New Review Details Mortality Rates in Diabetics Since 1970

A diabetic patient checking their glucose levels.

Data from an analysis of nearly 3 dozen studies are providing clinicians a comprehensive overview of trends in all-cause mortality among diabetic patients over the last half-century.

Conducted by an international team of physicians representing the US, the United Kingdom, and Australia, results of the systematic review detail mortality trends in patients with diabetes across multiple population subgroups from 17 countries between 1970-2016.

“Examining mortality trends is crucial for understanding the health burden associated with diabetes. Our data provide important context to concurrent changes in the prevalence of diabetes. Indeed, the falling mortality in a number of settings reported here will likely lead to increasing prevalence despite a stable or even declining incidence of diabetes,” wrote study investigators.

Few diseases have received as much attention and become as prominent as diabetes in the past several decades. In the US and abroad, prevalence of diabetes has skyrocketed, but recent advances in therapies and care have drastically improved disease management. In an effort to quantify and further examine how this relationship has impacted mortality in these patients, investigators performed a systematic review of studies reporting all-cause mortality rates across 2 or more time periods in patients with diabetes.

Using the MEDLINE, EMBASE, and CINAHL database, investigators conducted a search for articles published from 1980-2019. For inclusion, studies needed to be observational in nature, report all-cause mortality rates in diabetics in 2 or more separate time periods, and be published in English.

In total, 30,295 articles were screened and 35 met inclusion criteria. From these 35 studies, which contained information from patients in 17 countries, investigators obtained data on 69 separate ethnic-specific or sex-specific diabetic populations dating back to 1970.

For the purpose of analysis, investigators defined ethnic classes as Europid and non-Europid populations, based on the dominant ethnicity of the country where the study was conducted. Investigators also treated 4 age groups to examine age-specific mortality rates during each time period—defined as less than 40 years, 40-54 years, 55-69 years, and 70 or more years of age.

For studies examining time periods between 1970-1989, declines in all-cause mortality rate were observed in 43% of diabetic populations. In comparison, declines in mortality rate were observed in 53% and 74% of diabetic populations examined between 1990–1999 and 2000–2016, respectively.

When assessing more recent trends, investigators found mortality rates declined in 75% and 78% of predominantly Europid populations between 1990-1999 and 2000-2016, respectively. In contrast, declines were observed in 14% and 57% of non-Europid populations during those respective time periods.

When assessing mortality rates across age, declines were observed 33%, 65%, 88%, and 76% of diabetic populations less than 40 years, 40-54 years, 55-69 years, and 70 or more years of age, respectively, in studies examining time periods between 2000-2016. Additionally, investigators highlighted 60% of the diabetic populations examined between 1990-1999 and 58% examined between 2000–2016 experienced annual reductions in all-cause mortality rates similar to or greater than declines in those without diabetes when assessing studies with separate mortality data for those with and without diabetes.

Investigators noted multiple limitations within their study. Among the limitations listed by investigators were variation in the definition of diabetes among studies, the possibility of bias, and a lack of estimates relating to mortality trends in patients with diabetes in low- or middle-income countries.

This study, “A systematic review of trends in all-cause mortality among people with diabetes,” was published in Diabetologia.