Effect of Trunk Flexion on Airway Defense in Parkinson's Disease

Effect of Forward Trunk Flexion in Patients With Parkinson's Disease on the Airway Defense System

The main mechanisms of airway protection include a properly functioning swallowing process and a cough. Studies focusing on patients with Parkinson's disease (PD) have previously demonstrated impairments in both swallowing (dysphagia) and coughing (dystussia). Aspiration pneumonia is the leading cause of death in individuals with PD.

Swallowing function is directly related to body posture. Postural abnormalities (PA) are a common symptom of PD and significantly contribute to patient disability, affect respiratory function, and reduce quality of life. Previous research has shown that more than 20% of PD patients suffer from some form of PA.

Most PD patients with a forward trunk flexion angle greater than 30 degrees report specific difficulties, such as dysphagia. A link has previously been demonstrated between postural abnormalities associated with flexed posture and restrictive ventilatory impairment. It can be assumed that this restrictive ventilatory impairment, which reduces the amount of air the patient can inhale into the lungs and subsequently exhale, negatively affects the strength of voluntary cough. However, this hypothesis has not yet been verified in the mentioned patient group.

The primary aim of the study will be to examine the effect of forward trunk flexion (FTF) in Parkinson's disease on the airway defense system.

The primary aim of the study will be to verify the potential relationship between forward trunk flexion, respiratory muscle strength, and the strength of voluntary cough.

Hypotheses:

1. Forward trunk flexion in patients with Parkinson's disease (PD) will negatively affect respiratory muscle strength and the strength of voluntary cough.
2. Respiratory muscle strength and the strength of voluntary cough will deteriorate more rapidly over a three-year period in patients with PD and forward trunk flexion than in patients with PD without forward trunk flexion.

The secondary aim will be to correlate respiratory muscle strength and the strength of voluntary cough with handgrip strength and the pulmonary dysfunction index as potential screening methods.

Hypothesis:

1. Handgrip strength and the pulmonary dysfunction index will correlate with respiratory muscle strength and the strength of voluntary cough.

Inclusion Criteria:

• Diagnosis of Parkinson' s disease
• Age ≥ 18 years

Exclusion Criteria:

• Unreliable performance of MIP, MEP, or grip strength measurements, for example, due to cognitive deficits (assessed by the researcher)
• Inadequate lip seal
• Significant deformities of the dominant hand that could affect the accuracy of grip strength measurements
• Other severe neurological diseases apart from PD
• History of unstable cardiovascular disease
• Severe pulmonary disease