Doctors are starting people with Type 2 diabetes on insulin sooner, sometimes at diagnosis. But two recent studies give reason to question this treatment. If you have Type 2, is insulin right for you?
The reason for starting insulin early is simple: Insulin is the quickest way to lower blood glucose levels, and high blood glucose does most of the damage in diabetes. The American Diabetes Association 2014 guidelines say, “In newly diagnosed Type 2 diabetic patients with…elevated blood glucose levels or A1C, consider insulin therapy, with or without additional agents, from the outset.”
Although people with Type 2 make their own insulin, they either do not have enough or are not sensitive enough to it to keep glucose levels down. So the reasoning is, why not help out by injecting more?
But it turns out that in some cases injected insulin may do as much harm as good. Whether it is right for a particular person is an individual decision. A recent study in The Journal of the American Medical Association finds that the negatives may outweigh the positives in many people with Type 2 over the age of 50.
Study coauthor John S. Yudkin said blood sugar levels aren’t everything. Quoted on Diabetes in Control, he said,
The aim of a treatment is not to lower blood sugar for its own sake but to prevent debilitating or deadly complications. If the risk of these complications is suitably correspondingly low and the burden of treatment high, treatment will do more harm than good.
The study followed roughly 5,000 people with Type 2 in the United Kingdom for about 20 years, assessing their quality of life and their rate of complications. They compared the relative risk of complications with the burden and side effects of the treatment.
They found that age makes a big difference. If you begin insulin therapy at age 45 and can lower your A1C by 1%, you may gain 10 months of healthy living. But if you start insulin at age 75, a 1% reduction in A1C could be expected to gain you three weeks of healthy life. In that case you might want to ask if 10–15 years of injections, with their hassles and side effects, would be worth the expected benefit.
“Ultimately,” said Yudkin, “the balance between the two can never be defined by a simple figure like blood sugar level.” It depends on a person’s preferences and abilities. For example, if a person can’t afford glucose monitoring supplies or doesn’t want to monitor, insulin would be a mistake for him.
The researchers caution that their results do not apply to people with an A1C at or over 8.5%. Those with high numbers are at more risk and more likely to benefit from insulin.
Another large review, conducted at Vanderbilt University and published in The Journal of the American Medical Association, also takes a dim view of insulin in Type 2. In this study, it was found that lifespan may be reduced when insulin is added to the treatment of people already receiving metformin.
Researchers evaluated the records of more than 178,000 people who were taking metformin. When metformin fails to lower A1C to the target range (usually 7%), a second drug is often added. In this study, 2,948 added insulin and 39,990 added a sulfonylurea drug. Sulfonylureas tell the pancreas to produce more insulin on its own.
Patients’ records were followed for approximately 14 months after they started their second drug. Although the rates of heart attack and stroke were similar, there was a higher death rate among the people receiving insulin.
Why would insulin lead to higher death rates? The authors wrote that weight gain and hypoglycemic episodes (lows) caused by insulin might explain the poorer outcomes.
Hypoglycemia puts tremendous strain on the heart, causing it to pump harder while its own blood supply is reduced. It’s a huge stressor. The strain of hypoglycemic episodes on the heart may cancel out the cardiac benefits of tighter glucose control.
But please note that sulfonylureas can cause lows too. The risks of “tight control” only apply to tight control achieved through certain drugs, not to control achieved by healthier living.
So if you are considering insulin, or if you are on it and have experienced lows, you might ask your doctor if the risk is worth it for you. You might be better off with one of the incretin drugs (Byetta, Bydureon, Victoza, Januvia, Janumet, Janumet XR, Juvisync, Onglyza, Kombiglyze XR, Nesina, Kazano, Oseni, Tradjenta, Jentadueto) or with natural remedies such as a low-carb diet, exercise, vinegar, or bitter melon.
Of course, if insulin is working for you, you should probably keep taking it. As all studies conclude, the right decision is different for each person. Choose what’s right for you.