Association of prehypertension and hyperhomocysteinemia with subclinical atherosclerosis in asymptomatic Chinese: a cross-sectional study

The association between hyperhomocysteinemia and the prevalence of bilateral carotid atherosclerotic plaques in a middle-aged population

OBJECTIVE

We conducted a cross-sectional study to investigate the impact of hyperhomocysteinemia (HHcy) on the prevalence of CASP among middle-aged individuals, aiming to provide insights for CASP prevention.

METHODS

1105 subjects were categorized into HHcy group or normal tHcy group based on their plasma total homocysteine (tHcy). All participants underwent carotid artery ultrasonography to assess the presence of unilateral and bilateral CASP. Comparative analyses of demographic and clinical data were conducted between the two groups. Logistic regression and prespecified subgroup analyses were performed to determine whether HHcy independently contributed to bilateral CASP.

RESULTS

132 individuals exhibited bilateral CASP. The prevalence of bilateral CASP was significantly higher in the HHcy group compared to the normal tHcy group (21.55 % vs. 10.82 %, p = 0.003). Univariate logistic analysis showed a significant association between HHcy and the prevalence of bilateral CASP (OR = 2.056, 95 %CI 1.089-3.881, p = 0.026). In all four models of multivariate logistic analysis, HHcy consistently emerged as an independent risk factor for bilateral CASP, with odd ratios of 1.958, 2.047, 2.023, and 2.186. This association remained significant across all five subgroups stratified by age, sex, hypertension, diabetes, and BMI.

CONCLUSION

Our studies demonstrated HHcy was an independent risk factor for the prevalence of bilateral CASP in the middle-aged population. Theses results emphasized the importance of addressing HHcy in preventive strategies aimed at mitigating the burden of CASP among middle-aged individuals.

Hyperhomocysteinemia Promotes Carotid Artery Damage in Newly Diagnosed Type 2 Diabetic Patients Without Hypercholesterolemia

Background: The relationship between serum homocysteine levels and carotid artery damage in subjects with newly diagnosed type 2 diabetes mellitus remains unclear. The effect of hyperhomocysteinemia (HHCY) on carotid artery damage in patients with different cholesterol levels needs to be further investigated. Methods: In total 456 newly diagnosed type 2 diabetes from Beijing Chaoyang Hospital were recruited into the study. Patients were divided into four groups according to the levels of serum homocysteine and cholesterol. Carotid artery damage was defined as thickened intima-media and/or plaque formation. Results: In all the subjects, 80.2% patients had HHCY. The incidence of carotid artery injury was significantly lower in diabetic patients with normal homocysteine levels and nonhypercholesterolemia. Spearman correlation analysis showed homocysteine was positively correlated with free fatty acid and negatively correlated with glucose metabolism parameters. Logistic regression showed HHCY was correlated with carotid artery injury after adjusting for traditional cerebrovascular risk factors in type 2 diabetes without hypercholesterolemia (odds risk = 3.197, P = 0.022). Whereas HHCY was not associated with carotid artery injury in either total study population or hypercholesterolemia subgroup. Conclusions: HHCY was correlated with carotid artery damage in newly diagnosed type 2 diabetic subjects without hypercholesterolemia. How to improve the adverse vascular outcomes mediated by HHCY for diabetic patients needed further investigation.

The impact of homocysteine on the risk of coronary artery diseases in individuals with diabetes: a Mendelian randomization study

AIMS

Observational studies have reported that homocysteine (Hcy) is associated with an increased risk of coronary artery disease (CAD) in individuals with diabetes, though controversy remains. The present study aimed to investigate the causal association between Hcy and CAD in individuals with diabetes.

METHODS

A 2-sample Mendelian randomization (MR) study was designed to infer causality. Genetic summary data on the association of single nucleotide polymorphisms (SNPs) with Hcy were extracted from the hitherto largest genome-wide association study (GWAS) of up to 44,147 individuals of European ancestry. SNP-CAD data were obtained from another recently published GWAS which included 15,666 individuals with diabetes (3,968 CAD cases, 11,696 controls). The fixed-effects inverse variance-weighted method was employed to calculate the effect estimates. Other robust methods and leave-one-out analyses were used in the follow-up sensitivity analyses. Potential pleiotropy was assessed with the MR-Egger intercept test.

