Excessive thirst is not a sign of diabetic complications, but it usually is a sign of poorly controlled glucose levels -- which greatly increases the risk for complications such as eye, kidney, nerve, heart and blood vessel disease. When glucose levels are above 180 mg/dl (10 mmol/l), some sugar passes through the kidneys into the urine and draws water along with it. This produces excess urination and dehydration which, in turn, produces thirst. Excessive thirst usually means that the glucose levels have been elevated.
Hopefully you are monitoring your glucose levels with fingerstick measurements or a continuous glucose monitoring device. If not, start doing so right away and share the results with your physician so that your diabetes management therapy can be properly adjusted.