Mysteries of type 2 diabetes: the Indian Elephant meets the Chinese Dragon

Risk prediction models for type 2 diabetes using either fasting plasma glucose or HbA1c in Chinese, Malay, and Indians: Results from three multi-ethnic Singapore cohorts

AIMS

To assess three well-established type 2 diabetes (T2D) risk prediction models based on fasting plasma glucose (FPG) in Chinese, Malays, and Indians, and to develop simplified risk models based on either FPG or HbA1c.

METHODS

We used a prospective multiethnic Singapore cohort to evaluate the established models and develop simplified models. 6,217 participants without T2D at baseline were included, with an average follow-up duration of 8.3 years. The simplified risk models were validated in two independent multiethnic Singapore cohorts (N = 12,720).

RESULTS

The established risk models had moderate-to-good discrimination (area under the receiver operating characteristic curves, AUCs 0.762 - 0.828) but a lack of fit (P-values < 0.05). Simplified risk models that included fewer predictors (age, BMI, systolic blood pressure, triglycerides, and HbA1c or FPG) showed good discrimination in all cohorts (AUCs ≥ 0.810), and sufficiently captured differences between the ethnic groups. While recalibration improved fit the simplified models in validation cohorts, there remained evidence of miscalibration in Chinese (p ≤ 0.012).

CONCLUSIONS

Simplified risk models including HbA1c or FPG had good discrimination in predicting incidence of T2D in three major Asian ethnic groups. Risk functions with HbA1c performed as well as those with FPG.

Pathophysiology, phenotypes and management of type 2 diabetes mellitus in Indian and Chinese populations

Nearly half of all adults with type 2 diabetes mellitus (T2DM) live in India and China. These populations have an underlying predisposition to deficient insulin secretion, which has a key role in the pathogenesis of T2DM. Indian and Chinese people might be more susceptible to hepatic or skeletal muscle insulin resistance, respectively, than other populations, resulting in specific forms of insulin deficiency. Cluster-based phenotypic analyses demonstrate a higher frequency of severe insulin-deficient diabetes mellitus and younger ages at diagnosis, lower β-cell function, lower insulin resistance and lower BMI among Indian and Chinese people compared with European people. Individuals diagnosed earliest in life have the most aggressive course of disease and the highest risk of complications. These characteristics might contribute to distinctive responses to glucose-lowering medications. Incretin-based agents are particularly effective for lowering glucose levels in these populations; they enhance incretin-augmented insulin secretion and suppress glucagon secretion. Sodium-glucose cotransporter 2 inhibitors might also lower blood levels of glucose especially effectively among Asian people, while α-glucosidase inhibitors are better tolerated in east Asian populations versus other populations. Further research is needed to better characterize and address the pathophysiology and phenotypes of T2DM in Indian and Chinese populations, and to further develop individualized treatment strategies.

Basal insulin therapy: Unmet medical needs in Asia and the new insulin glargine in diabetes treatment

Diabetes remains a global epidemic and a tremendous health challenge, especially in the Asian population. Dramatic increases in the prevalence of diabetes across different countries or areas in Asia have been reported in recent epidemiological studies. Although clinical guidelines have strengthened appropriate antihyperglycemic medications and lifestyle modifications for optimal diabetes management, inadequate glycemic control still occurs in many patients with an increased risk of developing microvascular and macrovascular complications. Insulin administration is the main therapy for diabetes in response to the inability to secrete insulin, and is recommended in current guidelines to treat patients with type 2 diabetes after failure of oral antidiabetic drugs. Clinical studies have shown that long-acting insulin analogs improve basal glycemic control with reduced risk of hypoglycemia. In the present review, we discuss previous challenges with basal insulin therapy in Asia, the pharmacological development of insulin analogs to overcome the unmet medical needs and recent clinical studies of the new ultra-long-acting insulin analog, insulin glargine U300. Furthermore, relevant findings of current real-world evidence are also included for the comparison of the efficacy and safety of different insulin formulations. Based on the accumulating evidence showing a low incidence of hypoglycemia and technical benefits of dose titration, treatment with glargine U300 can be a promising strategy for Asian diabetes patients to achieve glycemic targets with favorable safety.

Public health and health systems: implications for the prevention and management of type 2 diabetes in south Asia

Many non-communicable chronic diseases, including type 2 diabetes, are highly prevalent, costly, and largely preventable. The prevention and management of type 2 diabetes in south Asia requires a combination of lifestyle changes and long-term health-care management. However, public health and health-care systems in south Asian countries face serious challenges, including the need to provide services to many people with inadequate resources, and substantial between-population and within-population inequalities. In this Series paper, we explore the importance and particular challenges of public health and health systems in south Asian countries (Bangladesh, Bhutan, India, Nepal, Pakistan, and Sri Lanka) with respect to the provision of culturally appropriate lifestyle modification to prevent and manage diabetes, especially in resource-poor settings. Effective primary prevention strategies are urgently needed to counter risk factors and behaviours preconception, in utero, in infancy, and during childhood and adolescence. A concerted focus on education, training, and capacity building at the community level would ensure the more widespread use of non-physician care, including community health workers. Major investment from governments and other sources will be essential to achieve substantial improvements in the prevention and management of type 2 diabetes in the region.