinical evidence is consistent with this hypothesis—statins can induce both myopathy and encephalopathy, suggesting adverse effects in both the peripheral and central nervous systems.²

Huang concludes, “I hope that our study can plant a seed among clinicians to evaluate statin usage in a more balanced way. Evidence shows that statins play an important role in preventing cardiovascular disease, but what is good for the heart may not be good for the brain. Our study suggests that lowering cholesterol unnecessarily actually may harm the brain.” Huang believes statins are not a cure-all, but rather a potentially valuable treatment option when all risk factors, not just cardiovascular risk factors, are evaluated on a case-by-case basis.

References

1. Lee Y-C, Lin C-H, Wu R-M, Lin M-S, Lin J-W, Chang C-H et al. Discontinuation of statin therapy associates with Parkinson disease. Neurology July 30, 2013;81;5:410-416.
2. Huang X, Alonso A, Guo X, Umbach DM, Lichtenstein ML, Ballantyne CM et al. Statins, Plasma Cholesterol, and Risk of Parkinson’s Disease: A Prospective Study. Mov Disord January 14 2015;1-8.