Does the diabetic eye disease cause vision loss?

It can. There are many forms of eye disease related to diabetes. Some affect the vision immediately while others do not. However, if left unchecked, all forms of diabetic eye disease are likely to reduce vision. See your eye doctor regularly.
See a retina special. A retina specialist is the correct person to treat the different kinds of diabetic retinopathy. For diabetic macular edema: laser, eye injections of medicine (anti-vegf and steroids). For proliferative diabetic retinopathy: laser, eye injections of medicine. For vitreous hemorrhage: vitrectomy surgery with laser. For tractional retinal detachment: vitrectomy, with laser and membrane peeling.