Which objective finding is MOST likely to be present in a patient who has Parkinson disease at Hoehn and Yahr Stage 4?

• A. atrial fibrillation
• B. erratic respiration
• C. increased chest excursion
• D. paroxysmal atrial tachycardia

Answer: (B)

In advanced Parkinson disease, autonomic dysfunction and severe motor impairment can disturb automatic control of breathing, leading to an irregular or erratic respiratory pattern. At Hoehn and Yahr Stage 4, the person is severely disabled with marked rigidity and postural instability, and trunk and respiratory muscles may not coordinate effectively. This combination makes erratic respiration a likely objective finding.

Atrial fibrillation and paroxysmal atrial tachycardia are cardiac rhythm issues that aren’t specifically tied to this stage of Parkinson disease. Increased chest excursion would be unlikely because PD rigidity and limited movement tend to reduce, not increase, chest expansion.