Effects of Deep Brain Stimulation on Autonomic Symptoms in Parkinson's Disease: A Scoping Review

In addition to the classical motor symptoms of Parkinson's disease (PD), autonomic symptoms are pervasive in PD and significantly impact quality of life. These autonomic symptoms include, but are not limited to, gastrointestinal, cardiovascular, respiratory, thermoregulatory, and urinary dysregulation. Deep brain stimulation (DBS) is a well-established procedure for reducing motor symptoms of PD, but its effects on autonomic symptoms remain poorly characterized.

This scoping review aims to systematically map existing evidence on the impact of DBS on autonomic symptoms and identify key knowledge gaps.

An electronic search for studies on this topic was conducted in accordance with the Joanna Briggs Institute methodological framework for scoping reviews.

Of 825 unique studies, 57 met inclusion criteria. These studies reported outcomes across five autonomic domains: gastrointestinal (n = 37), cardiovascular (n = 40), respiratory (n = 4), thermoregulatory (n = 13), and urinary (n = 25). Findings across these domains were heterogeneous and limited by inconsistent use of validated outcome measures, varied follow-up intervals, and limited target-specific reporting.

While DBS shows potential benefit in select domains, particularly gastrointestinal and cardiovascular symptoms, its overall efficacy remains unclear. The effects on urinary, thermoregulatory, and respiratory symptoms are especially uncertain. Standardized, prospective studies using validated autonomic assessment tools and detailed reporting of stimulation parameters are needed to clarify the role of DBS in managing autonomic dysfunction in PD.