Exploring Cardiovascular Autonomic Function before and after Chronic Deep Brain Stimulation in Parkinson's Disease

Area of Science:

• Neurology
• Cardiovascular Physiology
• Neurosurgery

Background:

• Parkinson's disease (PD) management involves complex blood pressure regulation.
• Autonomic dysfunction and levodopa treatment significantly impact blood pressure in PD patients undergoing subthalamic deep brain stimulation (STN-DBS).

Purpose of the Study:

• To investigate the effects of chronic STN-DBS, levodopa, and their combination on cardiovascular autonomic functions in Parkinson's disease patients.

Main Methods:

• Cardiovascular reflex tests (CRTs) were conducted on 20 PD patients pre- and 6-months post-STN-DBS surgery.
• CRTs were performed both without medication (med-OFF) and with medication (med-ON).

Main Results:

• No significant differences in CRT results or neurogenic orthostatic hypotension (OH) were observed between pre- and post-STN-DBS in the med-OFF state.
• Levodopa intake led to a significantly greater blood pressure decrease during HUTT (head-up tilt test) compared to med-OFF, both pre- and post-STN-DBS.
• Levodopa-induced OH incidence decreased from 25% pre-STN-DBS to 5% post-STN-DBS in the med-ON condition.

Conclusions:

• Chronic STN-DBS does not appear to influence cardiovascular autonomic responses in PD patients.
• Levodopa significantly impacts blood pressure, causing a hypotensive effect.
• STN-DBS surgery is associated with a reduced occurrence of levodopa-induced orthostatic hypotension.