Introduction: Recent publications have taken the idea about D-dimer as a potential
marker for deadly progression of COVID-19 disease. Objective: Evaluation of international
observations involving Hungarian patients, and establishing the D-dimer level elevation
as a positive predictive marker for case fatality. Methods: Therefore these authors
have elaborated the data of 51 patients positive for SARS-CoV-2 confirmed by RT-PCR
in a retrospective study. Biostatistical methods used: binary logistic regression.
Evaluated parameters: medians between deaths and survivors, odds ratio calculation
between deaths and survivors. Results: Of the 51 patients 13 died within 2 weeks of
hospitalization. We found that the traditional D-dimer positivity determined at a
cut-off value of 0.5 mu g/ml FEU had low predictive value for lethality (0.36). Using
the predictive value, the age-standardized D-dimer cut-off value, the odds ratio increased.
When the raw concentration values were compared between the survival and non-survival
group, there were sharp differences. The median value at survival was 0.65 mu g/ml
FEU, otherwise the concerned median at lethality was 2.21 (p = 0.001). We also examined
if the D-dimer reached or exceeded 4 times the cut-off, furthermore, what the risk
was for case fatality. Logistic regression coefficient was 1.64 (p = 0,00183); odds
ratio = 5.17 (CI 95% = 1.32-20.22). Another option was to compare the age of survived
and dead patients for odds of lethality. As only 1 patient died below 80 years, the
authors calculated the odds of age beyond 80 for lethality. The concerned odds ratio
was 20.7 (CI 95% = 2.41-175.5). Conclusion: D-dimer marked elevation and risk for
lethality seemed to be relevant. On the other hand, the collinearity between aging
and D-dimer elevation is a confounding bias. It is important to consider the size
of elevation of D-dimer, when the concentration is equal or greater than four times
of cut-off the case lethality.
