Reduced Incidence of Severe Coronary Atherosclerosis in Obese Subjects With Type 2 Diabetes – An Obesity Paradox?

Abstract

An obesity paradox wherein a lower incidence of cardiovascular (CV) morbidity and mortality is seen in overweight/ obese patients compared with patients with a ‘normal’ body mass index (BMI) has been reported in patients with type 2 diabetes mellitus (T2DM). We evaluated the relationship between BMI and coronary atherosclerosis in a cohort of subjects with T2DM who were asymptomatic for CV disease using computed tomography coronary angiography. Subjects were followed up for a composite endpoint of all-cause death, non-fatal myocardial infarction or late coronary artery revascularisation. Of the 258 patients enrolled, 226 were eligible for follow-up over a median of 22.8 months. In patients with a normal BMI (<25 kg/m2), 53% had ≥1 significantly stenotic plaque compared with 26% of patients with a BMI >30 kg/m2 at baseline. Subjects with a BMI ≥35 kg/m2 were 82% less likely to present with significant coronary artery plaque at baseline compared with those with a BMI <25 kg/m2 (p=0.01). The risk of a composite CV endpoint event in the overweight/obese group (>25 kg/m2) was approximately 70% lower than in subjects with normal weight. In conclusion, higher BMI may be associated with a lower prevalence of coronary atherosclerosis in patients with T2DM.