Researchers estimate that each additional decade of type 2 diabetes shortens lives by about 3.5 years compared to not having diabetes, based on data from studies conducted in 19 high-income countries.
They estimate that among 50-year-olds, life expectancy of those diagnosed with type 2 diabetes at age 30 is 14 years shorter than that of their peers without diabetes. Among those diagnosed at age 50, life expectancy is 6 years shorter.
The Emerging Risk Factors Collaboration study was recently published in The Lancet – Diabetes and Endocrinology.
The team analyzed data from the Emerging Risk Factors Collaboration and the UK Biobank. The data were from 97 long-term, prospective cohorts and involved 1.5 million participants who were followed for 23.1 million person-years.
“The strongest associations with earlier age at diagnosis of diabetes were for vascular (e.g., myocardial infarction and stroke) and other causes of death — mainly respiratory, neurological, and infectious diseases and external causes,” they report.
Their findings are consistent with previous studies that suggested that younger individuals who develop type 2 diabetes might have higher body mass index (BMI), blood pressure, and lipid levels and that they might experience faster deterioration in glycemic control than individuals who develop diabetes later, potentially leading to premature mortality.
When asked to comment, Anne Peters, MD, who was not involved with this study, said, “We’ve long known that diabetes reduces life expectancy, and the younger you get it, the more years you lose. However, this study was from a broader and larger population base than prior studies.” Peters is a Medscape contributor and the director of Clinical Diabetes Programs at the University of Southern California in Los Angeles.
“In this study, the major reason for death was vascular disease, and undertreatment of cardiovascular risk factors may have occurred in the younger individuals. We also don’t know about glucose control.
“I think the findings show that we should treat cardiovascular risk factors more aggressively in people diagnosed with [type 2] diabetes in their 30s and 40s,” urged Peters.
High Priority Should Be Given to Prevention Globally
“Type 2 diabetes used to be seen as a disease that affected older adults, but we’re increasingly seeing people diagnosed earlier in life,” senior author Emanuele Di Angelantonio, MD, PhD, from the University of Cambridge, explained in a press release. “As we’ve shown, they are at risk of a much shorter life expectancy than they would otherwise have.”
The findings suggest that “high priority should be given to developing and implementing interventions that prevent or delay the onset of [type 2 diabetes], especially as its prevalence among younger age groups is increasing globally,” urged the team.
The results “support the idea that the younger an individual is when they develop type 2 diabetes, the more damage their body accumulates from its impaired metabolism,” added co-senior author Naveed Sattar, MD, PhD, of the University of Glasgow,
Peters agrees: “People who develop type 2 diabetes at a younger age might have a different, potentially more aggressive type of type 2 diabetes and perhaps need treatment targets that are lower than people who develop type 2 diabetes when they are older.”
“The findings…suggest that early detection of diabetes by screening followed by intensive glucose management could help prevent long-term complications from the condition,” Sattar advised.
Peters added, “An issue for some is pregnancy.” She noted that “many of the medications taken for management of CVD [cardiovascular disease] risk factors are contraindicated in pregnancy (as are many of the medicines [for treating type 2 diabetes]).
“We need to be careful to risk reduce but take care of the ‘whole person,’ and if of childbearing age, consider the safest approaches to healthy management,” she emphasized.
Study Results: Type 2 Diabetes Diagnosed at Age 30, 40, and 50
Previous studies estimated that adults with type 2 diabetes die 6 years earlier on average in comparison with their counterparts who do not have diabetes. Still, it was not known how diabetes duration affects life span.
The team analyzed individual records from the Emerging Risk Factors Collaboration and the UK Biobank to investigate this.
The primary outcome was all-cause mortality. Other outcomes were deaths from CVD, cancer, and other causes.
Over a median follow-up of 12.5 years, there were 246,670 deaths: 84,443 from cardiovascular causes, 150,972 from noncardiovascular causes, and 11,255 from unknown/ill-defined causes.
Compared with participants who did not have a history of type 2 diabetes, the hazard ratios for all-cause mortality, adjusted for age and sex, were as follows:
2.69 for participants diagnosed at age 30 to 39;
2.26 for those diagnosed aged 40 to 49;
1.84 aged 50 to 59;
1.57 for those aged 60 to 69;
and 1.39 for those diagnosed 70 and older.
These hazard ratios were similar after adjusting for BMI, systolic blood pressure, and total cholesterol but were substantially attenuated after further adjusting for fasting glucose or A1c level.
Similar patterns were observed for cause-specific mortality.
“Every decade of earlier diagnosis of diabetes was associated with about 3–4 years of lower life expectancy, highlighting the need to develop and implement interventions that prevent or delay the onset of diabetes and to intensify the treatment of risk factors among young adults diagnosed with diabetes,” the researchers reiterate.