Investigating the inverse association between glycaemia and abdominal aortic dilatation in a large Chinese hypertensive population: a cross-sectional study

Background: There is epidemiological evidence that diabetes has a protective effect on the occurrence and development of abdominal aortic aneurysms (AAAs). However, information on the role of glucose level on abdominal aortic diameter is limited. This study sought to assess the relationship between fasting plasma glucose (FPG) and infra-renal aortic diameter in a Chinese hypertensive population. Methods: The prospective participants comprised candidates from 2 large population-based studies on the clinical presentation and management of hypertension in China. In total, 18,034 hypertensive participants (6,942 male and 11,092 females, with a mean age of 64.72 +/- 7.41 years) were included in the study. The maximal diameter of the infra-renal aorta was measured by ultrasound scanning. Multivariate linear regression analyses were conducted to assess the specific association between FPG and abdominal aortic diameter. The interaction terms between the baseline covariables and the aortic diameter were used to determine if a variable affected the association between FPG and abdominal aortic diameter. Results: Of these, 22 cases of MA were identified, and the prevalence of diabetes was lower in those with AAA than thase without. A significant negative association was also found between FPG and aortic diameter in both sexes. A dose-dependent decrease in the prevalence of diabetes across quartiles of aortic diameter was also observed, with an estimated odds ratio (OR) of 0.60 (95% CI: 0.50-0.72) for men and 0.72 (95% CI: 0.63-0.82) for women for the top quartiles compared to the bottom quartiles. Cigarette smoking only interacted with the association between FPG level and aortic diameter in women. The association did not differ with other subgroups. Conclusions: Our findings indicate that glycaemia may plays a protective role in the early stage of aortic dilatation in both sexes in a Chinese hypertensive population. Prospective studies need to be conducted to confirm our findings and explore the mechanism underlying this association in different populations.