#Sepsis #Homocysteine #Biomarker #Mortality
#PersonalizedMedicine #IntensiveCare
Sepsis is an exacerbated systemic inflammatory
response triggered by infection, leading to acute organ dysfunction. It remains
one of the leading causes of death in hospital settings. Despite advancements
in early diagnosis, resuscitation protocols, and antimicrobial treatments,
short-term mortality remains high, reaching up to 30% in severe cases. Current
treatments are primarily symptomatic and standardized, with limited ability to
identify high-risk patients or tailor the immune response on an individual
basis.
In light of this therapeutic deadlock,
identifying reliable prognostic biomarkers is a major lever for refining risk
stratification, guiding early interventions, and potentially steering medicine
towards a more personalized approach. Homocysteine (Hcy), a sulfur-containing
amino acid derived from methionine metabolism, has emerged as a biomarker of
interest. Known for its harmful effects on vascular endothelium, its role in
oxidative stress, its promotion of a pro-thrombotic state, and its activation
of systemic inflammation, Hcy exhibits a biological profile directly linked to
the pathophysiological mechanisms of sepsis.
However, available clinical data remain
heterogeneous and sometimes contradictory, particularly due to methodological
differences and potential ethnic variations in homocysteine metabolism. This
study was initiated within that context. Its dual objective was to clarify the
association between plasma Hcy levels at admission and short-term mortality in
sepsis patients, and to assess whether this relationship varies based on
patients' geographic or ethnic origin.
Read next: Sepsis: A Critical Challenge for Global Health
Homocysteine: a real alarm signal?
Nine cohort studies, both prospective and
retrospective, including
771 adult patients with sepsis, were selected and
analyzed. In each study, plasma Hcy concentrations were measured
within 48
hours of diagnosis — a critical window for prognostic evaluation. The analysis
followed two main axes:
- Comparison of
mean Hcy levels between survivors and non-survivors;
- Calculation
of mortality risk associated with a unit increase in Hcy (adjusted odds
ratio).
On a global scale, no statistically significant
association was found between Hcy levels and short-term mortality. However, a
strong and significant association was observed specifically in
Chinese-origin
patients, in whom higher Hcy levels correlated with an increased risk of death.
No such link was found in non-Asian patients. This disparity suggests a
probable ethnic influence, possibly related to genetic polymorphisms and
specific dietary factors. Sensitivity analyses confirmed the
robustness of these
results, but
methodological heterogeneity between studies remained high (I²
> 70%), underscoring the need for more harmonized future research.
Read next: Sepsis and memory: a link not to be forgotten!
Towards more targeted medicine
Sepsis continues to be one of the greatest
challenges in modern intensive care medicine, with a daunting prognosis and
high mortality. The absence of reliable prognostic biomarkers still hampers the
possibility of personalized care, making risk stratification often imprecise.
In this context, homocysteine is garnering increasing interest due to its
well-established role in oxidative stress, systemic inflammation, and
endothelial dysfunction — all key mechanisms in sepsis pathophysiology.
The results of this study suggest that
homocysteine could play a discriminating role in certain subgroups, especially
in patients of Asian origin. This disparity might be explained by genetic
determinants (such as the MTHFR C677T polymorphism) and nutritional
deficiencies (folate, vitamin B6 and B12) that affect its metabolism and
clinical impact. These observations call for a reassessment of biomarker use in
sepsis. Rather than aiming for a universal indicator, a more personalized
approach is needed, taking into account the genetic, ethnic, and nutritional
specificities of patients.
Additional studies are necessary to confirm
these results, relying on more homogeneous methods and larger populations.
Future research should be multicenter, prospective, and integrate genetic,
nutritional, and clinical data collected from the earliest hours of sepsis. The
goal will be to better understand whether homocysteine can truly serve as a
risk biomarker in certain patients. In parallel, it would be worthwhile to
assess, through well-designed trials, whether supplementation with folates and
B vitamins could improve survival. These directions pave the way toward a more
personalized approach in intensive care, better adapted to the biological
characteristics of each patient.
Read next: Sepsis and Interleukin: A Connection?
