Have You Met Diabetes Type 1.5?
Updated: Oct 7
Type 1.5 diabetes, or Latent Autoimmune Diabetes in Adults (LADA), is an adult-onset, slow-progressing version of type 1 diabetes. How does it compare with other forms of diabetes including types 1 and 2 or even pre-diabetes? And how does it provide a window into potentially reversing some of these conditions?
Type 1.5 diabetes, or Latent Autoimmune Diabetes in Adults (LADA), is an adult-onset, slow-progressing version of type 1 diabetes. In this condition the pancreas is still capable of producing insulin, but the presence of one or more autoantibodies against insulin-producing pancreatic beta cells leads to the slow destruction of beta cells over time. LADA has characteristics of both type 1 diabetes and type 2 diabetes and is often misdiagnosed as other forms of diabetes, resulting in the wrong treatment.
But before we expand further on LADA, let's review the other forms of blood sugar/glycemic dysregulation:
Type 1 diabetes, or Insulin-Dependent Diabetes Mellitus (IDDM), describes the complete destruction of the pancreatic β-cells (beta cells) which produce insulin. This is classified as an auto-immune disease and most often occurs among children and adolescents, requiring lifelong use of insulin.
Type 2 diabetes, or Non-Insulin-Dependent Diabetes Mellitus (NIDDM), usually occurs after the person is 40 years of age. It is marked by an ever-increasing cellular insensitivity to insulin and has a strong correlation with diet.
Gestational diabetes is unique to pregnant women and often goes away after the baby is born. However, gestational diabetes does increase the chance of developing type 2 diabetes later in life. Also, sometimes the diabetes diagnosed during pregnancy is actually type 2 diabetes.
Pre-diabetes describes the state of an adult whose elevated blood sugar and insulin levels continually slide into abnormally high ranges yet remain below the diagnostic range used to identify diabetes.
Metabolic syndrome is a set of risk factors found to increase a person's likelihood of acquiring NIDDM, heart disease or stroke. These risk factors include increased waist circumference, blood pressure, blood glucose and/or insulin resistance, triglycerides, or decreased HDL cholesterol. People with metabolic syndrome are usually pre-diabetic.
The American Diabetes Association (ADA) considers LADA as T1DM that evolves more slowly than the classic disease and does not recognize it as a specific type of DM, but not all professional organizations share this stance. The Immunology for Diabetes Society (IDS) has identified 3 main criteria for establishing a diagnosis of LADA. These three factors must be present in order for a patient to be diagnosed with LADA:
---- Adult age of onset (greater than 30 years)
---- The presence of at least 1 islet cell autoantibody
---- The absence of insulin requirement for at least 6 months after diagnosis; those living with type 1 diabetes often require exogenous insulin almost immediately after diagnosis, whereas those with type 1.5 diabetes may not require insulin therapy for between 6 months and 5 years after diagnosis.
The Misdiagnosis of LADA for type 2 NIDDM
It turns out that people with LADA are often misdiagnosed with type 2 diabetes for three main reasons:
---- Diabetes onset occurs after the age of 30
---- β-cell destruction occurs over the course of time (as opposed to sudden-onset type 1 diabetes)
---- They are unaware of their autoimmune status and are lacking a diabetes antibody panel to test for the autoantibodies GADA, IAA, IA-2A, ICA, and/or ZnT8
Why does the misdiagnosis matter? The misdiagnosis is important because treatment emphasis can change with different conditions. In type 2 NIDDM, the emphasis is on keeping the blood sugar levels within a goal range and treating other medical conditions that go along with diabetes. However, in LADA, the goal is preservation of pancreatic β-cell function and attempting to keep auto-immunity from advancing, while also maintaining glycemic levels. With the goals of LADA treatment in mind, then some of the classic type 2 NIDDM prescription treatments like "[s]ulfonyl-ureas are a poor choice for LADA. They deplete β-cells of insulin as depicted by falling C-peptide levels, the persistence of antibodies, and the earlier progression to insulin". (1) Yet different prescriptions and various herbal medicines have been shown to be protective or even restorative to pancreatic β-cell function! (2)
Furthermore, naturopathic physicians often make comprehensive assessments to identify things known to provoke auto-immune responses. These can include more than just a person's genetic predisposition but undiagnosed infections, food allergies or sensitivities, and environmental contaminants like heavy metals, bisphenol A (BpA) and phthalates.(3,4) Most conventional doctors treating for type 2 NIDDM would never even consider glancing in such directions for case management.
On the High Seas: C-Peptide
C-peptide is produced in equal amounts to insulin and remains "... the best measure of endogenous insulin secretion in patients with diabetes". (5) Measurement of insulin secretion using C-peptide can be helpful in clinical practice because differences in insulin secretion are fundamental to the different treatment requirements of types 1 and 2 diabetes. It has been known for decades that some C-peptide is associated with less complications in type 1 diabetes and it has become accepted as a relevant outcome in attempts to preserve of β-cell function. Preservation of β-cell function is important to make diabetes milder, and if β-cell function could be preserved before clinical manifestation of type 1 diabetes, then that may unlock the actual prevention of that disease. "Residual C-peptide/insulin secretion can be of value in classification of diabetes in different types. C-peptide may give valuable clinical information on why patients are more or less stable/labile in their blood glucose and more or less easy to treat". (6)
When managing LADA or other types of glycemic discord, C-peptide levels should be monitored routinely in addition to other important diabetes biomarkers. A medium C-peptide value indicates that a person may have adequate insulin production to fully reverse prediabetes or type 2 diabetes; however, it’s imperative to maximize insulin sensitivity in order to prevent β-cells from becoming exhausted over time and this may require some extensive dietary efforts. (7,8)
By contrast, a low C-peptide measurement means that the β-cells have been potentially permanently impaired and that individual may require exogenous insulin to control blood glucose longterm, unless tactics to address the autoimmunity prove fruitful and facilitate some margin of pancreatic recovery.
In conclusion, the largely unrecognized status of LADA and untested values for C-peptide have resulted in a significant number of people with type 2 diabetes being told to inject insulin when perhaps, if have a medium or high C-peptide value, they can fully reverse the insulin resistance using lifestyle modification and other techniques to address autoimmunity.
If you or someone you love is faced with these concerns, consider contacting our clinic and finding out how we could be of service.
Rajkumar V, Levine SN. Latent Autoimmune Diabetes. [Updated 2022 Jun 21]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK557897/
Jones, A G, and A T Hattersley. “The clinical utility of C-peptide measurement in the care of patients with diabetes.” Diabetic medicine : a journal of the British Diabetic Association vol. 30,7 (2013): 803-17. doi:10.1111/dme.12159.
Lim, E L et al. “Reversal of type 2 diabetes: normalisation of beta cell function in association with decreased pancreas and liver triacylglycerol.” Diabetologia vol. 54,10 (2011): 2506-14. doi:10.1007/s00125-011-2204-7.
Taylor, Roy et al. “Remission of Human Type 2 Diabetes Requires Decrease in Liver and Pancreas Fat Content but Is Dependent upon Capacity for β Cell Recovery.” Cell metabolism vol. 28,4 (2018): 547-556.e3. doi:10.1016/j.cmet.2018.07.003.
The content and any recommendations in this article are for informational purposes only. They are not intended to replace the advice of the reader's own licensed healthcare professional or physician and are not intended to be taken as direct diagnostic or treatment directives. Any treatments described in this article may have known and unknown side effects and/or health hazards. Each reader is solely responsible for his or her own healthcare choices and decisions. The author advises the reader to discuss these ideas with a licensed naturopathic physician.