Am J Med: Microvascular disease burden and atrial fibrillation risk in adults with type 2 diabetes

Background: Atrial fibrillation is the most common persistent arrhythmia, and its prevalence is expected to double
by 2050.
People with type 2 diabetes have a significantly increased risk of atrial fibrillation, and they have a 40%
higher risk of developing atrial fibrillation than people without diabetes.
In people with diabetes, the diabetes risk of developing atrial fibrillation increases by 3%
for every year of life.
About 1 in 6 people with atrial fibrillation has diabetes; Diabetes is associated with
worsening symptoms of atrial fibrillation, reduced quality of life, and increased morbidity and mortality in patients with atrial fibrillation.
The exact mechanism between diabetes and greater risk of atrial fibrillation is not fully understood, but may involve diabetes-mediated maladaptation and prefibrillation structural, electrical, and microangiopathy
.
While animal studies suggest a possible link between microvascular dysfunction – a hallmark of diabetes – and atrial fibrillation, there are few
population-based studies assessing the impact of diabetes-associated microvascular disease and its burden on developing atrial fibrillation in people with type 2 diabetes.

Objective: Using data from the Action to Control Diabetes Cardiovascular Risk (ACCORD) study, we evaluated the association
between microvascular disease assessed in several vascular beds and the development of atrial fibrillation in a large number of patients with type 2 diabetes.
We hypothesized that the greater the burden of microvascular disease, the higher the risk of developing atrial fibrillation
.

Methods: A total of 7603 patients with type 2 diabetes without atrial fibrillation were assessed for diabetic nephropathy, retinopathy or neuropathy
at baseline.
A follow-up ECG is used to determine the occurrence of an atrial fibrillation event
.
Modified Poisson regression was used to analyse risk ratios (RR) and 95% confidence intervals (CI).

Results: Of the 7603 participants (mean age 62.
5 years, 38.
0% female, 63.
4% white), 63.
3% (n=4816) had microangiopathy – defined as the presence of ≥-1: diabetic nephropathy, retinopathy, or neuropathy
.
Over a median period of 7 years, there were 137 atrial fibrillation events (1.
8%)
.
Participants with microvascular disease had a 1.
9-fold risk of developing atrial fibrillation compared with participants without microvascular disease (RR 1.
88; 95% CI, 1.
20 to 2.
95).

Compared with no microangiopathy, the RRs for atrial fibrillation with 1 microangiopathy and ≥ 2 microangiopathy were 1.
6 2 (95% CI, 1.
0 1~2.
6 1) and 2.
47 (95% CI, 1.
4 6~4.
16),
respectively.
The relative risks of atrial fibrillation according to microangiopathy types for neuropathy, retinopathy and diabetic nephropathy were 1.
57 (95% CI, 1.
09~2.
26), 0.
95 (95% CI, 0.
53~1.
70) and 1.
67 (95% CI, 1.
15~2.
44),
respectively.

Table 1: Incidence and relative risk of atrial fibrillation by microvascular disease burden

Table 2: Incidence and relative risk of atrial fibrillation by type of microvascular disease

Conclusion: In adults with type 2 diabetes mellitus, the presence and burden of diabetic microvascular disease are independently correlated
with the risk of developing atrial fibrillation.

Kaze AD, Yuyun MF, Fonarow GC, et al.
Burden of Microvascular Disease and Risk of Atrial Fibrillation in Adults with Type 2 Diabetes.
Am J Med 2022 Sep; 135(9)