There's all kinds of nonsense talked about window and door security, Gness. No one is ever sure exactly what is needed.
For patio doors... they should be treated much the same as any other external door. With double doors, the problem is that they can be barged inwards from outside. So, "espagnolette" type are usually fitted. They have "shoots" that locate top & bottom into the frame.
So... barging-proof.
The next issue is thus... Insurance companies know that people do break in, or maybe enter through an open window. In that event, their concern is that once inside..... your patio doors can be undone (because there is no deadlock) ... then all kinds of large items can be carried out easily through the patio doors.
The usual answer is to have a lockable espagnolette, or fit "Chubb" mortice key-operated deadlocks into the edges of the 2 doors. These shoot into the frame. So they can't be opened without the key.
These are "Yale"...... same thing...... (ignore the brass - they can be other finishes).
http://www.screwfix.com/p/yale-door-security-bolts-polished-brass-76mm-2-pack/74618?kpid=74618&gclid=CIOesdLZ7dQCFcyRGwodxIYCcA&gclsrc=aw.ds&dclid=CITWxtLZ7dQCFUSmUQod8fMMvw