Global prevalence of older people living with type 1 diabetes mellitus jumped 180% in the past 30 years, a population-based study found.
This represents an increase from 1.3 million people worldwide in 1990 to 3.7 million in 2019, Yongze Li, MD, PhD, of First Hospital of China Medical University in Shenyang, and colleagues reported in .
After age standardization, the increase in global prevalence of type 1 diabetes for adults 65 and older was still 28% over the last three decades, rising from 400 to 514 per 100,000 population, with an average annual 0.86% increase (95% CI 0.79-0.93). In the U.S., the age-standardized prevalence increased from 956 to 1,488 per 100,000 population during the study timeframe, for an average annual 0.51% increase (95% CI 0.42-0.60).
These findings likely reflect a growing number of people with type 1 diabetes living to elderly age, noted Li and co-authors, and that the condition "is no longer a contributory factor in decreased life expectancy owing to improvements in medical care over the three decades."
"The findings are important for health practice and future research, and provide optimistic evidence for all people with T1DM [type 1 diabetes mellitus], especially those with a diagnosis at a young age," the researchers wrote.
Backing this theory up, Li's group found type 1 diabetes mortality significantly dropped by an average of 1% every year since 1990. The age-standardized mortality for those 65 and older decreased by 25% during this timeframe, from 4.7 to 3.5 per 100,000 population.
"These [mortality] findings may be related to recent achievements in development goals aimed at improving accessibility and coverage of healthcare services, as well as progress in economic growth, reduced poverty, and social protection efforts," Li's group pointed out.
They added that widespread adoption of insulin analogues plus greater use of insulin pumps likely contributed to these findings. "Although no cure exists for T1DM, the disease is manageable," they said.
In addition to reduced mortality, the disability-adjusted life years (DALYs) also dropped -- albeit at a slower rate than mortality. DALYs decreased on average 0.33% annually, from 113 to 103 per 100,000 population during the period from 1990 to 2019. DALYs represent the changes and reduction in disease burden if population-level exposure to a particular risk factor shifts, Li's group explained.
Throughout the study period, a high fasting plasma glucose level remained the largest DALY risk factor among older adults, suggesting that blood glucose control is "still suboptimal and a challenge" for these patients.
"Difficulties, such as adjustment and calculation of insulin sensitivity factors according to dietary patterns, become even more challenging for older people owing to changes in metabolism and other factors associated with ageing," the researchers noted. "On the other hand, doctors might prefer to deal with hyperglycemia rather than hypoglycemia when caring for older people with diabetes, because complications from hyperglycemia take longer to manifest than hypoglycemia, the latter leading to immediate adverse outcomes such as unconsciousness, falls, brain damage, and cardiovascular events."
To address this, they suggested older individuals aim for normoglycemia in a way that doesn't put them at risk for hypoglycemia through "active, but not tight" blood glucose control.
While DALYs from type 1 diabetes among older people significantly decreased across all sociodemographic subgroups, this wasn't the case in countries with a low-middle sociodemographic index. DALYs lost to the disease were highest in countries with a low sociodemographic index (141 per 100,000 population) and the lowest in countries with a high-middle sociodemographic index (86 per 100,000 population) in 2019.
Not surprisingly, countries with a high sociodemographic index had the largest decrease in type 1 diabetes mortality. On the other hand, middle sociodemographic index countries had the largest increase in type 1 diabetes prevalence among those 65 and older.
According to regions, the most rapid prevalence was observed in North Africa and the Middle East (average annual percentage change [AAPC] 2.40%), East Asia (2.17%), and western Europe (1.95%), and the slowest increase in prevalence was in North America (0.06%). However, all 21 regions across the globe experienced an increase in prevalence for those 65 and older.
When broken down by sex, prevalence increased for both men and women worldwide -- men from 0.6 to 1.7 million and women from 0.7 to 2 million -- though the increase was more rapid among men than among women (AAPC 1% vs 0.74%). While both sexes also had a drop in type 1 diabetes mortality during this time period, the reduction was smaller in men (AAPC -0.58% vs -1.29%).
As for age, the prevalence of type 1 diabetes at least tripled in every age subgroup of people 65 and older and even increased five- to six-fold among those over 90.
Li's group pulled cross sectional data from the Global Health Data Exchange for the analysis, which details the global burden of 369 diseases and injuries and 87 risk factors, including type 1 diabetes, across 21 regions and 204 countries and territories. Because of variations in health systems across countries, there might have been incomplete data or bias, Li's group highlighted.
Disclosures
The study was supported by the National Natural Science Foundation of China and the China Postdoctoral Science Foundation.
Li and co-authors reported no disclosures.
Primary Source
The BMJ
Yang K, et al "Global burden of type 1 diabetes in adults aged 65 years and older, 1990-2019: population based study" BMJ 2024; DOI: 10.1136/ bmj‑2023‑078432.