Since 1990, rising diabetes rates in lower-income countries have outpaced improvements in care, while wealthier nations have seen the greatest treatment advances, widening the global diabetes gap.

A recent study published in The Lancet examined global trends in diabetes prevalence and treatment coverage between 1990 and 2022 to gain insights into the shifting burden of diabetes and identify treatment gaps and disparities between low-income and high-income regions.

The findings highlighted the stark discrepancy between the rise in diabetes prevalence and improvements in diagnosis and treatment options in middle- and low-income countries.

Background

Diabetes has become a major global health concern and is linked to serious complications such as cardiovascular disease, kidney failure, and vision loss. Managing diabetes requires early detection and effective treatments, such as oral medications and insulin, which can reduce the risk of long-term health issues.

Over the recent few decades, the incidence rates of diabetes have risen in many regions, largely driven by an increase in obesity, especially in low- and middle-income countries. Although affordable, generic medications such as metformin are widely available, access to these diabetes medications is unequal.

High-income nations have generally seen improvements in diabetes care, while many low-resource areas face limited access to treatment options, resulting in a population of untreated and often undiagnosed diabetes patients with substantial risks for complications. Furthermore, despite previous studies on diabetes prevalence and care, the global data on the changes in diabetes prevalence and treatment coverage has thus far been inadequate for understanding trends and disparities in diabetes management worldwide.

About the study

In the present study, the researchers used data from 1108 population-based studies consisting of over 141 million participants above the age of 18 to examine trends in diabetes prevalence and treatment between 1990 and 2022 across 200 countries. They gathered data on fasting glucose and glycated hemoglobin or HbA1c levels, as well as diabetes medication use.

The researchers used the data on fasting plasma glucose (FPG) and HbA1c levels to define diabetes as having an FPG of 7.0 millimoles per liter or higher, an HbA1c equal to or greater than 6.5%, or current use of diabetes medications.

Treatment coverage trends were assessed by analyzing changes over time in both age-standardized prevalence and treatment rates, which provided the researchers with insights into healthcare system responses worldwide. Regional data were grouped into 20 regions and eight super-regions, such as high-income Western countries, South Asia, and sub-Saharan Africa, allowing for more detailed comparisons across economically and geographically diverse regions.

Major findings

The study found that the prevalence of diabetes had increased substantially worldwide between 1990 and 2022, with low- and middle-income countries, with South Asia, the Middle East, and parts of Africa experiencing a marked increase.

In 2022, an estimated 828 million adults worldwide had diabetes, which was a substantial increase from 198 million in 1990. The highest age-standardized prevalence was observed in regions such as Micronesia and Polynesia, parts of the Caribbean, North Africa, and the Middle East. In contrast, the prevalence remained comparatively low in Western Europe and East Africa. While diabetes prevalence increased in most countries, several high-income countries, including Japan and France, saw stable or declining trends in diabetes rates.

Furthermore, despite the rising prevalence of diabetes worldwide, improvements in treatment coverage were uneven. By 2022, 445 million adults with diabetes did not receive treatment, which was thrice the numbers observed in 1990. The highest treatment coverage was in South Korea, several high-income Western countries, and some Latin American and Middle Eastern nations.

In contrast, treatment coverage was notably low in sub-Saharan Africa and South Asia, with some African nations having treatment rates below 10%. This disparity suggests that low-resource regions are increasingly burdened by untreated diabetes, which further elevates the risk of cardiovascular disease and other complications. T

he study also highlighted that much of the untreated diabetes cases in low-income regions stemmed from undiagnosed cases, underscoring the need for improved screening and healthcare access.

Conclusions

Overall, the findings emphasized the growing global burden of diabetes, particularly in low-income regions with limited treatment access. The researchers stated that expanding healthcare coverage and diabetes management programs, especially in high-burden areas, are essential for reducing complications and improving health outcomes for individuals with diabetes worldwide.