Lithium's effects on serum neurofilament light in Parkinson's disease.

BackgroundBlood neurofilament light (NfL) is a disease-progression biomarker in Parkinsons disease (PD). ObjectivesTo determine the effects of lithium therapy on serum NfL in PD. MethodsFrozen serum samples from 28 PD patients were assessed for serum NfL using the SIMOA platform at baseline and after 24-weeks of lithium therapy. Pairwise comparisons were performed using the Fisher-Pitman permutation test. ResultsMedian % changes in serum NfL were -12.8, -2.0 and 11.2 in three patient groups defined by serum lithium levels at week 24: "high lithium" (0.21-0.56mmol/L, n=10), "medium lithium" (0.14-0.20mmol/L, n=8) and "low lithium" (<0.10-0.12mmol/L, n=10), respectively. Pairwise group comparisons showed significant differences between high and low lithium (p=0.0001) and high and medium lithium (p=0.0203) but not medium and low lithium groups (p=0.0907). ConclusionsLithium therapy achieving serum levels 0.21-0.56mmol/L significantly reduced serum NfL in PD, which strongly supports further clinical investigation of lithiums potential disease-modifying effects in PD. Financial DisclosureThomas Guttuso, Jr. is the President and majority owner of e3 Pharmaceuticals, Inc., which manufactures a lithium aspartate dietary supplement. None of the other authors have any financial disclosures. Study FundingThis study was funded by the National Center for Advancing Translational Sciences of the National Institutes of Health under award number UL1TR001412 to the University at Buffalo.