Apolipoprotein E Gene Polymorphism, Glycated Hemoglobin, and Peripheral Arterial Disease Risk in Chinese Type 2 Diabetic Patients

Involvement of APOE in Incidence of Revascularization in Patients Affected by Peripheral Arterial Disease: A Prospective Study from Southern Italy

INTRODUCTION

Atherosclerosis is a complex multifactorial disease and apolipoprotein E (APOE) polymorphism has been associated with cardiovascular events. The APOE gene, located on chromosome 19q13.2, has an important role in lipid metabolism, in particular on circulating cholesterol levels, implying further pleiotropic effects; from its polymorphism are derived three alleles (ε2, ε3 and ε4), which induce different phenotypes, while its impact on carotid and femoral atherosclerosis is still controversial.

OBJECTIVES

The aim of the study is to investigate the relationship between APOE genotypes and peripheral revascularization in a cohort of patients affected by advanced peripheral arterial disease (PAD) at a prolonged follow-up.

MATERIALS AND METHODS

Some 332 patients (259 males and 73 females; mean age 70.86 ± 7.95 years) with severe PAD were enrolled in a longitudinal study, with a 90.75 ± 32.25 month follow-up, assessing major adverse cardiovascular events (MACE).

RESULTS

As compared with ε3/ε3, in ε4 patients we observed a significant higher incidence of carotid (13.2% vs. 5.6%; HR = 2.485, 95% CI 1.062-5.814; p = 0.036) and lower limb (11.8% vs. 4.3%; HR = 2.765, 95% CI 1.091-7.008; p = 0.032) revascularizations and, accordingly, a higher incidence of total peripheral revascularizations (13.5% vs. 9.5%; HR = 2.705, 95% CI 1.420-5.151; p = 0.002). HR remained statistically significant even when adjusted for classic cardiovascular risk factors.

CONCLUSIONS

In our observational study, we confirm that the ε4 allele is associated with higher total peripheral revascularization in patients with advanced atherosclerotic vascular disease at prolonged follow-up.

Correlation Between ApoE Gene Polymorphism and LEAD in Patients with T2DM That are of Han Nationality in Northern China

To investigate the correlation between ApoE gene polymorphism and the risk of lower extremity arterial disease (LEAD) in T2DM patients of Han nationality in northern China. One hundred and fifty patients with T2DM and 150 patients with T2DM combined with LEAD were enrolled in the study and assigned to the control group and the case group, respectively. The results revealed that the number of epsilon 2 (ε2) genotype carriers in the case group was significantly lower than that in the control group (case vs control: 8.0% vs 15.4%), and the distribution of the ε2 allele frequency was similar to that of the genotype (case vs control: 4.0% vs 8.4%). A binary logistic regression analysis revealed that age, waist-to-hip ratio (WHR), and gender were risk factors for T2DM with LEAD and that the ApoE ε2 carriers was a protective factor (odds ratio [OR] 0.380; 95% confidence interval [CI] 0.162-0.892; P = .026). In male subjects, ε2 carriers were more common in the control group (case vs control:7.8% vs 24.1%), while epsilon 4 (ε4) carriers were more common in the case group (case vs control: 23.3% vs 8.6%); the distribution of frequency of ε2 and ε4 alleles was more common in the control group and the case group, respectively (case vs control: 3.9% vs 12.1%, 12.8% vs 5.2%). In male, age and WHR were risk factors for the disease, and being an ε2 carrier was a protective factor. Being an ApoE gene ε2 carrier is a protective factor for LEAD in male patients with T2DM that are of Han nationality in northern China.

Vitamin D Deficiency May Not Be an Independent Risk Factor for Peripheral Arterial Disease in Middle-Aged and Elderly Patients with Type 2 Diabetes in China

Background

Vitamin D deficiency can lead to the increased severity and prevalence of metabolic disorders. However, the relationship between levels of 25-hydroxyvitamin D (25(OH)D) and peripheral arterial disease (PAD) is controversial. Therefore, the purpose of our study was to explore the relationship between 25(OH)D levels and PAD in middle-aged and elderly type 2 diabetes mellitus (T2DM) patients in China.

Methods

In this study, a total of 183 patients with T2DM were enrolled and categorized into groups with or without PAD. Clinical and biochemical parameters were assessed, and a Pearson analysis was used to identify a possible association between levels of 25(OH)D and glycated hemoglobin (HbA1c). Some biochemical parameters were also assessed in the T2DM patients with PAD according to vitamin D status. Interactions were also explored among HbA1c control, 25(OH)D levels, and PAD. The possible risk factors for PAD were measured by multivariable logistic regression analyses.

Results

Firstly, the parameters including age, HbA1c, and disease duration between T2DM and T2DM+PAD groups showed significantly different. In addition, the frequency of smoking in the group of T2DM patients was significantly less than that in the T2DM patients with the PAD group, while the frequency of well-controlled HbA1c in the patients with T2DM was significantly higher. There is a trend that the levels of 25(OH)D and HbA1c are correlated, but no interactions among vitamin D deficiency, HbA1c control, and PAD were found. However, HbA1c significantly differed between groups with vitamin D deficiency and insufficiency in the T2DM patients with PAD. According to the multivariate logistic regression analyses, the PAD risk factors of T2DM patients were family history of diabetes, smoking, age, disease duration, HbA1c, and LDL.

Conclusions

The findings demonstrate that the deficiency of vitamin D level is not related to PAD, but HbA1c may be linked to the presence of PAD in middle-aged and elderly patients with T2DM in China.