Latent Autoimmune Diabetes in Adults
Reviewed by endocrinologist Stanley S. Schwartz, MD, emeritus Associate Professor of Medicine at the University of Pennsylvania and George Grunberger, MD, FACP, FACE, Chairman of the Grunberger Diabetes Institute, Clinical Professor of Internal Medicine and Molecular Medicine & Genetics at Wayne State University School of Medicine and President of the American Association of Clinical Endocrinologists
Call it diabetes type 1.5. Double diabetes. Or “slim type 2.” By any name, LADA—latent autoimmune diabetes in adults—plays by its own rules.
Similar to type 1 diabetes, in LADA the immune system attacks and destroys insulin-making beta cells in the pancreas. But it progresses more slowly than type 1. Like type 2, it tends to happen after age 30. That’s just one reason LADA is usually misdiagnosed as type 2. Like typical type 2s, people with LADA may be insulin resistant; their bodies don’t respond readily to insulin’s signals to absorb blood sugar. And LADA can usually be controlled for months or years with pills and other non-insulin blood-sugar medications used by type 2s. But eventually, people with LADA need daily insulin shots or a pump to control their blood sugar.1
Researchers are still delving into LADA’s true nature. Some experts think it’s simply slow-motion type 1. Others have a hunch LADA’s got its own unique genetic signature.2 Up to 10% of people with type 2 may have LADA. “Knowing you have LADA could help your doctor choose early medications that can preserve beta cells longer. And it could help you and your doctor move you to insulin therapy sooner when blood sugar levels rise,” explains endocrinologist Stanley S. Schwartz, MD, an emeritus Associate Professor of Medicine at the University of Pennsylvania.
Is it LADA?
Blood glucose tests will tell you and your doctor whether you have diabetes – but not if the type you have is LADA. “The only way to diagnose LADA is with a blood test for islet-cell antibodies,” says George Grunberger, MD, FACP, FACE, Chairman of the Grunberger Diabetes Institute, Clinical Professor of Internal Medicine and Molecular Medicine & Genetics at Wayne State University School of Medicine and President of the American Association of Clinical Endocrinologists.
Islet autoantibodies are chemicals that show up in the bloodstream when beta cells are under attack. An antibody test can measure signs of trouble years before beta cells are totally destroyed , giving you and your doctor the chance to plan a smart strategy for taking care of LADA. 3
Common antibody blood tests look for glutamic acid decarboxylase antibodies (GADA) – an antibody to an enzyme in beta cells; insulin autoantibodies (IAA) – antibodies that target insulin; and insulinoma-associated-2 autoantibodies (IA-2A) – another antibody to a beta cell enzyme. “If your test is positive for even one antibody, you have autoimmune diabetes,” Dr. Grunberger says. Some doctors also order tests for C-Peptide, a protein associated with insulin levels. While levels are low in type 1s, they will usually be higher with LADA because your body is still producing some insulin.
Signs that you may have LADA, instead of type 2, including being thin, having a personal or family history of autoimmune disease, blood sugar levels that keep rising despite a healthy lifestyle and several diabetes drugs, and having healthy blood pressure and cholesterol levels.
Diabetes Medications and LADA
Most people with LADA will start out with medications for type 2. “The three best classes of medications for people with LADA are thiazolidinediones [rosiglitazone (Avandia) and pioglitazone (Actos)], GLP-1 receptor agonists [such as albiglutide (Tanzeum), dulaglutide (Trulicity), exenatide (Bydureon, Byetta) and liraglutide (Victoza), and metformin,” Dr. Grunberger says. “These can help preserve beta-cell mass, which is especially important when you have LADA.”
Dr. Grunberger and Dr. Schwartz both warn against using sulfonylureas [such as glimepiride (Amaryl), glipizide (Glucotrol ) and glyburide (DiaBeta) and others). “They help blood sugar at first, but slowly poison beta cells,” Dr. Grunberger says. “If you still have working beta cells, sulfonylureas are the worst choice.” A 2011 review of LADA treatments, from the Cochrane Collective, concluded that “the drug sulphonylurea (like glibenclamide or glyburide, gliclazide) could make patients insulin dependent sooner.” 4
A healthy, carbohydrate-controlled eating plan along with exercise and weight loss can also help your beta cells control your blood sugar better, he says. “Improving insulin sensitivity will allow the insulin you do have to work better. Reducing carbohydrates to a level recommended by your doctor will also keep your blood sugar a little lower, so insulin doesn’t have to move as much glucose into your cells,” Dr. Grunberger says. “I work in Detroit. We use car analogies here. If you have a limited supply of gas, driving a compact car will make that gas last longer than driving a Hummer. If you have limited insulin, make the most of it.”
And be prepared for the day when you do need insulin injections or a pump. Most people with LADA need insulin within six years of their diabetes diagnosis. “Needing insulin is not a failure,” he says. “When your body cannot produce it, it’s time to move to insulin. You’ll need it for blood glucose control and to lower your risk for complications.” 5