The purpose of this study is to investigate whether personalized strategies that target anxiety and stress surrounding freezing of gait can alleviate freezing of gait in people with Parkinson's Disease.

Rationale:

Freezing of Gait (FOG) is a common and disabling symptom in people with Parkinson's Disease (PD), characterized by paroxysmal episodes where there is an inability to step effectively, despite attempting to do so. Treatment consists of complementary pharmacological and non-pharmacological treatment options which unfortunately only partially alleviate FOG. Anxiety has been found to contribute to the occurrence and exacerbation of FOG, which often manifests itself in situations where people with FOG anticipate not being in control of their movements. People with FOG are often aware of the feelings and situations that elicit FOG episodes, but they rarely actively employ strategies targeting their mental state to improve FOG. With the exception of general interventions including mindfulness, yoga and meditation, tailored strategies to ameliorate anxiety-related FOG have never been evaluated in a systematic manner.

Objective:

In this project we aim to evaluate whether a non-pharmacological and tailored intervention targeting anxiety- and stress-related FOG in people with PD is effective to reduce the impact of anxiety and stress on FOG. Specifically, we aim to study: (1) the effect of four sessions of a 'managing the mental state' intervention in people with disabling and anxiety-related FOG; and (2) the key determinants of the effectiveness of the intervention to reduce the impact of anxiety and stress on FOG.

Study design:

This study is a randomized controlled trial (RCT). The intervention group will receive the intervention immediately after randomization while a (waitlist) control group receives the same intervention thereafter.

Study population:

Forty people with PD that experience daily FOG (as objectified with the new-freezing of gait questionnaire) will be included, that is related to anxiety (positive answer to the question: Does FOG occur or get worse when you are anxious or stressed?).

Intervention:

The intervention consists of four sessions of a 'managing the mental state' intervention, of which the first and second session will take place in the home-setting of the patient; the two remaining sessions will take place remotely. The sessions include psychoeducation on what anxiety is and how stress and anxiety can influence FOG, identifying how people are allocating attention and engage in specific thought-processes (e.g. worrisome thoughts) during walking, and educating patients about 'managing the mental state' compensation strategies that involve ways to reduce anxiety or stress and will be specifically tailored to the individual patient.

Main study parameters/endpoints:

The primary outcome involves the percentage of time frozen during a home-based gait trajectory with self-selected FOG 'hotspots'. Secondary outcomes involve the subjective impact of anxiety and stress on FOG, as measured with a Visual Analogue Scale and the perceived levels of anxiety.

Inclusion Criteria:

Men/women of age > 18 years with idiopathic Parkinson's disease, as diagnosed by the UK Brain Bank Criteria;

• Presence of daily FOG (as objectified with the new-freezing of gait questionnaire), that is related to anxiety (positive answer to the question: Does FOG occur -or get worse when you are anxious or stressed?);
• Using a stable dose of PD medication and stability of DBS settings (if applicable) during the trial. Adjustments of PD medication and DBS settings during the trial are allowed if deemed clinically necessary.
• Written informed consent.

Exclusion Criteria:

• Any comorbidity (i.e. neurological, orthopedic) that significantly impacts gait.

  • Severe cognitive impairment hampering the ability to comply to the study protocol.

Randomization will be performed in CastorEDC, a web-based data management system for academic studies (www.castoredc.com). Breaking of the randomization code is not applicable, since researchers and trainers cannot be blinded.