RESULTS

The 2-sample MR analysis suggested no evidence of an association between genetically predicted plasma Hcy levels and CAD risk in individuals with diabetes (odds ratio = 1.14, 95% confidence interval: 0.82-1.58, p = 0.43) using 9 SNPs as instrumental variables. Similar results were observed in the follow-up sensitivity analyses. The MR-Egger intercept test indicated no evidence of directional pleiotropy (intercept = 0.03, 95% confidence interval: - 0.08-0.03, p = 0.35).

CONCLUSION

This 2-sample MR analysis found no evidence of a causal association between plasma Hcy levels and CAD risk in individuals with diabetes.

Associations between hyperhomocysteinemia and the presence and severity of acute coronary syndrome in young adults ≤ 35 years of age

Background

The prevalence of acute coronary syndrome (ACS) continues to increase among young Chinese adults. Homocysteine (HCY) has been suggested as a promoter of atherosclerosis leading to coronary artery disease (CAD). Yet, it remains uncertain whether HCY is associated with the ACS and the severity of coronary artery stenosis in young adults.

Methods

Young patients (18–35 years of age) diagnosed with ACS who underwent coronary angiography (CAG) at Anzhen Hospital between January 2013 and June 2019 were assigned to the ACS group. As confirmed by CAG during the same period, an equivalent age-matched population without CAD was assigned to the non-CAD group. A serum HCY level > 15 µmol/L was defined as hyperhomocysteinemia (HHCY). The Gensini score assessed the severity of coronary artery stenosis.

Results

A total of 1103 participants, including 828 ACS patients and 275 non-CAD subjects, were enrolled in this study. Young ACS patients had higher level of serum HCY and greater prevalence of HHCY compared with non-CAD subjects [for HCY, 16.55 (11.93–29.68) vs 12.50 (9.71–17.42), P < 0.001; for HHCY prevalence, 62.08% vs 26.18%, P < 0.001]. Multivariate logistic regression analysis with the stepwise method indicated that HHCY was an independent predictor associated with the presence of ACS, after adjusting for traditional confounders (OR, 4.561; 95% CI, 3.288–6.327; P < 0.001). Moreover, young ACS patients with HHCY had increased prevalence of ST-segment elevation myocardial infarction (STEMI) (P = 0.041), multi-vessel disease (P = 0.036), and decreased value of left ventricular ejection fraction (LVEF) (P = 0.01). Also, the HCY level was significantly correlated with Gensini Score in ACS patients (r = 0.142, P < 0.001).

Conclusion

HHCY is significantly associated with the presence of ACS and the severity of coronary artery stenosis in young adults ≤ 35 years of age.

No causal effects of plasma homocysteine levels on the risk of coronary heart disease or acute myocardial infarction: A Mendelian randomization study

BACKGROUND

Although many observational studies have shown an association between plasma homocysteine levels and cardiovascular diseases, controversy remains. In this study, we estimated the role of increased plasma homocysteine levels on the etiology of coronary heart disease and acute myocardial infarction.

METHODS

A two-sample Mendelian randomization study on disease was conducted, i.e. "coronary heart disease" (n = 184,305) and "acute myocardial infarction" (n = 181,875). Nine single nucleotide polymorphisms, which were genome-wide significantly associated with plasma homocysteine levels in 57,644 subjects from the Coronary ARtery DIsease Genome wide Replication and Meta-analysis (CARDIoGRAM) plus The Coronary Artery Disease (C4D) Genetics (CARDIoGRAMplusC4D) consortium genome-wide association study and were known to be associated at p < 5×10-8, were used as an instrumental variable.

