Type 2 Diabetes Accelerates Clinical Progression of Aortic Stenosis, Nationwide Swedish Study Finds

Type 2 diabetes (搜索)搜索该疾病 is associated with faster clinical progression of aortic stenosis (搜索)搜索该疾病, according to a nationwide retrospective cohort study from Sweden involving more than 47,000 patients. Researchers linked Swedish healthcare registries to identify 16,116 individuals with both type 2 diabetes and incident aortic stenosis and compared them with 31,066 matched patients with aortic stenosis but without diabetes, with follow-up extending up to 18 years.

The study, published in Scientific Reports, examined whether incident aortic stenosis (搜索)搜索该疾病 progresses differently in unselected patients with and without diabetes. As global life expectancy and obesity rates rise, the prevalence of both degenerative aortic stenosis and type 2 diabetes (搜索)搜索该疾病 mellitus is increasing, resulting in an expanding population of individuals living with both conditions.

Study Design and Population

Using data from the Swedish National Diabetes Register (搜索)搜索该词条 (NDR), which covers approximately 90% of patients with type 2 diabetes (搜索)搜索该疾病 in Sweden, the investigators identified a cohort of 569,895 patients with type 2 diabetes. After excluding individuals with aortic stenosis (搜索)搜索该疾病 at baseline, 16,116 individuals with incident aortic stenosis were selected as cases. These were individually matched by sex, age, and region with five non-diabetic comparators with aortic stenosis, yielding 31,066 controls and a total of 47,182 individuals with aortic stenosis.

Patients with diabetes were younger (mean age 70.7 years vs 72.0 years), more likely to be male, and carried a greater burden of comorbidities at baseline. The mean duration of diabetes was close to six years, with a mean age of onset of 64 years. The median HbA1C was 51 mmol/mol, and 55% of cases had good glycemic control.

Clinical Progression and Outcomes

Clinical progression was defined as progression from aortic stenosis (搜索)搜索该疾病 diagnosis to heart failure (搜索)搜索该疾病 hospitalization, aortic valve replacement, mortality, or a composite endpoint incorporating these outcomes. Over follow-up of up to 18 years, patients with type 2 diabetes (搜索)搜索该疾病 experienced poorer outcomes across all measured endpoints than comparators without diabetes.

Overall, 63.9% of patients with diabetes reached the composite outcome compared with 58.5% of controls, corresponding to an incidence rate of 235.9 per 1000 person-years in cases versus 215.9 per 1000 person-years in comparators. Specifically, 48.2% of cases died (27.2% from cardiovascular causes), compared with 43.3% and 25.0% respectively among comparators. Patients with diabetes more often underwent transcatheter or surgical aortic valve replacement (6.6% vs 5.1% for TAVR; 15.5% vs 14.1% for SAVR) and were hospitalized with incident heart failure (搜索)搜索该疾病 at higher rates (23.3 vs 20.0 per 1000 person-years).

Adjusted Risk Estimates

After adjusting for age, education, and comorbidities, patients with diabetes had a 10% higher hazard of death (95% CI 1.06–1.13), a 32% higher hazard of hospitalization for heart failure (搜索)搜索该疾病 (95% CI 1.23–1.42), an 18% higher hazard of undergoing TAVR/SAVR (95% CI 1.13–1.23), and a 10% higher hazard of the composite outcome (95% CI 1.07–1.13).

However, after further adjustment for medications, no excess mortality risk was observed among cases compared with comparators. The disparity in hospitalization for heart failure (搜索)搜索该疾病, aortic valve replacement, and the composite outcome persisted, with cases having a 14% higher hazard for heart failure hospitalization (95% CI 1.03–1.26), an 11% higher hazard for aortic valve replacement (95% CI 1.04–1.18), and a 4% higher hazard for the composite outcome (95% CI 1.01–1.08).

In Cox proportional hazards analysis, type 2 diabetes (搜索)搜索该疾病 alone remained a predictive factor for aortic valve replacement (HR 1.11, 95% CI 1.04–1.18) and heart failure (搜索)搜索该疾病 hospitalization (HR 1.14, 95% CI 1.03–1.26), but not for all-cause mortality (HR 1.00, 95% CI 0.96–1.05).

Interpretation and Clinical Implications

The researchers noted that the unadjusted mortality difference was attenuated after adjustment for comorbidities and medications, and should be interpreted cautiously as it may reflect differences in baseline risk profile, treatment patterns, and residual confounding rather than a specific survival benefit of antidiabetic therapy.

"Diabetes may contribute to a less favourable clinical course after aortic stenosis (搜索)搜索该疾病 diagnosis, even when mortality differences are not apparent," the authors wrote. The findings suggest that patients with both type 2 diabetes (搜索)搜索该疾病 and aortic stenosis may require increased clinical awareness during follow-up.

The higher risk of heart failure (搜索)搜索该疾病 hospitalization in patients with type 2 diabetes (搜索)搜索该疾病 could be interpreted as reflecting a more unfavourable clinical trajectory after aortic stenosis (搜索)搜索该疾病 diagnosis, rather than accelerated valvular progression alone.

Study Limitations

The authors acknowledged several important limitations. Most significantly, the study lacked echocardiographic data on the initial severity of the valve lesion and valve morphology, preventing assessment of whether patients with diabetes had more advanced disease at baseline. Because aortic valve replacement indication is determined by symptoms and severity rather than the presence of diabetes, the observed increased hazard may stem from more advanced valvular disease within the diabetic population.

Additional limitations included reliance on ICD-code-based diagnoses without validation, the absence of risk factor and laboratory data for the control group, and the fact that individuals were included between 2001 and 2019, meaning glucose-lowering treatment patterns largely reflect an earlier therapeutic era with limited use of SGLT2 inhibitors (搜索)搜索该药品 and GLP-1 receptor agonists (搜索)搜索该药品. The authors also noted potential surveillance and lead-time bias, as individuals with type 2 diabetes (搜索)搜索该疾病 may have more frequent healthcare contacts and may be diagnosed with aortic stenosis (搜索)搜索该疾病 earlier or under different clinical circumstances.

Despite these limitations, the authors concluded that the findings remain clinically relevant, as individuals with type 2 diabetes (搜索)搜索该疾病 still had a less favourable clinical course after a recorded diagnosis of aortic stenosis (搜索)搜索该疾病.