The medical treatment of patients with Parkinson
Alexoudi A, Shalash A, Knudsen K, Witt K, Mehdorn M, Volkmann J, Deuschl G. The medical treatment of patients with Parkinson , 2015 Jun;21(6):555-60. doi: 10.1016/j.parkreldis.2015.03.003. Epub 2015 Mar 20
Introduction: Pharmacotherapy is the first line treatment for symptoms of Parkinson’s disease (PD). However medications have side effects and lose efficacy as the disease progresses. Surgical intervention, such as deep brain stimulation of the subthalamic nucleus (DBS STN), is an additional treatment approach that has shown successful reduction in motor symptoms as well. Typically after DBS STN the person with PD (PWP) also does not require as much dopaminergic medications and reductions are common. The purpose of this study was to take a closer look at the specifics regarding medication reduction over 3-10 years postsurgery.
Methods: Subjects of this study initially included one hundred PWP that underwent bilateral DBS STN in Germany between 1999 and 2007 (2/3 male, 1/3 female). Multiple age groups and disease duration groups were stratified. The authors looked at retrospective longitudinal data at 6 months, 3 years, 5-6 years (N=58), and 10 years + (N=15) postsurgery.
Results: The dosages for levodopa and dopamine agonists were reduced by half at 6 months and around 45% at three years. Notably 9% of the PWP were medication free at 6 months and 6% at three years. There was also a switch, 6 months postsurgery, to many more patients only having to take one medication versus multiple (27 vs. 56%, pre to post) which continued at the three year mark. The usage of amantadine was also reduced along with the dosage amount of the medication at both the 6 months and 3 year mark. Anticholinergics were almost entirely stopped. The PWP had reduction in their motor symptoms and medication costs declined by 50-60% over time. When looking at the stratified age of onset groups, it was found that the older group (>45 vs.
Continued reduction from baseline levels were found when looking at the 5-6 year and 10 year follow ups. Only one patient at the 5 and 10 year follow ups remained medication free. Other medications were also monitored and there was a reduction in the usage of neuroleptics (refers to antipsychotic medications to treat hallucinations or psychosis) at six months but increases in usage at the 3 year follow up. A similar finding occurred with antidepressants with an increase at 3 and 5-6 years.
Conclusion: This study found significant reductions in levodopa medications and dosages after DBS STN that continued up to 10 years postsurgery. Other adjuvant medications were also reduced or eliminated. It was noted that there was an increase in usage of antidepressants which was thought possibly related to dopaminergic medication withdrawal from reduction of the levodopa. Continued monitoring and treatment of psychiatric symptoms was necessary due to disease progression. Lastly, the reduced cost of medications over the years was highlighted and should be taken into consideration. Although the aforementioned data provides findings from 1999 and 2007, the impact of DBS on symptom improvement and medication utilization continues to be investigated.