Hemorrhagic transformation (HT) of cerebral infarction is considered as one of the most serious complications. Increasing evidence show that statin use might reduce the neuroinflammation and even improve clinical prognosis of stroke patients. However, there is not enough evidence that premorbid statin use may affect the risk of hemorrhagic transformation in stroke patients. The aim of our study was to investigate the role of premorbid long-term statin use in HT after acute ischemic stroke.

We retrospectively analyzed ischemic stroke patients in Huashan Hospital from 1 January 2012 to 31 December 2022 based on hospital electronic case records. Since thrombolysis or thrombectomy might interfere with the effect of statin use we excluded patients who received thrombolysis or thrombectomy treatment. A matched case-control study was conducted for reducing the impact of various confounding factors. The independent roles of statin use and serum lipids in HT was evaluated by binary logistic regression analysis.

A total of 254 ischemic stroke patients met the inclusion criteria and have been matched at 1:1 ratio, according age (± 5 years), admission NIHSS (± 3 scores), prior antiplatelets and anticoagulation therapy and previous stroke history. The patients without HT were regarded as control group. The percentage of HT was significantly lower in patients with premorbid long-term statin use (22.1 % vs. 41.7 %, p = 0.001). The incidence rate of diabetes mellitus and symptomatic deterioration (NIHSS increase ≥ 4) was higher in patients with HT. There were 18 patients having intracerebral hemorrhage before any reperfusion treatment. They had lower level of LDL-C (1.76 (1.73, 2.26) vs 2.72 (2.28, 3.09), p < 0.001) and were prone to previously take statins (55.6 % vs 16.5 %,p < 0.001). However, ECASS classification and all the outcome scores did not present any statistical difference in our study. In logistic regression analysis DM (OR = 2.001, 95 %CI 1.124–3.563, p = 0.018), increased levels of LDC-C (OR = 0.334, 95 %CI 0.172–0.649), p = 0.001) and HDL-C (OR = 13.303, 95 %CI 2.050–86.328, p = 0.001) were independent risk factors in occurrence of HT in patients with ischemic stroke, while premorbid statin use (OR = 0.269, 95 %CI 0.117–0.615, p = 0.002) could still be regarded as a protective factor in preventing intracranial hemorrhage after cerebral infarction. Additionally, lower level of LDL-C was also an independent risk factor in spontaneous HT after cerebral infarction (OR = 45.45, 95 %CI 5.62–333.33, p < 0.001), regardless of statin use.

Premorbid long-term statin use plays a protective role in the HT after cerebral infarction. However, low serum LDL-C and high HDL-C might be independent risk factors in the occurrence of HT irrespective of statin use. The previous statin uses and serum lipid levels have no impact on prognosis of HT.

Early hematoma expansion in intracerebral hemorrhage (ICH) patients is strongly associated with poor outcome and potentially preventable if high-risk patients are timely identified. We aimed to investigate whether a novel sign detected by noncontrast computed tomography (NCCT) named absolute hypodensity sign (AHS) was an appropriate candidate for hematoma expansion prediction.

Spontaneous ICH patients all underwent baseline NCCT scan within 6 h after ICH onset and the follow-up NCCT scan within 24 h after initial CT scan. AHS was defined as a hypoattenuating area with a distinct margin within the hematoma, the minimal density of which should be ≤30 Hounsfeld units. We used univariate and multivariate logistic regression analyses for determining the association between hematoma expansion and the presence of AHS. We also compared the diagnostic efficacy with blend sign and black hole sign.

A total of 348 ICH patients were included, 87 of which were found hematoma expansion. AHS was positive in 76 patients (21.8%) (κ = 0.88 for interrater reliability) and 63.2% of the patients with hematoma expansion were observed AHS. The multivariate logistic regression analysis demonstrated AHS was an independent predictor for hematoma expansion (odds ratio: 33.454, 95% confidence interval: 13.628–82.126, P < 0.001). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of AHS for hematoma expansion prediction were 63.2%, 92.0%, 72.4%, 88.2%, 84.8%, respectively, which were higher than blend sign and black hole sign except the specificity of black hole sign.

Our findings indicate AHS is a reliable predictor for early hematoma expansion due to its feasibility and convenience for clinical practice.