Article type: Literature Review
Article title: Cardiovascular dysautonomia and cognitive impairment in Parkinson's disease (Review)
Journal: Medicine International
Year: 2024
Authors: Ibrahim Khalil, Reem Sayad, Ahmed M. Kedwany, Hager Hamdy Sayed, Ana Letícia Fornari Caprara, and Jamir Pitton Rissardo
E-mail: jamirrissardo@gmail.com
ABSTRACT
Cognitive impairment is a prevalent non‑motor symptom of Parkinson's disease (PD), which can result in significant disability and distress for patients and caregivers. There is a marked variation in the timing, characteristics and rate at which cognitive decline occurs in patients with PD. This decline can vary from normal cognition to mild cognitive impairment and dementia. Cognitive impairment is associated with several pathophysiological mechanisms, including the accumulation of β‑amyloid and tau in the brain, oxidative stress and neuroinflammation. Cardiovascular autonomic dysfunctions are commonly observed in patients with PD. These dysfunctions play a role in the progression of cognitive impairment, the incidents of falls and even in mortality. The majority of symptoms of dysautonomia arise from changes in the peripheral autonomic nervous system, including both the sympathetic and parasympathetic nervous systems. Cardiovascular changes, including orthostatic hypotension, supine hypertension and abnormal nocturnal blood pressure (BP), can occur in both the early and advanced stages of PD. These changes tend to increase as the disease advances. The present review aimed to describe the cognitive changes in the setting of cardiovascular dysautonomia and to discuss strategies through which these changes can be modified and managed. It is a multifactorial process usually involving decreased blood flow to the brain, resulting in the development of cerebral ischemic lesions, an increased presence of abnormal white matter signals in the brain, and a potential influence on the process of neurodegeneration in PD. Another possible explanation is this association being independent observations of PD progression. Patients with clinical symptoms of dysautonomia should undergo 24‑h ambulatory BP monitoring, as they are frequently subtle and underdiagnosed.
Keywords: orthostatic hypotension, supine hypertension, dysautonomia, cognitive impairment, dementia, mild cognitive impairment, PD, non‑motor symptoms, cardiac MIBG
Full text available at:
DOI
Citation
Khalil I, Sayad R, Kedwany AM, Sayed HH, Caprara A, Rissardo JP. Cardiovascular dysautonomia and cognitive impairment in Parkinson's disease (Review). Med Int 2024;4:70.
Figure 1. Summary of the non‑motor symptoms of PD. The main non‑motor symptoms are neurobehavioral features, sleep disorders, autonomic dysfunction and sensory impairments. Anxiety and depression are common neuropsychiatric symptoms in PD, occurring from the early pre‑motor phase to the advanced stages of the disease. By contrast, cognitive decline and dementia are typically regarded as a part of late‑stage PD. Autonomic dysfunction is a frequent occurrence in PD and can occur before the appearance of motor symptoms, and as the disease advances, the prevalence is increased. PD, Parkinson's disease.
Figure 2. Pathophysiology of autonomic dysfunction and cognitive impairment in PD. WMHs are associated with diastolic OH and partially explain the impact of autonomic dysregulation on cognitive loss in patients with PD. Autonomic dysfunction in the initial stages of clinical development makes the brain more susceptible to WMHs by disrupting blood flow in the small blood capillaries. SH can result in kidney damage, which in turn causes pressure diuresis and aggravates OH. Therefore, a cycle leading to the development of cognitive abnormalities can be noticed. PD, Parkinson's disease; WMHs, white matter hyperintensities; OH, orthostatic hypotension; SH, supine hypertension.
Figure 3. Management of OH. After diagnosing the case as an OH, there are three steps that should be followed to manage the case. Pharmacological simplification should be considered by reducing or terminating medications that exacerbate nOH. Subsequently, the non‑pharmacological measures should be started before using medications to treat nOH. Finally, pharmacological treatment is still needed in many cases to alleviate symptomatic nOH. OH, orthostatic hypotension; nOH, neuxrogenic orthostatic hypotension.
Table I. Summary of different patterns of BP dysregulation associated with PD.
Table II. Comparison between PD and dementia with Lewy bodies.
Table III. Cognitive impairment and OH in the elderly.
Table IV. Summary of pharmacological treatment of nOH and SH.
Table V. Summary of pharmacological treatment of cognitive impairment in PD.