IMO, this is isn't as innocent a way to proceed as you appear think.
Doc asks if you have guns in your home.
You calmly answer no. Doc checks No on your medical record.
An injury or death occurs that involves one of your guns.
The court subpoena's your dr. and your medical record.
It's determined you owned the gun at the time you lied to the dr.
You've now got additional legal issues to contend with.
"...the court subpoenas your medical and doctor records..."