Abnormal Cerebrovascular Activity, Perfusion, and Glymphatic Clearance in Lewy Body Diseases.

Cerebrovascular activity is not only crucial to optimal cerebral perfusion, but also plays an important role in the glymphatic clearance of interstitial waste, including α-synuclein. This highlights a need to evaluate how cerebrovascular activity is altered in Lewy body diseases. This review begins by discussing how vascular risk factors and cardiovascular autonomic dysfunction may serve as upstream or direct influences on cerebrovascular activity. We then discuss how patients with Lewy body disease exhibit reduced and delayed cerebrovascular activity, hypoperfusion, and reductions in measures used to capture cerebrospinal fluid flow, suggestive of a reduced capacity for glymphatic clearance. Given the lack of an existing framework, we propose a model by which these processes may foster α-synuclein aggregation and neuroinflammation. Importantly, this review highlights several avenues for future research that may lead to treatments early in the disease course, prior to neurodegeneration. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Relationships between obstructive sleep apnea and anxiety.

PURPOSE OF REVIEW: To summarize recent research investigating the interaction between obstructive sleep apnea (OSA) and anxiety, and contextualize their bidirectional relationship. RECENT FINDINGS: Recent investigations corroborate the bidirectional relationship between sleep-disordered breathing (SDB) and anxiety, evaluate the etiological and clinical manifestations through different mechanisms, and provide insight into clinical implications of this interaction. Much of the literature about anxiety as it relates to SDB is from small samples, using different tools of symptom measurement that are often subjectively quantified. The objective severity of OSA does not appear to be associated with subjectively reported sleepiness and fatigue, whereas physiological manifestations of anxiety are associated with the severity of subjective symptoms reported. Recent findings support that women are more likely to have comorbid SDB and anxiety than men. SDB may precipitate and perpetuate anxiety, whereas anxiety in OSA negatively impacts quality-of-life. Treating SDB may improve anxiety symptoms, whereas anxiety symptoms can be an obstacle and deterrent to appropriate treatment. SUMMARY: The interaction between anxiety and SDB is still poorly elucidated. Being aware of the clinical associations, risk factors, and treatment implications for SDB as related to anxiety disorders in different populations can help clinicians with the diagnosis and management of both SDB and anxiety.