Association Between Admission Ionized Calcium Level and Neurological Outcome of Patients with Isolated Severe Traumatic Brain Injury: A Retrospective Cohort Study

Low serum calcium is a novel predictor of unfavorable prognosis after traumatic brain injury

“…The interaction test indicated that lower serum calcium was more significantly associated with a 6-month unfavorable prognosis in mild patients than in moderate to severe patients. A recent study from Karawan et al also demonstrated the possible higher prognostic value of calcium in patients with a Glasgow Coma Scale >8 at admission, which partially coincides with our finding [ 27 ]. Therefore, at admission, attention and follow-up visits should be given to mild patients with lower serum calcium levels.…”

“…A lower serum calcium level can lead to bleeding, exacerbating secondary injury [ 7 ], and at admission is an independent risk factor for high hematoma volume and acute progression after spontaneous or traumatic ICH [ 12 , 26 ]. Karawan et al noted that mild admission hypocalcemia is associated with better neurological status at discharge in patients with isolated severe TBI [ 27 ]. Our study also reports on the prognostic predictive value of serum calcium in patients with TBI.…”

“…However, it is worth noting that Karawan et al also point out their own limitations (single-center retrospective study and relatively small sample size) and cannot exclude the effect of unmeasured or incompletely measured confounders. In addition, Karawan et al focused on neurological outcome at discharge (favorable neurological status defined by a modified Rankin Scale score of 0–2) [ 27 ], whereas we focused on prognosis at 6 months. Although our study differs from that of Karawan et al in many ways, such as design of the study, definition of outcomes, and time points for recording prognosis, our results both found a predictive value of calcium ions on the prognosis of patients with TBI.…”