Progression of aortic stenosis in patients with diabetes mellitus type 2 compared with matched controls
Authors: Kontogeorgos S M , Rosengren A , Zverkova Sandstrom T , Lindgren M 
Published: October 2024

Abstract

Background
Degenerative aortic stenosis (AS) and diabetes mellitus type 2 (DM) increase with age1,2 and their prevalence is expected to rise. Patients with DM have a higher risk to develop AS3 and the pathophysiological process leading from a normal aortic valve to AS involves factors associated with DM. AS develops over years, but it can evolve more rapidly. There is insufficient knowledge about risk factors for rapid progression in AS and monitoring strategies among patients at high risk for rapid progression.
The aim of this project is to evaluate the AS progression towards combined outcome (incident heart failure, death, need for intervention) in patients with type 2 DM compared with matched controls.

Methods
From the Swedish National Diabetes Register (NDR) we identified all patients with type 2 DM between 01-01-2001- 31-12-2019 and for each patient 5 controls (matched for age, sex, region) from the Swedish Total Population Register. Afterwards we identified a cohort of individuals with AS from these two groups, by linking the NDR with the National Patient Register. The outcomes were: all- cause and cardiovascular mortality, and combined outcome (mortality, hospitalization for heart failure (HF) or aortic valve replacement (AVR)). We used Kaplan Meier survival curves to detect differences in all-cause mortality, cardiovascular mortality, time until AVR and combined outcome between cases and controls. Cox proportional hazards model adjusted for sex, age, obesity, renal failure, hyperparathyroidism, hypertension, hyperlipidemia was used to study the risk difference between the cases and controls for the combined outcome.

Results
We identified 16 144 individuals with type 2 DM and AS and 31 206 matched controls. The individuals with type 2 DM were predominately men (59% vs 53%), younger (mean age 70.6 vs 71.9), and had more comorbidities. In unadjusted analysis they were hospitalized for HF more often (8.2% vs 6.8%) and more often underwent AVR (surgically) (22.0% vs 19.0%) or transcatheter(6.6% vs 5.0%).
Patients with AS and DM had higher all-cause and cardiovascular mortality and faster progression towards death, AVR or hospitalization for HF (see figure 1, A, B, C). The progression to AVR was significant, although the difference was small and not clinically relevant (plot D).
In the adjusted model, the patients with AS and DM had 13% higher hazard to have the combined outcome compared with controls (see figure 2). Sex (female), hypertension and hyperlipidemia lowered the hazard for the combined event, while obesity, hyperparathyroidism and renal failure increased the hazard for the combined event.

Conclusions
Patients with concomitant AS and DM seem to have faster progression towards death (both all-cause and cardiovascular), and heart failure hospitalization or AVR compared with patients with AS without DM. Therefore, it might be appropriate to be more active regarding follow-up and intervention in these patients.Kaplan Meirer curvesForest plot for adjusted Cox model