The investigators searched the AZSAND database for patients who presented from January 1997 through December 2015. They identified 641 autopsies. Clinical data and information on Lewy-type synucleinopathy were available for 280 of the cases. The population included cases with Lewy bodies and those with synuclein pathology within the neuropil and fibers. The population’s mean age at death was 83. Greater severity of synucleinopathy was associated with younger age at death.
Braak Staging Could Not Characterize Some Patients
The researchers classified 8.6% of cases as Stage I, 15.4% as Stage IIa, 13.6% as Stage IIb, 31.8% as Stage III, and 30.7% as Stage IV. Cognition was normal in 25.7% of the cases, 8.6% had mild cognitive impairment, and 65.7% had dementia.
Multiple measures of motor parkinsonism and cognitive impairment, as well as of hyposmia and probable REM sleep behavior disorder, correlated significantly with increasing USSLB stage. A few clinical features had no correlation with USSLB stage.
Dr. Adler and colleagues also applied the Braak staging criteria to the cases. To classify all cases, the investigators added an olfactory-bulb-only stage to the Braak criteria. Of the initial cohort, 70 cases could not be assigned a Braak stage. When the researchers removed cases with Alzheimer’s disease, 21% of cases could not be staged.
—Erik Greb