THURSDAY, Oct. 16, 2025 (HealthDay News) -- Subthalamic deep brain stimulation (DBS) is an effective long-term therapy for Parkinson disease (PD), according to a study published online Sept. 15 in JAMA Neurology.Philip A. Starr, M.D., Ph.D., from the University of California, San Francisco, and colleagues assessed the long-term outcomes of subthalamic stimulation for the treatment of PD. The analysis included 137 of 191 participants who received the Vercise DBS system and completed five-year follow-up.The researchers found that motor function without medication (measured by the Unified Parkinson’s Disease Rating Scale [UPDRS-III]) improved from a mean of 42.8 to 21.1 at year 1 (51 percent) and 27.6 at year 5 (36 percent). Similarly, activities of daily living without medication, also measured by the UPDRS-III, improved from a mean of 20.6 to 12.4 at year 1 (41 percent) and 16.4 at year 5 (22 percent). There was a decrease in dyskinesia scores from 4.0 to 1.0 at year 1 (75 percent) and to 1.2 at year 5 (70 percent). At year 1, the levodopa equivalent dose was reduced by 28 percent, which remained stable at year 5 (28 percent). Infection was the most common serious adverse event, seen in nine participants."DBS used to be seen as a last resort, but we now know it provides the most sustained benefit when offered in the moderate stages of PD, when motor complications are the main source of disability," coauthor Adolfo Ramirez-Zamora, M.D., from University of Florida Health in Gainesville, said in a statement.Several authors disclosed financial ties to the pharmaceutical and medical device industries, including Boston Scientific, which funded the study.Abstract/Full Text.Sign up for our weekly HealthDay newsletter