Association of adiponectin with left ventricular mass in blacks: the Jackson Heart Study

Abstract

Background: Blacks have a higher prevalence of left ventricular hypertrophy than whites. Several population-based studies have reported an inverse association between adiponectin and left ventricular mass (LVM); however, the relationship between adiponectin levels and LVM has yet to be defined in blacks. The Jackson Heart Study cohort provides an opportunity to test the hypothesis that the inverse association between adiponectin and LVM may be modified by risk factors common among blacks.

Methods and results: The study population included 2649 black Jackson Heart Study participants (mean age 51±12 years, 63% women, 51% obese, 54% with hypertension, and 16% with diabetes). Multiple linear and spline regression was used to assess the association, with adjustment for demographic, clinical, and behavioral covariates. Among all the participants, there was a statistically significant but modest inverse association between adiponectin and LVM index. Hypertension and insulin resistance emerged as statistically significant effect modifiers of this relationship. The inverse association present among the normotensive participants was explained by obesity measures such as the body mass index. Among participants with both hypertension and insulin resistance, there was a significant direct association between adiponectin and the LVM index after multivariable adjustment (β=1.55, P=0.04, per 1-SD increment in the adiponectin log value).

Conclusions: The association between serum adiponectin and LVM among blacks in the Jackson Heart Study cohort was dependent on hypertension and insulin resistance status. Normotensive blacks exhibited an inverse adiponectin-LVM association, whereas participants with hypertension and insulin resistance had a direct association.

Figure 1. The relationship between adiponectin* and left ventricular mass index† by spline regression modeling‡ among participants without hypertension (N = 1,206)

*Adiponectin was log-transformed from units expressed as μg/mL (in order to have logarithmic values above the unit); †Multivariable-adjusted values (residuals) of left ventricular mass index (LVMI); ‡ Adjustment was performed for age, sex, BMI, alcohol drinking, HDL-cholesterol, triglycerides and HOMA-IR (log-transformed).

Figure 2. The relationship between adiponectin* and left ventricular mass index† by spline regression modeling‡ among participants with hypertension and insulin resistance (N = 331)

*Adiponectin was log-transformed from units expressed as μg/mL (in order to have logarithmic values above the unit); †Multivariable-adjusted values (residuals) of left ventricular mass index (LVMI); ‡ Adjustment was performed for age, sex, BMI, alcohol drinking, HDL-cholesterol and triglycerides.