Lewy Body Dementia

OBJECTIVE: Lewy body dementia (LBD) is an umbrella term describing two closely related conditions: Parkinson disease dementia (PDD) and dementia with Lewy bodies (DLB). LBD is the second most common cause of neurodegenerative dementia but is often underrecognized in clinical practice. This review covers the key epidemiologic, clinical, cognitive, behavioral, and biomarker features of LBD and discusses current treatment options. LATEST DEVELOPMENTS: Indicative biomarkers of LBD improve the ability to make a diagnosis and include single-photon emission computed tomography (SPECT) of the dopamine system (brain) and the noradrenergic system (cardiac), and polysomnography. α-Synuclein-specific biomarkers in spinal fluid, skin, plasma, and brain imaging are in active development with some available for clinical use. Prodromal stages of PDD and DLB have been contextualized, and diagnostic criteria have been published. An emerging theme is whether an integrated staging system focusing on protein aggregation, rather than clinical symptoms, may advance research efforts. ESSENTIAL POINTS: LBD is a common cause of cognitive impairment in older adults but is often subject to significant delays in diagnosis and treatment, increasing the burden on patients and family care partners. Understanding key features of disease and the use of biomarkers will improve recognition. Earlier detection may also facilitate the development of new therapeutics and enrollment in clinical trials.