U.S. cardiovascular mortality linked to diabetes reversed after years of decline
A nationwide CDC WONDER analysis captured a troubling turn in cardiovascular mortality among people with diabetes mellitus in the United States. From 1999 through 2020, 1,854,384 deaths were recorded in which cardiovascular disease was listed as the underlying cause and diabetes as a multiple cause of death, yielding an age-adjusted mortality rate of 25.06 per 100,000 population.
The broad arc initially moved in the right direction. Mortality declined significantly from 1999 to 2012, then flattened through 2018 before rising sharply again from 2018 to 2020. The final upswing was steep, with an annual percentage change of 6.94 during that interval. In a condition already shaped by chronic vascular injury, a late acceleration in deaths is not a subtle epidemiologic detail. It signals a reversal that demands explanation.
The mortality curve flattened, then turned upward
The investigators used death certificate data from CDC WONDER and identified cardiovascular deaths with ICD-10 codes I00–I99 as the underlying cause and diabetes codes E10–E14 as multiple causes of death. They calculated age-adjusted mortality rates using the 2000 US standard population and examined trends with Joinpoint regression. That framework is well suited to long-term surveillance because it can separate periods of decline, stability, and renewed growth rather than forcing the entire 21-year span into a single average trend.
Across the full study window, the early improvement was substantial. From 1999 to 2012, the annual percentage change was –2.64, reflecting a meaningful reduction in deaths. After that, mortality stabilized until 2018. The most concerning feature was the abrupt climb that followed. For a disease pair as tightly linked as diabetes and cardiovascular disease, a renewed rise may reflect multiple forces acting together: aging of the diabetic population, persistent gaps in blood pressure and lipid control, residual hyperglycemia, treatment access problems, and widening social inequities in prevention and acute care.
Disparities were concentrated by sex, race, and geography
The burden was not evenly distributed. Men had higher age-adjusted mortality rates than women. NH Black or African American individuals also experienced higher rates than other racial and ethnic groups, and residents of rural areas and Southern states faced a heavier burden than their urban and non-Southern counterparts. Oklahoma and Mississippi carried the highest state-level mortality rates.
These patterns fit the biology of vascular risk and the realities of care delivery. Diabetes accelerates atherosclerosis through endothelial dysfunction, oxidative stress, insulin resistance, and systemic inflammation, all of which can push coronary and cerebrovascular disease toward fatal outcomes. When those mechanisms operate in communities with reduced access to preventive services, fewer specialty resources, delayed diagnosis, and more fragmented chronic disease management, the mortality signal becomes sharper. Geographic clustering in the South and in rural areas suggests that place still shapes survival in a disease that is often treated as if physiology alone determines outcome.
One clear pattern stood out. Mortality did not simply rise evenly across the population.
Diabetes-associated cardiovascular death diverged from cardiovascular death alone
Trends for cardiovascular mortality among people with diabetes differed significantly from trends for cardiovascular mortality alone across all demographic strata, with p less than 0.05. That separation matters because it points to a diabetic population whose cardiovascular risk trajectory is not tracking the broader population in a uniform way. Even when cardiovascular mortality improves overall, the diabetes-associated subset can lag behind or reverse if metabolic control, preventive therapy, and structural access issues are not addressed in parallel.
For clinicians, the result is a reminder that diabetes is not merely a comorbidity in cardiovascular disease. It is a multiplier of risk. Hyperglycemia and insulin resistance alter plaque biology, impair vascular repair, and intensify the inflammatory milieu that drives coronary events. Over years, those processes can convert manageable cardiovascular risk into fatal disease, especially when compounded by hypertension, dyslipidemia, obesity, and delayed care. The death certificate data cannot identify which of these drivers dominated in any individual case, but the population trend strongly suggests that the combined burden remains incompletely controlled.
Why the late rise matters for prevention strategy
The late increase from 2018 to 2020 should push prevention efforts toward the settings where mortality is highest rather than toward broad, undifferentiated messaging. Rural communities, the Southern United States, and NH Black or African American populations emerged as the groups carrying the heaviest burden. Those findings argue for targeted screening, tighter control of cardiometabolic risk factors, and more reliable linkage to cardiovascular and diabetes care.
This is also a signal about timing in public health. The first decade-plus of decline showed that improvement is possible. The later rebound shows that progress can erode quickly when underlying disparities remain in place. If diabetes-related cardiovascular mortality is rising again after years of decline, then the standard approach of waiting for patients to declare themselves through acute events is too late. Prevention has to move upstream, into earlier control of glucose, blood pressure, and lipids, alongside efforts that improve access to consistent care and reduce regional gaps.
The study’s design supports surveillance, not causality. Death certificate data can misclassify diagnoses, and the analysis cannot determine which treatments patients received or how well risk factors were controlled. Even so, the pattern is large, persistent, and clinically credible. A mortality curve that falls for more than a decade and then turns upward in a high-risk subgroup is unlikely to be an artifact alone.
The most actionable question now is not whether diabetes increases cardiovascular risk. It clearly does. The harder question is why national mortality improved for years and then slipped backward so quickly, and which health-system failures are still driving excess deaths in the communities that can least absorb them.