Is this a problem with the structure?

[dgghr]

I would like to know if there is an issue with the structure above the sliding glass door in my home. Above the door ( between the door and the ceiling on both sides) cracks have appeared in the sheet rock and have continued to get worse and worse. I am not good at repairing these kinds of things so I have let it continue. I am at a point where I am concerned and I need to do something about it. Do I need to have it looked at or can it just be covered over. I have attached a couple of pictures. Thanks

[pushkins]

I'm assuming these two cracks are in very similar places to each other on both sides of the door and most likely both run very closely to be in line with the edge of the physical door ?
I see this many times and usually (baring spongy floors in front of the door) this is caused by the drywall having a joint at this point. Ideally the drywall should be cut so the sheet joints at some point over the door like an inverted "L" shape. Many times at installation they will just line it up with the door edge (or window) on either side and cut a piece to fit between either sheet on either side and over the door, this will almost always lead to cracks like your picture shows.
Typically speaking structural issues appear as a crack that has a larger opening at the top and progressively getting smaller towards the bottom and almost always are accompanied with other cracks (horizontal) like at the junction of the wall and ceiling where the wall is dropping away from the ceiling for example.
The problem here appears to be more cosmetic but is difficult to permanently fix, you can use mesh tape and apply drywall compound, sand and paint, but typically just buys time and at some point the crack will start again, a lot will depend on how well the door is attached to the house and how stiff the framing is around the door, if the door is just a little "loose" it allows a small amount of movement and this is what causes the crack.

[Drywall DIY Guy]

You have what appears to be a stress crack caused by temperature extremes. It is very common and probably not a structure defect, but more an oversight in the drywall installation. One should never ever have a seam above (or below) an exterior door or window corner when one lives in a cold climate, even though it is very convenient to do so. Instead, have the drywall flow over the corner with a seam midway in-between as shown in the pic at http://www.drywallinfo.com/images/window-joints.GIF

You can possibly fix this by retaping with high-strength crack repair tape - I once fixed a small crack this way and the repair lasted for years - I used a Strait flex product. Or for a permanent fix, remove drywall and reconfigure it, as shown at How To Repair Holes in Drywall and Cracks in Walls