Homocysteine and laminin are not prognostic markers in patients with septic inflammatory response syndrome

The association of plasma homocysteine levels with short-term mortality in sepsis patients: A meta-analysis

The association between plasma homocysteine (Hcy) levels and short-term mortality in sepsis patients remains unclear. This meta-analysis aimed to clarify this potential relationship. Following PRISMA 2020 and Cochrane Handbook guidelines, we conducted a comprehensive literature search in the PubMed, Embase, and Web of Science databases up to June 24, 2024. We included cohort studies that assessed the association between plasma Hcy levels and all-cause mortality in adult sepsis patients. Standardized mean differences (SMDs) and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using a random-effects model to account for potential heterogeneity. Nine cohort studies involving 771 sepsis patients were included. Overall, no significant difference in plasma Hcy levels was observed between survivors and non-survivors (SMD: -0.23, 95% CI: -0.84 to 0.37, P = 0.45), with substantial heterogeneity (I² = 86%). Subgroup analysis revealed lower plasma Hcy levels among survivors in Chinese patients (SMD: -1.56, 95% CI: -1.98 to -1.13, P < 0.001) but not in non-Asian patients. Plasma Hcy levels were not significantly associated with all-cause mortality (OR per 1-unit increment: 1.03, 95% CI: 0.95 to 1.11, P = 0.51), with notable heterogeneity (I² = 72%). However, a significant association was found in Chinese patients (OR: 1.09, 95% CI: 1.03 to 1.15, P = 0.003), but not in non-Asian patients. In conclusion, plasma Hcy levels were not generally associated with short-term mortality in sepsis patients. However, significant associations were observed in Chinese patients, suggesting potential ethnic differences that warrant further investigation.

Homocysteine and the Mortality of Critically Ill Patients: A Meta-Analysis

Prevalence of hyperhomocysteinemia (HHcy) is high in critically ill patients. However, the association between serum homocysteine level and outcomes of the critically ill patients remains unknown. We performed a meta-analysis of cohort studies to comprehensively evaluate the above association. Relevant cohort studies were identified by search of electronic databases including PubMed, Embase, Web of Science, Wanfang, and CNKI from the inception of the databases to February 5, 2022. A randomized-effect model incorporating the possible between-study heterogeneity was used to pool the results. Overall, 16 cohorts with 1663 critically ill patients who were admitted to the intensive care unit (ICU) were involved in the meta-analysis. Pooled results showed that compared to non-survivors of the critical illnesses, survivors had significantly lower serum level of Hcy at ICU admission [mean difference (MD): -3.42 μmol/l, 95% confidence interval (CI): -5.89 to 0.94, p=0.007; I2=86%]. Subgroup analysis showed that the difference of Hcy between survivors and non-survivors was significant in Asian patients (MD: -8.17 μmol/l, p<0.001), but not in non-Asians (MD: 0.30 μmol/l, p=0.62; p for subgroup difference<0.001). Moreover, meta-analysis with seven cohorts, all including Chinese patients, showed that HHcy at ICU admission was independently associated with a higher risk of all-cause mortality in critically ill patients (odds ratio: 2.99, 95% CI: 2.26 to 3.97, p<0.001; I2=69%). A higher serum level of Hcy at ICU admission may be associated with an increased risk of all-cause mortality in critically ill patients, particularly in the Chinese population.

The Effects of Homocysteine Level in the Critically Ill Patient. A Review

Increased levels of homocysteine (HCYS) represent a risk factor for a series of physiopathological conditions: mental retardation, cardiovascular and neurodegenerative diseases, Parkinson's and Alzheimer's disease, depression, osteoporosis, endothelial dysfunction and inhibition of cell proliferation. This paper aims to present the pathophysiological implications of HCYS and the correlation of hyperhomocysteinemia (H-HCYS) with critical condition in the intensive care unit (ICU). Hypovitaminosis B and folate deficiency is directly involved in the inhibition of HCYS metabolism and the accumulation of HCYS in the plasma and tissues. Critically ill patients are more prone to H-HCYS due to hypermetabolism and accelerated synthesis produced by reactive oxygen species (ROS). In conclusion it can be affirmed that the determination and monitoring of HCYS plasma levels may be of interest in optimizing the therapy for critically ill patients. Moreover, by controlling HCYS levels, and implicitly the essential cofactors that intervene in the specific biochemical pathways, such as vitamin B6, vitamin B12 and folic acid can provide a diversified and personalized treatment for each patient.

Plasma albumin cysteinylation is regulated by cystathionine beta-synthase

High homocysteine (Hcy) levels are a well-known independent risk factor for endothelial damage in atherosclerosis. We examined whether a rat intestinal model of ischemia-reperfusion was associated with high Hcy and with the modification of plasma albumin into cysteinylated species (CysAlb). The three treatment groups were as follows: midline abdominal incision (group A, n=10), followed by ligation of the superior mesenteric artery for a period of 2h (group B, n=3), and followed by reperfusion for 1h (group C, n=10). Hcy levels were 2.5-fold higher in group C than group A (p<0.05). 100% and 73.44+/-0.04% of Alb were modified into Cys species in groups C and B, respectively, compared to 51.2% in group A. A cystathionine beta-synthase (CBS) deficient mouse model, known to have high plasma Hcy levels, was also used to determine the extent of CysAlb. Hcy levels, %CysAlb, and %HcyAlb were 180.1+/-45.7 microM, 0%, and 23.4+/-4.4% in CBS deficient mice, while in control mice, those values were 5.7+/-1.8 microM, 24.2+/-4.1%, and 0%, respectively (p<0.05). High CysAlb and Hcy levels were observed in a rat model of bowel ischemia/reperfusion while high HcyAlb and Hcy levels with no CysAlb were observed in the CBS deficient mice. CysAlb may serve as a biomarker for the severity of gut ischemia, and high Hcy may explain endothelial damage associated with this model. Additionally, active CBS is essential for the formation of CysAlb.