The longitudinal association of adipose-to-lean ratio with incident cardiometabolic morbidity: The CARDIA study

Aim: To assess the association of adipose-to-lean ratio (ALR) with incident type 2 diabetes mellitus (T2DM), hypertension, and dyslipidemia in middle adulthood. Method: Black and White Coronary Artery Risk Development in Young Adults participants without T2DM, hypertension, or dyslipidemia in 2005 - 06 (baseline) were included. Baseline adipose and lean mass were assessed via dual-energy X-ray absorptiometry. ALR was calculated as adipose divided by lean mass and then standardized within sex strata. Single time-point incident morbidity was assessed every five years from baseline through 2016. Cox proportional hazards regression was used to estimate hazard ratios (HR) for morbidity over 10 years per 1SD increment in ALR adjusted for cardiovascular risk factors. Result: The cumulative incidence of T2DM was 7.9 % (129 events/ N = 1643; 16,301 person-years), 26.7 % (485 events/ N = 1819; 17,895 person-years) for hypertension, and 49.1 % (435 events/ N = 855, 8089 person-years) for dyslipidemia. In the adjusted models, ALR was positively associated with a risk of T2DM (HR [95 % CI]; 1.69 [1.31, 2.19]) and hypertension (1.23 [1.08, 1.40]). There was no significant interaction between ALR and sex for any morbidity. Conclusion: ALR in middle adulthood is associated with incident T2DM and hypertension. The extent to which localized body composition measures might inform morbidity risk merits further investigation.