behaviural change

hi
Am writing this for my dad. he is 74 yrs of age.
he has severe behavioral problems ,like shouting to family members in public, not eating timely food mostly skipping the meals, sleep disorders, urinary incontinence and mood shifts. often he leave the home for no reason and keep himself missing for a day or two.his activity is normal as he manages to do all his daily routine very well. he is not willing to take any responsibility and has issues in making decisions .he had undergone prostrate surgery 2 years back. he is hypo thyroidic.but never takes medicine how so ever we insist.

[Londres70]

Sounds like some type of Dementia.  

He needs a MRI of the brain for starts and a referral to a Neurologist who specializes in Dementia.