Figure 2. Kaplan-Meier survival curves.

Subjects with Pittsburgh compound B (PiB) retention above the median for the sample converted to a more severe diagnosis sooner than those with values below the median. Parkinson disease with normal cognition and Parkinson disease with mild cognitive impairment groups were pooled together for this analysis. Shading around survival curves indicates 95% confidence bands. “Censored” indicates the last visit for subjects who had not transitioned to a more severe diagnosis.