The inverse association between the apolipoprotein E ε4 allele and C-reactive protein levels is stronger in persons with obesity and diabetes.

BACKGROUND: C-reactive protein (CRP) is lower in patients who carry the apolipoprotein E epsilon 4 allele variant (APOEε4) of the APOE gene. This could however be explained by other factors observed in APOEε4 carriers, such as lower body mass index (BMI), possibly less diabetes and more use of statins, all associated with CRP concentrations. OBJECTIVES: To assess the association between CRP and APOEε4 stratified by BMI, statin use and diabetes. METHODS: We included 2700 community-dwelling older adults from the Hordaland health study with genotyping of the APOE gene by a one-step polymerase chain reaction and CRP measured using immuno-MALDI-TOF MS. Differences in CRP concentrations by APOE (ε4 vs no ε4) were assessed using the Mann-Whitney U tests, also stratified by statin use, diabetes and BMI categories. Finally, we performed linear regression with log (CRP) as the outcome and APOEε4 together with statin use, diabetes, BMI and their respective interactions. RESULTS: CRP was higher in APOEε4 carriers irrespective of BMI, diabetes and statin use. In APOEε4 non-carriers, CRP was elevated with diabetes and obesity as expected. However, this was attenuated or even reversed in APOEε4 carriers. Such differences were not observed for statin use. CONCLUSIONS: Statin use, obesity or diabetes did not confound the known association between the APOEε4 allele and lower CRP. Our data suggest that CRP is less responsive to inflammatory cues involved in diabetes and obesity in APOEε4 carriers. Epidemiological studies should take note of these relationships, as CRP, APOEε4, diabetes and obesity are both linked to neurodegenerative and cardiovascular disease.

Compositional plaque progression in women and men with non-obstructive coronary artery disease.

Background: In coronary artery disease (CAD), plaque progression and plaque composition are associated with cardiovascular risk. Whether compositional plaque progression in non-obstructive CAD differs between women and men is less studied. Methods: We included 31 patients (42% women) with chronic non-obstructive CAD from the Norwegian Registry of Invasive Cardiology, undergoing serial coronary computed tomography angiography (CCTA) on clinical indication (median inter-scan interval 1.8 [1.5-2.2] years). We performed quantitative and qualitative plaque analysis of all coronary artery segments. Results: Women were older compared to men (65 ± 8 years vs. 55 ± 12 years, p = 0.019), while there was no difference in the prevalence of hypertension, diabetes, smoking or statin treatment between groups. At baseline, women had a higher total plaque burden, more calcified plaques, and less fibro-fatty and necrotic core plaques compared to men (all p < 0.05). During follow-up, men showed faster progression of fibro-fatty plaques (4.0 ± 5.4 % per year vs. -0.6 ± 3.1 % per year, p = 0.019) and a greater reduction of fibrous plaques (-7.3 ± 6.1 % per year vs. 2.1 ± 7.2 % per year, p = 0.003) compared to women even after age adjustment. At follow-up, total plaque burden remained higher in women compared to men (24.9 ± 3.3 % vs. 21.1 ± 2.6 %, p = 0.001), while men had an increase in fibro-fatty (21.2 ± 9.3 % vs. 28.6 ± 9.8 %, p = 0.004) and necrotic core plaques (5.6 ± 3.6 % vs. 10.8 ± 7.2 %, p = 0.006), and a decrease in fibrous plaques (69.0 ± 11.9 % vs. 54.7 ± 13.7 %, p < 0.001). Women's plaque composition remained unaltered. Conclusion: In non-obstructive CAD, serial CCTA demonstrated a higher total plaque burden and a stable plaque composition in women, while men had a faster progression of unstable low-attenuating fibro-fatty plaques.Clinical trial registration: ClinicalTrials.gov: Identifier NCT04009421.