RESULTS

None of the nine single nucleotide polymorphisms were associated with coronary heart disease or acute myocardial infarction (p > 0.05 for all). Mendelian randomization analysis revealed no causal effects of plasma homocysteine levels, either on coronary heart disease (inverse variance weighted; odds ratio = 1.015, 95% confidence interval = 0.923-1.106, p = 0.752) or on acute myocardial infarction (inverse variance weighted; odds ratio = 1.037, 95% confidence interval = 0.932-1.142, p = 0.499). The results were consistent in sensitivity analyses using the weighted median and Mendelian randomization-Egger methods, and no directional pleiotropy (p = 0.213 for coronary heart disease and p = 0.343 for acute myocardial infarction) was observed. Sensitivity analyses confirmed that plasma homocysteine levels were not significantly associated with coronary heart disease or acute myocardial infarction.

CONCLUSIONS

The findings from this Mendelian randomization study indicate no causal relationship between plasma homocysteine levels and coronary heart disease or acute myocardial infarction. Conflicting findings from observational studies might have resulted from residual confounding or reverse causation.

Association Between Folic Acid Supplementation and Retinal Atherosclerosis in Chinese Adults With Hypertension Complicated by Diabetes Mellitus

Background: This cross-section investigation included 2,199 participants with hypertension complicated by diabetes mellitus, a cohort of the China Stroke Primary Prevention Trial in which 20,702 patients with essential hypertension were given enalapril with folic acid or enalapril-only double-blind treatment for 5 years. This study aimed to explore the correlation between folic acid supplementation and retinal atherosclerosis (RA) in adults with hypertension complicated by diabetes mellitus.

Methods: The diagnosis of RA was determined by non-mydriatic fundus photography and classified by the Keith-Wagener-Barker system. The statistical correlation of folic acid supplementation with RA prevalence and severity was assessed.

Results: Of our cohort, 1,698 (77.6%) participants were diagnosed with RA, and the prevalence in males and females was 78.0 and 75.6%, respectively. Participants in the enalapril group had higher total homocysteine (tHcy) levels than those in enalapril–folic acid group. Compared with the enalapril group in the tHcy > 15 μmol/L group of females, the odds ratio for the enalapril–folic acid group was 0.28 (95% confidence interval, 0.11–0.67, P = 0.0061).

Conclusions: The prevalence of RA was high (77.6%) in our cohort of adults with hypertension complicated by diabetes mellitus. Folic acid supplementation was significantly associated with reduced risk of RA in females with hyperhomocysteinemia. No significant association were seen in males.

Association of blood pressure components with mortality and cardiovascular events in prehypertensive individuals: a nationwide population-based cohort study

BACKGROUND

The effects of each blood pressure index [systolic and diastolic blood pressure (SBP, DBP), pulse pressure (PP), mean arterial pressure (MAP)] on the occurrence of mortality and cardiovascular (CV) events have not yet been investigated in prehypertensive populations.

METHODS

A total of 30,258 prehypertensive Korean participants underwent periodic health examination between 2003 and 2004 were enrolled, and the associations of BP components with mortality and CV events were investigated. Moreover, based on the DBP [80 ≤ DBP <90 mmHg (N = 21,323) and DBP <80 mmHg (N = 8,935)], the effects of BP components were also evaluated.

RESULTS

Multivariate Cox analyses in prehypertensive group revealed that the hazard ratios (HRs) were 1.121 and 1.130 per 10 mmHg increase in SBP and PP for mortality, respectively. Additionally, 10 mmHg increase of SBP (HR:1.090) was still significantly, but increase of PP (HR:1.060) was marginally associated with higher incidence of CV events. However, there were no significant associations with increase in DBP or MAP on adverse clinical outcomes in prehypertensive group. In the prehypertensive subjects with DBP <80 mmHg, CV events more frequently occurred by 38.8% and 28.5% per 10 mmHg increase in SBP and PP, respectively.

CONCLUSIONS

Prehypertensive subjects might need to be cautioned when they have high SBP or PP with low DBP even in healthy populations. Key message Prehypertensive subjects should be cautioned when they have high-systolic blood pressure or pulse pressure with low-diastolic blood pressure, even without previous hypertension, diabetes mellitus or chronic kidney disease.