The relationship between adiponectin and left ventricular mass index varies with the risk of left ventricular hypertrophy

Abstract

Background: Adiponectin directly protects against cardiac remodeling. Despite this beneficial effect, most epidemiological studies have reported a negative relationship between adiponectin level and left ventricular mass index (LVMI). However, a positive relationship has also been reported in subjects at high risk of left ventricular hypertrophy (LVH). Based on these conflicting results, we hypothesized that the relationship between serum adiponectin level and LVMI varies with the risk of LVH.

Methods: A community-based, cross-sectional study was performed on 1414 subjects. LVMI was measured by echocardiography. Log-transformed adiponectin levels (Log-ADPN) were used for the analysis.

Results: Serum adiponectin level had a biphasic distribution (an increase after a decrease) with increasing LVMI. Although Log-ADPN did not correlate with LVMI, Log-ADPN was modestly associated with LVMI in the multivariate analysis (β = 0.079, p = 0.001). The relationship between adiponectin level and LVMI was bidirectional according to the risk of LVH. In normotensive subjects younger than 50 years, Log-ADPN negatively correlated with LVMI (r = -0.204, p = 0.005); however, Log-ADPN positively correlated with LVMI in ≥50-year-old obese subjects with high arterial stiffness (r = 0.189, p = 0.030). The correlation coefficient between Log-ADPN and LVMI gradually changed from negative to positive with increasing risk factors for LVH. The risk of LVH significantly interacted with the relationship between Log-ADPN and LVMI. In the multivariate analysis, Log-ADPN was associated with LVMI in the subjects at risk of LVH; however, Log-ADPN was either not associated or negatively associated with LVMI in subjects at low risk of LVH.

Conclusion: Adiponectin level and LVMI are negatively associated in subjects at low risk of LVH and are positively associated in subjects at high risk of LVH. Therefore, the relationship between adiponectin and LVMI varies with the risk of LVH.

Figure 1. The adiponectin level and LVMI according to the severity of LVH.

The bars and whiskers indicate the means and standard deviations. * Subjects without hypertension, obesity (body mass index ≥25 kg/m²), impaired fasting glucose and LVH. LVMI increases with the severity of LVH. Adiponectin in the healthy subjects is higher than in subjects without LVH, whereas adiponectin in subjects without LVH is lower than in subjects with moderate to severe LVH. LVMI, left ventricular mass index; LVH, left ventricular hypertrophy.

Figure 2. Variations in the correlation between LVMI and Log-ADPN according to the risk of LVH.

* p<0.05. † The highest quartile for the brachial-ankle pulse wave velocity. ‡ BMI ≥25 kg/m². Log-ADPN is centered around the mean. The direction of the correlations between adiponectin level and LVMI gradually changes from negative to positive with the number of LVH risk factors in both scoring methods. LVMI, left ventricular mass index; Log-ADPN, log-transformed adiponectin; LVH, left ventricular hypertrophy.