Elevated Serum Complement C1q Levels After Traumatic Brain Injury and Its Association with Poor Prognosis

Abstract

Objective Complement C1q is implicated in neuroinflammation. We intended to discern the relationship between serum C1q levels and severity in addition to prognosis following traumatic brain injury (TBI). Methods In this prospective, observational study, serum C1q levels were quantified in 188 TBI patients and 188 healthy controls. Glasgow coma scale (GCS) and Rotterdam computed tomography (CT) classification were used as clinical and radiological indicators of severity. Patients with extended Glasgow outcome scale (GOSE) score of 1–4 at 6 months after trauma were considered to have a poor outcome. Multiple logistic regression model was built to ascertain the independent association of serum C1q levels with 6-month poor outcome. Receiver operating characteristic (ROC) curve was configured for analysis of prognostic capability with respect to serum C1q levels. Results TBI patients exhibited substantially higher serum C1q levels than controls (median, 223.9 mg/l versus 75.4 mg/l). Serum C1q levels of patients were tightly correlated with GCS score (r = −0.671), Rotterdam CT classification (r = 0.604) and GOSE score (r = −0.581). An area under the ROC curve was yielded of 0.793 (95% confidence interval = 0.728–0.849), and serum C1q levels above 345.5 mg/l discriminated the risk of 6-month poor outcome with 59.6% sensitivity and 92.6% specificity. Serum C1q levels above 345.5 mg/l retained as an independent predictor for 6-month poor outcome with odds ratio of 4.922 (95% confidence interval = 1.552–15.606; P = 0.017). Conclusion Elevated serum C1q levels are closely correlated with traumatic severity and independently predicted the risk of long-term poor prognosis after TBI.

Elevated Plasma Complement C1q Levels Contribute to a Poor Prognosis After Acute Primary Intracerebral Hemorrhage: A Prospective Cohort Study

“…Similarly, in patients with acute ischemic stroke, raised serum C1q levels were significantly and positively related to the National Institute of Health Stroke Scale and the diameter of maximum transverse section based on diffusion-weighted imaging of brain magnetic resonance imaging, indicating that serum C1q may be in close correlation with severity of neurological impairment and infarct volume ( 11 ). Nevertheless, in two previous clinical studies regarding human acute ischemic stroke, neurological function was not assessed and no multivariate analysis of note was performed ( 10 , 11 ) The valuable findings were that (1) a significant elevation of serum C1q levels existed in patients, as compared to healthy individuals; (2) serum C1q levels were independently correlated with clinical and radiological severity, which were reflected by GCS score and Rotterdam computed tomography classification; and (3) serum C1q appeared as an independent predictor for a poor 6 month post-injury outcome (extended GOS score of 1-4) ( 12 ). Such data indicate that circulating C1q may be a biomarker of acute brain injury.…”

“…Alternatively, increased serum C1q levels after acute ischemic stroke were positively correlated with neurological injury severity and infarct size of patients ( 10 , 11 ). Moreover, in a recent clinical study, elevated serum C1q levels were strongly correlated with traumatic severity and independently associated with a 6-month poor clinical outcome in patients with traumatic brain injury ( 12 ). Therefore, it is speculated that C1q might be a potential biochemical marker of acute brain injury.…”

Elevated Serum Complement C1q Levels After Traumatic Brain Injury [Letter]

“…We have read with great interest the recent paper by Yan et al, 1 published in Neuropsychiatric Disease and Treatment , discussing complement elements and prognosis in traumatic brain injury (TBI). Trauma is the leading cause of death in people aged 1–44 years.…”

“…In the article by Yan et al, 1 they describe the relationship between serum complement C1q levels and the severity of TBI and prognosis after TBI. This is a prospective study with a 6-month outcome analysis.…”

Serum NOX4 as a Promising Prognostic Biomarker in Association with 90-Day Outcome of Severe Traumatic Brain Injury

“… 5 , 6 Over the past several decades, biomarkers have drawn researchers’ interests with respect to severity assessment and prognosis prediction, in order to improve the prognostic predictive ability of GCS or Rotterdam CT classification. 7 , 8 Clearly, some biomarkers, such as S100B, glial fibrillary acidic protein, ubiquitin carboxyl-terminal hydrolase L1, myelin basic protein and neuron-specific enolase, have been confirmed to be highly related to trauma severity and clinical outcomes after TBI. 9–12 However, circulating levels of such biomarkers have not been routinely measured for clinical service.…”