Brief Answer:
Higher risk of some complications.

Detailed Answer:
I read your question carefully and I understand your concern.

Most patients with Lewy body dementia tolerate surgery well, in particular when in the early stages of the disease, in an active patient.

However there are some risks involved. One such risk is that of confusion and delirium after the surgery. There is such a risk in most elderly patients undergoing anesthesia. In Lewy body patients the risk is higher since the condition itself is associated with confusion and hallucinations.
Another issue is a higher risk of infectious complications such as aspiration pneumonia. This is more present in advanced stages with marked rigidity and limitation of movement, if patient is still XXXXXXX and active the risk is low.
Another possible complication is abnormal movements after exposure to some anesthetic agents such as propofol.

I remain at your disposal for other questions.

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