Association between the atherogenic index of plasma and left ventricular hypertrophy in patients with obstructive sleep apnea: a retrospective cross-sectional study

Abstract

Background: The atherogenic index of plasma (AIP) is a simple and reliable marker of insulin resistance and is closely associated with various cardiovascular diseases (CVDs). However, the relationships between AIP and left ventricular (LV) geometric indicators have not been adequately assessed. This study was carried out to investigate the association between AIP and LV geometric abnormalities in obstructive sleep apnea (OSA) patients.

Methods: This retrospective cross-sectional study included a total of 618 OSA patients (57.3 ± 12.4 years, 73.1% males, BMI 28.1 ± 4.2 kg/m²) who underwent echocardiography. Patients with OSA were diagnosed with clinical symptoms and an apnea-hypopnea index ≥ 5.0. LV hypertrophy (LVH) was defined as left ventricular mass index (LVMI_h2.7) ≥ 50.0 g/m^2.7 for men and 47.0 g/m^2.7 for women. AIP was calculated as log₁₀ (TG/HDL-C).

Results: Compared with the non-LVH group, AIP was significantly higher in the LVH group (0.19 ± 0.29 vs 0.24 ± 0.28, P = 0.024) and the concentric LVH group (0.18 ± 0.29, 0.19 ± 0.30, 0.20 ± 0.26 and 0.29 ± 0.29 in the control, concentric remodeling, eccentric hypertrophy and concentric hypertrophy groups, respectively, P = 0.021). Meanwhile, in the group of patients with the highest AIP tertile, the levels of LVMI_h2.7 (42.8 ± 10.5, 43.2 ± 9.3 and 46.1 ± 12.1 in the T1, T2 and T3 groups, respectively, P = 0.003), and the prevalence of LVH (25.2%, 24.0% and 34.6% in the T1, T2 and T3 groups, respectively, P = 0.032) and concentric LVH (10.7%, 9.8% and 20.2% in the T1, T2 and T3 groups, respectively, P = 0.053) were higher compared with those in the other groups. Positive correlations between AIP and LV geometric indicators including the LVMI_h2.7, LVMI_BSA, LV mass (LVM), diastolic left ventricular inner diameter (LVIDd), diastolic left ventricular posterior wall thickness (PWTd) and diastolic interventricular septal thickness (IVSTd), were revealed according to correlation analysis (P < 0.05). Furthermore, AIP was independently associated with LVMI_h2.7 according to multivariate linear regression model (β = 0.125, P = 0.001). Notably, AIP remained independently associated with an elevated risk of LVH [odds ratio (OR) = 1.317 per 1 standard deviation (SD) increment, 95% confidence interval (CI): 1.058 - 1.639, P = 0.014) and concentric LVH (OR = 1.545 per 1 SD increment, 95% CI: 1.173 - 2.035, P = 0.002) after fully adjusting for all confounding risk factors by multivariate logistic regression analyses.

Conclusions: AIP was independently associated with an increased risk of LVH and concentric LVH in OSA patients. Therefore, AIP, as a practical and cost-effective test, might be useful in monitoring hypertrophic remodeling of the heart and improving CVDs risk stratification in clinical management of OSA.

Keywords: Atherogenic index of plasma; Insulin resistance; Left ventricular hypertrophy; Obstructive sleep apnea.

Fig. 1

Comparisons of AIP between the non-LVH and LVH groups (A) and between different LV geometric patterns (B). AIP, atherogenic index of plasma; LVH, left ventricular hypertrophy; LV, left ventricular

Fig. 2

Comparisons of the percentages of patients with LVH (A) and concentric LVH (B) according to tertiles of AIP. LVH, left ventricular hypertrophy; AIP, atherogenic index of plasma; T1, AIP < 0.07; T2, 0.07 ≤ AIP < 0.31; T3, AIP ≥ 0.31

Fig. 3

Forest plots of the risk of LVH (A) and concentric LVH (B) according to tertiles of AIP by the fully adjusted logistic regression model. LVH, left ventricular hypertrophy; AIP, atherogenic index of plasma; BMI, body mass index; OSA, obstructive sleep apnea; OR, odds ratio; CI, confidence interval; T1, AIP < 0.07; T2, 0.07 ≤ AIP < 0.31; T3, AIP ≥ 0.31