LOS ANGELES—The Unified Staging System for Lewy Body Disorders (USSLB) enables the categorization of almost all brains with Lewy body synucleinopathy, according to research described at the 70th Annual Meeting of the American Academy of Neurology. The USSLB’s stages correlate significantly with motor and nonmotor findings. “Wider use of the USSLB would help standardize research in synucleinopathies,” said Charles H. Adler, MD, PhD, Professor of Neurology at Mayo Clinic in Scottsdale, Arizona.
Investigators have developed several neuropathologic staging systems for Lewy body disorders, but many focus on specific diseases, such as Parkinson’s disease or dementia with Lewy bodies. They thus do not allow the classification of all patients with Lewy body disorders. In addition, the literature contains few data about how well these systems’ stages correlate with clinical and pathologic findings.
The Emergence of the USSLB
Dr. Adler and colleagues proposed the USSLB in research published in Acta Neuropathologica in 2009. Their goal was to enable the classification of patients with Lewy body disorders, regardless of their specific diagnoses. The USSLB includes four stages. Stage I denotes pathology limited to the olfactory bulb. Stage IIa denotes predominantly brainstem involvement. Stage IIb refers to pathology predominantly in the limbic system, rather than the brainstem. Stage III denotes pathology in the brainstem and limbic system. Stage IV represents neocortical pathology.
To examine the correlation between patients’ motor and nonmotor findings, including cognitive measures, and the extent of Lewy-type synucleinopathy, as categorized by the USSLB, Dr. Adler and others examined data from the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND). That study includes participants in the Banner Sun Health Research Institute brain and body donation program. Participants undergo annual clinical exams that include movement testing, cognitive testing, sleep and autonomic questionnaires, and a smell test.