Serum Bilirubin Associated with Stroke Severity and Prognosis: Preliminary Findings on Liver Function after Acute Ischemic Stroke

ABSTRACT

Objective

This study investigates relationships between serum bilirubin, stroke severity, and prognosis of patients with acute ischemic stroke (AIS) to elucidate the roles of the liver in AIS.

Methods

This retrospective study collected data from 527 patients diagnosed with AIS within 24 hours after their symptom onset. Stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS). Mild stroke was defined as NIHSS≤5. Prognosis was assessed with modified Rankin Scale (mRS) on 90 days after AIS and good prognosis was defined as mRS≤2. The patients were divided based on their total bilirubin (Tbil) and direct bilirubin (Dbil) levels to study these serum markers’ association with the severity of stroke. Tbil levels were measured and compared with mRS on 90 days to analyze prognosis of mild stroke patients.

Results

Both Tbil abnormal (NIHSS = 6.8 ± 5.3) and Dbil abnormal groups (NIHSS = 7.3 ± 5.7) had higher NIHSS scores on admission than the normal groups (p< 0.05 or p< 0.01, respectively). Severity of stroke at discharge was similar between these groups (p = 0.025 and 0.019, respectively). Serum bilirubin levels were independently associated with stroke severity on admission and discharge after risk factors were adjusted (p< 0.001 and p< 0.05, respectively; β (95%CI) were 0.116 (0.064–0.167) and 0.058 (0.012–0.103), respectively). The average Tbil levels of mild stroke with good prognosis was 15.1 ± 6.4umol/l versus 11.8 ± 3.1umol/l with poor prognosis; this difference was statistically significant (p = 0.003). The same difference was observed with Dtil levels but it did not reach a significant level.

Conclusion

High Tbil and Dbil level within 48 hours of symptom onset could be an independent marker of severity of stroke on admission and discharge for all AIS patients. For patient with mild stroke, elevation of bilirubin after AIS suggests a good prognosis. These findings imply that the liver play the key roles in the mechanism of AIS.

KEYWORDS:

• Acute ischemic
• stroke
• liver
• total bilirubin
• direct bilirubin
• stroke severity
• prognosis

Acknowledgments

The authors gratefully acknowledge all individuals who participated in this study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was partially supported by the Beijing Tongzhou District Financial Fund(2022), the Laboratory Development Funds of Beijing Luhe Hospital and the Yunhe talent Program of Beijing Tongzhou District (2022).

Notes on contributors

Honglian Duan

Honglian Duan, an attending physician of department of Neurology, Beijing Luhe Hospital, Capital Medical University. She graduated from Capital Medical University. She mainly focus on the clinical and research work of the acute ischemic stroke and Neurological intensive.

Zhe Cheng

Zhe Cheng, an associate chief physician of department of Neurology, Beijing Luhe Hospital, Capital Medical University.He graduated from Capital Medical University. He mainly focus on the clinical and research work of the acute ischemic stroke and interventional treatment of cerebrovascular disease.

Ho Jun Yun

Ho Jun Yun, a researcher of Neurosurgery, Wayne State University School of Medicine (USA) .

Lipeng Cai

Lipeng Cai , an associate chief physician of department of Neurology, Beijing Luhe Hospital, Capital Medical University. She mainly focus on the clinical and research work of the acute ischemic stroke and neuroprotection.

Yanna Tong

Yanna Tong, an associate chief physician of department of Neurology, Beijing Luhe Hospital, Capital Medical University. She mainly focus on the clinical and research work of the acute ischemic stroke and neurological rehabilitation.

Zhenzhen Han

Zhenzhen Han, an attending physician of department of Neurology, Beijing Luhe Hospital, Capital Medical University.

Xiaokun Geng

Xiaokun Geng, a chief physician, and the department chairman of Neurology, Beijing Luhe Hospital, Capital Medical University. He has engaged in neurovascular intervention and the mechanism of cerebral and drug protection in stroke. In the past five years, he has published more than 80 SCI, which are all in mainstream academic journals exerting international influence in his professional field.

Yuchuan Ding

Yuchuan Ding is a professor of Neurosurgery, Wayne State University School of Medicine (USA) where he is a principal investigator of the Merit Review Award (I01RX-001964-01) from the US Department of Veterans Affairs Rehabilitation R&D Service. In the past five years, he has published more than 150 SCI, which are all in mainstream academic journals exerting international influence in his professional field.