Canine diabetes mellitus is one of the most common and serious endocrine disorders diagnosed in pet dogs. It’s often debilitating, sometimes deadly, and almost always expensive to treat. Studies suggest that it’s getting more common too.
In lay terms, the disease is characterized by having too much sugar (glucose) in the bloodstream and not enough in the other tissues that need it. But, in a way, the disease is less about glucose and more about the body’s production and use of the hormone insulin.
Insulin’s primary function is to drive circulating glucose into tissues like fat and muscle. In diabetic animals that process becomes dysfunctional, so more and more glucose stays in the blood instead. If left untreated, the resulting condition (hyperglycemia) can cause debilitating damage to the eyes, kidneys, and cardiovascular system.
There are a few different ways that glycemic control can become disrupted. In what’s typically called insulin-deficiency diabetes (IDD), the pancreas simply stop producing enough insulin. In insulin-resistant diabetes (IRD), insulin production remains normal (or is elevated), but peripheral tissues become desensitized to the hormone, so they no longer suck up glucose effectively. In IDD, there’s not enough insulin being produced; in IRD, the insulin no longer does its job effectively. In both cases, persistent hyperglycemia is likely to result without treatment.