Short-term quality of life after subthalamic stimulation depends on non-motor symptoms in Parkinson's disease

Brain Stimul. 2018 Jul-Aug;11(4):867-874. doi: 10.1016/j.brs.2018.02.015. Epub 2018 Feb 24.

Abstract

Background: Subthalamic nucleus (STN) deep brain stimulation (DBS) improves quality of life (QoL), motor, and non-motor symptoms (NMS) in advanced Parkinson's disease (PD). However, considerable inter-individual variability has been observed for QoL outcome.

Hypothesis: We hypothesized that demographic and preoperative NMS characteristics can predict postoperative QoL outcome.

Methods: In this ongoing, prospective, multicenter study (Cologne, Manchester, London) including 88 patients, we collected the following scales preoperatively and on follow-up 6 months postoperatively: PDQuestionnaire-8 (PDQ-8), NMSScale (NMSS), NMSQuestionnaire (NMSQ), Scales for Outcomes in PD (SCOPA)-motor examination, -complications, and -activities of daily living, levodopa equivalent daily dose. We dichotomized patients into "QoL responders"/"non-responders" and screened for factors associated with QoL improvement with (1) Spearman-correlations between baseline test scores and QoL improvement, (2) step-wise linear regressions with baseline test scores as independent and QoL improvement as dependent variables, (3) logistic regressions using aforementioned "responders/non-responders" as dependent variable.

Results: All outcomes improved significantly on follow-up. However, approximately 44% of patients were categorized as "QoL non-responders". Spearman-correlations, linear and logistic regression analyses were significant for NMSS and NMSQ but not for SCOPA-motor examination. Post-hoc, we identified specific NMS (flat moods, difficulties experiencing pleasure, pain, bladder voiding) as significant contributors to QoL outcome.

Conclusions: Our results provide evidence that QoL improvement after STN-DBS depends on preoperative NMS characteristics. These findings are important in the advising and selection of individuals for DBS therapy. Future studies investigating motor and non-motor PD clusters may enable stratifying QoL outcomes and help predict patients' individual prospects of benefiting from DBS.

Keywords: Deep brain stimulation; Non motor symptoms; Parkinson's Disease Questionnaire; Subthalamic nucleus.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Activities of Daily Living / psychology
  • Aged
  • Deep Brain Stimulation / methods*
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Middle Aged
  • Parkinson Disease / diagnosis*
  • Parkinson Disease / psychology
  • Parkinson Disease / therapy*
  • Prospective Studies
  • Quality of Life* / psychology
  • Registries
  • Subthalamic Nucleus / physiology*
  • Time Factors