Obesity, subclinical myocardial injury, and incident heart failure

Objectives: The study sought to evaluate the association of obesity with a novel biomarker of subclinical myocardial injury, cardiac troponin T measured with a new high-sensitivity assay (hs-cTnT), among adults without clinical cardiovascular disease (CVD). Background: Laboratory evidence suggests a relationship between obesity and myocardial injury that mayplay a role in the development of heart failure (HF), but there is limited clinical data regarding this association. Methods: We evaluated 9,507 participants in the ARIC (Atherosclerosis Risk in Communities) study without baseline CVD (Visit 4, 1996 to 1999). We assessed the cross-sectional association of body mass index (BMI) with high (≥14 ng/l) and measurable (≥3 ng/l) hs-cTnT levels after multivariable regression. We further evaluated the independent and combined associations of BMI and hs-cTnT with incident HF. Results: Higher BMI was independently associated with a positive, linear increase in the likelihood of high hs-cTnT, with severe obesity (BMI >35 kg/m²) associated with an odds ratio of 2.20 (95% confidence interval: 1.59 to 3.06) for high hs-cTnT after adjustment. Over 12 years of follow-up, there were 869 incident HF events. Obesity and hs-cTnT were both independently associated with incident HF, and individuals with severe obesity and high hs-cTnT had a greater than 9-fold higher risk of incident HF (hazard ratio: 9.20 [95% confidence interval: 5.67 to 14.93]) than individuals with normal weight and undetectable hs-cTnT. Conclusions: Among individuals without CVD, higher BMI has an independent, linear association with subclinical myocardial injury, as assessed by hs-cTnT levels. Obesity and hs-cTnT provide independent and complementary prognostic information regarding the risk of incident HF.