Apolipoprotein E-ε2 and Resistance to Atherosclerosis in Midlife: The PESA Observational Study.

BACKGROUND: APOE is a known genetic contributor to cardiovascular disease, but the differential role APOE alleles play in subclinical atherosclerosis remains unclear. METHODS: The PESA (Progression of Early Subclinical Atherosclerosis) is an observational cohort study that recruited 4184 middle-aged asymptomatic individuals to be screened for cardiovascular risk and multiterritorial subclinical atherosclerosis. Participants were APOE-genotyped, and omics data were additionally evaluated. RESULTS: In the PESA study, the frequencies for APOE -ε2, -ε3, and -ε4 alleles were 0.060, 0.844, and 0.096, respectively. This study included a subcohort of 3887 participants (45.8±4.3 years of age; 62% males). As expected, APOE-ε4 carriers were at the highest risk for cardiovascular disease and had significantly greater odds of having subclinical atherosclerosis compared with ε3/ε3 carriers, which was mainly explained by their higher levels of low-density lipoprotein (LDL)-cholesterol. In turn, APOE-ε2 carriers were at the lowest risk for cardiovascular disease and had significantly lower odds of having subclinical atherosclerosis in several vascular territories (carotids: 0.62 [95% CI, 0.47-0.81]; P=0.00043; femorals: 0.60 [0.47-0.78]; P=9.96×10-5; coronaries: 0.53 [0.39-0.74]; P=0.00013; and increased PESA score: 0.58 [0.48-0.71]; P=3.16×10-8). This APOE-ε2 atheroprotective effect was mostly independent of the associated lower LDL-cholesterol levels and other cardiovascular risk factors. The protection conferred by the ε2 allele was greater with age (50-54 years: 0.49 [95% CI, 0.32-0.73]; P=0.00045), and normal (<150 mg/dL) levels of triglycerides (0.54 [0.44-0.66]; P=4.70×10-9 versus 0.90 [0.57-1.43]; P=0.67 if ≥150 mg/dL). Omics analysis revealed an enrichment of several canonical pathways associated with anti-inflammatory mechanisms together with the modulation of erythrocyte homeostasis, coagulation, and complement activation in ε2 carriers that might play a relevant role in the ε2's atheroprotective effect. CONCLUSIONS: This work sheds light on the role of APOE in cardiovascular disease development with important therapeutic and prevention implications on cardiovascular health, especially in early midlife. REGISTRATION: URL: https://www.clinicaltrials.gov: NCT01410318.

Early insulin resistance in normoglycemic low-risk individuals is associated with subclinical atherosclerosis.

BACKGROUND: Elevated glycated hemoglobin (HbA1c) is associated with a higher burden of subclinical atherosclerosis (SA). However, the association with SA of earlier insulin resistance markers is poorly understood. The study assessed the association between the homeostatic model assessment of insulin resistance index (HOMA-IR) and SA in addition to the effect of cardiovascular risk factors (CVRFs) in individuals with normal HbA1c. METHODS: A cohort of 3,741 middle-aged individuals from the Progression of Early Subclinical Atherosclerosis (PESA) study with basal HbA1c < 6.0% (< 42 mmol/mol) and no known CV disease underwent extensive imaging (multiterritorial vascular ultrasound and coronary artery calcium score, CACS) to assess the presence, burden, and extent of SA. RESULTS: Individuals with higher HOMA-IR values had higher rates of CVRFs. HOMA-IR showed a direct association with the multiterritorial extent of SA and CACS (p < 0.001) and with global plaque volume measured by 3-dimensional vascular ultrasound (p < 0.001). After adjusting for key CVRFs and HbA1c, HOMA-IR values ≥ 3 were associated with both the multiterritorial extent of SA (odds ratio 1.41; 95%CI: 1.01 to 1.95, p = 0.041) and CACS > 0 (odds ratio 1.74; 95%CI: 1.20 to 2.54, p = 0.004), as compared with the HOMA-IR < 2 (the reference HOMA-IR category). In a stratified analysis, this association remained significant in individuals with a low-to-moderate SCORE2 risk estimate (75.6% of the cohort) but not in high-risk individuals. CONCLUSIONS: The use of HOMA-IR identified low-risk individuals with a higher burden of SA, after adjusting for the effects of key traditional CVRFs and HbA1c. HOMA-IR is a simple measure that could facilitate earlier implementation of primary CV prevention strategies in clinical practice.

Association between subclinical atherosclerosis burden and unrecognized myocardial infarction detected by cardiac magnetic resonance in middle-aged low-risk adults.

AIMS: Evidence on the association between subclinical atherosclerosis (SA) and cardiovascular (CV) events in low-risk populations is scant. To study the association between SA burden and an ischaemic scar (IS), identified by cardiac magnetic resonance (CMR), as a surrogate of CV endpoint, in a low-risk population. METHODS AND RESULTS: A cohort of 712 asymptomatic middle-aged individuals from the Progression of Early SA (PESA-CNIC-Santander) study (median age 51 years, 84% male, median SCORE2 3.37) were evaluated on enrolment and at 3-year follow-up with 2D/3D vascular ultrasound (VUS) and coronary artery calcification scoring (CACS). A cardiac magnetic study (CMR) was subsequently performed and IS defined as the presence of subendocardial or transmural late gadolinium enhancement (LGE). On CMR, 132 (19.1%) participants had positive LGE, and IS was identified in 20 (2.9%) participants. Individuals with IS had significantly higher SCORE2 at baseline and higher CACS and peripheral SA burden (number of plaques by 2DVUS and plaque volume by 3DVUS) at both SA evaluations. High CACS and peripheral SA (number of plaques) burden were independently associated with the presence of IS, after adjusting for SCORE2 [OR for 3rd tertile, 8.31; 95% confidence interval (CI) 2.85-24.2; P < 0.001; and 2.77; 95% CI, 1.02-7.51; P = 0.045, respectively] and provided significant incremental diagnostic value over SCORE2. CONCLUSION: In a low-risk middle-aged population, SA burden (CAC and peripheral plaques) was independently associated with a higher prevalence of IS identified by CMR. These findings reinforce the value of SA evaluation to early implement preventive measures. CLINICAL TRIAL REGISTRATION: Progression of Early Subclinical Atherosclerosis (PESA) Study Identifier: NCT01410318.