Double or hybrid diabetes: A systematic review on disease prevalence, characteristics and risk factors

Diabetes mellitus is a worldwide epidemic affecting the health of millions of people. While type 1 diabetes (T1D) is caused by autoimmune destruction of the insulin-producing beta cells of the pancreas, type 2 diabetes (T2D) results from a combination of insulin resistance and beta cell insulin secretory defect. Clear definition and diagnosis of these two types of diabetes has been increasing more and more difficult, leading to the inclusion of a new category, namely double or hybrid diabetes (DD) that demonstrates symptoms of both T1D and T2D via the accelerator hypothesis. In this review, we discuss the worldwide prevalence of DD, its main physiological characteristics, including beta-cell autoimmunity, insulin resistance, and cardiovascular disease, the main risk factors of developing DD, mainly genetics, obesity and lifestyle choices, as well as potential treatments, such as insulin titration, metformin and behavioural modifications. Increasing awareness of DD among the general population and primary care practitioners is necessary for successfully treating this complex, hybrid disease in the future.

Brakes on the accelerator: the journey of accelerator hypothesis from “the missing link” to “an evolving concept”

<p>The incidence of Type 1 diabetes (T1D) has increased significantly over the past few decades but the causes for this increase are poorly understood and hence the strategies for preventing T1D are difficult to design. T1D is characterised by autoimmune destruction of pancreatic β-cells resulting in insulin deficiency as opposed to Type 2 diabetes (T2D) characterised by weight driven insulin resistance (IR). The accelerator hypothesis (AH), proposed by the late Prof Terence Wilkin in 2001 offers an alternative mechanism for T1D and a different approach to prevention of T1D. This hypothesis considers both T1D and T2D as one and proposes that obesity driven IR is the key factor that may lead to either type of diabetes. It thus offers an easy explanation for the increasing worldwide incidence of childhood diabetes which is paralleled by the increase in childhood obesity rates. However, one of the key predictions of AH that the obesity related IR accelerates the onset of diabetes and hence heavier children should develop diabetes at a younger age, has remained a matter of debate since the hypothesis was first proposed. Since the inception of AH, the results of a number of studies which aimed at testing the hypothesis in diverse patient populations have shown support or opposed this key prediction. This article discusses the relevance of AH in the context of data from these studies.</p>