Type 1 diabetes is often diagnosed in childhood or early adulthood. It develops when the pancreas doesn’t make enough of the hormone insulin to help sugar in the blood enter cells where it can be used for energy, according to the Centers for Disease Control and Prevention (CDC). Results from the study suggest that the pancreas may malfunction in different ways depending on how old children are when they’re diagnosed with type 1 diabetes, potentially impacting how well they respond to treatments designed to lower blood sugar levels. “Children develop type 1 diabetes because their own bodies turn against themselves and mount an attack by the immune system, targeted to destroy their insulin-producing cells very selectively,” says senior study author Noel Morgan, PhD, a professor of endocrine pharmacology at the University of Exeter Medical School in England. “We have found that the nature of this attack differs in very young children compared to those who are older such that it is much more aggressive at early ages,” Dr. Morgan says. RELATED: How Is Type 1 Diabetes Treated?
Pancreas Tissue Appears to Differ by Age of Type 1 Diabetes Diagnosis
To investigate differences in type 1 diabetes based on age at diagnosis, researchers examined clusters of pancreas tissue known as islet cells, which are responsible for making insulin. Islets include two types of cells: alpha cells, which make the hormone glucagon that is responsible for increasing levels of glucose, or sugar, in the blood; and beta cells, which make insulin to lower glucose levels. In healthy people, alpha and beta cells work in tandem to maintain healthy levels of blood sugar and help fuel cells throughout the body with the energy they need to function properly. Kids in the study who were diagnosed before age 7 had a greater loss of beta cells and released higher levels of proinsulin (the precursor of insulin) into the body, the analysis found. Proinsulin doesn’t work as well as insulin at helping cells convert blood sugar into energy, potentially leading to higher blood sugar levels in young kids with type 1 diabetes than with older people who have this disease, Morgan says. By contrast, children diagnosed with type 1 diabetes at age 13 or older appeared to have a less intense immune attack on islet cells in the pancreas and more beta cells capable of producing insulin. In these patients, the pancreas released less proinsulin and more insulin, the analysis found. “Because we have found that older children (older than 13 at diagnosis) retain more beta cells than expected at diagnosis (and beyond), this raises the possibility that these cells might be reinvigorated to increase their release of natural insulin,” Morgan said in an email. “This would then lead to better blood glucose control.” Among kids diagnosed between 7 and 12 years old, some had tissue samples similar to younger children and some had samples that looked more like patients diagnosed during their teen years. RELATED: Your Top Type 1 Diabetes Questions, Answered
A Small Sample Size and Limited Age Group Are 2 Limitations of the Study
For the study, researchers examined 32 pancreas tissue samples from organ donors. They had samples from 19 participants, including five people diagnosed before age 7, seven diagnosed from ages 7 to 12, and seven diagnosed from ages 13 to 19. Beyond the small size, a drawback of the study is that many of the tissue samples came from people who had what’s known as diabetic ketoacidosis (DKA) when they died. The Mayo Clinic notes that DKA happens when the body doesn’t produce enough insulin and generates high levels of a blood acids called ketones. This leads to dangerously high blood sugar. It’s possible that the islet cell observations from participants who experienced DKA wouldn’t represent the islet cells in people with type 1 diabetes who have well-controlled blood sugar, the study team notes. Another limitation is that researchers only looked at people who developed type 1 diabetes in childhood or adolescence, and it’s possible that results wouldn’t reflect what would happen with individuals diagnosed as adults, researchers point out. RELATED: Study Ties Inflammation, Gut Bacteria to Type 1 Diabetes
The Study Results Echo Some Scientists’ Hypothesis About Type 1 Diabetes
While more research is needed, the new findings support a hunch long held by clinicians and researchers that there may be more than one form of type 1 diabetes, says Bart Roep, PhD, chair of diabetes immunology at City of Hope in Los Angeles. “The diabetes field already had a gut feeling that patients and their type 1 diabetes differs,” says Dr. Roep, who wasn’t involved in the study. “When patients read about their disease, it rarely feels like their own, and they were right: The diversity is much greater than we thought or predicted.” This may help explain why some trials of immune therapies for type 1 diabetes haven’t shown a clear benefit for patients, and why some kids don’t respond as well to treatment as others, Roep says. “If the disease differs between patients, there cannot be a ‘magic bullet’ therapy fit for all,” Roep adds.
