Diabetics are less likely to develop thoracic aortic dissection: a 10-year single-center analysis.

Background: Diabetes mellitus (DM) is an acknowledged risk factor for atherosclerosis, and diabetics are more likely to have hypertension. Atherosclerosis and hypertension are risk factors for aortic dissection. However, recent studies have shown that DM is associated with changes in aortic wall collagen. In this retrospective study we assess the relationship between DM and thoracic aortic dissection (TAD).

Methods: Patients with a diagnosis of thoracic aortic dissection during the last 10 years were identified from our hospital records. The prevalence of DM in Stanford type A and B TAD was compared with that of two age- and gender-matched control groups. For every diabetic dissection case, 10 controls were selected from the hospital data.

Results: Two hundred nineteen patients (median age 61 years, male:female ratio 145:74) were identified with TAD, comprising 131 type A dissections and 88 type B dissections. Only 3 of 131 (2.3%) type A aortic dissections were diabetics, whereas, in control group 1, 241 of 1310 (18.4%) were diabetics and, in control group 2, 116 of 1310 (8.9%) were diabetics [odds ratios: 0.1 (0.03-0.32) and 0.24 (0.07-0.76), respectively] (P = 0.0001 and 0.007, respectively). Similarly, only 2 of 88 (2.3%) type B aortic dissections were diabetics, whereas 228 of 880 (26.0%) and 102 of 880 (11.6%) were diabetics in groups 1 and 2 [odds ratios: 0.07 (0.02-0.27) and 0.18 (0.04-0.73), respectively] (P = 0.0001 and 0.0035, respectively). All these odds ratios were statistically significant (P < 0.01).

Conclusions: Patients with thoracic aortic dissection are less likely to be diabetic. Although we identified association only, not causality, it is possible that DM, or its treatment, has a protective effect against aortic dissection.